Modified DSLR VS Cooled OSC - Part 1: NOT What I Expected!
ฝัง
- เผยแพร่เมื่อ 2 ส.ค. 2024
- In this video we set out to test an astro modified DSLR vs a dedicated cooled astronomy camera.
The results are not at all what I expected.
TEST DATA is here - drive.google.com/drive/folder...
file names - DSLR ROSETTE TEST 19x5m & OSC ROSETTE TEST 19x5m
AFFILIATE LINKS!!
Amazon Affiliate Links! - Anything you buy through one of these links will give me a small commission at no extra cost to yourself!
Amazon UK - amzn.to/3EOCgpV
Amazon US - amzn.to/3quGPlD
Topaz Denoise, Gigapixel & Sharpen AI are some of my favorite software to aid in astro processing! If you buy the software through this link I would receive a commission at zero extra cost to yourself!
Topaz Labs Affiliate Link! - topazlabs.com/ref/1133/
Topaz Labs Discount Code for my viewers! - FRIEND15
High Point Scientific Affiliate Links!
High Point Scientific Affiliate Link - www.highpointscientific.com/?...
Orion Telescopes & Binoculars Affiliate links!
www.pjatr.com/t/R0FHSUdKTEFGS...
www.pntrs.com/t/S0BMQ0pFQEVHR...
www.pntrs.com/t/R0JJSEVIS0ZCR... - วิทยาศาสตร์และเทคโนโลยี
Hey man! I'm afraid you didn't compare cameras but sky conditions at different times :)
I immediately thought the cooled OSC camera imaged during a time of bad transparency (and potentially seeing). To check that (as well as I can with just the stacked image - ideally I'd need the sub-frames directly without calibration), I star aligned one image to the other so we got the same scale, cropped to remove any stacking artifacts (applying same crop to each image so we have same FOV at same scale) applied a first order ABE on each, then used the SFS to check statistics. As I expected, the OSC image gets far fewer stars detected (1350 vs 1800) and a worse FWHM than the DSLR image. This is a strong indicator of atmospheric/lighting/guiding conditions influencing the end result, rather than the camera itself.
This is why I do such tests strictly right before and right after Meridian (so same object altitude), on the same night, across a total timespan of at most 1 hour (usually closer to 30 minutes), while closely monitoring conditions. You mentioned that clouds cut the OSC session short, and then part of it was taken the night after the moon was closer to the Rosette - it's likely that subs prior to the clouds appearing started suffering from poor transparency, and the subs with the moon closer would also have suffered.
That being said you proved something that bears repeating: great images can be taken with a humble DSLR!
Luke, it seems like you just need to get another EQ8 and a 250pds and run both AT THE SAME TIME 😀 also make sure they sit on the exact same latitude so position them west/easy with respect to one another 😄 that being said, Cuiv has a point. The moon and object altitude might’ve had an impact.
Hey Cuiv! - very interesting points mate :-)
Thank you so much for watching and sharing your thoughts, always a true pleasure!
My feeling is that there's something else at play rather than the seeing here, it seemed to me that the conditions were quite stable all night! - I could easily be wrong though, but another pair of eyes checking things would be good :-D
To that end, I've just uploaded the last stacked sub from the DSLR, and the first stacked sub from the OSC - if there's a big difference in FWHM then I suspect it wasn't down to seeing as the time between those two subs is minimal, and both were cloudless :-)
My thinking is that there's potentially some in-camera sharpening that's just native and cannot be turned off?
All the best!
Luke
Hey Kamil! :-) Cuiv definitely raises some interesting points! I know you're only kidding but man, can you imagine having the resources to do a comparison like that haha!! :-D
I hope that you enjoyed the video mate, and still found it somewhat valid!
If sky conditions or moon brightness or light pollution didn't change, the camera with the bigger pixel will win the contrast battle, it's why Trevor is now using an ASI2400 OSC on a redcat, completely undersampling. I believe Dylan did a video on this as "Astro cheating" by undersampling, then drizzle after. More contrast, lesser star form issues, etc. If you use a ASI 294mc your results would be near the same I assume, very close pixel sizes, as long at the exposures are matched based on the histogram. Bigger pixel camera will yeild a higher median histogram value if at the same exposure time as another camera. The 2600mc should have a higher sensitivity that the Canon but a picture speaks a thousand words. You can try and bin the 2600mc but I found on binning osc's don't always make for better detail. I would have to investagate the noise curves online to see if I can find more for ya Great gob on this Luke and look forward to more investigative videos like this.
P.s. if you did a star alignment in PI on the 2600 re the canon , you need to be careful with this as it will perform indirect noise reduction if you are using the spline method because the software will use an algorithm to compute the date to match position of the reference. therefore your STF stretch will have a different "visual" affect when stretched. If you use spline method (mainly for chromatic distortion),, down at the bottom on the alignment process under interpolation, turn off auto and try bicubic spine as a start. Something i get weird artifacts when it is set to auto.
@@billblanshan3021 Thank you for the insights Bill!! Great points :-)
I'm super glad to hear you liked the investigative style mate, it was interesting to make as it's a question I've often wondered myself!
I do make a short mention of the difference in sampling ratio quite late in the video, when looking at the top right pillar section, but certainly I should have emphasized this point more in the video! again, super suggestion - thank you!
RE: alignment, I did it visually & by hand with no transformation to the image scale, just cropped the 2600 to match the canon field of view basically :-D
Thank you so much for watching, and for your continued support my friend!
Have a wonderful weekend :-)
Well done! I've long held that camera choice is the least important factor in deep sky imaging, esp. if night-time temps are reasonable (e.g.
Hey Nico! - Awesome to see you here, I'm a long time fan - thank you very much for giving this a watch and sharing your thoughts! :-)
I totally agree man, I've seen some incredible results from Japanese astrophotographers using DSLR's - one chap in particular always springs to my mind, Toshiya Arai - he owns & uses a multitude of cameras, yet you still see him busting out the D810a to great effect.
I hope part 2 goes as well as this video has!
Thanks again for watching, and clear skies!
Luke
I think it’s the prestige of the local Japanese market the drives Canon and Nikon to come out with “a” model cameras. I hadn’t followed it lately but if modified DSLR/M cameras from Japanese companies are still big there vs cooled CMOS cameras made in China, then perhaps we will see another R series “a” model from Canon, likely a variant of whatever replaces the original R. The R6 has terrible amp glow so unless Canon fixes that (today’s v1.5 firmware update didn’t do it!) it’s not a good candidate for modifying.
Interesting points Alan! - thank you for sharing 👍👍
I'd love to see Canon/Nikon further flesh out their product ranges with more astro offerings, my fingers will be crossed for it anyway 🤞
Clear skies!
You guys should do a target face off!
Thanks for this. I’m a visual observer who is now taking my first tentative steps into AP. This has shown me that I won’t be wasting my time starting out with a DSLR
No problem my friend! - Thanks so much for watching and taking the time to comment! :-) Clear skies and good luck on the path into AP!
This is excellent, I think its very helpful for people to se the difference between a modded DSLR an a OSC as that is the usual upgrade path and one I am about to embark on! Mind you I plan to use both at the same time to maximise my imaging productivity due to limited opportunities so I am not relying solely on an improvement in imaging quality. Another reason for getting a OSC rather than another DSLR is the cooling potential, where I am the summer night time air temperatures don't drop much below 30 which isn't great for noise on a DSLR.
Anyway these comparisons are massively helpful, keep up the good work!
Hey there Mart!
Thank you for the lovely and well thought out comment my friend, I certainly agree with the points made! As you say, Osc really does have a huge advantage in that no matter the time of year, the sensor is freezing cold and making very little thermal signal! I'm sure this test redone in summer would have been interesting too :-)
Thank you very much for watching mate, it's appreciated 👍👍
Excellent comparison done as well as could be expected. Doing A-B comparisons of astro gear is always tough as sky conditions can change quickly. I look forward to seeing more of your testing. Clear skies!
Hey Alan! - That's very kind of you to say, thank you! :-)
Part 2 has been recorded and I think it went better overall, certainly nailed down more variables! it should be out at the weekend so I hope you will enjoy it when you get the chance :-D
Thanks for watching!!
Wow, this was beyond excellent! Look forward to seeing more insights. This is good news for those who cant afford dedicated, cooled, OSC's!
I'm glad you liked it Robert! - Hopefully part 2 doesn't disappoint either mate! :-D
Clear skies!
I just thought that maybe it’s a Canon sensor vs. a Sony sensor and Canon “color science” wins lol. (I happen to be a huge Canon fan with the EOS R/RP for regular photography). Which Sony dslr uses the same sensor as the ZWO2600 OSC? It might be interesting to compare that Sony DSLR too.
@@bobbeanbags Hey Robert! - re: the sensor, it's used by Fuji XT3 cameras! :-)
I like this sort of comparison. Yesterday I ordered an ASI533 MC PRO to finally venture into the world of dedicated astro cameras. I was out on November 23 shooting with my unmodded D7500. No filters and a bright moon chasing my targets of the Horse Head Nebula and Witch Head nebula. Reached minus 7c for ambient that night. Full set of all calibration frames taken, including dark flats. I was not expecting good results, as the camera really frosted up and seemed to produce some weird looking dark frames. Processed rather simply in SIRIL and GIMP and I am amazed at the great results. Lots of great images on Astrobin taken with DSLR cameras.
Hey there mate!! - firstly, huge congratulations on your new camera, the 533 is a lovely bit of kit! :-)
So glad to hear you like the test, I should have to revisit it I think though, too many questions raised!
I'm happy to hear your shot with the unmodded d7500 went well, I did all my AP for a long time with an unmodded DSLR and the results were always better than expected I feel! :-) That said, modding does make a world of difference!!
Thank you so much for watching mate,
Clear skies!
Hey Luke, another really good video! love these types of comparison vids. I think this proves perfectly just how sensitive the conditions are to overall image quality. The humble eyeball can never see the tiny variations in seeing conditions and this shows that even the king of OSC cameras will struggle to match a DSLR with better seeing. I would argue what you've proven here is that you can capture awesome images with pretty much anything if you get the right conditions... Nice one!
Hey Steve! - thanks so much mate, I am glad that you've enjoyed the video! :-D
On the note of seeing - I did take a look at the last sub from the dslr, and first from the OSC - about 30 mins between them for a fairer comparison, and the result was the same really! I think there's something more at play than the seeing here which is going to need more testing :-D hopefully I'll have a chance sooner rather than later, it's interesting to try and figure out!
I deffo agree with what you are saying though, a dslr can still produce a good image for sure when compared to OSC!! 👍👍
Thanks for watching!
@@lukomatico it's certainly unexpected in that case. I'm intrigued to see where this goes with dedicated osc cameras costing so much... Perhaps we're doing it all wrong! 🤣
Great video luke and I’m amazed by how well the DSLR did. I’m just reading through the comments the video has raised some really interesting questions, looking forward to part 2 👍 keep up the great work
Thanks for checking it out mate!! - glad you liked it :-D
Very interesting test, thanks for taking the time to do it. Since clouds affected the 2600 test, it could be that the sky quality was deteriating before that (as has been mentioned in other posts). It would be interesting to compare the first and last light frame from each test to assess any image degradation. Your are always going to be paying a huge price premium for astro cameras which are made in far fewer numbers but we’ed all like to think we are getting some performance benefits as well. Worth repeating on a cloudless night.
Hey Cliff! I was happy to do it, thank you for watching! :-) literally just while I type this I have uploaded the last stacked image from the dslr, and the first one of the OSC so they can be compared! :-D great idea mate, if there's a big difference in FWHM then it can't be down to seeing really you'd think at that point?
Cheers!!
I see you’ve channeled your inner scientist Luke. Love how you’ve made every attempt to control the extraneous variables. As I learned in my education, it’s the unexpected or conflicting results that offer the most insights. I appreciate your curiosity as you attempt to shed light on an issue that at least for me, remained unclear-cooled camera vs. DSLR. I agree that more experimenting needs to be done, nevertheless, at least you’re intent on providing-as much as possible-your objective impressions on this issue. Now, if you wanted to go out and buy the exact same duplicate scope, mount, etc. and set up both scopes to image simultaneously on the the same night…LOL Aside from breaking the bank, at the very least, you get us to see that when it comes to astrophotography, there’s always one more question that needs to be asked. And kudos to you Luke for asking it.
Hey there Joe! - As always mate, I look forwards to hearing your insightful and thoughtful comments, thank you for taking the time to share!
It's an interesting message indeed that you mention, about the unexpected results being the most insightful, definitely they pique curiosity in a way that having an expected result does not!
I'd love to test this further, and I think I shall - it seems to have struck a nerve of intrigue in a lot of people so far! :-)
Thank you for watching Joe, I do appreciate it mate!
All the best,
Luke
Another great video mate well done. I miss my old modded T5i, I reluctantly sold mine to put towards an OSC. Such a great camera how versatile it was, I might have to get another. CS.
Hey mate! :-D I certainly hear what you are saying, a modded dslr is a versatile beast!
Thanks for watching!
Wow mate, when we spoke about this in the week, I wasn’t expecting to see such results. It’s certainly puzzling me. I think a broadband target next is a great idea. Looking forward to it already
Hey matey! - It's certainly left me scratching my head a bit, glad I'm not the only one actually haha!
I'll have to look into further tests!!
Thank you so much for watching and supporting my friend, I appreciate it :-)
Clear skies!
Im surprised that the dslr can actually compare relatively well to the dedicated one. Not what i expected neither lol. Keep up the great work and clear skies!
Hey Savjol!! You and me too my friend, what a surprise it was haha!! :-)
Thank you so much for watching, I hope you may enjoy a part 2! :-D
Clear skies!
Possible variations in sky conditions aside I'm still shocked by how well the DSLR held up here! There's always something to scupper the perfect test (trust it to be the clouds hey!) Other than imaging on different nights which was the clouds fault, I think you did a cracking job covering as many variables as possible right through to the processing side of things. DSLR verses OSC is such a big question for folks, so it's cool that you recognise this and made a video which will interest so many of us. Totally agree this needs further investigation as I too expected the OSC to wipe the floor with the 700D, wtf? Even if the seeing was in the 700D's favour I wouldn't have expected this result quite frankly. Really fab video Luke, thanks for making it : )
Hey Chris! - I'm stoked up to hear that you liked the concept mate, it really is a shame that clouds ruined the validity somewhat, but as you say, I think there's more at play here than first meets the eye, and definitely needs retesting! :-)
We're both in the same boat mate, I expected a seriously one-sided result in favor of the OSC, but left feeling aghast at how good the DSLR did!
I'll definitely have to look at a part 2!
Clear skies mate, and as always thank you for giving your support and thoughts so freely - I appreciate it!!
Amazing video, thank you so much for this testing! :)
Thank you for watching!! I'm glad you liked it :-)
Great stuff Luke. When I first saw this I was very surprised. Maybe cuiv has some good points. I just used your ocs rosette data to use for the first time pixinsight and now I’m an expert! It’s got soo much functionality I’ve not even managed to see yet but I already know it’s going to be more useful than gimp. Also used topaz denoise thanks to you 😀
Hey Ben! - glad to hear you've enjoyed the video, the data, pixinsight and also topaz! That's excellent haha :-D
Thank you for watching and sharing how things have been going!
Clear skies!
Hi Luke,nice test you carried out and good to see the DSLR perform well.The Canon 700D DSLR certainly provided a great image,shame you had to split the test over two nights.I’m sure a further test you mentioned will have the ASI pulling ahead in sharpness and noise as you mentioned.Look forward to a part 2 on this subject,if we can ever get some consistent clear skies for a few nights!
Hey Jon! Thank you very much mate, I do want to do another test for sure, if for nothing else than my own curiosity! :-D
I'm glad that you found it interesting my friend 🙏
As always, thank you for watching and supporting Jon, it's hugely appreciated 👍👍
All this proves is that you have to do more tests...and make interesting videos while doing so. Maybe make an ongoing series where you test with various targets incorporating some of the suggestions from Cuiv, Kamil, etc.; like a DSLRa vs. OSC Fight Club, lol. 👊
I'm glad you included your honest confusion at the results as part of the video. Keep it up, sir!👍
Hey Philip! - I think you're right on the money mate! :-) definitely needs further tests and application of tips 👍👍
I'm glad you liked the video mate, and thank you for leaving a comment! :-)
All the best,
Luke
Brilliant, I’m a fan of using a DSLR for imaging. I’ve had some great results with my Nikon Full frame. Great video Luke.
Thank you so much! - the dslr really pulled it's weight I think 👍👍
Clear skies!
You can still enjoy and achieve great results using a DSLR. That was what I took away from this video man. I'm sure there are other crazy and very specific details, but in the end, it comes down to that. Hope you are well brother.
Hey Isaac bro! - I'm doing great thank you!! I hope you are too :-)
I think that's a nice summary really, there's so many factors at play here that it'd be near impossible to nail it all down after just one experiment! I've just recorded some data for my next part though now, which I hope offers more answers than questions! :-D
Thanks for watching mate, as always! and again thank you for your support!
Excellent stuff, quite surprised at the result, maybe worth trying again in the summer to see if the temperature makes much difference. Also thanks very much for the Topaz discount code, just purchased all three (denoise, sharpen, and gigapixel) for £67 as it's on sale right now and your code gave an extra $15 off!
That's awesome to hear Dave!! That's literally about half what I paid haha :-D Great deal!!
I'll definitely need to revisit this again, though by summer I may have sold the OSC to buy another Mono rig, I'd like to try that again you see!
Thanks for watching mate!
Great video Luke. Without having twin rigs at the same time it's never going to be perfect results. I enjoyed it mate. The humble DSLR can still hold its ground I think either way. My best images have been with a Canon 77d and not my ASI533 believe it or not but that may be my experience level with OSC.
Clear Skies Buddy!
Hey Ben! - I'm glad you liked it matey, I think as you say, without dual rigs there will always be a slight inconsistency but I hope it's still valid enough to be interesting! :-)
I can certainly see how the 77d and your familiarity with it will lead to better images too, half of this game is being comfortable with your gear isn't it! :-)
Thank you for watching mate, and as always, for your support too 🙏
I hope you have a great weekend!
Stirred the pot with this one you did ;)
As always, looking forward to your next one. CS!
Mate you're not kidding haha!!
Thanks for watching :-D
Interesting results. The sensor in the 700d should in theory produce softer images with that scope under the same seeing conditions, and yet it seems that it produced sharper ones. You'll have to let us know what you find out. Thanks for sharing!
Hey Joe! Appreciate your thoughts mate, I'll have to experiment further and try again I guess haha! :-D
Thank you for watching!
Quite surprised at that result mate. I was totally bias towards the OSC before watching and like you im left scratching my head at the result. Great video mate.
Hey there mate! - I really am so surprised, I'm glad I'm not the only one haha!
Definitely needs more testing, maybe in broadband next time and on the refractor! - just need this storm to pass now, such bad weather at the moment!
Thank you very much for watching and sharing your thoughts my friend, and for your continued support!
All the best,
Luke
I have just skimmed the comments, so apologies if I missed it, but not much was considered on dynamic range and data clipping. The 700D at 1600 ISO has about 9 EV of dynamic range where the 2600MC is over 13 EV at 100 gain. I believe what appears to be sharpness may be clipped dark areas. At time 10:43 in your video the core of the Rosette shows nebulosity in the OSC camera but just black in the DSLR, hence my thoughts on DR. The other issue is in camera processing of RAW files verses the OSC FITS files. I would bet the DSLR processor will boast the saturation compared to the OSC processor, but that is just speculation. Lots and lots of variables to consider BUT the bottom line is that DSLR can provide attractive results without spending gobs of money. Good results have more to do with good technique and good seeing verses super-duper equipment. Thanks for the time and effort to make the video, worth watching. Clear skies!
Hey Edward! - Thank you very much for your thoughts on the matter, they were interesting to read! :-)
I'm happy to say a second test with revised methodology has delivered much closer to anticipated results, while still leaving the DSLR looking like a very capable offering indeed for the price!
I hope that you may enjoy part 2 when released if this is something interesting to you! :-)
Clear skies!
@@lukomatico I look forward to it. Most all technology has strengths and weaknesses. The old saying "Horses for Courses" comes to mind. The sensor processors in "land" cameras are tuned to process day (high signal to noise ratio) photos and astro cameras to process low signal to noise ratio photos but there is cross over and all are useful with proper handling and understanding the limits - which is what testing is all about. Besides it keeps us out of the bars (pubs) at night - at least until we get the auto imaging routine down - just don't tell the misses. :) Hun, I'm off to the dark site!
Great work Luke, I have the modded 700D and love it, however I am looking at the moment for a CMOS camera as well :-)
Hey Simon!! - It's a lovely camera isnt it? I've certainly no complaints! - RE: looking for a CMOS, well.. one might be coming up for sale soon haha :P (i'm tempted to try mono again)
Clear skies mate!
Wow I did not expect that! I was primed for a beat down by the 2600MC-PRO, especially since I just purchased the QHY version of this camera (QHY268C). Try gain 0 on the 2600 next time. It looks like at gain 100, your fullwell is down in the 'DSLR' territory of 16500'ish, where as at gain 0 you're up over 50000! Even at gain 0, you'll convert electrons into ADU's at the twice the rate the 700D does at 1600ISO. Most cooled camera users crank up the gain to achieve 'Unity", but the 2600 is already faster than UNITY at 0 gain. This is something I'm curious about trying with mine.
Hey there mate!
Thank you so much for the suggestions, I appreciate it :-)
I too went into this expecting it to be quite one-sided, but damn if I don't love an underdog story!!
I will have to regroup and retest, it's a worthy time sink I think!
Great job Luke, a bit unexpected though, but as Cuiv says, it shows that the good old dslr can still hold its own! Probably like most of us, I started with a DSLR, actually a canon 60DA, (recommended by our friend Mr Trevor Jones)! then I believe you had something to do with me getting a ZWO 2600mc pro! Cheers👍 I love it really ! Thanks Regardless of image quality, my favourite thing with my cooled osc is the fact I can take my darks and flats the next day saying me hours!😀
Keep it up Luke, look forward to the next comparison! Clear skies
Hey Simon! - definitely a bit of an eye opener haha, I fully agree by the way, in terms of ease of calibration then you can't beat a cooled camera 👍👍
I'm glad to hear you are happy with the 2600 of course, I'd hate to think you'd bought one and regretted it!
Thank you for watching, and again for your support mate! 🙏
In addition to what others have said, the OSC camera has smaller pixels and will need to be exposed longer to get a similar SNR. I would expect the OSC to have a "softer" looking image, all other things being equal.
Hey Ryan! The OSC may have smaller pixels, but does have much higher QE, a BSI sensor, lower read noise and lower dark current, which should more than make up for the slight physical pixel size mismatch between the two cams - I believe something went wrong such as the primary mirror or filter itself slightly fogged during the OSC portion of the test, leading to it being a bit of an unexpected result - part two gave a result more in line with expectations, I switched to my refractor for it to remove as many extra variables as possible 👍
Thanks for watching and clear skies!
Great vid
Appreciate it Robin!! :-) Clear skies mate
Interesting comparison Luke with an (un)expected outcome, but ...
Don't forget that an DSLR (or mirrorless) also gets some minor contrast boost and sharpening on the RAW file, Nikon does this, Sony does this a lot and Canon does this very minor, well all brands do that.
So keeping that in mind it is logical to see this outcome. And ofcourse about the noise, you are always better off having a cleaner file to start with.
Thanks for watching and sharing your thoughts Siegfried!! - I totally agree, there's always some internal processing on "RAW" files, great to see though how well the good old DSLR did vs a much more expensive cam! - Part 2 of this series addresses some of the other parts that could have gone wrong in the test also :-D
Hey Luke, I just modded a T3i today and got to thinking. As you noted, you were comparing an older canon dslr to a newer cooled Astro cam. I’m just wondering if it would be a more fair comparison to use a newer canon with the latest sensor technology. I’m not sure how much stock camera sensor technology has improved over the years but it would be interesting to see!
Hey there Robert! :-) Congratulations on the modded T3i! you should have some fun with that over the coming months I think!
I'd love to make another comparison someday if I get my hands on a newer modded DSLR/Mirrorless cam, it's just something I'm not able to do yet as I can't afford to buy one for the video hehe! :-)
Thanks for watching and giving your support!
All the best,
Luke
Very good job indeed, thank you ;)
Thank you for watching!! :-D
Good comparison. And thanks to take the time to do this test. However, as others have said I’d repeat the test on the very same night and same time for each camera around the meridian (say for example one hour for one camera until the OTA reaches meridian and then change the camera and let it image the same object for another hour). That could be more representative, while keeping all of the same equal.
If I may, to me it looks like there’s a flat calibration difference between both sets (take a look at 8:02). The OSC image to the right shows some vignetting that the DSLR image on the left doesn’t show. Maybe it would be worth checking. When I upgraded from a modified Canon T1i to an ASI071MC Pro immediately saw a difference in pre processing was required: the 071 gave better results if flat darks were used, while for the T1i I just needed a mast3r bias to calibrate the flats.
I’ll be looking forward for your next video on this subject.
Regards,
Alfredo
Hey Alfredo!
Thank you very much for the suggestions! :-) I appreciate that, I've applied very similar changes to the methodology for test 2 which is now recorded! safe to say it all went off well on 1 night :-)
I do tend to use flatdarks already for the reason you suggest, normally my images calibrate well but in this case it wasn't quite perfect, possibly due to the limited data pool of lights I had, some may have been contaminated by little bits of cloud contributing to difficulty calibrating accurately :-)
Thank you very much for watching and taking the time to comment!
All the best,
Luke
@@lukomatico Very well, Luke.
I’ll be looking forward to watch the new video when it’s available!
Hi Luke, i did a simillar conparaison on my channel whit a zwo asi071 mc-pro and an unmoded 1100d. I was suprised how people reacted to my comparaison. For my part, the results for the stock t3i or 1100d was horrible. I had mentionned that it was just a comparison of the two cameras to see the difference between a cooled and non cooled camera. Some but people was thinking i was batched dslr cameras for astrophotography but i was not case. So i am i the same game of you. Great video and keep going! From québec canada!
Hey Alexandre! - that's interesting to hear, I'm sorry to hear your comparison maybe got took in the wrong light though!
I'll have to check it out when I get the chance :-)
Thank you very much for watching my friend, I hope you're getting some clear skies over there in Quebec! :-)
@@lukomatico Thanks Luke, keep going i love your videos!!
I had given up imaging when the moon was more than 50%, would appreciate your opi9nion on imaging when the moon is up and is the data worth gathering ?
Hey there Spike! - it's a tough one to answer, if you are shooting with narrowband filters then it's still worth it to shoot, unfiltered broadband is a bit of a different case though, if you are shooting the total opposite side of the sky than the moon is in, then it could still be worth doing for less serious projects in my opinion :-)
I have an old video I made on this very point actually, shooting under the full moon!
I hope that helps mate!
Hi Luke I haven't read everyone's comments so my point have been made but I would suggest where a osc shines is in the middle of summer on a hot night. The noise from a DSLR with ambient temperatures say around 25°c will absolutely destroy an image. Very interesting video Luke and as always well presented 👍
Hey Paul!! :-D I strongly agree mate, on a warm night this would likely look very different indeed! Always worth considering 👍👍
I hope you are well! - thanks for watching mate!
Very interesting Luke the DSLR did very well in comparison I knew there would be more noise with it but the image itself did look better out of the 2, maybe capturing the data over 2 different nights may have affected the outcome? Hmmm I can see a Peltier mod being done to the DSLR now ;-)
Maybe do another test on the same night (if thats possible in the UK) on say a target close to the meridian say 10 or so subs then 10 or so subs after would be a fairer balance?
Sorry waffling on here just trying to come up with ideas but I'm super impressed with the DSLR
Hey there matey! - I agree, the noise was expected, though there was less of it than I thought there would be - the DSLR image did look better overall didn't it!
I'll have to revisit this with another test and give it a proper look again, so confusing and too many questions raised by this first test haha!!
Thanks so much for watching mate :-)
Clear skies!
Interesting Luke, good job. I also have a Baader mod DSLR, but don’t (currently) use a filter. To be honest I don’t know much about filters, what benefit does it bring? Do you have a link to the one you used?
Hey JJ! :-)
The benefit of the filter is to quite literally filter out unwanted light, and only let through the desired wavelengths, in the case of my optolong l-extreme, that's HA and OIII :-)
They have more limited benefits on broadband targets, often unfiltered shooting is preferred there 👍
I hope that helps!
Thank you for watching!
Hey there, I wanted to run your data but i do not seem to find it anymore? Can I receive a link that is still working?
Hey Thomas! I think this data is likely lost now, I'm sorry about that! I had to clear some room on my cloud storage for newer tutorials and it probably got deleted then :-(
My apologies!
Great video. Do you think maybe the fact it was on two different nights that the sky quality may have differed? May have looked good,but could have been some high haze..
Hey Jason!
It could be! - it was just the immediate degradation in star quality between dslr & osc, all within half an hour that made me think it's something else 👍👍
Thank you for watching mate!! :-)
Very Good Comparison, Luke! Its very Clear In the Images!! Between DSLRs and dedicated Astro cam! I would Choose An AstroCam For Sure, Since My Interest lies In Astronomy. But DSLRs are Certainly best For Wide Field Astro and Convenient to use, and affordable Too!! I always wonder If There Were would be any 'Cooled' DSLRs?? Which would have Cooling Inside To reduce Noise! It sound Crazy, But I like The idea :)!
Fantastic video Man,
Clear Skies🔭
People have cooled DSLR's with varying results I'd pop in a link but may get flagged as spam as TH-cam has done in the past so if you just Google cooled DSLR's you should find something, there's even a place that sells them but I cannot comment on how good any of them are 🙂
Hey Avanteesh! Hope you are well mate :-)
As Dumpy Dalek mentions here, you can indeed get cooled, modded DSLR's, but the cost is just about equal at that point to a dedicated astro cam haha!!
I hope to retest and see what else I can learn from this, thank you for watching man, as always!
LOL yeah I forgot to mention the price of them.
Enjoyed the video Luke and don’t really care what the outcome was, just enjoyed watching. Quick question, what do you use to collimate your newt. I just purchased a 130PDS for my Gem 28 mount.
Hey there KK! :-)
I'm glad that you liked the video for what it was, that's actually a really encouraging thing to hear so thank you! 🙏
As to collimation, I use a 2" laser from Farpoint astro, and a 2" Cheshire also from the same brand, really top quality gear 👍👍
I really hope that you like your 130pds, they are a lovely scope and supremely capable!
Thank you again for watching :-)
@@lukomatico Cheers mate
Interesting test, but I think that DSLR RAW files might have an automatic contrast curve applied to them by the camera, while the OSC camera might be linear. You should have tried to play with contrast to equalize the two images. Then you can compare them.
Thanks for the feedback Lou! - There were a lot of ways to approach a test like this I guess, inevitably adding more steps introduces more variables though, so I opted to keep things as simple as possible during part 1, - in part 2 I did alter some aspects of the test in order to improve the quality of the test result, but still try and keep variables minimized :-)
Clear skies!
One more thing to consider: maybe the DSLR image looks so much sharper is because it is more noisy. I mean, if you sharpen an image in Photoshop, it also adds noise. So in general more noisy appears to be sharper. I’m not saying it’s the only factor here but it might contribute to the overall impression
Hey Kamil! Good question my friend, it could indeed be partly the case! I think the difference is perhaps too large to be that alone, but it could be a factor indeed! 👍👍
Thank you so much for watching and sharing your thoughts mate! :-D I appreciate your time!
are those two camera have same CMOS sensor？
Hey there Charles! - they do not share sensor tech, no - it's an apples to oranges comparison but still fun! :-)
Thanks for watching!
Hello . Two thoughts , what were the distances from the Filter to the Sensors for both cameras and was the backfocus set for each camera and sensor . A mil or two might account for the sharpness/softness . Maybe ? Great Video once again . Cheers./SRK
Hey Scott! - Great questions mate! thanks for them :-) the distance from filter to sensor was the same for both, as I left the filter on the end of the coma corrector barrel, backfocus for both was 55mm exactly also :-)
I hope that helps!!
Thank you for watching :-)
Again if you consider possible slight misting on the OSC due to the colder night, and the moon glow, maybe this could account for difference. Always wondered if you can calibrate reduce noise rather than spend another 2000 pounds (2700 usd) for astronomy camera and filters (astrodon) 2000 pounds extra.
Hey there Bill! Thank you for the possible explanations matey, I appreciate it! :-) It certainly seems with newer noise reduction methods you can calibrate out a metric ton of noise, especially Topaz and the like!
Thanks so much for watching!!
Do you think this could be due to the moon being closer to the subject when shooting with the OSC ?
It's possible John! but I can't say for sure - it needs a retest for sure :-)
All the very best!
Luke
Could it be that DSLR is a more refined and developed camera? I shoot with a modified dslr and am curious myself to see the answer
Hey Scott! - Very interesting suggestion mate, definitely Canon can throw more money at this than ZWO can, and there's certainly more than just a nice sensor at play in the DSLR, what with it's DIGIC processor onboard! all very valid arguments, hmm... this needs a re-test lol :-D
Thank you for watching!
I’d love to see a comparison between my Canon Ra and your ASI2600. Both dedicated Astrophotography cameras, one cooled one not. One good for day time photography one not.
Hey Richard! - I fully agree, that would have made for an excellent and more fair comparison! :-)
I'd love an RA but just can't afford one in truth haha! :-D
Thanks for checking the video out!
It just shows Luke..you don't have to spend a fortune to take great images ,a DSLR camera can get great results especially if you are are novice like myself. It makes me wonder if it's worth the jump up to a dedicated camera, I have a planetary camera which is fantastic...but do I need to get another deep sky one... interested in your next vid. Out of interest my 650d is as of now unmodified, love to see a shot with stock camera.....keep em coming.
Hey Peter! - I'm glad you liked the video mate, it was a bit of an eye opener for me!
Definitely a modded dslr can pull it's weight, especially in colder climes! - I'll have to revisit this I think - too many questions raised haha!
Thank you for watching :-)
This video interests me because my QHY 8L is no longer managed well by the programs. It disconnects too much and the temperature is not stable. QHY technicians connected via teamviewer but nothing special. The next morning they told me that their Stellarmate had managed to fix it. Too bad that the day before not.
I have had the MPCC Mark III 2 "Baader for two years, and I was only using it as a coma corrector without the M48 ring. I decided to mount it to use my Canon, but suddenly it unscrewed and the camera fell on the ground! I bought an M48 ring on Amazon and it works.
How long do you pause between shots?
Hey Paolo! - sorry to hear your qhy8l is giving you trouble :-(
On the note of pauses between exposures, I let it have 2 seconds between in the plan I believe :-)
I hope that helps a bit, and thank you for watching!
@@lukomatico thx :) Even with the 2 second DSLR?
The same pause yeah :-) just to allow the camera a moment to clear it's frame buffer 👍👍
@@lukomatico I thought longer as a break to cool it down more ;-)
Hey Luke - Well I wasn't expecting that mate. I've read thru a few comments and suggestions but I was feeling a bit like you, a bit puzzled by this one. Like you say maybe on another night to do the same test and see if you get similar results.
Hope you're going well pal.
Ollie.
Hey Ollie! Thank you mate, I think there's a lot of conclusions being drawn a bit hastily here in the comments haha, it was seeing, it was this, it was that.. Only I was actually there though, and I'm experienced enough to say both nights were extremely similar! Definitely more is at play here and I aim to repeat it to try and find out exactly what! 👍👍
Thanks again for watching dude! I hope you are well :-D
@@lukomatico Agreed pal you never know the full story unless you're there doing it. I think sometimes the downside to social media in general is everybody's need to be "right" lol. One of the reasons I'm not on twitter. I'm sure you'll get to the bottom of it mate👍
It could be different seeing in those two nights and maybe the Moon makes more of a difference than we think. But that's a very surprising result.
Hey there Lyaphine! - I agree that seeing could make a pretty big impact, I've just looked at the last sub from the dslr, and the first from the OSC which were both taken on the same night and within half an hour of eachother, and there's still a sharpness advantage for the DSLR I think! something is very odd indeed, needs more testing!
Thanks for watching :-)
Very interessting experiment. I think, the Canon photo only appears sharper because it is noisyer. In the further processing you should be able to sharpen the ASI photo at least as much but with less noise around than you would be able to do with the Canon photo.
The tighter stars in the DSLR photo might be caused by the fact that with bigger pixels, you are better sampeled. With the ASI 2600MC you are a bit oversapeled, which blows the stars.
This is my understanding of the really unexpected results.
CS Christian
Hey Christian! - Thank you so much for watching :-) I appreciate the hypothesis!
I've since taken a part 2 to this which is nearly ready to be released, which more clearly shows the advantage of the OSC over the DSLR! - I think it seems most likely now that the auto-focuser missed focus with the OSC marginally, coupled with potentially a light misting of dew on an optical element (not tracked down what) reducing and scattering the incoming light.
The re-test was done with my Esprit 120, which has proven to be a more suitable test platform it seems :-) I hope you may agree when part 2 is released for your consideration!
Thank you so much for watching!
All the best,
Luke
I think it would have been better to just edit both images individually.
Since the DSLR has more noise, but also more contrast, it suggests that the OSC still has some "room to manoeuvre".
Kind of like (but obviously not the same as) the way jpg images look better than RAW images when they both come out of the camera.
It's also a bit like hopping into 2 different cars, and assuming one is faster because the maximum speedometer reading is higher, without actually driving them to test it out.
It would probably have been better to either get both images looking the same (colour and sharpness), and then compare the noise levels; or else get the noise levels the same, and then check the quality.
If that makes sense?
Totally appreciate what you're saying mate yeah! I could/should have added that as an additional segment, then it'd be pleasing to both parties :-D
Thanks for the feedback!
There is only one way to compare any (!) Equipment:
Every(!) other part, but the testet part needs to be 100% equal.
You need to set both cameras with two identical optics one one astromount. Both need to capture at the same time the same sky. And both cameras need to be set to unitygain and need to exposure for the same time.
Than you can compare one single image of each camera.
But: This is not a "hate-comment". Over all it's interessting and you did lots to get good results.
Hey there!! :-) Thank you for watching!
They were both set to 'optimal' gain/iso settings, and the exposure times were the same, as was total exposure :-)
I agree that it may produce a more valid test, but certainly not realistic to achieve really at this equipment scale - can you imagine side-by-side 10" newtonians! :-D
It also would have it's own set of new variables introduced, as in - are the optics and collimation of both scopes perfectly matched? would heat leaving the tube of one scope, rising past the other scope, ruin the other scope's seeing somewhat? etc, etc.. - I did my best given the conditions, and still feel it's a largely valid test, but I will indeed be doing a retest!! :-)
Thanks so much for sharing your thoughts and watching!
(p.s, if you are interested to compare, I have added a single sub from each camera, the last sub from the DSLR session, and the first from the OSC session, less than half an hour between the shots :-) )
very interseting Luke. I wonder.... I have an old OSC APS-C CCD camera with 7.8 micron pixels. I wonder how it compares to a 3.76 micron CMOS camera..
Hey Jason! - 7.8 micron pixels.. I'm guessing a qhy8l or some such? it's a good question mate, I'd guess that it'd gather a decent amount of signal on any given scope when compared to a much smaller pixel camera, simply due to those massive pixels even if the sensitivity isn't as good! but the downside is, for any given scope again, it'll be sampling more coarsely, bad for detail, good for signal! :-)
I really like my Canon 6D + drizzle, it gives me the ability to print big, possibly 12 feet by 12 feet canvases!
That's pretty crazy! - all I can say is that'd be one heck of a printer, and I wouldn't like to buy more ink for it when it runs out!! 😂😂
What about anti-aliasing? Is that possible?
Hey Garnett, I hope you are well! - I think there's no low-pass filter on either camera as far as I am aware, but that would have explained the softness for sure!!
Thank you very much indeed for watching! :-D
@@lukomatico indeed. Interesting comparison. My first instinct is something on the hardware side. I have zero doubt you can judge the quality of sky. I’m very interested in knowing the why of this outcome. Tests and comparisons are always super interesting to me. Thanks for posting. I’d love to check out the data but it will be ten days before I return from the gulf. Perhaps you can look at a sub from the dslr and inspect the metadata. It’s possible a hint might exist there.
Hey Garnett!
I think your instinct is likely right on the mark, I suspect there's some kind of in camera processing that's just baked-in and cannot be turned off, but actually works rather nicely!
Definitely further experiments are needed, it's good to hear you like this type of content! :-)
Thank you again for your help, and safe travels back home! 👍👍
With today’s excellent dslr’s and mirrorless cameras cooled OSC is the biggest waste of money I did in astrophoto hobby. I wish I had dropped it and go directly to mono. I still have and use the dslr though.
Hey Barbaria! - I'm sorry to hear that going cooled OSC was a letdown for you! I think they certainly do still provide nice benefits over DSLR/Mirrorless cameras for astrophotography, especially in warmer climates I guess, but also there's drawbacks to going dedicated OSC for people interested in multi-use cameras, e.g astro & daytime use :-)
I hope the next test shows us more about what can be expected from both!
Thanks for watching!
Hahaha, Luke! I’ll keep my old Canon then. Cheers!
I don't blame you Enrique!! haha :-D Definitely this needs more testing!
@@lukomatico agree! Have an awesome rest of the weekend!
@@enriqueboeneker Thanks!! You too :-D
Dual rig needed Luke same scopes same time 👍
I agree mate, that would be a cracking way to do it! I just don't think my pockets are deep enough haha! :-D Thank you so much for watching my friend!
Don’t understand why you don’t compare single frames shot during the same night. Maybe take 5 each so you get the job done quickly and fairly. Good try though!
Hey Giuseppe! Great idea mate :-) I've actually just uploaded to my drive the last image from the dslr, and first image from the OSC, they could be compared with more validity perhaps?
Thank you so much for watching!
Speaking of uncooled cameras in a colder season. What is the lowest temperature outside that you would set your gear up in? My guess is your a winter soldier.
Hey mate! haha, you've got me - Winter Soldier! I love it :-D
Generally speaking, if it's clear - I'll set up and try no matter how cold, I may draw the line at something like -10/-15 though as cables/connectors can become brittle at those temperatures!
Clear skies mate, and thank you for watching!
I'd be careful if trying to cool below the dew point, the temperature at which water starts condensing (or, freezing) on a cooled surface, e.g. the focal plane. It might be possible to set up a gentle purge using dessicated air, or compressed dry air, or something, that has a dew point in the -20 or -40 degree range. Then you can cool the array to that temp without fear of condensation. I'd want to use air or something close to air, to avoid the refractive turbulence of different gasses mixing. Dry climates and/or winter air has a much lower dew point than humid, muggy summer air.
Hmmm.....Astrophotography throws you a curve ball, who would have thought that? Note: Sarcasm meter is peaking far into the red zone... Lol...
I'm with just about everyone on this one, the OSC should have spanked the DSLR. Someone on a higher pay grade then me will chip in with some knowledge on the what's going on here. Looking forward to hearing what others think.
Hey Chris! - haha, I couldn't have put it better mate :-D Astro is full of the unexpected I guess! I hope to dive further into this in another video perhaps!
Thank you for watching :-)
Quantum Efficiency.
Hey there! - the quantum efficiency argument would strongly lean in the favour of the OSC camera, but the results themselves speak a different argument so far! :-) there must be more at play.
Thank you for watching!
@@lukomatico Because the quantum efficiency is higher it is capturing more signal. My approach would be to match QE with exposure time to do the test as it is capturing more data including extra light from stars possibly causing them to blow out.
That would not explain the smaller non saturated stars also being softer though, I appreciate the suggestion though!
wow sell me your dslr lol. much prefer the contrast and colour depth. your shock was for all to see
Haha! Glad you liked it Andre! :-) I hope you'll enjoy part 2 also when it's out, I think it was a better comparison overall this time 👍👍
Wot DSLR mate
It was a modded Canon 700D matey! Cheers for watching :-)