This is one of the best and simplest videos on explaining why you need a focal reducer and the exact numbers you need to achieve it. Great video as always!
Dang, I remember when you said on Reddit that you'd be uploading this video soon, and now it's already here. Time sure does fly... but thanks for the informative video, Tiago!
Yeah i decided to upload it faster because I'm using a lot this technique on this galaxy season. It's working well. Having the video it's easier for everybody to understand what I'm doing.
ive been wanting to start astrophotography since 3 years ago and later quit when i was told it wasn't possible with a dobsonian. I later ran into your account and immediately fell in love with it. Your channel is the reason i cant wait to open my computers on Fridays after school. Keep up the good work man .
An interesting approach, I have a 0,95x reducer/corrector, never looked on it this way. The goal was to get rid of coma, but the deep sky targets are really small, so I cropped them to make larger :)
I spent -$250 with shipping to have my 6" primary and secondary mirrors re-aluminized to 97-98% reflectivity, but they also did a mirror check 1st for free and my mirror had very little aberration. What little there was they reconfigured my scope for another $128 and it is near perfect in wave and knife test. 97% reflectivity is hard to see by eye over factory 92-93%, but a camera picks it up. I took single 1/200th second pictures of binary Mizar at 234x with a 3.2mm ED eyepiece and it was near perfect except for some turbulence in some pictures, but others were two perfectly round blue stars. 8" mirrors are more expensive, but not terribly so at Spectrum for $130, but he doesn't do reconfigures. edit; It did not do that before, was always some minor spikiness.
@@DobsonianPower Yes I Know, but It wouldn't Really make A Significant Change in the Image Right? Otherwise Bad Seeing With Short Fl And Big pixels Can Help To Get You Right Sampled 😛
Another great video. I'm thinking of getting this reducer for my F5 10" gso dobsonian and the sv406cc (same sensor as the asi294). I only want to run it at 0.8x reduction. Have you ever used yours at 0.8? I'm wondering if the coma will still be present when imaging larger dso's like the Orion nebula.
The minimal reduction you can apply with the zwo 294 and this 2" reducer is 0.75x with the reducer the closer possible to the sensor. To reach 0,8x you would need to replace the 10mm black T2 ring for something thinner. I did it but with an adapter that will not enter into the focuser, so, not an option. Yes you may see coma that's why i use this video trick to get rid of it.
I built a 6" dobson f550(f3,8) GoTo . I'm an abs.beginner and I would try to take some pictuter . Can you suggest me a not much expensive model of camera to start with EAA ? Thanks for your instr.videos 😊👍
I use and strongly recommend this ZWO ASI294MC camera: 🇺🇸amzn.to/3nBiMiP but you have cheaper ones but the sensor will be smaller. The zwo 224 i have is cheap and small but you can do this with it: th-cam.com/video/Gc2CfBHfRKM/w-d-xo.html
Good question. A coma corrector will not turn your telescope faster but may work screwed to the focal reducer. It will depend, in my 8 inch it worked fine together but in my 6 inch it did nothing so i decided not to use it. You have to try and see what happen. I showed it in another video: th-cam.com/video/H6W2K8tW0qg/w-d-xo.html
Grand Bravo pour cette très intéressante et utile vidéo . En effet j'utilise un Nikon D5200 monté sur mon N203/1000 GOTO j'obtiens de belles nébuleuses planétaires M57 M27 ou amas M13 mais entourées après empilement sequator uniquement de très peu d'étoiles ( grosses et baveuses).Même chose avec M31 où j'obtiens le cœur mais pas assez d'étoiles !! S'agit il de la Coma ? Dois-je réduire la focale comme vous ? J'ai aussi une camera bresser full HD deepsky 1;25.que j'utilise pour observer les planètes. Serait-elle meilleur pour le ciel profond ? Un grand merci pour les conseils
I am new to this field. But I have been studying astronomy. I want to buy my first brand new telescope. I am interested in Dobsonian telescope. The person whom I'm buying the telescope from has given me two options . Meade flexible Dobsonian 10 inches (726$) or 12 inches(1050$) or SkyWatcher flexible Dobsonian 10 inches (750$) You are a very professional person so could you please advice me on which is the better telescope. Very Kind.
the larger the aperture the better. if you can handle and store a 12". i have one and love it. If you want to take pictures of many objects you need an equatorial platform or a goto telescope.
Thanks Tiago for these very nice ideas . I've just bought a cheap 2" 0.5X GSO Reducer. I believe I won't be having so good results as you, using the 8" F/6 + ASI224MC because I will be using a shorter focal ratio (F/5) and a larger sensor (12mm diagonal). Native pixel scale 1.6 ArcSec per pixel. With focal reducer over 3 ArcSec per pixel (undersampled). Do you think I will still have an usable central area? Thanks
I have great news for you. I'm using now the same telescope as you, the same camera and reducer and it's working GREAT!! I'll be using from now on this set up as the beginner set up on my live streams. Do this: the camera+M42 to M48 adapter+10mm spacer+reducer and it will give you 1.098 arcsec per pixel and a nice image almost without any coma.
@@DobsonianPower Thanks Tiago, but unfortunately I didn't explain myself in a clear way. My set up is a bit different...ASI482MC + GSO 0.5 FR (+ GSO CC) + newton 150/750 + HEQ5. So the main difference (most relevant factors) between your beginner setup and mine is F6 vs F5 and 6mm diagonal/3.75 pixel size (224) vs 12mm/5.8 pixel size (482). So it seems I will be having worse results than 224 in terms of aberrations but better than 294. Am I thinking correctly? Do you think the cheap focal reducer can help me in smaller and fainter details? Thanks again
@@JediScp You still can do it but at a smaller field of view. Do this: M48/M42 adapter 4mm + focal reducer will give you a total from sensor to the FR lens of 16,5mm (6,5+4+6) and a 1,886 arcsec/pixel and you'll be working at f/3.2 and at the "good" range of image scale. If you have more doubts i explain you in the next live stream, it's easier to show. Also try with and without the CC because it can change things, have to try it.
Hello Tiago, when I add the reducer to my 8 inch skywatcher with the zwo 224MC...I see on my screen my mirror from my scope. Is there anything I can do for this? I guess I need to increase travel space for the focuser?
@@hondvantrond should not. Send me a picture of everything in the focuser and what f ratio is your dob to my email so i can analyze better where's the issue. Also a picture of the camera with the reducer.
@@hondvantrond i answered your email with the picture you sent me. I see that you don't have the reducer near the sensor and you have to place it near, otherwise it will not work.
![เกิดใหม่ทั้งทีก็เป็นสไลม์ไปซะแล้ว ซีซั่น 3 - ตอนที่ 70 [ซับไทย]](http://i.ytimg.com/vi/IbBEqbse4Oo/mqdefault.jpg)
And if you want to know the EAA basics: th-cam.com/video/nLwkCaFbsxQ/w-d-xo.html
This is one of the best and simplest videos on explaining why you need a focal reducer and the exact numbers you need to achieve it. Great video as always!
Thanks Vang Vong. In my next live stream, after the Moon is gone, i will break down this even more. It's working so well for me that it's worth it.
Dang, I remember when you said on Reddit that you'd be uploading this video soon, and now it's already here. Time sure does fly... but thanks for the informative video, Tiago!
Yeah i decided to upload it faster because I'm using a lot this technique on this galaxy season. It's working well. Having the video it's easier for everybody to understand what I'm doing.
ive been wanting to start astrophotography since 3 years ago and later quit when i was told it wasn't possible with a dobsonian. I later ran into your account and immediately fell in love with it. Your channel is the reason i cant wait to open my computers on Fridays after school. Keep up the good work man .
Thanks Patel. The Dobsonian can give much more than many people usually think. 👍👍
love your channel 👍
Thank you!
Very useful content, thank you
Genial la recomendación Tiago. La voy a aplicar en mi próxima sesión 😊😊😊
Vale. Luego me dices como te ha ido Miguel. 👍💪
Thanks for the great information Tiago. I'll have to try it.
Hi Ray. Worth it.
An interesting approach, I have a 0,95x reducer/corrector, never looked on it this way. The goal was to get rid of coma, but the deep sky targets are really small, so I cropped them to make larger :)
Like i used to do. But this way we get it at lower focal length, very nice
Thank you.
Hey Ron, thanks! Have a nice weekend.
@@DobsonianPower You too. 😊😊
I spent -$250 with shipping to have my 6" primary and secondary mirrors re-aluminized to 97-98% reflectivity, but they also did a mirror check 1st for free and my mirror had very little aberration. What little there was they reconfigured my scope for another $128 and it is near perfect in wave and knife test.
97% reflectivity is hard to see by eye over factory 92-93%, but a camera picks it up. I took single 1/200th second pictures of binary Mizar at 234x with a 3.2mm ED eyepiece and it was near perfect except for some turbulence in some pictures, but others were two perfectly round blue stars. 8" mirrors are more expensive, but not terribly so at Spectrum for $130, but he doesn't do reconfigures.
edit; It did not do that before, was always some minor spikiness.
Great Video! My ASI 224mc @650mm fl. Is good Sampled at 1.2 are second perpixel!
That's it. And playing with the FR distance is the way to do it.
@@DobsonianPower alternative, You can Use the Drizzle Function In processing software to reduce pixel size And Bring out Resolution
@@avt_astro206 alternative but only for AP not for EAA which is what i love.
@@DobsonianPower Yes I Know, but It wouldn't Really make A Significant Change in the Image Right? Otherwise Bad Seeing With Short Fl And Big pixels Can Help To Get You Right Sampled 😛
@@avt_astro206 seeing indubitably has the last word
Another great video. I'm thinking of getting this reducer for my F5 10" gso dobsonian and the sv406cc (same sensor as the asi294). I only want to run it at 0.8x reduction. Have you ever used yours at 0.8? I'm wondering if the coma will still be present when imaging larger dso's like the Orion nebula.
The minimal reduction you can apply with the zwo 294 and this 2" reducer is 0.75x with the reducer the closer possible to the sensor. To reach 0,8x you would need to replace the 10mm black T2 ring for something thinner. I did it but with an adapter that will not enter into the focuser, so, not an option. Yes you may see coma that's why i use this video trick to get rid of it.
Fantastic video. So helpful. Many Thanks.👏👏👏👏👏👏👏👏👏
Glad it was helpful! Thanks a lot!
Hello ,
Why my telescope shows double image? Do you recommend any solution for this? Or do you know any possible reasons for this issue?
How's that? With a camera?
I built a 6" dobson f550(f3,8) GoTo . I'm an abs.beginner and I would try to take some pictuter . Can you suggest me a not much expensive model of camera to start with EAA ? Thanks for your instr.videos 😊👍
I use and strongly recommend this ZWO ASI294MC camera:
🇺🇸amzn.to/3nBiMiP but you have cheaper ones but the sensor will be smaller. The zwo 224 i have is cheap and small but you can do this with it: th-cam.com/video/Gc2CfBHfRKM/w-d-xo.html
@@DobsonianPower thanks👍😊🤗
I want to purchase this reducer but I already have a coma corrector, can i use it as a coma corrector add-on? not sure if it will work.
Good question. A coma corrector will not turn your telescope faster but may work screwed to the focal reducer. It will depend, in my 8 inch it worked fine together but in my 6 inch it did nothing so i decided not to use it. You have to try and see what happen. I showed it in another video: th-cam.com/video/H6W2K8tW0qg/w-d-xo.html
Grand Bravo pour cette très intéressante et utile vidéo . En effet j'utilise un Nikon D5200 monté sur mon N203/1000 GOTO j'obtiens de belles nébuleuses planétaires M57 M27 ou amas M13 mais entourées après empilement sequator uniquement de très peu d'étoiles ( grosses et baveuses).Même chose avec M31 où j'obtiens le cœur mais pas assez d'étoiles !!
S'agit il de la Coma ? Dois-je réduire la focale comme vous ?
J'ai aussi une camera bresser full HD deepsky 1;25.que j'utilise pour observer les planètes. Serait-elle meilleur pour le ciel profond ?
Un grand merci pour les conseils
Yes, you could be Oversampling. I never used DSLR to imaging. The best option is a dedicated astro camera like the ZWO cameras.
@@DobsonianPower should I buy a focal reducer like you from 5 (200/1000) to 4 in order to ameliorate the star's shape ??
@@samiblidi9510 May work but I don't know how it will work with that camera. I just know with astro cameras, sorry.
I am new to this field. But I have been studying astronomy.
I want to buy my first brand new telescope. I am interested in Dobsonian telescope. The person whom I'm buying the telescope from has given me two options .
Meade flexible Dobsonian 10 inches (726$) or 12 inches(1050$)
or
SkyWatcher flexible Dobsonian 10 inches (750$)
You are a very professional person so could you please advice me on which is the better telescope.
Very Kind.
the larger the aperture the better. if you can handle and store a 12". i have one and love it. If you want to take pictures of many objects you need an equatorial platform or a goto telescope.
Thanks Tiago for these very nice ideas . I've just bought a cheap 2" 0.5X GSO Reducer. I believe I won't be having so good results as you, using the 8" F/6 + ASI224MC because I will be using a shorter focal ratio (F/5) and a larger sensor (12mm diagonal). Native pixel scale 1.6 ArcSec per pixel. With focal reducer over 3 ArcSec per pixel (undersampled). Do you think I will still have an usable central area? Thanks
BTW I also have a GSO CC....
I have great news for you. I'm using now the same telescope as you, the same camera and reducer and it's working GREAT!! I'll be using from now on this set up as the beginner set up on my live streams. Do this: the camera+M42 to M48 adapter+10mm spacer+reducer and it will give you 1.098 arcsec per pixel and a nice image almost without any coma.
👍👍
@@DobsonianPower Thanks Tiago, but unfortunately I didn't explain myself in a clear way. My set up is a bit different...ASI482MC + GSO 0.5 FR (+ GSO CC) + newton 150/750 + HEQ5. So the main difference (most relevant factors) between your beginner setup and mine is F6 vs F5 and 6mm diagonal/3.75 pixel size (224) vs 12mm/5.8 pixel size (482). So it seems I will be having worse results than 224 in terms of aberrations but better than 294. Am I thinking correctly? Do you think the cheap focal reducer can help me in smaller and fainter details? Thanks again
@@JediScp You still can do it but at a smaller field of view. Do this: M48/M42 adapter 4mm + focal reducer will give you a total from sensor to the FR lens of 16,5mm (6,5+4+6) and a 1,886 arcsec/pixel and you'll be working at f/3.2 and at the "good" range of image scale. If you have more doubts i explain you in the next live stream, it's easier to show. Also try with and without the CC because it can change things, have to try it.
Hello Tiago, when I add the reducer to my 8 inch skywatcher with the zwo 224MC...I see on my screen my mirror from my scope. Is there anything I can do for this? I guess I need to increase travel space for the focuser?
You need to place the reducer NEAR the sensor. Did you?
@@DobsonianPower Yes I did. But I now realize that I'm using a 1,25 reducer. Would that make a big difference?
@@hondvantrond should not. Send me a picture of everything in the focuser and what f ratio is your dob to my email so i can analyze better where's the issue. Also a picture of the camera with the reducer.
@@hondvantrond i answered your email with the picture you sent me. I see that you don't have the reducer near the sensor and you have to place it near, otherwise it will not work.