Here is how I collimated my GSO 8 inch Classical Cassegrain: 1) I sighted through the focuser using any of the available tools. If the secondary mirror was centred within the brighter lit primary mirror outline I left it alone. 2) If the spider vanes appeared uneven I proceeded to adjusting the primary mirror. 2) The primary mirror can only be adjusted on a star , preferably a bright one, centred in the fov of an eyepiece (medium to high power) on a mount that is tracking. 1) Loosen the 3 small hex screws (3mm) at the back of the tube. These are the locking screws 2) Look at the pattern of the out of focus star in the centre of the ocular 3) Tighten or loosen any of the larger screws (5mm-mirror tilt) at the back of the tube. Look at the effect this has on the out of focus star. If it worsens it either do the opposite procedure -loosen or tighten or go to another tilt screw. Make small adjustments and look at the effect on the star. Last night I had extremely flared stars and Jupiter's disk was blurry. I had relied on daytime collimation using the right tools are greatly worsened the situation. Within less than 5 minutes my flared stars assumed their round shapes with the dark spot of the secondary mirror centred in the bright outer ring of the out of focus star. After you have achieved collimation gently tighten the locking screws. My secondary mirror, luckily was not out of alignment. I would not want to be challenged with that problem. I am certain that the primary mirror of a Classical Cassegrain cannot be aligned unless performed on stars. The tools advertised by Starizona are too expensive and a waste of money$$.
Excellent! I just got my TS-Optics 8" Richey-Chretien telescope. It looks very alike the classical Cassegrain. This is helpful info. Thank you very much. :)
We all appreciate the hard work you do in making these detailed which are extremely helpful in educating those of us who are new to the hobby... But could you please adjust your audio levels when dubbing in the music.... My neighbors are complaining...lol
@@AstroForumSpace And thank you again for all the hard work you do.. Your videos have helped me enormously in deciding which way I think I want to proceed and therefore what gear to spend my cash on..
I have a question, have you perhaps been able to find out how important the distance between the two mirrors is? When I bought my Omegon CR 153 used, the Jupiter satellites were perfectly round, but after cleaning the main mirror I had to replace everything adjust and since then the satellites have been more like triangles. I don't even know what to do anymore, I watched a lot of videos and found the right path for myself. I don't have an interface on the eyepiece that I could adjust the angle.
After making this particular video, I had the same issues and I returned the telescope. To properly collimate a classic RC, you'll need a specific laser collimator and there's a challenging collimation procedure. Astroaddict has a great video that explains how to do it: th-cam.com/video/TItMxGqwipk/w-d-xo.html I moved on to buying an Edge HD (modified SCT) which is much easier to collimate, but more expensive.
Hi Wido!! I am a devote fan of You channel and I have The sale tuve, but I cant find information about how clean the mirrows, do You have some links or data about it? I Will really apreciate. Regards from México!
Hi there, thanks! perhaps this helps: www.skyatnightmagazine.com/advice/how-to-clean-a-reflector/#:~:text=Fill%20the%20plastic%20bowl%20with,mirror%20surface%20at%20an%20angle.
I have the same telescope, gought at TS germany too, and collimation is very bad. You're absolutely right when you say there are plenty of video or info, but non as clear as your. Now I'm collimatin in the daylight, as soon as the fog is gone I would check on the stars as well. Just one question regarding the star check, in the first case the oval star requires a little adjustment of the primary. But you do an out of focus as big as fo the test of the secondary? Don't know if I'm clear
Hi Marco, I think in most cases, very minor adjustments of the secondary mirror should be enough. TS told me the primary is almost always correctly collimated. I became frustrated with this telescope and returned it to TS and replaced this one with a Celestron Edge HD. much easier to collimate, but more expensive.
Hi... Thanks for the video. I am planning on getting a 8 inch classical Cassegrain myself. I would really appreciate if you can make a video of capturing a planet to show its capabilities . kind regards from India.
@@AstroForumSpace I used a 5x Barlow on the GSO f/12..I think it is the same Classical Cassegrain you have but different brand name, but the image quality deteriorated. Am I exceeding the magnification maximum at f/60? My camera has 6.9 micron pixels and 720x640 resolution.
Looks like a little bit more circumstantial than with a standard newton and a collimation laser. But perhaps the correct collimation is kept for a while?! I need to collimate really each time before usage and the laser always shows an essential decollimation... And: even with laser collimation done, the "de-focused bright star"-check does not show a complete symmetrical picture (but photo looks ok; not like done with decollimation)...
@@AstroForumSpace Got clear sky yesterday after long and took it out for a proper observation session.. its a great step up from my 6 inch F5 newt.. though a bit on the heavier side for my CEM25p.. works great for planetary and visual. 😀
Very helpful as a guide to what's required. From what you are saying though it seems its not meeting your expectations in terms of pin sharp focus etc. I'm wondering if there's also an issue with the actual distance between the secondary and primary mirrors 'one to the other' - not just 'tilt' or rotational offset around and across the focal axis? In a few days (depending on the autumn weather we're now having to contend with (Western Europe) ... I'll be following along the same path :-) ) There seem to be other collation assistance devices - so not sure which is the best ... purely optical, or with an inbuilt laser? (In theory a Classical Cassegrain OTA should be 'easier' to collimate compared to an SCT, as there's no corrector lens in addition to the primary and secondary mirrors.)
Thanks for this video! Most channels suggest purchasing a Howie Glitter laser at approx $300 with the concentric holographic rings. I only paid $300 for the RC scope to begin with! Thanks for posting a more affordable approach! Can you achieve columnation with your Cheshire method that is close to the laser method?
Hi Robert, I would like to say yes, but unfortunately, that's not the case :-). Hope this helps, I did get a better view after this collimation procedure.
May I put two questions ? 1. How do you cope with your neighbours light pollution?. I suppose that when they see you out at night they will not go and switch of the lights.... 2 when you are doing low angle shots, have you had complains from the same neighbours that you are piking on their houses? Just kidding 3 do you use light pollution filtering 4 why did you not bought a collimating kit?
Wow... get rid of those allen screws on the secondary! One little "Opps!" and the allen key is bouncing off of your primary mirror. Try www.bobsknobs.com/ I looked up your scope and it is not listed but if you call or email him I bet he will have something for you.
The secondary on on a CC is not adjusted like a DOB the secondary is adjusted by using a Cheshire looking thru the back.So no danger of dropping on the primary mirror.
A update to my previous post. A Cheshire is the way to go. The alignment procedure is straight forward and takes just 10 minutes maybe more the first time. Just got mine and it is after all just a reflector. A Orion cc6.
I will now update my previous post. Align the primary as good as possible, after that use a laser just like you use on a DOB for the secondary and you are done. Takes a few minutes. It is very easy, DOB users do it all the time. Super easy . So now that you took it back you are missing out on the main benefits of a CC. You adjust the primary FIRST. The instructions that come with these telescopes are just a lot of nothing when it can be adjusted like a BOB. Remember it is just 2 mirrors no big deal.
@@ohwell2790 I do my collimation on my GSO 6" (the one shown here is the GSO 8") with a Baader laser collimator, held central in the focuser with an Orion centering 1.25" lens holder. Looking down the OTA from the front, I can just see the circle on the secondary. I then adjust using the rear allen key bolts of the primary mirror to get the laser in the centre of the circle. Then tighten up the primary mirror bolts. Next adjust the secondary mirror to shift the returning laser spot into the centre of the display plate on the laser itself. To doubly ensure the laser is seated properly, my RC OTO is face down on the HEQ5, so gravity is evenly seating the 1.25" holder and the Baader laser collimator. Does it work - yes it does. Takes about 5 - 10 minutes.
Here is how I collimated my GSO 8 inch Classical Cassegrain: 1) I sighted through the focuser using any of the available tools. If the secondary mirror was centred within the brighter lit primary mirror outline I left it alone. 2) If the spider vanes appeared uneven I proceeded to adjusting the primary mirror. 2) The primary mirror can only be adjusted on a star , preferably a bright one, centred in the fov of an eyepiece (medium to high power) on a mount that is tracking. 1) Loosen the 3 small hex screws (3mm) at the back of the tube. These are the locking screws 2) Look at the pattern of the out of focus star in the centre of the ocular 3) Tighten or loosen any of the larger screws (5mm-mirror tilt) at the back of the tube. Look at the effect this has on the out of focus star. If it worsens it either do the opposite procedure -loosen or tighten or go to another tilt screw. Make small adjustments and look at the effect on the star. Last night I had extremely flared stars and Jupiter's disk was blurry. I had relied on daytime collimation using the right tools are greatly worsened the situation. Within less than 5 minutes my flared stars assumed their round shapes with the dark spot of the secondary mirror centred in the bright outer ring of the out of focus star. After you have achieved collimation gently tighten the locking screws. My secondary mirror, luckily was not out of alignment. I would not want to be challenged with that problem. I am certain that the primary mirror of a Classical Cassegrain cannot be aligned unless performed on stars. The tools advertised by Starizona are too expensive and a waste of money$$.
I just got the 6" version of the TS Cassegrain. Can't wait for taking it out in the night sky :)
Excellent! I just got my TS-Optics 8" Richey-Chretien telescope. It looks very alike the classical Cassegrain. This is helpful info. Thank you very much. :)
Thanks! And have fun with the 8" RC
I have a 190mm f/12 GSO CC, It is an awesome planetary scope. I also have an Orion 180mm Maksutov. An equally impressive planetary scope.
We all appreciate the hard work you do in making these detailed which are extremely helpful in educating those of us who are new to the hobby... But could you please adjust your audio levels when dubbing in the music.... My neighbors are complaining...lol
I'm always struggling, thanks for the suggestion
@@AstroForumSpace And thank you again for all the hard work you do.. Your videos have helped me enormously in deciding which way I think I want to proceed and therefore what gear to spend my cash on..
@@pappy7510 hope you'll enjoy your astrogear. Clear skies!
I have a question, have you perhaps been able to find out how important the distance between the two mirrors is? When I bought my Omegon CR 153 used, the Jupiter satellites were perfectly round, but after cleaning the main mirror I had to replace everything adjust and since then the satellites have been more like triangles. I don't even know what to do anymore, I watched a lot of videos and found the right path for myself. I don't have an interface on the eyepiece that I could adjust the angle.
After making this particular video, I had the same issues and I returned the telescope. To properly collimate a classic RC, you'll need a specific laser collimator and there's a challenging collimation procedure. Astroaddict has a great video that explains how to do it: th-cam.com/video/TItMxGqwipk/w-d-xo.html I moved on to buying an Edge HD (modified SCT) which is much easier to collimate, but more expensive.
Hi Wido!! I am a devote fan of You channel and I have The sale tuve, but I cant find information about how clean the mirrows, do You have some links or data about it?
I Will really apreciate.
Regards from México!
Hi there, thanks! perhaps this helps: www.skyatnightmagazine.com/advice/how-to-clean-a-reflector/#:~:text=Fill%20the%20plastic%20bowl%20with,mirror%20surface%20at%20an%20angle.
I have the same telescope, gought at TS germany too, and collimation is very bad.
You're absolutely right when you say there are plenty of video or info, but non as clear as your.
Now I'm collimatin in the daylight, as soon as the fog is gone I would check on the stars as well.
Just one question regarding the star check, in the first case the oval star requires a little adjustment of the primary. But you do an out of focus as big as fo the test of the secondary?
Don't know if I'm clear
Hi Marco, I think in most cases, very minor adjustments of the secondary mirror should be enough. TS told me the primary is almost always correctly collimated. I became frustrated with this telescope and returned it to TS and replaced this one with a Celestron Edge HD. much easier to collimate, but more expensive.
Merci beaucoup
Hi... Thanks for the video. I am planning on getting a 8 inch classical Cassegrain myself. I would really appreciate if you can make a video of capturing a planet to show its capabilities . kind regards from India.
Make a video in .SER or .AVI format then process in Autostakkert! and the Registax.
@@dankahraman354 Thanks Dan! Should I use a 2x barlow or the native magnification is good enough?
The Barlow will give you a good magnification. Native may be a little on the small side, depending on your camera
@@AstroForumSpace Thanks a ton!
@@AstroForumSpace I used a 5x Barlow on the GSO f/12..I think it is the same Classical Cassegrain you have but different brand name, but the image quality deteriorated. Am I exceeding the magnification maximum at f/60? My camera has 6.9 micron pixels and 720x640 resolution.
Looks like a little bit more circumstantial than with a standard newton and a collimation laser.
But perhaps the correct collimation is kept for a while?!
I need to collimate really each time before usage and the laser always shows an essential decollimation...
And: even with laser collimation done, the "de-focused bright star"-check does not show a complete symmetrical picture (but photo looks ok; not like done with decollimation)...
Yes, to be completely honest, I love my refractor even more after using this scope :-).
thoko, after a proper collimation that will hardly need to be done for a long time. These scopes are built really heavy duty.
Super useful! Thank you.
You're welcome! How is that scope working for you?
@@AstroForumSpace Got clear sky yesterday after long and took it out for a proper observation session.. its a great step up from my 6 inch F5 newt.. though a bit on the heavier side for my CEM25p.. works great for planetary and visual. 😀
Very helpful as a guide to what's required. From what you are saying though it seems its not meeting your expectations in terms of pin sharp focus etc. I'm wondering if there's also an issue with the actual distance between the secondary and primary mirrors 'one to the other' - not just 'tilt' or rotational offset around and across the focal axis? In a few days (depending on the autumn weather we're now having to contend with (Western Europe) ... I'll be following along the same path :-) ) There seem to be other collation assistance devices - so not sure which is the best ... purely optical, or with an inbuilt laser? (In theory a Classical Cassegrain OTA should be 'easier' to collimate compared to an SCT, as there's no corrector lens in addition to the primary and secondary mirrors.)
Thanks for this video! Most channels suggest purchasing a Howie Glitter laser at approx $300 with the concentric holographic rings. I only paid $300 for the RC scope to begin with! Thanks for posting a more affordable approach! Can you achieve columnation with your Cheshire method that is close to the laser method?
Hi Robert, I would like to say yes, but unfortunately, that's not the case :-). Hope this helps, I did get a better view after this collimation procedure.
The Cheshire is a reliable and accurate method. The star test is the final conformation and if a good job was done it will be perfect.
I am clueless with my Meade et90, which is very old. I am looking to pay for collimattion in ny.
Hi there, I would check out if there are any astronomyshops nearby, they can probably help you out. Clear skies!
May I put two questions ?
1. How do you cope with your neighbours light pollution?. I suppose that when they see you out at night they will not go and switch of the lights....
2 when you are doing low angle shots, have you had complains from the same neighbours that you are piking on their houses? Just kidding
3 do you use light pollution filtering
4 why did you not bought a collimating kit?
What size are these wrenches?
Wow... get rid of those allen screws on the secondary! One little "Opps!" and the allen key is bouncing off of your primary mirror. Try www.bobsknobs.com/ I looked up your scope and it is not listed but if you call or email him I bet he will have something for you.
Bob's knobs are great but do require more frequent collimation.
The secondary on on a CC is not adjusted like a DOB the secondary is adjusted by using a Cheshire looking thru the back.So no danger of dropping on the primary mirror.
@@AstroForumSpace Why ? Once set they hardly ever need adjustment.
Yeah
Using a laser would be much easier just like a Newtonian telescope and more accurate than using your eye.
A update to my previous post. A Cheshire is the way to go. The alignment procedure is straight forward and takes just 10 minutes maybe more the first time. Just got mine and it is after all just a reflector. A Orion cc6.
I will now update my previous post. Align the primary as good as possible, after that use a laser just like you use on a DOB for the secondary and you are done. Takes a few minutes. It is very easy, DOB users do it all the time. Super easy . So now that you took it back you are missing out on the main benefits of a CC. You adjust the primary FIRST. The instructions that come with these telescopes are just a lot of nothing when it can be adjusted like a BOB. Remember it is just 2 mirrors no big deal.
@@ohwell2790 I do my collimation on my GSO 6" (the one shown here is the GSO 8") with a Baader laser collimator, held central in the focuser with an Orion centering 1.25" lens holder. Looking down the OTA from the front, I can just see the circle on the secondary. I then adjust using the rear allen key bolts of the primary mirror to get the laser in the centre of the circle. Then tighten up the primary mirror bolts. Next adjust the secondary mirror to shift the returning laser spot into the centre of the display plate on the laser itself. To doubly ensure the laser is seated properly, my RC OTO is face down on the HEQ5, so gravity is evenly seating the 1.25" holder and the Baader laser collimator. Does it work - yes it does. Takes about 5 - 10 minutes.
The cross hairs should be removed as they are of no use. As they are of no use collinating a refractor or a Cassingrain.