20 replies to this topic

[Sean13]

I have recently picked up the Apetura 6" RC scope for my larger sensor, longer focal length imaging scope hopefully. I enjoy the C6, but the baffle tube is just too small to fit any descent sized camera and OAG on reliably enough to be a full remote imaging setup for me. I hope this RC can cure that issue.

 

I see many images with this scope and people using the asi2600 (no duo) with great results. I have measured the baffle tube and it appears to be ~41mm-42mm in size at its smallest point. This is roughly 5"-6" away from the camera sensor, or more, and I understand that baffle tube size does not equal image circle size. The 2600 Duo advises an image circle of 44mm minimum to use the setup. I know I can cut it closer with a conventional OAG setup, but I'd like the simplicity and reliability of the Duo setup as this is expected to be a full hands off remote imaging setup when complete. Does anyone have any advice on if I risk it for the biscuit? 

 

I know not many people are running this scope to start with, and I can find no one posting on Astrobin with this scope and the 2600 Duo yet (Unless they are just mislabeling it as a standard 2600 maybe?) I'm sure alot more are running the 8" Apetura and GSO versions, do you guys have any image circle issues with full frame cameras? I would assume if you can run full frame with no issues, I could run the Duo which should need around the same image circle. 

Edited by Sean13, 17 February 2025 - 12:34 PM.

[Whendewsday]

Personally, I'd risk it. Seems like you may still catch plenty of guide stars, but I am still a newbie. I do have this scope and a standard 2600MC Pro, so I am curious what you end up doing anyway. I only got a few good nights out of that focuser before it started to slip too (with EFW, OAG). I just purchased the TS R&P focuser to fix that part of the setup.

[larrymax]

I just received an Apetura RC6 CarbonStar. Not sure if the baffle is the same, but I have a full frame Canon 6D I could test it on...

[pdfermat]

I just received an Apetura RC6 CarbonStar. Not sure if the baffle is the same, but I have a full frame Canon 6D I could test it on...

That would be great if you have the time!!  I'm very curious about this myself.

[larrymax]

I'll need a bit. Going back to work tomorrow after 2 weeks off. Just got it today and I haven't opened it  

 

I guess I'll mount it and put my light panel for flats on? Would that work...? Outside is a no go for a while. Clouds as usual.

 

Still waiting on the reducer to show up.

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[Ranger Tim]

Yes, the duo will work with a 6 inch RC. Here’s proof. The guide stars will be a bit wonky and the RC needs a field flattener though.

 

[Sean13]

I'll need a bit. Going back to work tomorrow after 2 weeks off. Just got it today and I haven't opened it

 

I guess I'll mount it and put my light panel for flats on? Would that work...? Outside is a no go for a while. Clouds as usual.

 

Still waiting on the reducer to show up.

No worries, I'm still curious to see the flats even tho it looks like it's not likely going to work to the degree I'm looking for. If you have the flattener, it would be interesting to see both with and without it. I did not buy the flattener as I intended to use it at native FL.

 

 

Yes, the duo will work with a 6 inch RC. Here’s proof. The guide stars will be a bit wonky and the RC needs a field flattener though.

 

Welp, thats depressing but thanks for the info. I an not using a field flattener as its also a reducer and my only point of this scope is its ~1450mm FL. I also can't deal with wonky guide stars and the risk of there ever being an issue as I need this to be full remote capable. Looks like I'll be better served with a conventional OAG or guide scope setup. Thanks a ton for the info tho!

[pdfermat]

No worries, I'm still curious to see the flats even tho it looks like it's not likely going to work to the degree I'm looking for. If you have the flattener, it would be interesting to see both with and without it. I did not buy the flattener as I intended to use it at native FL.

 

 

Welp, thats depressing but thanks for the info. I an not using a field flattener as its also a reducer and my only point of this scope is its ~1450mm FL. I also can't deal with wonky guide stars and the risk of there ever being an issue as I need this to be full remote capable. Looks like I'll be better served with a conventional OAG or guide scope setup. Thanks a ton for the info tho!

I'm in a similar boat as you.  I'm planning on building a rig with the Apertura RC6, and I would be using it to image small-ish galaxies at its native focal length (almost exclusively).  I'd like the 2600 duo to work for a number of reasons, but it looks more and more like a 533 with the ZWO OAG-l and a 174 mini guide cam will be a better fit.

[Ranger Tim]

I use a 1X flattener yielding the native 1380mm focal length on my AT6RC. The wonky stars I describe can still result in good guide numbers. A 6 inch RC is a bag of compromises to meet the price point. If you spend the time to tune its optics and have patience it can give you really good pics. They are not ready out of the box IMO. Mine uses the AT2FF flattener, a replacement focuser, a focuser decoupling ring, and a baffle tube extension - these add-ons cost more than I paid for the scope! And I still fuss with collimation periodically. Many people give up with these scopes. I was an early adopter and can get mad at it, but can usually make it perform. Eventually I will replace it with a long triplet refractor, but someone has to die and leave me money first.

[Sean13]

I'm in a similar boat as you.  I'm planning on building a rig with the Apertura RC6, and I would be using it to image small-ish galaxies at its native focal length (almost exclusively).  I'd like the 2600 duo to work for a number of reasons, but it looks more and more like a 533 with the ZWO OAG-l and a 174 mini guide cam will be a better fit.

The 2600 standard looks great with it, and I have a feeling with the OAG you can squeeze the pickoff closer to the image field without effecting the main camera and possibly need less space then the Duo does. The main reason I didn't like the C6 was that I had to stick with a 533 camera and FR to even consider fitting an OAG on there. Its baffle was something like 22mm or something. This one has almost 42mm, so I bet you can do better then a 533. I may just put a guide scope on it with the 2600 if I have to.

 

I use a 1X flattener yielding the native 1380mm focal length on my AT6RC. The wonky stars I describe can still result in good guide numbers. A 6 inch RC is a bag of compromises to meet the price point. If you spend the time to tune its optics and have patience it can give you really good pics. They are not ready out of the box IMO. Mine uses the AT2FF flattener, a replacement focuser, a focuser decoupling ring, and a baffle tube extension - these add-ons cost more than I paid for the scope! And I still fuss with collimation periodically. Many people give up with these scopes. I was an early adopter and can get mad at it, but can usually make it perform. Eventually I will replace it with a long triplet refractor, but someone has to die and leave me money first.

Thats the exact reason I purchased the 6" RC instead of investing more into the C6 because it would cost the same to make the C6 what I consider remote-ready then the RC costs in the first place. I got it because it had a large baffle tube, and supposedly well corrected enough to not need a flattener. I assumed the focuser would be suitable for a basic cooled color camera setup, but it isn't. I already can't figure out my collimation issue due to never collimating an RC before. Thru a cap everything looks collimated correctly, but my stars look horrible, so clearly something is off. Weather is just too cold right now to want to site outside and tinker with it, so hopefully its up and working good by summer at least .

[Ranger Tim]

Sitting in the cold collimating is no bueno!

[TerryD1]

I'll need a bit. Going back to work tomorrow after 2 weeks off. Just got it today and I haven't opened it

 

I guess I'll mount it and put my light panel for flats on? Would that work...? Outside is a no go for a while. Clouds as usual.

 

Still waiting on the reducer to show up.

What reducer did you order?  If it's the one that's sold for the GSO RC6 and 8s I'd send it back, because the image circle it produces is small and may not work with the DUO.  A lot of us RC guys use the CCD Telecompressor (CCDT67) from Astro-Physics.  It's a good price from a company like Astro-Physics and will produce an image circle that works with the DUO.  I know because I have the DUO and this compressor that I use on an RC8.

[Sean13]

What reducer did you order?  If it's the one that's sold for the GSO RC6 and 8s I'd send it back, because the image circle it produces is small and may not work with the DUO.  A lot of us RC guys use the CCD Telecompressor (CCDT67) from Astro-Physics.  It's a good price from a company like Astro-Physics and will produce an image circle that works with the DUO.  I know because I have the DUO and this compressor that I use on an RC8.

Interesting. The specs for that FR state a much smaller image circle, but I see that many are using it with the GSO scopes. I was not aware of this one until now. However it doesn't solve my particular issue as I don't want any focal reduction for my application.

 

Its becoming more and more evident to me that to accomplish my particular goal I am going to likely need a larger scope and use a focal reducer to get back to that ~1500mm FL that I'm looking for. I likely made a mistake in thinking this 6" RC could do things the C6 could not, and should have been focusing on a larger OTA instead of trying to scrape by with the smallest OTA possible.

[pdfermat]

Interesting. The specs for that FR state a much smaller image circle, but I see that many are using it with the GSO scopes. I was not aware of this one until now. However it doesn't solve my particular issue as I don't want any focal reduction for my application.

 

Its becoming more and more evident to me that to accomplish my particular goal I am going to likely need a larger scope and use a focal reducer to get back to that ~1500mm FL that I'm looking for. I likely made a mistake in thinking this 6" RC could do things the C6 could not, and should have been focusing on a larger OTA instead of trying to scrape by with the smallest OTA possible.

I’ve been debating along the same lines, 2 other options I’ve been considering:

 

Edge HD 8” with reducer - but significantly more $$, still would want to upgrade the focuser so I could use the mirror locks, and would have to deal with significantly more dew.

 

8” RC with focal reducer - basically a faster system with about the FL I’m looking for - a little more $$.

[Sean13]

I’ve been debating along the same lines, 2 other options I’ve been considering:

 

Edge HD 8” with reducer - but significantly more $$, still would want to upgrade the focuser so I could use the mirror locks, and would have to deal with significantly more dew.

 

8” RC with focal reducer - basically a faster system with about the FL I’m looking for - a little more $$.

I think I'm going to give this little scope a chance with a separate guide scope and see how it goes. I suspect I will be ok below 1500mm with a descent guider setup that its worth a shot. I think with a 40+mm baffle that I'll be ok using the 2600 with no flattener or reducer, but I guess we'll see. If it doesn't work out, I'll keep the camera and sell the scope I guess.

[larrymax]

What reducer did you order?  If it's the one that's sold for the GSO RC6 and 8s I'd send it back, because the image circle it produces is small and may not work with the DUO.  A lot of us RC guys use the CCD Telecompressor (CCDT67) from Astro-Physics.  It's a good price from a company like Astro-Physics and will produce an image circle that works with the DUO.  I know because I have the DUO and this compressor that I use on an RC8.

Apertura .67 The OP wanted to see what a full frame camera would look like with the OTA. Just trying to help out. I should have some time Tuesday. I won't be using the focal reducer. Going to set it up inside and use my light panel for flats with the 6D. Hopefully this helps them. 

 

I don't own a OAG. I'm perfectly happy with a seperate scope and camera for now. I'm still so new to this, but I'm sure one day I'll go for an OAG. I've had great results with a ASI224MC and a ZWO 30mm.

 

I will also be using an ASI533 with the RC6. I should be good with the focal reducer.

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Edited by larrymax, 23 February 2025 - 04:44 PM.

[larrymax]

Had some time today and took it out of the box. Getting prepped for the test

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Edited by larrymax, 24 February 2025 - 09:19 PM.

[larrymax]

 With or without the reducer, I didn't see anything in the way of the sensor on the 6D. Zero "roundness"  I think you're good. 

Edited by larrymax, 25 February 2025 - 11:36 PM.

[Sean13]

 With or without the reducer, I didn't see anything in the way of the sensor on the 6D. Zero "roundness"  I think you're good. 

That is interesting. Perhaps this isn't exactly the same as the clones it was built from then. Maybe it is worth trying.

[larrymax]

That is interesting. Perhaps this isn't exactly the same as the clones it was built from then. Maybe it is worth trying.

My first attempt wasn't the best. I spent some time getting it ready for first light tonight and learning. I'll do it all again hopefully early next week. Nevermind the 533, I was doing adaptor roulette just to see how things fit after I stole it all off the RedCat.

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[mayhem13]

 

Its becoming more and more evident to me that to accomplish my particular goal I am going to likely need a larger scope and use a focal reducer to get back to that ~1500mm FL that I'm looking for. I likely made a mistake in thinking this 6" RC could do things the C6 could not, and should have been focusing on a larger OTA instead of trying to scrape by with the smallest OTA possible.

I’ve found that the most effective, smallest and lightest option for 1500mm FL is a Celestron C9.25 with the Starizona SCT .63 reducer which results in an evenly lit and well corrected 18mm imaging circle if you take the time to dial in the optimal backfocus.

 

Now your CGXL ‘could’ certainly handle the larger option for 1500mm which would be a 12” F5 Newtonian……but a scope like that is going to require a lot of mods and tweaks or dare even a custom build to be viable for AP.