I am looking to pair an RC 6 with my CEM26 mount !! Total weight will be approx 9 kgs !! I am worried will it guide and balance properly !! Looking for suggestion and help !!
RC6 on a CEM26 Thoughts !!!!!!
I wouldn't do it.
Any specific reason @andrea tasselli
It isn't a really sturdy mount and it flexes a lot (I have its bigger brother and it is just the same), coupled with the focal length of your RC @ 9 kg (plus imaging gear I assume) and I don't think the combination is a winning one.
andrea tasselli:
It isn't a really sturdy mount and it flexes a lot (I have its bigger brother and it is just the same), coupled with the focal length of your RC @ 9 kg (plus imaging gear I assume) and I don't think the combination is a winning one.
*** including the imaging gear its about 9 kgs .. i used a 6”newt on it and had no issues i am see if any one has used this setup and looking to see some suggestions
I have successfully used my RC6 (now sold on) on a CEM25-EC. Care is needed with balancing but it tracked perfectly. Give it a go.
Payload capacity on it's own is not the most effective measuring stick for performance at longer focal lengths. Instead it comes down to the mechanical quality of the mount itself and therefore what average guide RMS error in arc seconds it is capable. As long as that average error is below your pixel scale than the mount should theoretically be able to handle it.
For example, if your pixel scale is 2.0 arc seconds/pixel but your scope is 30lbs then your mount will probably guide consistently below that.
But if your pixel scale is 0.5 arc seconds/pixel and your scope is 20 lbs, your mount will probably struggle.
For example, if your pixel scale is 2.0 arc seconds/pixel but your scope is 30lbs then your mount will probably guide consistently below that.
But if your pixel scale is 0.5 arc seconds/pixel and your scope is 20 lbs, your mount will probably struggle.
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andrea tasselli:
It isn't a really sturdy mount and it flexes a lot (I have its bigger brother and it is just the same), coupled with the focal length of your RC @ 9 kg (plus imaging gear I assume) and I don't think the combination is a winning one.
I have a CEM26 and use it with a 6 inch Newtonian and I do not have any flexing issues. That must’ve been issues with your specific unit. I regularly get tracking well underneath an arc second RMS even down to half an arc second RMS.
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Tarun Pulikanti:andrea tasselli:
It isn't a really sturdy mount and it flexes a lot (I have its bigger brother and it is just the same), coupled with the focal length of your RC @ 9 kg (plus imaging gear I assume) and I don't think the combination is a winning one.
*** including the imaging gear its about 9 kgs .. i used a 6”newt on it and had no issues i am see if any one has used this setup and looking to see some suggestions
This is what I have found. I use a 6 inch Newtonian on a CEM26. As long as you nail the balance, you’ll be fine. I regularly track it underneath an arc second RMS depending on my skies if I am in good skies in portal three I am consistently tracking it .5 to .6 RMS. So I’d say go for it and just make sure you nail balance.
Joseph Biscoe IV:
I have a CEM26 and use it with a 6 inch Newtonian and I do not have any flexing issues. That must’ve been issues with your specific unit. I regularly get tracking well underneath an arc second RMS even down to half an arc second RMS.
The mount itself does flex but this has little to do with tracking performance. It only go beserk when it flips sides at some pointing locations. I can get by with just jettisoning few frames but I'm running at 575mm focal length. Running at 1,200 mm is another matter entirely.
Hi,
If you already have a 6" Newt and the mount can take it, I think a 6" RC has the potential to be a little easier for the mount because it weighs about the same but is much shorter which means less torque. However, unlike all other designs that are more or less symmetric, RC and CC telescopes put almost their entire weight in the back (primary mirror + imaging gear). Not sure how this will play out. With a Newt you have about 30cm of cope protruding from each side, with the RC you could find your self in a situation where 45cm of scope protrudes from the front side to balance out what's in the back.
In any case, as Andrea pointed out, the RC has a much larger focal length. Which means it will "reveal" mount issues you are currently oblivious to, unless of course you bin or reduce to bring the FL closer to the Newt's.
Question is, why do all that? It seems like an awfully long detour to end up pretty much where you started. You are basically changing weight distribution and trading collimation frequency for collimation difficulty. But in the end, you will have the same type of scope (reflector with spikes, without CA, with significant stray light issues), the same weight and the same practically achievable resolution. Personally, I do not see the point. The only concrete reason for making the change is if you are aiming for specific targets that are framed better by a 1500mm-ish instrument with the camera binned at 2x2 instead of a 700mm-ish instrument with the camera at its native focal length. For example, consider how M63 is framed by a typical 6" Newt (yellow) vs a typical 6" RC (red). If you bin the RC, you end up sampling almost exactly like with the Newtonian, but sub size is 4 times smaller and you don't have to crop and throw away 3/4ths of the field (assuming of course you don't care about it). In my opinion, the benefit is marginal. You can simply use the ROI feature of your camera.
If you already have a 6" Newt and the mount can take it, I think a 6" RC has the potential to be a little easier for the mount because it weighs about the same but is much shorter which means less torque. However, unlike all other designs that are more or less symmetric, RC and CC telescopes put almost their entire weight in the back (primary mirror + imaging gear). Not sure how this will play out. With a Newt you have about 30cm of cope protruding from each side, with the RC you could find your self in a situation where 45cm of scope protrudes from the front side to balance out what's in the back.
In any case, as Andrea pointed out, the RC has a much larger focal length. Which means it will "reveal" mount issues you are currently oblivious to, unless of course you bin or reduce to bring the FL closer to the Newt's.
Question is, why do all that? It seems like an awfully long detour to end up pretty much where you started. You are basically changing weight distribution and trading collimation frequency for collimation difficulty. But in the end, you will have the same type of scope (reflector with spikes, without CA, with significant stray light issues), the same weight and the same practically achievable resolution. Personally, I do not see the point. The only concrete reason for making the change is if you are aiming for specific targets that are framed better by a 1500mm-ish instrument with the camera binned at 2x2 instead of a 700mm-ish instrument with the camera at its native focal length. For example, consider how M63 is framed by a typical 6" Newt (yellow) vs a typical 6" RC (red). If you bin the RC, you end up sampling almost exactly like with the Newtonian, but sub size is 4 times smaller and you don't have to crop and throw away 3/4ths of the field (assuming of course you don't care about it). In my opinion, the benefit is marginal. You can simply use the ROI feature of your camera.
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andrea tasselli:Joseph Biscoe IV:
I have a CEM26 and use it with a 6 inch Newtonian and I do not have any flexing issues. That must’ve been issues with your specific unit. I regularly get tracking well underneath an arc second RMS even down to half an arc second RMS.
The mount itself does flex but this has little to do with tracking performance. It only go beserk when it flips sides at some pointing locations. I can get by with just jettisoning few frames but I'm running at 575mm focal length. Running at 1,200 mm is another matter entirely.
It's interesting your mount is flexing. Im shooting at 750mm at 1.03" and usually wind is my biggest issue.
Why not try it but use a reducer to bring down the focal length???. A 0.73x will bring it down to around 950 mm….
Just a thought.
Just a thought.
SO finally I got the RC6 and Tested it with it on the CEM 26 and it worked flawlessly on first light testing !! the balance was good and was able to guide at .5"-.7" with rough PA. CEM26 is a very capable mount in this regards !!
my first light !! 30 sec x 20 subs
I use a CEM25 + SV550 122mm triplet. It includes 50mm guider, dew heaters, camera, filter drawer etc
I used it with IMX585 which gave me 0.7"/pixel
I spend a long time balancing and polar aligning then calibrating etc to get the most of it and still it will give me 60s max, maybe 90s subs
I would have to throw out a lot of subs
With the RC6 it should work but it might struggle a bit. Should be fine for brighter targets tho
I used it with IMX585 which gave me 0.7"/pixel
I spend a long time balancing and polar aligning then calibrating etc to get the most of it and still it will give me 60s max, maybe 90s subs
I would have to throw out a lot of subs
With the RC6 it should work but it might struggle a bit. Should be fine for brighter targets tho
Tarun Pulikanti:
my first light !! 30 sec x 20 subs
Neat!
I run it with a 6” RC for five minutes and it is fine. As others have said you have to be meticulous with polar alignment and balance.
Tarun Pulikanti:
my first light !! 30 sec x 20 subs
Hi, Are you still using the RC6 with CEM 26? How is it working for you?
I"m thinking about doing the same. My imaging load will be less than 9KG, just under 7.
I use the CEM26 with the GSO RC6 with no problems. I even use a heavier refractor on it and it works fine. You must be very precise with level, polar alignment and balance to get it working properly.