Very cool thanks for this. Understanding the 3rd axis is not easy, and no mount companies even address this issue. I have an iOptron cem26 and a Skywatcher star adventurer 2i Ill be utilizing this on. Cheers!
Have a CEM40 as well. I also have this in-balance as you can see in some of my video's. I didn't experience many issues do to the imbalance though. Usually I am around 0.60 RMS with my EdgeHD 8" telescope on it. Knew about this possible solution before but never thought of trying it. Perhaps I'll do after seeing your vid. Might get the RMS even lower.
Thank you for posting this video and the links - especially the clamp! I was finally able to balance my CEM70 (after two years) and the guiding improved dramatically. I tried some of the suggestions on the iOptron Groups (loosen screws to move the Ra "collar", or apply a shim) and none of those worked. This did!
Had a similar issue with my EQ6-R and used a 2 oz magnet on the counterweights to achieve balance. I have a 8" RASA w/ZWO EAF and ZWO 30mm guide scope. The EAF does cause an offset and the guide scope sits opposite to it on the OTA and reduces that difference in 'pitch'. I've since made adjustments to the center of balance on the OTA and find that the closer you get to center balance on the OTA the weight offset can be zeroed out. And I thought it was just me that had the problem.... nope. Thanks for the re-assuring video :)
Thanks for this info! Quick question, though. If this helped you balance to the point where you were tracking unguided and had eliminated star drift - WHY did you start using guiding software AND spend money on a guiding cam / mini scope???? So, you continued to have tracking issues in spite of the encoder??? Hope you reply, Al
Hi Al, so proper balance is essential for any long exposure and for the mount to operate well without putting undue strain on it. But if you want to do 4, 5 minute or longer exposures, you need to guide. Guiding also enables you to dither which helps reduce overall noise. No issues with this mount but as in my other video's, my CEM26EC mount needed repairs before it operated properly unguided.
The Cem60 21# counter weight has 2 threaded holes on the sides for exactly this purpose, inserting a threaded rod for additional axis counter balancing. I believe the holes are M8. I don't know about their other weights, if they have the same holes or not. I also believe there is an actual kit you can purchase that includes all the necessary items. So in essence, if your counter weight has these holes, all you need is the rod, a couple nuts and some fender washers.
I solved the problem on my CEM40EC by using proportionate weights on the shaft. The upper shaft weight is a 2.5K weight and the lower shaft weight is 5.0K. By shifting the proportion of weight on the shaft, I can balance the mount so that it is "Slightly" east heavy and prevent backlash.
As you mentioned, others have had similar issues with the CEM mounts. In theory these new center balanced mount designs make a lot of engineering sense but anecdotal evidence suggests that there are some issues to be ironed out. These same problems have not been reported to the same extent for the GEM series, a much older and slightly 'outdated' design. On the other hand, the GEM carries more physical weight than the CEM (about 5 lbs) without itself weighing more than the CEM, again suggesting that the CEM design is innovative but not yet superior to the old GEM designs. The differences are ultimately minor, i.e. both mounts perform great and any limitations are those of the operator.
I’m confused. Once you change the declination of the mount, won’t you have to again adjust the orientation of the z axis weight? Since on the ioptron mount the counterweight shaft doesn’t rotate with the Declination as it does on normal eq mounts?
I have the same issue on my CGEM on the DEC axis, but not the RA axis. ADM just came out with the DVCW-SM D and V Series Counterweight to address this issue.
Hey Dave....cool hack. I know you’ve had a lot of frustrations with that mouth so far but now that you’re getting everything ironed out I bet you’re gonna have a blast. Can’t wait to see what kind of images you’ll be able to take with that mount and the beast of a scope you got on there.
Hi, thanks for the helpful video! :) And if I may ask.. How many kilos is your setup? I'll be trying this on a cem70 and I have a 10" Newtonian, which with all of the gear weighs about 16-17 kilos.
This video "iOptron Cem70 RA Balance fix no washers, rods needed" says you don't need the washers! Have you tried this yet? I always enjoy your videos. Thanks
Your counterweight bar it’s not perfect center , if you loosen the 3 screws close to the pole scope and give a small push to left or right will fix this problem, you don’t need any side counterweight
ThaT would have been great but unfortunately on my CEM40 i was only able to move the shaft to the right and not to the left. This means that you can only do it by drilling a hole in the mount!
I’m a beginner with a new eq6-r pro and was just out shooting elephants trunk and my scope was past the zenith and my images were perfect at 120sec and guiding at 0.6 rms maximum. A guy messaged me and he’s been doing it for years and when he heard how well my mount was doing he couldn’t believe it lol
Yea, CEM mounts have this issue. My CEM70G does the same, but my GEM45 of course does not. The CEM70 has allen screws around the RA counter weight attachment section that allows a left-right shift so that the counterweight bar is properly aligned with the DEC axis and the one sided RA weight problem is fixed. Have a look at this which I found on the CEM70, just in case you mount has the same option...n ruclips.net/video/AnE5ikgzX7s/видео.html
@@Backnine59 You need unlock screws on CW shaft and move it. You will eventually find balance. There are RUclips videos that show it. If you ask me. The best is to rid off any IOptron mount. Done it, and very happy.
![FNAF vs TF2 - Episode 2 [SFM]](http://i.ytimg.com/vi/z5b3V2-VLb0/mqdefault.jpg)
Very cool thanks for this. Understanding the 3rd axis is not easy, and no mount companies even address this issue. I have an iOptron cem26 and a Skywatcher star adventurer 2i Ill be utilizing this on. Cheers!
Have a CEM40 as well. I also have this in-balance as you can see in some of my video's. I didn't experience many issues do to the imbalance though. Usually I am around 0.60 RMS with my EdgeHD 8" telescope on it.
Knew about this possible solution before but never thought of trying it. Perhaps I'll do after seeing your vid. Might get the RMS even lower.
I just used this method on my CEM26 and guiding improved dramatically - especially near the NCP. Thanks for the tip!
That's great, thanks so much!
Brilliant! I have exactly the same issue to fix on my Avalon Linear mount. This will work a treat. Thank you for a great solution 👍
I was aware about 3 D balancing I was using my locking pliers. this looks great. thanks for the tutorial.
Thank you for posting this video and the links - especially the clamp! I was finally able to balance my CEM70 (after two years) and the guiding improved dramatically. I tried some of the suggestions on the iOptron Groups (loosen screws to move the Ra "collar", or apply a shim) and none of those worked. This did!
Awesome! Glad it worked!
Had a similar issue with my EQ6-R and used a 2 oz magnet on the counterweights to achieve balance. I have a 8" RASA w/ZWO EAF and ZWO 30mm guide scope. The EAF does cause an offset and the guide scope sits opposite to it on the OTA and reduces that difference in 'pitch'. I've since made adjustments to the center of balance on the OTA and find that the closer you get to center balance on the OTA the weight offset can be zeroed out. And I thought it was just me that had the problem.... nope. Thanks for the re-assuring video :)
Thanks for sharing that! I quickly found out what a difference proper balance really makes 👌
@@keystothecosmos7527 Yup, makes PHD2 look near perfect.
Thanks for this info!
Quick question, though.
If this helped you balance to the point where you were tracking unguided and had eliminated star drift
- WHY did you start using guiding software AND spend money on a guiding cam / mini scope????
So, you continued to have tracking issues in spite of the encoder???
Hope you reply,
Al
Hi Al, so proper balance is essential for any long exposure and for the mount to operate well without putting undue strain on it. But if you want to do 4, 5 minute or longer exposures, you need to guide. Guiding also enables you to dither which helps reduce overall noise. No issues with this mount but as in my other video's, my CEM26EC mount needed repairs before it operated properly unguided.
The Cem60 21# counter weight has 2 threaded holes on the sides for exactly this purpose, inserting a threaded rod for additional axis counter balancing. I believe the holes are M8. I don't know about their other weights, if they have the same holes or not. I also believe there is an actual kit you can purchase that includes all the necessary items. So in essence, if your counter weight has these holes, all you need is the rod, a couple nuts and some fender washers.
I've heard that before with the bigger mounts but unfortunately my counterweights don't have those holes
I solved the problem on my CEM40EC by using proportionate weights on the shaft. The upper shaft weight is a 2.5K weight and the lower shaft weight is 5.0K. By shifting the proportion of weight on the shaft, I can balance the mount so that it is "Slightly" east heavy and prevent backlash.
As you mentioned, others have had similar issues with the CEM mounts. In theory these new center balanced mount designs make a lot of engineering sense but anecdotal evidence suggests that there are some issues to be ironed out. These same problems have not been reported to the same extent for the GEM series, a much older and slightly 'outdated' design. On the other hand, the GEM carries more physical weight than the CEM (about 5 lbs) without itself weighing more than the CEM, again suggesting that the CEM design is innovative but not yet superior to the old GEM designs. The differences are ultimately minor, i.e. both mounts perform great and any limitations are those of the operator.
Very interesting. Thanks for your input
I’m confused. Once you change the declination of the mount, won’t you have to again adjust the orientation of the z axis weight? Since on the ioptron mount the counterweight shaft doesn’t rotate with the Declination as it does on normal eq mounts?
Not sure I know what you mean but the counterweight shaft rotates with the RA like most mounts, not the declination.
Clever solution! Thanks for sharing.
I have the same issue on my CGEM on the DEC axis, but not the RA axis. ADM just came out with the DVCW-SM D and V Series Counterweight to address this issue.
Hey Dave....cool hack. I know you’ve had a lot of frustrations with that mouth so far but now that you’re getting everything ironed out I bet you’re gonna have a blast. Can’t wait to see what kind of images you’ll be able to take with that mount and the beast of a scope you got on there.
Thanks Everett!
Hi, thanks for the helpful video! :)
And if I may ask.. How many kilos is your setup?
I'll be trying this on a cem70 and I have a 10" Newtonian, which with all of the gear weighs about 16-17 kilos.
Thank you. I'd say with my ED 127 scope, I'm somewhere around 10-11 kilos
Curious on the camera clamp model : Amazon has it?
Yes that's correct. I purchased it from Amazon
This video "iOptron Cem70 RA Balance fix no washers, rods needed" says you don't need the washers! Have you tried this yet? I always enjoy your videos. Thanks
Thanks! Interesting, no I haven't. I'll have to check that out!
I just tried that with my cem70 and it only fixed the issue in one direction.
Your counterweight bar it’s not perfect center , if you loosen the 3 screws close to the pole scope and give a small push to left or right will fix this problem, you don’t need any side counterweight
ThaT would have been great but unfortunately on my CEM40 i was only able to move the shaft to the right and not to the left. This means that you can only do it by drilling a hole in the mount!
I’m a beginner with a new eq6-r pro and was just out shooting elephants trunk and my scope was past the zenith and my images were perfect at 120sec and guiding at 0.6 rms maximum. A guy messaged me and he’s been doing it for years and when he heard how well my mount was doing he couldn’t believe it lol
Yea, CEM mounts have this issue. My CEM70G does the same, but my GEM45 of course does not. The CEM70 has allen screws around the RA counter weight attachment section that allows a left-right shift so that the counterweight bar is properly aligned with the DEC axis and the one sided RA weight problem is fixed. Have a look at this which I found on the CEM70, just in case you mount has the same option...n
ruclips.net/video/AnE5ikgzX7s/видео.html
Wow
There’s better approach. This is very primitive approach.
So what is the better approach?
@@Backnine59 You need unlock screws on CW shaft and move it. You will eventually find balance. There are RUclips videos that show it.
If you ask me. The best is to rid off any IOptron mount. Done it, and very happy.