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CEM40EC & iPolar review

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340 replies to this topic

#326 mewmartigan

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Posted 05 September 2019 - 03:18 PM

Thanks, I will try the hex wrench for tightening. Glad I just recently sold off my two ADM losmandy style plates. My z103 came with a vixen and it just never occurred to me to switch. Grrrrrr

#327 Masher

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Posted 05 September 2019 - 07:13 PM

Chuck, I had the same. Although it should not affect your tracking, I just re-centered the counterweight shaft.
You have three allen bolts (one silver and two black) on the shaft head (the one that surrounds the ipolar) that are locking the shaft in position, just jently loose them and slightly push the head left or right to find a good alignment

Hi Nik:

 

I tried this but it didn't work. The larger silver hex screw actually threads into the RA shaft and fixes the position once tightened. It's been five days since I emailed iOptron support on a couple questions without a response, so looks like I'm on my own. The balance issue I'm having is minor so I'm anticipating it won't affect guiding as you mentioned. Clear skies and thanks again for your help.

 

---- Chuck



#328 niccoc1603

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Posted 06 September 2019 - 12:07 AM

Yes, but it has a small.play, that was enough for me to adjust the shaft. If you need a larger rotation of the head (I doubt) you can just tighten the two black bolts and not use the silver one, it will be solid enough

But as you say it will probably be fine even with a small unbalance. I haven't noticed any significant improvement in tracking and guiding performance since I adjusted the shaft.

#329 Masher

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Posted 06 September 2019 - 08:25 AM

Yes, but it has a small.play, that was enough for me to adjust the shaft. If you need a larger rotation of the head (I doubt) you can just tighten the two black bolts and not use the silver one, it will be solid enough

But as you say it will probably be fine even with a small unbalance. I haven't noticed any significant improvement in tracking and guiding performance since I adjusted the shaft.

@ Nik: Yes, I did notice a very small amount of play, but no where near enough to correct the misalignment I have. I'm not comfortable going with just the two small hex bolts, especially if I ever need to use three CW's, as those are just contacting the RA shaft and not threaded into it. I may just do a bench test, using just the two small hex screws to correct the offset I have, to see if it actually solves the balance issue using a small payload and one CW. More to follow later.

 

@ OP: Sorry to have highjacked this thread a bit. Thanks for your understanding.

 

 

---- Chuck



#330 mewmartigan

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Posted 06 September 2019 - 09:59 AM

Thanks, I will try the hex wrench for tightening. Glad I just recently sold off my two ADM losmandy style plates. My z103 came with a vixen and it just never occurred to me to switch. Grrrrrr

Last night I hand tightened the clamps down as best I could. Using a hex wrench then, I was able to get probably another complete rotation and half. So I guess the hex wrench is now part of the kit.



#331 cfichter

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Posted 09 September 2019 - 08:15 PM

After initial, short-lasting problems with guiding that was resolved by calibration and installing a newer mount firmware update 20190621 (thanks to one of this forum's posters), I am regularly using my CEM40EC for more than a month.

 

Depending on the seeing conditions, the usual RMS is less than 0.5 arcsec. 

 

I am satisfied by other aspects of this mount more than I have expected, too. Controlling by ASIAIR, it is very easy to setup and start the imaging.

 

This is my first fully processed astro image obtained using this mount: https://www.astrobin...420394/?nc=user

 

Sasho

 

That's a great result there, Sasho - impressive guiding, nice looking stars at that fl - good job. This mount (ec version) is pretty exciting imho from what I'm seeing in the thread, even up to a 130mm scope.  What is your total payload on this Sasho?  I'm going to guess around 10-12kg?



#332 cfichter

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Posted 09 September 2019 - 08:18 PM

I am also reporting good performance from my CEM40 (non EC)

 

Last night guiding over 3hrs was excellent, with minimal backlash (150-250ms)

This probably is good? Wish folks would post their payload and image scale when they give these stats- hard to ascertain with just these numbers real perf -



#333 niccoc1603

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Posted 09 September 2019 - 11:40 PM

This is a >300 posts thread, folks should read it from the beginning and they would find all the answers to their questions

Edited by niccoc1603, 09 September 2019 - 11:45 PM.

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#334 Sasho_Panov

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Posted 10 September 2019 - 05:07 AM

That's a great result there, Sasho - impressive guiding, nice looking stars at that fl - good job. This mount (ec version) is pretty exciting imho from what I'm seeing in the thread, even up to a 130mm scope.  What is your total payload on this Sasho?  I'm going to guess around 10-12kg?

Thanks cfichter,

 

The total payloda (scope + imaging train) is 8.2 kg (18 pounds).

 

Sasho



#335 txo

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Posted 18 September 2019 - 05:08 PM

Hi guys. This is my final verdict on the mount. 

 

I really struggled with it but now when I solved all the quality control issues, got refractor telescope that doesn't have much of a asymmetrical weight distribution and learned how to deal with EC mount the result is in the picture attached.

 

I must say, that I have maxed out my payload to 15kg now!

 

cheers smile.gif

 

cem40EC 15kg payload

Edited by txo, 18 September 2019 - 05:19 PM.

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#336 niccoc1603

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Posted 18 September 2019 - 08:23 PM

+1 for NINA

#337 Piggled

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Posted 30 September 2019 - 06:01 PM

Ok. Well. The first few pages of this thread are great, a lot of info. Didn’t have time to go through it all. I just ordered this mount. I have an infant and a small woodworking business. I don’t have time to deal with this crazy stuff. Should I send this mount back? I have a takfsq85 and an asi1600mm haven’t purchased the guide scope because I haven’t heard from ioptron and I’m not sure which to pick up that won’t screw with the focuser(oag). Let me know. I do DIY all day long. Don’t want to do more when I get home.......

#338 tbcgeorge

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Posted 30 September 2019 - 07:46 PM

Ok. Well. The first few pages of this thread are great, a lot of info. Didn’t have time to go through it all. I just ordered this mount. I have an infant and a small woodworking business. I don’t have time to deal with this crazy stuff. Should I send this mount back? I have a takfsq85 and an asi1600mm haven’t purchased the guide scope because I haven’t heard from ioptron and I’m not sure which to pick up that won’t screw with the focuser(oag). Let me know. I do DIY all day long. Don’t want to do more when I get home.....

 

Hi there! I would say no worries, most of the problem is actually raised by heavy payload, your FSQ85 should be just a bit heavier than my GT81, so encoder should be working out of the box, no need to worry about firmware updates. When you get it, balance the OTA well, do a proper polar alignment with iPolar, then point the scope to anywhere around celestial equator, take 3 subs of 1sec, 10 sec, 30 sec, 60 sec and 120sec each. I would expect you have round stars at least with 60 sec exposures. (I assume you're talking about the EC version here, if not, you should be at least good with 10 sec subs.)


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#339 Piggled

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Posted 01 October 2019 - 02:53 PM

Hi there! I would say no worries, most of the problem is actually raised by heavy payload, your FSQ85 should be just a bit heavier than my GT81, so encoder should be working out of the box, no need to worry about firmware updates. When you get it, balance the OTA well, do a proper polar alignment with iPolar, then point the scope to anywhere around celestial equator, take 3 subs of 1sec, 10 sec, 30 sec, 60 sec and 120sec each. I would expect you have round stars at least with 60 sec exposures. (I assume you're talking about the EC version here, if not, you should be at least good with 10 sec subs.)


Awesome. I do plan on guiding as I would like to do longer than 2 minute exposures in narrowband. But I spoke with Dustin at OPT and he assured me it’s an excellent mount and if there are issues to just send it back.

#340 Merc

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Posted 01 October 2019 - 04:56 PM

Hi there! I would say no worries, most of the problem is actually raised by heavy payload, your FSQ85 should be just a bit heavier than my GT81, so encoder should be working out of the box, no need to worry about firmware updates. When you get it, balance the OTA well, do a proper polar alignment with iPolar, then point the scope to anywhere around celestial equator, take 3 subs of 1sec, 10 sec, 30 sec, 60 sec and 120sec each. I would expect you have round stars at least with 60 sec exposures. (I assume you're talking about the EC version here, if not, you should be at least good with 10 sec subs.)

Hi, Ben

 

Appreciate your relevant videos, btw.

 

Hey, just to be clear on your recommendation....you say the 'problem' is driven by a heavy payload. Not sure how you're defining 'heavy', if you can share that information....like up to 80% of recommended payload capacity, for example?

 

Also, I thought there were some owners that had issues with focal length [like over 900mm], as well...although, that tends to go hand-in-hand. Can you comment on that?

 

That is an issue with the CEM60EC, so that's one reason I ask.

 

Let me [us] know, please if you have any info to share on that.

 

Best,

 

Merc



#341 tbcgeorge

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Posted 03 October 2019 - 09:58 AM

Hi Merc,

 

Sorry for the late reply, I was working on another Youtube video about E180...

 

As much as I hate the "50% rule" on mount payload, I will still quote that for my definition of "heavy payload". 50% of 40lb is 20lb, so if your total payload on this mount is less than 20lb, I consider it not heavy, and there should be no issue. Did I test it? NO... I only tested it with my GT81 (that's the only other OTA I have btw), and the unguided result was great (I have a Youtube video on that). That's why I told Piggled he should be fine with his FSQ85, being almost same weight and focal length as my GT81.

 

Longer focal length I'm really not sure. I know I always use 200%-300% magnification to exam my subs (with E180, fl=500mm, 32lb payload), the stars are round there. But that might be different from taking subs with 2x focal length and viewing them on 100%...

 

Still, in my opinion, this mount should work well for 900mm, which is a mainstream focal length for telescopes.

 

Hi, Ben

 

Appreciate your relevant videos, btw.

 

Hey, just to be clear on your recommendation....you say the 'problem' is driven by a heavy payload. Not sure how you're defining 'heavy', if you can share that information....like up to 80% of recommended payload capacity, for example?

 

Also, I thought there were some owners that had issues with focal length [like over 900mm], as well...although, that tends to go hand-in-hand. Can you comment on that?

 

That is an issue with the CEM60EC, so that's one reason I ask.

 

Let me [us] know, please if you have any info to share on that.

 

Best,

 

Merc




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