Ioptron CEM25 coming

[kalasinman]

I heard today from Ioptron that as soon as next week Ioptron will offer existing ZEQ25GT owners the option of upgrading to the new CEM25. The only change mentioned was to stepper motors from servo motors. I'd love to see more details about this. Stay tuned.

[kalasinman]

Translated from Chinese website;

Extremely quiet central equatorial balanced
GOTO weight saving of 60%
The use of low -power stepper motor
New electronic components from CEM60 's ( ? )
Payload of 27 pounds 12.24kg (ZEQ25 11.4kg)
Body weight of 10.4 pounds 4.71kg (ZEQ25 5.3kg)
8408 upgraded version of the manual can use the new commander
EC has a real-time version of PEC

[kalasinman]

"Real Time" seems to mean that no guiding is required for PEC, but whether results can be recorded isn't clear.

[Zakalwe]

"Real Time" seems to mean that no guiding is required for PEC, but whether results can be recorded isn't clear.

The EC version of the CEM60 has high resolution encoders. These are supposed to correct for periodic error in realtime. However, there are multiple reports of SDE (sub divisional errors) which limits the functionality of the encoder version. From skim reading a huge thread on Cloudy Nights it seems that the SDE issue hasn't been fixed in later firmware upgrades. The EC version seems to be OK doing unguided at short focal lengths (less than 1 metre)but at longer lengths the SDE error causes problems.

Guiding removes this problem, but then you might as well buy the cheaper version that comes without the encoders. This just shows the difficulty for a manufacturer to get high resolution encoders working in cheap mounts. Even in expensive mounts (Paramount, Astro-Physics) encoders aren't easy which might be why those manufacturers don't really offer them.

[kalasinman]

When I get word that the upgrade, indeed the mount is actually ready, I''l ask the question to John at Ioptron Tech and post his answer here.

[kalasinman]

1

CEM60 Firmware Upgrade History

V20140115

Beta Testing

(main board)

V20140214

Beta Testing

(R.A., DEC motor control boards, Hand Controller)

V20140423

Initial release

(HC, main board, R.A. and DEC boards)

V20140526 Firmware upgrade for main board, R.A. and DEC board

V20140527 Firmware upgrade for HC



Improvement of EC version guiding



Fixed the bug that may cause mount stopping tracking randomly;



Fixed incorrect moving speed of 1x and 2x;



Fixed the bug that will cause PEC playback not working properl

y;



Added multi-language interface of HC, Simplified Chinese added

;



Other improvements.

V20140720 Firmware upgrade for main board, R.A. and DEC board

V20140721 Firmware upgrade for HC

New features:

1. Coordinates auto-saving feature added. If the power is lost

by accident while mount is tracking, the

mount will restore its coordinates when the power is back. It d

oes not work while the mount is

slewing.

2. Set Zero Position function added. Now you can manually set t

he mount zero position using hand

controller. Note: The zero position has t be reset after firmwa

re updating, or if the mount losing its

power during slewing.

3. GPS will auto refresh every 6 minutes.

Improvements:



Greatly optimize the size and speed of hand controller firmwar

e.



Number input module of hand controller has been rewritten.



Auto-guiding in both R.A. and DEC axes has been improved.



The algorithm to calculate the position of pole star has been

further improved.



The algorithm to calculate the zero position has been improved

.



Fixed the error that the mount sometime may slew to an incorre

ct position of a star



Fixed the display error after mount parked successfully



Other improvements

V20140825 Firmware upgrade for HC, main board, R.A. and DEC bo

ard

Improvements:



Improved tracking performance of EC model.



Improved guiding performance.



Improved the algorithm of Two Star Polar Alignment.



Using the latest (UCAC4) catalog data for calculating position

of Polaris and Sigma Oct.



Optimize the communication protocol.



Fixed a bug of sometimes PEC recording will fail.



Fixed a bug in calculating position of pole star.



Other minor improvements.

[kalasinman]

The last post relative to these issues on CN was from April this year I believe. A new firmware issued in June according to the above history from Ioptron website.

[Zakalwe]

The last post relative to these issues on CN was from April this year I believe. A new firmware issued in June according to the above history from Ioptron website.

It looks like the June firmware update hasn't fixed the issue:

http://www.cloudynights.com/topic/502593-cem60ecs-sde-improvement-almost-none/?hl=%2Bsde#entry6630437

[kalasinman]

As I'm nowhere near to understanding SDE error, I've decided, as I've been offered the upgrade, what I need and what I don't.

I don't need unguided accuracy.

I do need sub arc second guided accuracy.

Right now I can't record PE, so PEC pretty useless. I need to record PE so I can get rid of it. *note to self.. I probably could be doing this per session now, as I am guiding.

I would love to get rid of "over current error" and related burned motors.

If the stepper motors contribute to ANY of the above, that would be good.

[kalasinman]

Today from John at Ioptron re SDE error  Regarding SDE in CEM60-EC, from customer feedback all except one case the new firmware has greatly reduced and in some case eliminated the SDE. We suspect the only exception might have something else other than SDE. For example, his DEC and RA ripple were the same and symmetrical which was not understandable since DEC should be flat when guiding was off. One possibility was the camera was not orthogonal to either axis then the DEC ripple was actually a portion from RA. We have not heard from him after a few months when we suggested him to check the DEC reading on hand controller (if there was DEC ripple when guiding off, it should show on the hand controller).

[ollypenrice]

It's an interesting thread. It might be titled, 'Do you want to be an iOptron Beta Tester?'

I'm not sure that I do. There are things to like about this firm but so many products, so rapidly redesigned, suggest to me that I don't like their business model. My advice to them (which will interest them not a jot, I fully understand) would be, 'Calm down, produce half as many new products and test them twice as well before bombarding the world with their wonders.'

Olly

[kalasinman]

Today from John,

"Yes, the CEM25 is the same as ZEQ25 regarding PEC. The recording does not permanently save. The difference is CEM25 can record PE without autoguiding.

 

I think the PEC for ZEQ25/CEM25 is purposely designed so to differentiate it from iEQ30/Pro."

Agreed with your view of the business model, Olly  Having never owned a telescope or mount before, or even known anyone, I guess I could have done worse. In retrospect, as problem solving is an effective learning device, I've learned a lot. Many of the problems I've had were not else but my inexperience. A slightly fussy critter, but it does punch above it's weight.

[StuartJPP]

I had the "original" iOptron ZEQ25-GT...my review is in the equipment review section...

iOptron have some serious QA issues...agree with Olly...get the things working properly first before thrusting yet another incremental update on the poor consumer.