Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

CEM25Ec to CEM40EC

  • Please log in to reply
15 replies to this topic

#1 FrankSD

FrankSD

    Sputnik

  • -----
  • topic starter
  • Posts: 37
  • Joined: 02 Dec 2017
  • Loc: San Diego, CA

Posted 05 August 2020 - 12:01 AM

I've only had a few nights with the new mount and I probably should wait till I can give a more authoritative review. . .but for what it's worth, here's my perspective.

 

The CEM25EC was my first mount.  I've had it for two years and until a few months ago I didn't guide it at all; just went with the tracking.  Which was pretty good: I generally ran 2-4 minute subs with my 4-inch refractor and the stars looked pretty round.  Keep in mind I'm new, though.  I really liked how quiet the mount was (is); I found it pretty easy to work with.  And my lower back really liked how small and light it is.  I'd still recommend it to anyone except that, wow, this new CEM40EC just blows it away!  Only a little heavier but far more professional in it's fit and finish.  Where the little one had plastic knobs and mushy belt drives, this one feels solid and secure.  I had mixed success with the SharpCap polar alignment (possibly due to operator error) but the iPolar alignment is much easier and seems to do a great job.  The hand controller is bigger with more options and better features.  The mount has a couple of USB connections and you don't even need a hand controller (though after a couple of collisions with my CEM25EC I always keep the controller and the Stop switch in hand during a big move).  The cable management system isn't what I'd hoped but it's a step in the right direction.  The mount holds and moves my TeleVue np101is and Skywatcher SkyMax180 very well and I'm confident I could use a much heavier scope.  (The CEM25EC didn't seem to have any problems with those, either.)  I've only had a couple of semi-clear nights but the tracking looks good.  I have tried unguided but PHD2 doesn't seem to be working very hard, so that's a good sign. 

 

With the old CEM25EC the mount would ram into those little azimuth pins on the side, hence my cheesy rubber bands to keep them out of the way.  Overall the mount worked great, but there were little things like that that gave it a cheap feel.  The new CEM40EC has none of that--and it doesn't ram into itself. 

 

It came with the new LiteRoc 1.75inch tripod instead of the 2-inch I'd bought with the CEM25EC.  The extensions are the same diameter as the old 2-inch and it seems every bit as stable. 

 

Hope this helps somebody.  I put off buying the new one because hey, the old one worked pretty well.  But technology advances and the new mount shows it. 

Attached Thumbnails

  • IMG_7598.JPG
  • IMG_7599.JPG
  • IMG_7600.JPG

Edited by FrankSD, 05 August 2020 - 12:17 AM.

  • dswtan, jeremiah2229, davidparks and 2 others like this

#2 FrankSD

FrankSD

    Sputnik

  • -----
  • topic starter
  • Posts: 37
  • Joined: 02 Dec 2017
  • Loc: San Diego, CA

Posted 05 August 2020 - 12:08 AM

One more thing. . .do all mounts try to kill your camera?  Both iOptrons seem determined to swing the RA axis full-tilt before moving the Azimuth.  That means a meridian flip can get very exciting as the camera goes racing towards a tripod leg.  And the mount motors don't cut out after the collision; they just keep grinding away.  At least, that's how it went on my old mount.  After a few experiences on my CEM25EC (my ASI294 survived) I bought the iOptron Mini-Pier for it and was glad I had.  The TeleVue np101is with focuser and extensions is kind of long.  I can't guarantee the mini-pier will assure clearance every time--but as you see, I immediately added one to my new mount.

 

IMG_7602.JPG IMG_7601.JPG


Edited by FrankSD, 05 August 2020 - 12:08 AM.

  • jeremiah2229 likes this

#3 dkb

dkb

    Viking 1

  • -----
  • Posts: 524
  • Joined: 23 Jul 2008
  • Loc: Minnesota

Posted 05 August 2020 - 11:11 AM

Thanks for the nice comparison FrankSD!  I'm sure it is helpful for those trying to determine which mount to upgrade to especially for those wanting to upgrade from SkyGuider Pro.  

You mentioned the cable management isn't what you hoped for, can you elaborate on that?


  • FrankSD likes this

#4 davidparks

davidparks

    Viking 1

  • *****
  • Posts: 708
  • Joined: 20 Jul 2017
  • Loc: Battle Creek, MI - USA

Posted 05 August 2020 - 11:42 AM

Great comparison!  I've had the CEM40 for about a year, but recall at the time debating whether to have gone with the CEM25, which still seems like a nice mount for that weight class.

 

I've never had issue with crash whether going 180 across the sky, or full meridian flips, without pier, with a full imaging train (rotator, flattener, filterwheel, ASI2600... hopefully you'll never see a crash either! 

 

Even the non-EC version is a great performer, you should find your EC a joy to use waytogo.gif


  • FrankSD likes this

#5 rlillard

rlillard

    Sputnik

  • *****
  • Posts: 44
  • Joined: 30 Apr 2019
  • Loc: Tucson, AZ USA

Posted 05 August 2020 - 10:02 PM

iOptron has been refining their technology with each new mount.  I have a CEM25EC on order but it might not be too late to change to the CEM40EC.

 

What is the introduction sequence of the CEM mounts?   

Is the 40 design newer than the 25 ?

 

By one reading the CEM25EC web page implies there is a new second CEM25 but they don't say how new or new compared  to what.

Is there a second generation CEM25 ?

 

My current light weight grab-n-go is the Sky Guider Pro.  It was my first mount and I feel like I have learned everything it has to teach me. I just want a low payload mount that is smarter that the SGP and would choose the 40 over the 25 if the 40 is a newer design.

 

Thanks



#6 FrankSD

FrankSD

    Sputnik

  • -----
  • topic starter
  • Posts: 37
  • Joined: 02 Dec 2017
  • Loc: San Diego, CA

Posted 06 August 2020 - 02:00 PM

Thanks for the nice comparison FrankSD!  I'm sure it is helpful for those trying to determine which mount to upgrade to especially for those wanting to upgrade from SkyGuider Pro.  

You mentioned the cable management isn't what you hoped for, can you elaborate on that?

Glad you found it helpful, dkb.  I'd hoped it remove all the dangling wires and velcro wraps but I can't figure out how to do much with it.  There's a little teeny hole in the top of the mount, barely big enough to fit a USB cable.  And it would crowd the wires that are already in there and looking vulnerable.  I'd thought I'd be able to stick a USB and a couple of dew-heater cables in there but not so.  I attached a pic that might give you an idea. 

 

On the back of the mount there's a couple of USB ports and a 12v output.  But the 12v is limited to 3 amps; ZWO says I need all that just for the ASI2600.  Right now I don't have anything else to attach but there's no margin if I did.  The USB port on the mount is only USB2; both my ASI cameras have USB3 ports and I won't be able to take advantage of that. 

 

So. . .not great, but it's still a help.  I use the 12v output on a short cable to the ASI2600, so that removes one dangling cord.  I've only done a couple of shoots with it but the ASI2600 and the ASI294 seemed content with a USB2 connection; no problems downloading, etc. 

 

Keep in mind that I'm pretty new to this, so you might find better info from more experienced shooters.   But overall I really like this mount, so don't let these quibbles dissuade you. 
 

Attached Thumbnails

  • IMG_7609.JPG


#7 FrankSD

FrankSD

    Sputnik

  • -----
  • topic starter
  • Posts: 37
  • Joined: 02 Dec 2017
  • Loc: San Diego, CA

Posted 06 August 2020 - 02:09 PM

iOptron has been refining their technology with each new mount.  I have a CEM25EC on order but it might not be too late to change to the CEM40EC.

 

What is the introduction sequence of the CEM mounts?   

Is the 40 design newer than the 25 ?

 

By one reading the CEM25EC web page implies there is a new second CEM25 but they don't say how new or new compared  to what.

Is there a second generation CEM25 ?

 

My current light weight grab-n-go is the Sky Guider Pro.  It was my first mount and I feel like I have learned everything it has to teach me. I just want a low payload mount that is smarter that the SGP and would choose the 40 over the 25 if the 40 is a newer design.

 

Thanks

Hmmm. . .I can't give you much on the history or sequence of iOptron mounts.  The CEM25 is definitely older than the CEM40 series.  I think it's about 3 years old now, and the 40 came out last year.  The CEM60 was in between and I think the company has been learning and building on previous models.  I don't know anything about a second version of the CEM25.  If it incorporated the advances I'm seeing in the CEM40, it'd be great.  Light, easy to carry assembled (out to the backyard, anyway) and overall it worked great for me.  I do like the bigger and better hand controller, and some features like the find-zero-point.  The counterweight post is so short I had to add a 5-pound weight that I don't need on the longer post of the CEM40.  Don't forget that it comes with the iPolar camera that makes polar alignment so easy.  I considered buying an iPolar for my CEM25EC but they're not cheap. 

 

Hope this helps.  I've been very happy with the CEM25EC, overall; it was my first mount and I found it very user-friendly and capable.  I'm kind of a technology junky, though, and wanted all the new tech on the CEM40--and I wasn't disappointed.
 



#8 davidparks

davidparks

    Viking 1

  • *****
  • Posts: 708
  • Joined: 20 Jul 2017
  • Loc: Battle Creek, MI - USA

Posted 06 August 2020 - 03:07 PM

Yep, that’s the hole...

 

Check page 9 of the online manual: https://www.ioptron....EM40_Manual.pdf

 

There is a plastic cap between the iPolar and USB ports that comes off to reveal one pathway, the other is just below that on the “bottom side” of the same axis.  They feed thru up to the hole that you have pictured... you just gotta squeeze what you have thru there.  I have 2 dew strip power cables running thru there.  Once the wires come up out of that hole you have pictured... you’ll see that they will then run underneath a mounted dovetail bar.... again not much room, but they fit in the little channel/space under your payload’s dovetail bar.

 

I run the ASI2600 (cooling on), Sesto Senso Focuser, and Optec Pyxis LE Rotator all from the saddle power port... my ASI2600 has never pulled 3amps even at full power.  However, I do run the 2 Dew power lines thru the mount down to a Pocket Powerbox Advance so that they are not on that saddle passthru power line.

 

Descriptively, for power, “down below” I have a lithium battery feeding power to the Power Pocket Box Advance, which in turn feeds power to the mount (and hence to the passthru saddle).  Also, the PPBA has two ports for directly connecting the Dew Strips, which is why I have those 2 cables coming down thru the wiring holes.  For USB, I have the PPBA connected to the CEM40, the iPolar, and the USB Passthru Saddle (all at bottom of DEC axis)

 

Up on top, I have the saddle passthru power connected to the ASI2600, Sesto Senso, and Pyxis Rotator, using 5.5mm x 2.1mm Y splitters.  I have a small 4 port USB thin hub connected to the saddle USB, for plugging in the ASI2600, Rotator, Guidecam, and FlipFlat (the Sesto Senso plugs in to the ASI2600 usb hub),

 

I never have issues, this runs like a dream...

 

Just so you know, before I acquired the Pocketbox Advance, I used to power dew strips from the same 12v Y-splitted line coming out of the saddle passthru, along with everything else I’ve mentioned...  and even with the ASI2600 at full cooling power and both dews at full power my largest draw stayed under 3amps.

 

I would never tell you it is OK to go over specs... meaning I know that ZWO says the ASI2600 needs 3amps...   I’m just telling you what my experience has been.  I have an in-line power monitor so I can make these determinations for myself and feel safe with my setup... so... grain of salt, and do what you think is best for your gear.


  • dkb and FrankSD like this

#9 dkb

dkb

    Viking 1

  • -----
  • Posts: 524
  • Joined: 23 Jul 2008
  • Loc: Minnesota

Posted 06 August 2020 - 05:58 PM

David Parks, do you have pic of your wiring arrangement especially as it goes into the mount and out through the saddle?  



#10 FrankSD

FrankSD

    Sputnik

  • -----
  • topic starter
  • Posts: 37
  • Joined: 02 Dec 2017
  • Loc: San Diego, CA

Posted 06 August 2020 - 10:21 PM

Thanks, David; good to know.  I've suspected I could remove the CMP and make more room to fit the cables through.  I'm still nervous about those thin little wires, but I'll work up my courage and see how it goes.  I like the idea of running my dew heater cables through there rather than velco'd randomly. 

 

So you don't plug your ASI2600 into that USB2 port on the back of the saddle?  That's good data.  If I ever see a clear sky again I'll keep an eye on how mine is working through it.  I second dkb's motion of posting a pic of your rig!

 

On the subject of collisions. . .my TeleVue np101is with it's adapters and spacers hangs the camera back  about 22 inches from the middle of the saddle.  I suspect that's more than most refractor rigs and definitely more than any reflectors, and more than iOptron planned on.  Here's a not very useful photo of it.  I mentioned earlier that my CEM25EC required another 5 pound weight that you won't see here; that was after I added the guidescope/camera and swapped that useless Celestron red dot finder for a Telrad. 

Attached Thumbnails

  • Televue rig small.jpg


#11 davidparks

davidparks

    Viking 1

  • *****
  • Posts: 708
  • Joined: 20 Jul 2017
  • Loc: Battle Creek, MI - USA

Posted 06 August 2020 - 11:39 PM

4C055485 5FC5 4FEC A4CC A7B3EDF75B5B
 
2 Dew power lines going in to the bottom of the DEC axis
38B1B2B5 D806 4FCC B9C1 00D3AABDA614
 
2 Dew power lines coming out of the saddle hole... mind the small wires
2B208F7F 785F 4088 9083 0C4EA31C82F6
 
With the dovetail back in the saddle, the dew power lines sneak out from under thru a channel just under the dovetail
67AA4769 6493 43EF 8C26 E3D25EDCE7DE
 
This one just happens to kind of show the thin 4-port USB hub that i have plugged into the saddle usb
The ASI2600, ASI290, FlipFlat, and Rotator are all plugged in to that (and then into the saddle usb)(focuser into the 2600)
F81E5FB0 29B5 48F0 9E57 FF3CF5D579B3

Edited by davidparks, 06 August 2020 - 11:45 PM.

  • dkb likes this

#12 FrankSD

FrankSD

    Sputnik

  • -----
  • topic starter
  • Posts: 37
  • Joined: 02 Dec 2017
  • Loc: San Diego, CA

Posted 07 August 2020 - 12:05 AM

Those pix are very helpful, David--thanks.



#13 B 26354

B 26354

    Surveyor 1

  • -----
  • Posts: 1,564
  • Joined: 05 Jan 2017
  • Loc: Southern California semi-desert (NELM mag 5.3)

Posted 08 August 2020 - 07:57 PM

Is there a second generation CEM25 ?

The CEM25P is the 2nd gen 25. It has improved periodic error correction.



#14 aposadao

aposadao

    Lift Off

  • -----
  • Posts: 1
  • Joined: 28 Aug 2020

Posted 28 August 2020 - 07:30 AM

Greetings from Colombia. Since I am at 5 degrees latitud I was looking forward to buying the CEM25P, which allows to work down to 0 latitud. Most other brands go down to a maximum of 10 or 15 degrees latitud. But yesterday it shows discontinued in their web page and BHphoto. Do you guys have any information on what is going on? Are they coming out with a new version? The CEM25EC is still available, but it is double de price of the CEM25P.

I am in distress!!



#15 B 26354

B 26354

    Surveyor 1

  • -----
  • Posts: 1,564
  • Joined: 05 Jan 2017
  • Loc: Southern California semi-desert (NELM mag 5.3)

Posted 28 August 2020 - 11:34 AM

Greetings from Colombia. ...I was looking forward to buying the CEM25P....

PM sent.



#16 mewmartigan

mewmartigan

    Apollo

  • *****
  • Posts: 1,283
  • Joined: 02 Jul 2008
  • Loc: outside of Pittsburgh, PA

Posted 28 August 2020 - 12:31 PM

David, I am glad to hear you are running so many things off the one saddle power jack. I have my asi2600 plugged into it but was afraid to split and run my autofocuser too. Glad to see it works as that will be one less power cord to run up through my mount.


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics