CEM40 OR CEM40 EC

[space3]

Hello everyone 

I'm going to upgrade from  CGEM 

And looking to buy a Ioptron Cem 40, I have been talking to FLO,

But I want to get some opinions on it before I decide, I have been scrolling here and on cloudy nights, but I'm no further on.

What I want the mount for is to run my 100mm Esprit, I want to take unguided images, even 2 minutes would be awsome, my CGEM cannot do this,

But will the non EC version give me this or will the EC version be a better buy for unguided images, 

I haven't got a permanent set up, and this is why I'm doing it unguided, at some point in the future this will change but for now I want to achieve unguided images, 

So any input would be great, many thanks 

Derek 

[Which one is Polaris]

Hi Derek,

I am studying the same question.  I don't have any experience with either CEM40s but do like my CEM26.

So far am leaning towards the non EC version.  Based on reading a lot of discussions:

It seems that the iOptron implementation of encoders has / had a problem related to SDE.

It also seems that the encoders cannot be turned off.

So £1,000 more for what may be a disappointment and ongoing problem is not good.

I am thinking to buy the non EC version and use Guiding if I need it.

 

[Elp]

From what I read about non EC or ec a lot of people who bought the ec versions had regret because something to do with the guiding error cannot be improved upon with the EC versions and not having the option of disabling the encoders. I have a non EC gem28 and it works fine though I do autoguide, typical RMS around 0.4-0.5 at 200mm guide focal length without tweaking with any parameters.

Edited October 4, 2022 by Elp

[Adreneline]

I have a tripod mounted (portable) CEM25-EC which I have used unguided with Samyang 135 and RedCat 51 with exposure up to 300 s with no problems at all.

I have also used it with an RC 6" unguided up to 180 s, no problems at all, although that is getting well on to the stated weight limit for the mount and needs careful balancing.

I have a pier mounted AZEQ6 where guiding is necessary and I happily work with that, but I love the unguided simplicity of the CEM25-EC and have no regrets with my purchase.

I have tried guiding the CEM25-EC using an ASIair but to no advantage - certainly not up to 300s. A good PA and you are good to go!

 

[ollypenrice]

I'd work on the guiding...

Olly

[space3]

3 hours ago, Which one is Polaris said:

Hi Derek,

I am studying the same question.  I don't have any experience with either CEM40s but do like my CEM26.

So far am leaning towards the non EC version.  Based on reading a lot of discussions:

It seems that the iOptron implementation of encoders has / had a problem related to SDE.

It also seems that the encoders cannot be turned off.

So £1,000 more for what may be a disappointment and ongoing problem is not good.

I am thinking to buy the non EC version and use Guiding if I need it.

 

same as yourself I am leaning away from the encoders  after all I have read about them in the Ioptron mounts

best of luck with the mount you go for 

[space3]

59 minutes ago, ollypenrice said:

I'd work on the guiding...

Olly

Thanks Olly

I am accepting this is the best way to go,

have you any thoughts on the StarAid Revolution standalone Autoguider?

[ollypenrice]

4 minutes ago, space3 said:

Thanks Olly

I am accepting this is the best way to go,

have you any thoughts on the StarAid Revolution standalone Autoguider?

I don't know it at all. I'd just use a finder-guider with a camera known to PHD2 and use that. Once it's focused and calibrated (which is easy) it should just work. I have never found guiding difficult.

Olly

[newbie alert]

On 28/09/2022 at 18:11, space3 said:

Hello everyone 

I'm going to upgrade from  CGEM 

And looking to buy a Ioptron Cem 40, I have been talking to FLO,

But I want to get some opinions on it before I decide, I have been scrolling here and on cloudy nights, but I'm no further on.

What I want the mount for is to run my 100mm Esprit, I want to take unguided images, even 2 minutes would be awsome, my CGEM cannot do this,

But will the non EC version give me this or will the EC version be a better buy for unguided images, 

I haven't got a permanent set up, and this is why I'm doing it unguided, at some point in the future this will change but for now I want to achieve unguided images, 

So any input would be great, many thanks 

Derek 

Hi Derek, nothing scarry about guiding.. , try it on your cgem while you wait to decide on the ioptron.. those difficult 2 min unguided subs will turn into 10 mins quite comfortably, just need a rs232( same cable as the firmware update one) and probably a rs232 converter to usb cable.. simple...

[david_taurus83]

Yes guiding all the way. I had an iOptron CEM25 and though it was a good mount and could perform very well, I did have to open it up to adjust belts, grub screws etc. To me, this is an acceptable compromise for a mount that cost me £700 new but I would really question the QC you get on one of these considering the premium you pay for the EC versions. Esprit 100, while not a long focal length, it's a heavy scope and I need 2 counterweights on my pier mounted AZEQ6 to balance it so I would question the CEM40EC's ability to manage that as well without guiding. As mentioned above, get a small 32mm guide scope and an ASI120 mini and give guiding a go with your current mount. If guiding isn't for you there's always someone who will snap up the camera and guide scope.

[space3]

Thanks for all the advice, I will look into guiding my CGEM,  and see how that goes.