3 replies to this topic

[Darth Riker]

Hi all,

 

I have a C8 SCT with a f/6.3 Reducer and ASI294MC Pro camera (with ZWO UV/IR Filter) and ASIAIR Plus 32GB using a HEQ5 Pro mount.

 

I do unguided EAA with no more than 30s exposures for at most 30 minutes duration in Live Mode for Live Stacking.

 

Can I use my setup for unguided EAA on the AM5N (or other harmonic mount) instead of the HEQ5 Pro mount?

 

Cheers.

Edited by Darth Riker, 02 October 2024 - 08:49 AM.

[scanner97]

Seems like most sw mounts don't give a PE spec.  For the AM5N, it's +/- 10 arcsec.  The AM3 is +/- 15.  I've also seen quite a few statements that 30 seconds unguided was about the best someone could get with an original AM5, which was +/- 20.  I think you'll be fine, but I'm sure folks who are actually using various mounts will weigh in on their own unguided times.

 

Good luck!

Edited by scanner97, 02 October 2024 - 07:56 AM.

[GazingOli]

Yes, you can. At least I do! I got the same scope and same camera, except that I am using a Starizona reducer / corrector, which brings the C8 to f/7.1

 

 

I am using an iOptron HAE 29. The EvoGuide scope is just for widefield EAA, never guided so far.

 

CS.Oli

Edited by GazingOli, 02 October 2024 - 10:53 AM.

[mgCatskills]

Hey, DR.

 

I use an EdgeHD 8" at f/10 unguided on an AM5 mount using SharpCap with up to 30s exposures.  We have the same camera.  It works fine, although I would have some concerns using an ASIair.  Here are the issues,,,

• I try to achieve PA error at 2' or less.  Still, I can get some drift.  SharpCap has a feature where it will recenter the stack if it detects drift of more than x pixels... I usually use 50.  On a typical evening it might reset once every 15 minutes or so.  Will an ASIAir do that?
• While tracking is quite accurate, generally, there is the chance of semi-periodic spikes.  You can deal with that by setting a pretty tight FWHM filter in SharpCap... On the odd spike it will get filtered out.  In my case, made more feasible by observing off of a 12" concrete pier that normally delivers extremely consistent FWHM measurements.  Does ASIair support FWHM filtering?
• Dithering is very important with an EQ mount to avoid walking noise.  SharpCap has a setting where it will dither x pixels every y minutes of cumulative exposures.  Will an ASIair dither without guiding? 

If you can deal with those issues with your ASIair, I would say no problem, esp given the improved accuracy with the AM5N.  If not, consider coming over to the Dark Side (i.e. SharpCap). 

Edited by mgCatskills, 02 October 2024 - 06:46 PM.