Asiair Calibration Settings for Using and OAG

Ok, I’m using 5 sec exposure but I suspect it’s my calibration settings or maybe even my focus. I am getting somewhat elongated stars.
my aggression settings are set to 65 and 65.
see the pic below for my calibration settings.

It's kinda hard to say what's "best" as it can be pretty variable depending on your setup.

When I have guiding issues I usually just clear the calibration and let it redo it, that almost always fixes it.

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I found I could not get the guiding performance I was looking for with the limited PHD2 lite software running on the ASIAir Plus for my EdgeHD 8, ASI533MM, and EQ6-R Pro configuration.

I moved to N.I.N.A. with the full capabilities of PHD2 and pleased with my ability to optimize my guiding.

Moving up to the longer focal length of the EdgeHD 8 showed me the ASIAir was no longer an acceptable solution for that focal length per my personal standards. Others may have different views and experiences as it should be.

Bill, when you moved to NINA, how did you make the connections to your computer? I have all the software installed, I just don’t know what I need to make the connections. (Cables, external USB hub etc.)

id really like to try and use Sharpcap or Firecapture for planetary imaging. I’m just not sure how to connect to the computer and get away from Asiair.

Davesview, 

what’s the Calibration Step you use in the settings?

Gunder Strømberg:

DavesView:
sctom

Hi. Reading everyting I can come over about guiding as my mine vary alot.
You write that You got Your settings from sctom. May I ask where I can find "sctom"?

Sctom is a user on Astrobin.

Edit: Ooops! sctom is a user on CloudyNights. The following discussion:
https://www.cloudynights.com/topic/842943-zwo-am5-owners-club/page-64#entry13198537

In fact read EVERYTHING on their website.

Great read!

DavesView:

Gunder Strømberg:

DavesView:
sctom

Hi. Reading everyting I can come over about guiding as my mine vary alot.
You write that You got Your settings from sctom. May I ask where I can find "sctom"?

Sctom is a user on Astrobin.

Edit: Ooops! sctom is a user on CloudyNights. The following discussion:
https://www.cloudynights.com/topic/842943-zwo-am5-owners-club/page-64#entry13198537

Sctom mentions locking the primary mirror on the SCT. I didn’t know you can still focus with the primary mirror locked. I was thinking that would break something.

Collimation ran me away from SCTs. I have never used one to any satisfaction, even though I have one. But yeah, my understanding is to unlock the mirror, then focus, then wonder why I can't get a decent image.

Jerry, how do you determine those numbers to plug into that formula?

- Resolution in arc-seconds per pixel? (Is this with the .7x reducer?)

- How do you find Sidereal Rate?

- How do you find Ground Guide Rate?

You have to know the pixel size of the sensor in the camera you're using and the telescope focal length you're using.  You can do that here:  https://astronomy.tools/calculators/ccd

Once you know that number, substitute that number for the r value.  The Sidereal rate is always going to be 15. 
https://www.google.com/search?client=firefox-b-1-d&q=sidereal+rate+in+seconds

Your guide rate (gr) is set in your app that comes with your mount.  It's usually .5 seconds, but you'll have to check. 

Take a few moments to study the formula and you'll get it.  It's not very complicated.  

The calibration step size doesn't need to be perfect, as so long as it's close to what it should be.  For example, the formula I use says I should have a calibration step size of 909 but PHD says it should be 950.  Either way, there are so many other factors (seeing and sky conditions, guide camera exposure time, RA and DEC aggression, focal length) that the calibration step size just needs to be close...

I have the exact same setup (and AM5 mount). Also struggled with guiding performance in the beginning. I upgraded the guide camera from ASI120MM-MINI to ASI174MM-MINI. Solved all of my issues. (The ASI220MM-MINI may also be a good choice.)

The ASI174 is a bit over-size for the OAG image circle, but that's OK, it guarantees every star projected by the OAG is available for guiding. I'm using bin1, high gain (350), dark library and 2 sec exposures. I don't have it in front of me, but think I'm using 65% aggressiveness. The defaults were too high.

I never messed with the calibration parameters. (But maybe I should look at that?) When calibrating I point the telescope near-ish to the equator and meridian.

I usually get guiding RMS < 0.50" (if it goes over that I start checking stuff, but it's usually poor seeing). I've occasionally seen RMS down to maybe 0.25" at higher declinations and still air. I think that's getting close to the mechanical limit of the mount.

In the case where there just aren't good guide stars in your OAG field of view, an option you have with the square aspect ratio of the ASI533 is you can rotate the camera 90 degrees and have the same framing, but maybe by chance a better set of guide stars. I've done that a couple times. Just remember to recalibrate.

I have an EAF and don't lock the primary mirror. I find that the OAG compensates for the mirror flop very well. (Also it was my experience with a mini guide scope that the mirror locks did basically nothing anyway.)

Lastly, I use the 48mm diameter T-adapter with the OAG.

Hope that helps.

Bill Poplawski:

Bill, when you moved to NINA, how did you make the connections to your computer? I have all the software installed, I just don’t know what I need to make the connections. (Cables, external USB hub etc.)

id really like to try and use Sharpcap or Firecapture for planetary imaging. I’m just not sure how to connect to the computer and get away from Asiair.

I went the route of a Pegasus Astro Pocket Power Box Advance (PPBA) which is both a power and USB distribution box. I would connect and power devices via the PPBA and connect the PPBA to my laptop. Subsequent to that I replaced my laptop with a BeeLink mini-computer. Subsequent to the BeeLink I now use a PrimaLuce Lab Eagle 5 S. 

If you want to do a Google Meet I'll be happy to discuss in detail. You can reach me via astrochatterpodcast@gmail.com. I can go over cables, etc.

Bill

Thanks Bill, I’m going to stick with Asiair for now.  All that’s a bit out of my price range at the moment since I just upgraded my scope to an edge hd 9.25. I guess one upgrade at a time.