Hello all

I tested yesterday with parameters set according to the XLS shared by Edward, and (almost) everything worked fine. The flip happened at expected time and the image after flip was just fine. No more runway goto/park as I've seen before.

Now, the "almost" above is related to the Plate Solve i've been doing and how Gemini apparently works. I've been using OnStep on my GM8 for a couple years and I never had to do any modeling before the session. I would just goto first object, do a plate solve and sync and everything would work just fine after. I've been doing the same with Gemini, but apparently it doesn't like that when?there's no model previously saved.

During my session yesterday, when I tried to do the plate solve, NINA would increasingly move AWAY from the object instead of closer. it tried 10+ times before it failed, and that's where i guess it would go to that park position i mentioned before.?

After noticing this could be the problem I restarted everything, did a 3 star modeling, and the plate solve worked like a charm after that.?

Guilherme

On Mon, Jun 28, 2021 at 4:01 PM Edward Plumer <eplumer@...> wrote:

Change the log to "TRACE" level for the next time. It is not too verbose for a night of use.

--
Edward

Change the log to "TRACE" level for the next time. It is not too verbose for a night of use.

--
Edward

Thanks Brian,

The good news is that my PA was solid all night, remaining around 0.5-1.0 through all my testing.

I still have two issues that I need to figure out.

1. Calibration/GA indicate 3-3.5 seconds of backlash and I should guide only in one direction
2. My RA guiding is not where I want it to be. I am not sure if this is my guide cam scale is just not good enough (6.4 arc sec/pxl) or something else

DEC guiding was awesome all night despite the reports of backlash. Generally around 0.1px (~0.6-0.7 arc secs). There were relatively infrequent corrections and I was really happy. Not sure what can be done about the backlash and if that is affecting RA guiding

RA guiding was generally 1.0-1.3 ish overnight, which is higher than I was expecting. I was not able to get a full 20 min log because when I calibrate at the meridian/equator, the scope moves through a bunch of trees (I kept resetting back and so could do multiple runs)

Toward the end of the night, I did adjust the weight more eastward (even though we should not need to do that) - although with the weight of my rig, it was generally still balanced. This did not seem to really help

What eventually did get the guiding down was to set the PHD exposure to 1.0 seconds (I tried 2.0. 3.0 and 4.0 with no changes)
Once I set it to 1.0, I saw an immediate change. Unfortunately it was almost 3am so I didn't have time to run it for long, but RA got down to around 0.8 which is a much better number

I'm uploading some logs to see if there is anything obvious in them. In a couple, there is a spike halfway through as I touched the mount to try to change the weight balance, or check for snags

There are no real cable snags, but at one point my data/power cables were rubbing on the RA motor cable. I taped that off to the mount (which caused some of the spikes), but id did not seem to make any real difference

I want to truly thank everyone for their help here. I have figured out at least the initial error.

I went back to "debugging school" and started going one step at a time
Used Sharpcap to align, then aligned the "other" way ... alignment went excellent -> poor
Did it 2-3 more times, same result.
Put a flashlight on the rig and noticed two things

1/ (probably minor) - tiny bit of play in DEC - resolved by tightening the clutch
2/ Smoking gun .... when I attached the OTA to the plate, the screws of the focuser got in the way of doing it the way I wanted. I loosened the ring on the scope to try to get it to fit but it still wouldn't Turns out i never tightened that up fully and there was wiggle

I got a wrench on the knurled knob of the ring and clamped it down and now PA at least is solid in Sharpcap no matter what side I start from

Now i am going through the PHD baseline to see what that shows ( I reset defaults in the PHD algorithms page)

I do have one more question - the TVC parameter on the mount is set to 5 (it came that way)
My understanding is it needs to be zero. Should I change it and re-calibrate and redo guide assist ?

Hey Michael,

How can I get one of those hand controller mounts that attaches to HD tripod??

Jason

On Mon, Jun 28, 2021 at 12:12 PM, Brian Valente wrote:

i wasn't sure if your dob was for imaging or visual, if visual it would be fine

?

Brian,

Strictly imaging. Did you see the pictures Michael posted earlier of him setup? Look at those weights!

Peter