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Thanks for that explanation, that is the clearest one I've heard about this topic yet. Seeing condition measurement still feels like a bit of a mystery for me. I'll have to take some time reading up on it using some of those terms for my google searches. My understanding right now is that the guiding assistant RMS values are the best to measure of seeing conditions, but it sounds like it is also measuring imperfections in the mount. I didn't run the assistant for either of the two nights since my guiding was so good, I didn't want to mess with anything. I just wanted to do some captures, and now I've got an excellent set for G, and a good set for R.?

I've been meaning to get pempro going so that I could look into some of the mounts contribution to the noise, but the only windows machine is my wife's laptop, and I'm not going to abscond that for astronomy. I'm maybe half way there with getting it running under wine...

Yeah, I am totally jealous of you Southern Hemisphere folks for objects such as this! The bulge of the Milky Way passes right through zenith there and makes for some spectacular images.

From 22 degrees it's pretty impressive. It passes at the zenith here and that would still be an excellent field.

Jamie,?

The Point Spread Function, which is the way a point source of light such as a star is rendered, depends on the Airy disc size of your scope, the guiding, and the seeing. Mathematically, it is a convolution of these three things. The guiding is affected by seeing of course, but also by mechanical issues. When you run Guiding Assistant, PHD2 will give you an estimate of high frequency star motion; that is an estimate of the extent to which things such as seeing and high frequency vibrations in the mechanics of your mount affect your overall RMS. When I ran Guiding Assistant, I got high frequency star motion RMS values of about 0.27", while my overall guiding was about 1". So in my case, the rest of the impact on guiding RMS came from mechanical properties of my mount and set up - PHD2 cannot correct for high frequency motion since its pulses are on time scales much larger than these motions.

The most likely thing is that your seeing was better. A seeing number of 2" has the same impact on your star size as a guiding RMS of about 0.85" in a long exposure sub. So if the seeing improves significantly (say to around 1" on a great night), then your overall star size will be reduced even if the guiding RMS is slightly worse.

Arun

So I had an absolutely awesome night last night photographing R for the Iris nebula. My guiding was looking real nice, usually in the 0.7s, but dipping into the mid? .6's. not a lot of corrections so I was expecting great photos. And they were great, but as I went through my green photos from the nights before trying to choose the best one for pixinsight , most of the green shots from the night before had sharper rounder stars. And the guiding was good, but more like 0.9 0.8 RMS, but not as good. From memory it also had more jagged corrections. So RMS is a great tool, but not everything. I'll have to look at the logs to see what might account for the better results. My guide exposures may have been longer...?

It looks like this was a mount problem.? I adjusted the RA worm block and it looks resolved.? I just ran 30ea 3 min subs and everything looks OK.? I dithered every 3 subs as before.

I just got done working on my mount.? It felt like the RA worm was shifting side to side so I adjusted the outer worm block.? I need to do testing tonight.??

FYI - Last week I posted an issue about side to side play in my RA.
/g/Losmandy_users/topic/rotational_play_in_gm811g_ra/74810829?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,0,74810829

That's on my list of things to try tonight - no dithering.

FYI

I've often thought about a camera to do remote monitoring, and also sky monitoring (with the same camera).
I usually don't realize that the clouds have found me until I go out and see the sky has closed for the evening.? :^(

I'm beginning to wonder at what point my Baby Dell will turn into a Baby Huey though. By over taxing the processor and WiFi.

Sorry.
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SonnyE


(I suggest viewed in full screen)

Don't know Jim. It appears to be consistent, two distinct images.
Have you tried with no dithering? Try eliminating one thing at a time.

I had "Space Ships" for a time. My stars looked like the flying saucers in Scott and Brian's videos.
I turned on PEC and let it run. fixed that problem.
Also, I did a factory reset on my Gemini 2, some puzzling behaviors stopped with that. (It can't hurt)

You aren't drinking a bad bottle of whiskey now, are you?
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SonnyE


(I suggest viewed in full screen)

BTW - The above image is of Vega.

I went back to a previous beta release (014) of NINA and the same thing happened after dithering.? Its always in the same direction.? I increased the NINA PHD2 Max Settle Time from 10 to 16 but it was too windy to do any testing.? This is the first time this has happened using NINA or SGPro.? Also om my mount.

Is this mount related or imaging SW.? Is this RA or DEC related?? It looks RA related.

Another image below.

Well, this platform isn't really meant for much more than link sharing.
More meant for information sharing.

I usually share mine with friends on a Photography forum.

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SonnyE


(I suggest viewed in full screen)

Beautiful, Thank you.

HAPPY SKIES AND "KEEP LOOKING UP" Deric

Why would my GM811G be doing this?? There's very little wind, guiding is OK and nothing is moving around.? I just upgraded to NINA 1.10 Beta 015.? This has never happened before.

I am dithering every 3rd image and it looks like its related to dithering.??

Michael Herman has a CG11 and G11 and ...?
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Chip Louie - Chief Daydreamer Imagination Hardware

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Not many people share images here, it seems, but I thought this would be a nice change from the technical issues/problems we discuss here to share what can be done with our equipment. This one is of the Lagoon Nebula that I imaged earlier in the week from a dark sky site about 30 miles away from where I live. I also enjoyed viewing this, the Swan and Eagle through binoculars as I was imaging.



This is about 5 hours total in LRGB. It is a bit low in the sky here, 22 degrees at its highest, so guiding was not as great as with other objects I image.?

Clear skies,

Arun

Hi,
I would like to chat with someone with a good familiarity of the old style G11/CG11 mechanical construction involving clutch tightening, worm and gear adjustment. This is about a specific issue I am encountering. Probably and off-list discussion would be best.

I also wonder whether Rainer is still on the list.

Tom