Since so many people often post with questions and problems, I just wanted to say I another night of stellar performance from my G11 last night! 4 hours of the Eastern Veil with incredibly good guidance performance (<0.30).

Love this mount!
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Rick Paul
Tucson, AZ

开云体育

By focusing on balance, cable management, etc. I can get around 0.7-0.8RMS on good days - meaning no wind. I'd like to improve that even more if I can. I still need to post my baseline guide logs like Brian suggested.

Just to be clear, this is 0.3" and not 0.3 pixels?? If so, wow.? The best I've ever achieved is 0.6", though usually average 0.7-0.8" (of course my skies aren't your skies).

Keith

I think that is a point worth clarifying ie., 3 arc seconds or 3 pixels. The number PHD2 reports in parenthesis is the guiding in arc seconds and the more meaningful number. the 0.7-0.8 RMS number I mentioned is in arc seconds. Yes, 0.3" would be an amazing number!

I'm settled in with my GM811G HD and enjoying my Summer skies.
I don't fuss about figures. Instead I judge by my results, and I'm doing great there.
There are far to many variables between us and our objects to debate the variances of graphs and charts.
I recently replaced PHD2, because mine became corrupted. It was Easy-Peasy, done at the mount over WiFi.
It practically set itself up.

Tonight I have up to 95% clouds predicted.
Just peachy!

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SonnyE


(I suggest viewed in full screen)

Yes, wanting to quantify things is a wacky idea.

Keith

Different people have different approaches to this, which I respect. For me personally, quantifying things has been a big help. While there are many variables, several of them lend themselves to be quantified and doing this has helped me get more consistent results.

With respect to guiding - at the first cut, as long as guiding RMS is better than your image scale, you're better off worrying about other issues. Today, I image at 480mm with an ASI1600, which is 1.6"/pixel. If I get 1.1" RMS on a bad day, I still shouldn't be focusing on guiding - I won't really see the improvement in my images. But I am soon migrating to a 10" Newtonian which has a focal length of 1000 mm. That's an image scale of less than 0.8"/pixel, and I can pretty much guarantee that if I get 1.1" RMS guiding, I am going to, at best, lose resolution, and at worst, get egg shaped stars if guiding in one axis is worse than the other. That would make me sad, One approach for me is to buy a mount that costs 3x as much as my GM811G and be guaranteed of great results at that focal length, but the other is to see if I can improve the current equipment's results with some effort. Hence my interest in whether Richard's number is 0.3" RMS or 0.3 pixels. If I know that my mount is capable of consistently being guided to, say, 0.6-0.7" RMS, then that would justify me putting continued effort into improving guiding. Other imagers I work with do get these numbers from where I am, but they also use much more expensive mounts.

Under sampling images are certainly a great way to be able to ignore objective PE error numbers. The lost detail is not and cannot observed due to having huge circles of confusion and soft images that if you stand far enough back from look okay.?

The current DSO best practices seem to be a sample rate that is 2.5 times better than atmospheric. This is coming down from the best planetary imagers in the world using lucky imaging techniques which oversample at even higher rates and may be trending up.?

This requires objective knowledge about a mount's error rate. I learned this back in my studio days shooting cut sheet 4x5 macros from a 25 pound tripod that had to be reshot. I used a 400 pound camera stand for second session and the job was accepted.?

Just saying.?

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Chip Louie - Chief Daydreamer Imagination Hardware

You are not quantifying things if all things are not identical.
And none of us have exactly the same things. So anybodies results are never the same as another.

On top of that, none has laboratory grade, certified and tested quantifiers. There will always be differences.
So Your results can never weigh against another's results.
They are your personal results, at your particular place and time, with your atmospheric differences.
Including how you stick out your tongue. (Left, Right, or Middle.)

That's why professional labs share samples with each other to test their results against each other.
And I sure don't see that in this group.
Including any considerations of repeat accuracy.
[edited by moderator]
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SonnyE


(I suggest viewed in full screen)

SonnyE,

I'm not sure what you are saying here. Are you saying the PHD2 PE data people use to debug and refine their mount's tracking is not valid and the data cannot be compared between mounts???

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Chip Louie - Chief Daydreamer Imagination Hardware