Block preview

[Jamesmd]

Hi , I’m new here and I’m starting to understand this great software, so I don’t have any authority tos ask for anything , BUT , I've had one same thing happen a lot of times and its very frustrating .

In the HDR module I first apply Context s and quality , and later tweak things , if I have a large context and Q it takes a lot of time to do it , but I prefer to get it done and evaluate seeing the hole image .

That’s all great, but if you accidentally touch the trackpad or mouse and hit a pixel !!!!! It asumes it’s a new preview and I have to go all over the 20 or 30 min again ….

In this module it would be great if once you hit all, if you click on image it would ask are you sure you want to change preview area , or something .

I imagine this is a stupid request and not anything important but it can make your day

Thanks ,
James

[hixx]

Hi James,
Welcome!
Regarding the new HDR (and all other Modules) You'll find excellent descriptions in the USER NOTES section of the forum: viewtopic.php?f=12&t=2435

Rendering time will increase exponentially with context size. To speed things up, I suggest using a small context size (around 25-30) and low quality first. Remember, a context Size of 30 relates to a "detail size" of 1000 in the ST7 module. Remember HDR is about working out local stretching for smaller details. To optimize local stretching for larger Details, better use Contrast. Use the presets and tweak from there. They usually work pretty good for standard use cases.

You'll find great tips in the User Notes viewforum.php?f=12 and in the Unofficial manual in download section: https://www.startools.org/downloads


Clear Skies,
Jochen

[Mike in Rancho]

Hi James,

30 minutes, wow!

You'll have to let us know what you are doing in HDR, along with maybe your system specs. Oh and the size of the file you are working on.

As Jochen stated, you might be increasing the context size when that really isn't necessary in new HDR. In fact, decreasing may be a better option - both as to the time needed to process as well as the detail you want to reveal.

If you are really oversampled, bin down to something more reasonable. Absent cropping situations, I almost always bin at least 50% from my APS-C files (more or less 6000x4000) and process in the general range of 2000-3000 wide. But different targets and the sampling of your rig may require different strategies.

Quality can probably be left on low or medium, the improvements are still quite good. The most recent ST release actually starts me out at low now as the default, based on my CPU's 4 cores and 8 threads (even though it's a quite decently fast i7, GHz-wise). For a while I was immediately changing it up to medium, but typically now I don't bother.

As far as a preview box, gosh I don't think I have used one of those since 1.6, and kind of gave that up with the advent of GPU-accelerated ST. In fact I forgot it was even there. Some may still need that though, so really I think just keep your pointer away from the image! I can't think of when I have a need to click on anything in there anymore...except SVD blue boxes and mask making...but those don't trigger previews.

If you have some spare time and want to read through a previous discussion full of questions, analysis, experiments, and various handy factoids regarding new HDR, you can try this thread here (only 4 pages, not too bad): viewtopic.php?f=4&t=2357

[Jamesmd]

Hi , thanks for all the info .

I really was just testing and comparing how things changed with different settings , I thought I’d go thru everything trying everything .

And many times I accidentally hit on the image and it started recalculating all over again . … nothing serious but fustrsting , I just thought it would be a good idea if you could have the possibility of getting asked before it recalculates all again.

I was experimenting with a big image, it was bined , but it came from a drizzled image and still was big . It’s a Mac M1 max , proces shouldn’t be a problem , it was I had everything to high, curiosity killed the cat

The thing is I’m trying to find out if there is any sense in shooting dithering all shots ( that’s ok for noise reduction in stacking) , ( qhy 183c ) then drizzle x 2 , and then bin , I have no idea , for some reason I have in my head that this would be better for colour because I have the same information on more R and B pixels , but of course that is mi me just “ thinking “ and based on no science at all ..
So that lead in to playing with all the buttons to see what was in there …
So sorry …

James

[hixx]

Hi James,
I would not consider the drizzle - bin combo a good strategy. This is almost never lossles as You are starting off a 16-bit file hence might introduce artefacts. Drizzle will increase noise, which needs to be reduced by binning again. The gain in SNR by binning is never the amount it should have on paper

I usually stack a few hundred files exposed 30s -60s each which allows for a decent SNR. I usually dither during capturing to fight pattern noise but do not Bin (My scope/Cam combo has around 2 arcsec / pixel resolution.
I also have an M1 max and it's much faster than the previous i7 I had before, but as You I am waiting some minutes on final HDR rendering. I either set a preview by drag & pull or I reduce Context Size to 25-30. This should respond within seconds. For larger scale detail, I just use the preview on Low quality. Once I'm OK with the result, I'll increase Quality and Context size a bit (around 50 pixel) and get a cup of coffee to wait for the final result. Similar strategy in SVDecon. Just keep on clicking. SVD continuosly re-renders with each star selection.

cheers,
Jochen

[Jamesmd]

Thanks , I’ll stick to dithering, but I’ll forget about drizzle , to large files , and it complicates everything .

I’ll keep things simple at the beginning.

Thanks .

James