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Nnnnope. Don't understand Auto Dev in StarTools at all.


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I've been using StarTools for a while now.

At first I tried to use it 'properly' after following the tutorials, starting with Auto Dev. I sort of got it to work, but I've just decided - I really don't understand it.

I've been bypassing it and just using the manual Develop option, but I feel I should really understand what I'm doing wrong, if anything.

Whenever I use Auto Dev, I just get a horrible, overexposed mess, no matter if I select a ROI or not. I understand that it's supposed to show me the errors in my image, but it's unusable. I've noticed that if I then use Wipe, it gets even worse - but then, when I click 'Keep' after the wipe, it goes back to how it looked when I opened it, before the Auto Dev!

It's completely counterintuitive. There's no progression from 'bad' image to 'good', and frankly I don't get it. 

Does anyone else use StartTools, who can shed some light on this?

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You then redo autodev after wipe  , first autodev high lights any artifacts , then crop the border using crop, this usually  caused by stacking overlaps of multiple images so crop that out , then bin if image is high resolution, then wipe then redo global stretch using  Autodev or Dev , ivo aka @jager945 will explain more clearly.

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  • Cornelius Varley changed the title to Nnnnope. Don't understand Auto Dev in StarTools at all.

Generally the work flow is left to right in modules you just need to remember the general work flow to start off , most software isn’t intuitive without researching and reading tbh but compared to other Astro programs a bit easier than some to understand , Startools website has plenty of info on modules , and on Startools forum there is a post buy Guy on the modules and uses https://forum.startools.org/viewforum.php?f=12

ivo will respond to any questions either on here or through the forum .

 

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Hi,

I replied on the StarTools forum, but thought I'd post the answere here as well;
 

Quote

 

I've been using StarTools for a while now.

At first I tried to use it 'properly' after following tutorials, starting with Auto Dev. I sort of got it to work, but I've just decided - I really don't understand it.

I've been bypassing it and just using the manual Develop option, but I feel I should really understand what I'm doing wrong, if anything.

Whenever I use Auto Dev, I just get a horrible, overexposed mess, no matter if I select a ROI or not. I understand that it's supposed to show me the errors in my image, but it's unusable. I've noticed that if I then use Wipe, it gets even worse - but then, when I click 'Keep' after the wipe, it goes back to how it looked when I opened it, before the Auto Dev!

 

This is a separate thing and doesn't have much to do with AutoDev. Wipe operates on the linear data. It uses an exaggerated AutoDev (e.g. completely ignoring your old stretch) stretch of the linear data to help you visualise any remaining issues. After running Wipe, you will need to re-stretch your dataset. That is because the previous stretch is pretty much guaranteed to be no longer be valid/desirable. That is because gradients have been removed and now no longer take up precious dynamic range. Dynamic range can now be allocated much more effectively to show detail, instead of artifacts and gradients. As a matter of fact, as of version 1.5, you are forced to re-stretch your image; when you close Wipe in 1.5+, it will revert back to the wiped, linear state, ready for re-stretch. Before 1.5 it would try to reconstruct the previous stretch, but - cool as that was - it really needs your human input again, as the visible detail will have changed dramatically.

Quote

 

It's completely counterintuitive. There's no progression from 'bad' image to 'good', and frankly I don't get it.

Can anyone shed some light on this?

 

You can actually see a progression by gradually making your RoI larger or smaller; as you make your RoI smaller you will notice the stretch being optimised for the area inside your RoI. E.g. detail inside the RoI wil become much more easy to discern. Conversely, detail outside the RoI will (probably) become less easy to discern. Changing the RoI gradually should make it clear what AutoDev is doing;

file.php?id=1480
file.php?id=1481

file.php?id=1482

file.php?id=1483
Confining the RoI progressively to the core of the galaxy, the stretch becomes more and more optimised for the core and less and less for the outer rim.
(side note, I'd probably go for something in between the second and third image :) )

E.g. AutoDev is constantly trying to detect detail inside the RoI (specifically figuring out how neighbouring pixels contrast with each other), and figure out what histogram stretch allocates dynamic range to that detail in the most optimal way. "Optimal" being, showing as much detail as possible.

TL;DR In AutoDev, you're controlling an impartial and objective detail detector, rather than a subjective and hard to control (especially in the highlights) bezier/spline curve.

Having something impartial and objective is very valuable, as it allows you to much better set up a "neutral" image that you can build on with local detail-enhancing tools in your arsenal (e.g. Sharp, HDR, Contrast, Decon, etc.);
highlightpreservestretch.gif
Notice how the over-exposed highlights do not bloat *at all*. The cores stay in their place and do not "bleed" into the neighboring pixels. This is much harder to achieve with other tools; star bloat is unfortunately still extremely common.

It should be noted that noise grain from your noise floor can be misconstrued by the detail detector as detail. Bumping up the 'Ignore Fine Detail <' parameter should counter that though.  

I hope the above helps some, but if you'd like to post a dataset you're having trouble with, perhaps we can give you some more specific advice?

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Hello Ivo, thanks for such a comprehensive reply (and I can see you posted on the StartTools forum too, I didn't know you were on here).

I'll go through what you've said and see if I make more progress with it.

:)

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I have always had issues getting decent results from Startools. Part of it is die to my data admittedly. 

I joined the Startools forum and the creator Ivo, has been most helpful in responding to my queries. 

Also following this post with interest. 

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That's one thing I've found to be the case with astro software - really great support from the creators themselves. It's the same with APT who is, by amazing coincidence, also called Ivo. :)

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I also wasn’t using the Autodev function properly but Ivo kindly took some of my data through his workflow and produced an image better than anything I had achieved to date, also providing a detailed explanation of how he got there.

Top Bloke! 👍

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Having recently taken the opportunity to process a member's data shared on this site it made seeing how modules work easier as it was so much better than my data is and without any particular flaws which my data has. Autodev with manipulation pulled all the faint dust clouds out which I couldn't get from the develop module.

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Agree with both comments.

Ivo did the same for me - went through my data, produced something better, explained what was wrong with my data and what he did with it.

Also, downloaded some pristine raw data from Jerry Lodriguss, and it all works so much better. 

So, I just need to improve my acquisition by learning from Jerry Lodriguss, and improve my processing by learning from Ivo!

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  • 4 months later...

Hi,

I'm late to to the post .. but Ive created a video with APP for the stacking and then processing in Star Tools for M31 with the exact same camera that you have.

Please let me know if the video was helpful, I'm already working on further objects and workflows via You Tube. So please subscribe to be notified as they appear !

https://www.youtube.com/watch?v=xxkDDLspaiM

 

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  • 3 weeks later...

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