Workflow and Image quality troubleshooting

Questions and answers about processing in StarTools and how to accomplish certain tasks.
alinderbaum1
Posts: 11
Joined: Mon Mar 30, 2020 8:31 pm

Re: Workflow and Image quality troubleshooting

Post by alinderbaum1 »

Ivo,

My understanding is that calibrating means that you stacked with darks and flats. What do you mean when you say "data in your stacks (in the form of light frames) is not necessarily bad, it just doesn't seem like it is calibrate"?

Going back to an initial item, I am following your tutorial (https://www.youtube.com/watch?v=IDY3ov2 ... e=youtu.be) from the StarTools website on M42. I am following it as step-by-step as I can. I also cranked up the Aggressiveness as you suggested. What I am not able to figure out is why after WIPE (which my image is not even close to your wiped image) and selecting KEEP, my image returns to the initial uploaded image and never changes after any of the remaining modules (link below)? This happens each time regardless of which tutorial I am following on Startools.

Link - - https://1drv.ms/u/s!At7UzxGKX97o7kvVGS6 ... P?e=Nwx4Aq
These are using the same data set you used (lights only).

TO make things simpler for you, how can I put an image in the body of this message without having to use OneDrive or a separate file attachment?

Many thanks.
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Re: Workflow and Image quality troubleshooting

Post by admin »

alinderbaum1 wrote:My understanding is that calibrating means that you stacked with darks and flats.
Correct!
What do you mean when you say "data in your stacks (in the form of light frames) is not necessarily bad, it just doesn't seem like it is calibrate"?
Apologies. That should have read "the data in your stacks (in the form of light frames) is not necessarily bad, it just doesn't seem like it is being calibrated". E.g. the stack you uploaded last (which I processed) contains ok data. It is just marred by - so far - not being able to calibrate it properly with flats. E.g. there is potential!
Going back to an initial item, I am following your tutorial (https://www.youtube.com/watch?v=IDY3ov2 ... e=youtu.be) from the StarTools website on M42. I am following it as step-by-step as I can. I also cranked up the Aggressiveness as you suggested. What I am not able to figure out is why after WIPE (which my image is not even close to your wiped image) and selecting KEEP, my image returns to the initial uploaded image and never changes after any of the remaining modules (link below)? This happens each time regardless of which tutorial I am following on Startools.
This behaviour has changed slightly since 1.5 (e.g. tutorials older than 1.5 will see Wipe behave differently). Rest assured that the dataset is definitely being cleaned, however this is all done in the linear domain and the stretched version you see is only a temporary stretch of the linear data. Afterwards, you will have to redo your stretch (as seen in all tutorials and workflows). This was also always true in versions prior to 1.5, but these versions would try to reconstruct the previous stretch (which was really quite useless, as gradient removal will almost always mean the previous stretch is no longer desirable or optimal). For a full explanation of what is going on and why you need to redo your stretch, see also here.[/quote]
TO make things simpler for you, how can I put an image in the body of this message without having to use OneDrive or a separate file attachment?
Make sure your image is a JPEG and not too big (max, 500KB - if it helps, StarTools will save JPEGs by changing the .tiff extension into .jpg when saving), then under the "Upload attachment" tab, click Browse, find your JPEG and click Add the file. You can now click 'Place inline' to place the image in your post.
Hope this helps!
Ivo Jager
StarTools creator and astronomy enthusiast
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