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Messages - dld

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If I remember, the Fireworks Galaxy is bright in infrared. Thus the PCC result might be more reasonable. This is one of the advantages of PCC over using the whole galaxy as white reference.

General / Re: DSLR - Cosmetic Correction and Dithering
« on: 2019 July 30 23:42:05 »
Hello, I have the 6D too and I don't do cosmetic correction. Dithering deals well with any hot/cold/stuck pixels and helps a lot with fixed-pattern noise.

(edited after Andres' comment)

You may take a look at the benchmark results users have submitted so far

However, details on swap files configuration aren't always available.

Hello StarNet fans,

If you haven't noticed it, the StarNet module seems to respect masks! Useful when you do want those tiny galaxies in your images!

I thought that you just stretch the image, remove stars and then 'destretch' result back into its original form. Then, assuming that all the nebulosity is dim, you would get good image.

Hello Nikita, this is a great point!

For a starless region and an invertible MTF, the InverseMTF of MTF(starless) should return starless ;) Thus we can subtract the InverseMTF(starless) from the linear image and obtain the stars. No need to complicate things and trying to solve a more difficult mathematical problem!

I'll have to find some time to work on this. In the meantime, any input is always welcome!

- I see that only nonlinear (stretched) images can be processed. Is this an unavoidable limitation of the implemented algorithms, or just the result of lack of network training? The ability to work with linear images would be a very important feature of this process (example: deconvolution). If this is an algorithmic limitation I can devise some ways to circumvent it, which would be relatively easy to implement.

For a reasonable invertible stretch function, and assuming StarNet preserves the bit depth of its input, maybe something can be done :)

I'll experiment on this later today ;)


After stretching a linear grayscale image using a simple MTF function, splitting into stars/background using StarNet, applying the inverse MTF separately at stars and background image, and then adding the result together, I noticed a loss in highlights. The most probable reasons for this are:  It is not easy to find non-trivial functions f for which f(x) + f(y) = f(x+y) (think f being the inverse MTF and x,y the stretched background and stars respectively). My lack of knowledge on imaging processing fundamentals (albeit the documentation on HistogramTransformation was very helpful).

I'll end this here since it's the wrong place for this, and I'll patiently wait for your thoughts on the subject.

Hello Nikita,

I did some experiments with the command line tool and now with the module. It works well with my widefield images. The equation image = starless + stars seems to hold, and can be exploited to separate and treat stars and nebulosity differently. For that reason, I believe StarNet is a solution to the nebula/stars dynamic range problem and not for creating starless images :cheesy:

Thank you for this great tool!

Image Processing Challenges / Re: Help with M13
« on: 2019 May 31 12:31:48 »
Hello and welcome!

Have a look at the "PixInsight Fundamentals" video from Adam Block;

There you will find some great tips on using DBE and symmetries to reduce those nasty vignetting rings!


Can you upload your image somewhere (Dropbox, Google Drive, etc)? Also can you provide some more info like the approximate coordinates of the image center and the arcsecs per pixel value?

Hello Rogelio,

Regarding your first question, take a look at Global Preferences > Main Window /Startup. Keep "Expand favorites item at startup" and uncheck the undesired options.


I am on a 13 inch Win10 laptop with a resolution of 3200 x 1800. PI works fine. I have set the UI scaling factor to 2.00 (Preferences > Core UI Resources > (restart PI)) to ease my eyes. Any problems I have met so far are caused by problematic graphic drivers. Unfortunately even native Win10 apps doesn't scale properly, e.g., the Device Manager.

Hello Allen,

Weights should have positive values; try to revise the weighting function you are using.

Cheers and happy weighing  :laugh:

General / Re: Price
« on: 2019 March 19 01:02:51 »
Is is that simple for you? Simple for me would be someone who runs a company and helps other people like star tools does for those who can't afford it. This old paradigm of money first people second is dying hard. I look forward to watching it die. Apparently the owner of the company is one of the cheapest people on earth as EVERYTHING goes on sale EXCEPT PIXINSIGHT. So him and his software must be brought down. I am happy it was hacked.  I laughed all day that day. This is principale for me. I would never give a company that is run cutthroat like this a dime of my money ever. Shame as it is good software.

I wish never someone visits your business saying that your work deserves to be ruined.

PI offers a generous trial period, its philosophy is clearly described at the FAQ, and there are plenty of resources out there demonstrating its workings and help a potential customer to decide.

There are many alternatives available, even offered as free software. Since you can recognize a good software I suggest you to volunteer in such projects and see how it is done.

General / Re: "Pure RAW" or "Demosaiced RGB"?
« on: 2019 March 11 03:59:46 »
No worries, PI is as vast as a basement workshop with plenty of tools ;D

I don't use the BatchPreprocessing script so I might be wrong, but I think with "Pure RAW" you have to tick the "CFA Images" when working with DSLRs or other cameras with a Bayer matrix.

I am sorry, I wasn't aware that you're using the BatchPreprocessing script; hopefully someone more experienced will clarify this!

General / Re: "Pure RAW" or "Demosaiced RGB"?
« on: 2019 March 11 02:40:20 »
With the "Demosaiced RGB" setting PI will do the demosaicing behind the scenes (and for your calibration files too!). Demosaicing = interpolation and interpolation on darks and bias is not a good practice. Calibration with debayered data is also not a good practice. Furthermore, you'll have to work with larger files. By design PI is bayer-agnostic for calibration. You only need to debayer before registration.

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