PixInsight Star Reduction via Midtones adjustments and Blending (by B. Blanshan)

[@lukomatico]

Thank you so much for covering this Adam! :-) It was genuinely interesting to see this broken down from a new perspective and with a much better technical understanding than my own. Thank you so much for taking the time to create and share this, and a huge thanks for the shout-out too! All the very best, Luke

[@AdamBlock]

Thanks Luke. I am waiting on a blessing of some sort (I hope) from Bill.

[@anotherastrochannel2173]

Wow, very well done explaining these processes Adam, and thank you for sharing this with your viewers! I really do hope these processes help and I sincerely hope they evolve into something even better. Regards, Bill

[@JethroXP]

I saw this a few weeks ago on lukomatico's channel and was so thoroughly impressed. It's such an elegant, simple, and fast solution. Thanks for bringing even greater attention to Bill's work, he's made a great contribution to the community.

[@AdamBlock]

Glad you like it!

[@davecurtis8833]

Very interesting. Enjoyed the deep dive into the math.

[@AdamBlock]

Glad you enjoyed it!

[@joebiscoeiv747]

Love this. I’ve used Bills expressions as well. Very simple and effective. I’m making my way through your PixInsight fundamentals course and have really begun to see just how powerful Pixel Math is. Great tool! Great video!

[@AdamBlock]

Awesome! Thank you!

[@briansnell9179]

Thank you for sharing this Adam, a great additional tool for Pixinsight. As usual a good video and impeccably explained.

[@AdamBlock]

thank you.

[@richardheinsohn2624]

Adam, this was a great video breaking down Bill's equations of how these processes work. Between your video and Bill's, I have a better understanding of the process and how it's used in star reduction. I will be adding them to my stable of image processing.😀

[@AdamBlock]

Thank you.

[@smboelaars]

This is fantastic. Thanks for your in-depth explanation and demonstration, Adam "Deemphasized" Block. ;-) It's really helping demystify pixelmath.

[@AdamBlock]

Thanks for checking out the video.

[@darkskygeek]

Brilliantly simple and oh so well explained! Thank you so much!

[@AdamBlock]

Glad you enjoyed it!

[@Tronfi]

This is fantastic Adam. Congrats.

[@AdamBlock]

Thank you!

[@tlengwall]

I just started using Blanshan's method of star reduction and I like it very much and I really appreciate your explanation of it. I now feel that I understand how it really works. Thanks so much for doing this.

[@AdamBlock]

Thank you the feedback!

[@astroimagem7200]

Thanks to you , Luke and Bill ! 👏🏻👏🏻👏🏻

[@lukomatico]

I'm glad you like the tools my friend!! :-)

[@bnkohrn]

This is so good! *chef’s kiss*

[@AdamBlock]

lol

[@antipodesastro667]

Thanks Adam (and Bill). Always find your videos informative and useful 😊

[@AdamBlock]

Thanks for watching!

[@davidwood4663]

Adam - thanks for the "insight" on Bill's processes. Bill's SR methods were brought to my attention a few weeks ago. I put together a P.I. project that compared the two methods in the EZ suite and Bill's three methods using some data of the Iris nebula that I was working on at the time. In the end, I found the resulting images using your method in the EZ suite to have a slight advantage over Bill's #3 method at least using that data set.

[@AdamBlock]

It is good to hear my approach isn't completely obviated. :)

[@GaryP747]

Always enjoy & appreciate your contributions! Scripts are generally a compromise where we accept intermediate steps with no tweaking for a specific image. I like to consider image procesing with life choices. How much are you prepared to compromise? Seeing and pixel scale are also major factors in planning & processing👌🙏😍

[@TheDicsolovag]

Awesome technique! How I do reduction recently is very similar. I experimented out this on my own and haven't recognized that it is already discussed. So here is my flow: Create a luminance image and stretch it quickly with STF and Histogram transformation. Then run a starnet2 and get the starmask as well. Apply the inverse of the starmask to the original image thus target everything else except the stars. Then run a starnet2 again. This way starnet will try to remove the stars but it can only allowed to do gradually by the starmask applied.

[@AdamBlock]

I will need to try this. This actually is somewhat of a variation of my method (since the results of starnet2 are just being put into the outer parts of the stars based on how protective the mask is).

[@DM-oj3pb]

Amazing tutorial

[@AdamBlock]

Thank you!

[@andreascordt4821]

Thank you for technical background and very smart demonstration. Now I understand how it works. The advantages of Bills methods are - they are very fast - there are parameters to get different results Perhaps you can add these additional function to your method, which I also loke.

[@AdamBlock]

Thanks for the feedback!

[@utahdesertremoteobservator8328]

It seems like you'd get a very similar result if not the same) by duplicating your image, darken it with histogram or curves, then run your star removal tool with the setting to create a stars-only image, now those would be reduced stars. Then combine that with the original.

[@astrophotonics9470]

Good stuff.

[@AdamBlock]

Thank you!

[@jamesgoodall3818]

Thanks Adam you're brilliant! Along with Bill's new PixelMath star reduction I'm hoping someone will incorporate into it some star-shape improvements too! Among numerous other scopes I'm using 8" and 11" HyperStar SCT scopes and the 8" + HS in particular is giving me star-shape trouble. Even after a great deal time and effort calibrating I still get corner-stars that have a bit of comet-like distortion with an APS-C ZWO 2600. I have tried to eliminate the issue including adjusting for camera sensor-tilt and also using David Ho's 'Hotech Advanced CT laser calibration tool' but still some star distortion exists - maybe it's a less than perfect HyperStar lens but I'm hoping someone can help solve this with star-shape software. I do not like the results I get with deconvolution. I'm not trying to cheat but I bet there's a bunch of folks that would appreciate this as a Pixinsight addition. I put a bug in Russell Croman's ear, I bet he could figure it out... Keep up the great work!

[@niccoc1603]

this is a nice method, however since you are creating a starless image, why don't just stretch stars separately and recombine at your taste?

[@zelodec]

At least 1 more positive thing about this year.

[@AdamBlock]

:)

[@brod5352]

Now I know why my new images have "Starless" at the end of the image file name. Why won't it work with linear images? I always have to permanently stretch the image before I can use the EZSTARREDUCTION script. I bet if I watch enough of your videos I'll find out. ;o)

[@mikei.6294]

Does this method work on both linear and non-linear images?

[@AdamBlock]

I think the most meaningful usage of this method is on non-linear images. The stretched images show the outer "fuzzy" parts of stars (PSF)- and this is the "shrinkable" part. The values would be so small in linear data...I can't imagine it would be useful and I do not know how you would decide to make it non-linear from there.

[@cemoguz2786]

I like astro comunity