Final touch of images in Lightroom

Yannis Doukakis

Active member
May 19, 2020
29
0
Thessaloniki, Greece
If you have latest Lightroom and a fairly powerful computer, after you do all the processing in linear space, you just do a gentle Histogram transformation (more gentle than the STF auto), protecting mainy the highlights, save the image into 32-bit float TIFF and load it in Lightroom.
There you can easily fine-tune White balance (to make it aesthetically more pleasing), adjust Highlights and Shadows.
The "texture" value makes the stars a little bit more prominent.
The Vibrance and a little bit the Saturation can help eliminate the desaturating effects of LRGB
You can use color profiles (see Modern 07 - gives contrast and colours a punch)
Noise Reduction should be done in PixInsight - NR of LR is too damaging for galaxy cores, stars.
Usually you have to start by increasing Exposure to 1-2 stops at least.
The advantages are that all the above are non-destructive so it is easy to "play" with them.
I may sound heretic in PixInsight forum, but what I would like to share is that 32-bit float TIFF is a nice format in case you want to share data with Lightroom. In Photoshop, you have to turn on, Preferences->File Handling->Use ACR to convert 32 to 16 bit and then load the float image and switch the image mode to 16 bit.
 

Juan Conejero

PTeam Member
Sep 2, 2004
7,402
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Valencia, Spain
pixinsight.com
Hi Yannis,

We regard all of the things that you have described above as painting and retouching magic tricks without any value for image processing. We strongly discourage our users from damaging their valued data that way. The Universe does not deserve that.
 
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Yannis Doukakis

Active member
May 19, 2020
29
0
Thessaloniki, Greece
We regard all of the things that you have described above as painting and retouching magic tricks without any value for image processing. We strongly discourage our users from damaging their valued data that way.
Sorry Juan Conejero, but your answer is almost rude. You create a software but you have no right to judge what the users who paid for this software do with it. This shortsightedness, trust me I make software for 30 years now, does not help in the design of future versions.
As I understand from both of the above comments all discussion on imports and especially exports is forbidden in this forum, as any mention to other software is a no-no.
However your Manual says that no other software can read float TIFF. I explained that this indeed is a way to transfer images to another software with little loss. If someone does not want to enhance the image outside Pixinsight software, fine. His choice. But he may want to print the image with high end inkjet printers and use special papers with their own color profiles.
Finally I would really like to see where is the borderline of scientific work and magic tricks without any value. How ”scientific” are masks to do local enhancing of images, or visual stretching?
 

Juan Conejero

PTeam Member
Sep 2, 2004
7,402
67
56
Valencia, Spain
pixinsight.com
Hi Yannis,

Please don't take my post as an offense or something like that; that wasn't my intention. I am not judging what you do, but just stating my opinion about important topics on PixInsight Forum. I've been writing code for nearly 40 years. Yes, I'm a bit older than most people here, and yes, I was a geek when I was young :)

I'll try to explain why I have reacted as I've done, as well as my personal opinions about some key topics that you have touched (directly or indirectly) in your post:

- This is PixInsight Forum, where talking about other competing software applications is not allowed in general. See the forum rules. Naturally, there can be exceptions, but only when the topics discussed can be of interest for PixInsight users, mainly to help them in using PixInsight. Other applications don't sponsor us, as you surely can figure out.

- The tasks you have enumerated don't inform about anything you can't do with PixInsight. White balancing and brightness/contrast modification can be done with a variety tools in PI. For example, we have the PhotometricColorCalibration tool, which computes white balancing factors for linear images based on astrometric solutions and photometry. To make stars more prominent you can also use many tools in PixInsight (although I personally disagree with this concept). We have very powerful tools to control color saturation. PixInsight is a fully color managed application where you can of course use color profiles, and our color management engine has nothing to envy other implementations (it's probably the other way around in most cases). Finally, everything is non-destructive in PixInsight because you have absolute control on the processing histories of all images, with unlimited undo/redo levels and sophisticated history management features.

- As for printing images, I have to agree: we still haven't a good implementation, especially on macOS and Windows. I hope to overcome this limitation in a future version, but there are many high priority tasks before investing time in that.

- Compared to the rigorous, efficient and soundly-founded implementations that we have in PixInsight, other painting and retouching applications are very inferior when used for astrophotography. See FAQ 1.11 for our official position about using these applications in astrophotography.

- I am not talking about science. Masks have nothing to do with science, but they have a lot to do with our concept of astrophotography. A mask should be designed and applied homogeneously to the whole image, and normally it should be based either on properties of the photographed objects, or on properties of the image considered as a data structure. For example, a mask based on brightness evaluated uniformly on the entire image can be valid, but a mask painted to process the core of a galaxy selectively is a conceptual error. A mask to protect stars can be valid because stars can be regarded as singularities where some algorithms are not applicable. The differences can be subtle and of course there are gray zones, but this is a fundamental topic that separates documentary image processing from arbitrary manipulations.

As you see at this point, PixInsight is not just a software application. We grew up in the world of astrophotography, and are deeply involved with this discipline.
 

Yannis Doukakis

Active member
May 19, 2020
29
0
Thessaloniki, Greece
Hi Juan,
Thanks a lot for your answer, it clears a lot of misunderstandings.
I would like also to mention that I never meant to compare PixInsight to other software. My intention was to describe how to transfer images processed by PI to other software without quality loss, not to do a side by side comparison, as this would be a comparison of apples to oranges.
You beat me by a few years in writing code. As I have mentioned in a private e-mail I sent to your support for some improvements on macOS, I have exactly the same position as you have in your company, just in a different industry (embroidery software). Even if I got upset with your initial answer, I have to admit that I am not that different when it comes to my software. All of us treat our software as our children and get offended easily.
In any case keep up the good work. The quality of the algorithms in this software is incredible. They need some polishing on the UI / Documentation side, but you can see it in the results.