P: Ability to invert negative scans to positives (color and black-and-white)

So very disappointed that another update (Lr Classic 8.4) comes along with no sign of any implementation of a negative/invert setting that will allow users to process DSLR scanned negatives with ALL controls functioning normally.

Options de développement de négatifs

Anthony, anyone at Adobe trying to read (top-down) through the numerous conflicting and redundant comments in the replies here will more than likely ignore the request. It's unfortunate and I plead guilty to getting into the fray myself!

Towards correcting this I have just sent an email directly to Adobe staff providing specific details why an LR/ACR raw data invert function is needed and the benefits. Hopefully it will make it up the Adobe totem pole and we will at least get a reply here. Stay tuned!

We are still waiting for a proper implementation of a Negative function in Lightroom Classic. This topic has had a lot of discussion and many users have requested it, but Abode continues to ignore it. Yet, in the last update we get a Texture adjustment and Flat Field Correction (which was previously a plugin and migrated into the core code). These are both welcome and useful new features, but a negative function has been requested for 7 years now and still nothing.

A search of this forum reveals only two requests for 'skin smoothing', which is as close as I can get to the Texture adjustment. One of these was 8 years ago with 2 Me Too's and 3 Followers, the other was 5 years ago with 1 Me Too and 2 Followers, yet we get a Texture adjustment.

So the Me Too's and Followers don't seem to count for anything. This Negative function request has 48 Me Too's and 43 Followers, and I imagine that there would be a lot more users out there who would appreciate this functionality, but haven't participated in the discussion. I also would imagine a Negative function to be far easier to implement than the Texture adjustment.

So how about it Adobe and the Lr development team? How long do we have to wait?

I have DSLR 'scanned' around a hundred 100-year-old glass plates for our local historical society using a 'Negative' profile that I created, but with all the tone controls reversed and some not working properly at all, a proper Negative function would make life so much simpler. A colour cast removal tool would also be essential for DSLR 'scanned' colour film.

I would be one more user needing a proper way to invert negative images in LR Classic (either by custom camera profile or plugin like Negative Lab Pro). It would be straightforward if Camera Profile (with negative curve in it, in LR 7.3 and later) would be applied before any other adjustments, not after.
One more drawback of current behaviour when using inverted camera profile or tone curve is that face recognition and tagging doesn't work on negative images.

There are actually two issues with LR that prevent it from properly processing camera raw color negative film image files.

1) Lack of a true Invert function that inverts the raw data BEFORE any of the controls are applied.
You can use and inverted LR Tone Curve and get used to using the controls backwards.
A better option suggested by *John R. Ellis is to use Edit in PS and then invert it in PS and save back as a TIFF. When doing this it works much better if you first adjust the LR WB using a custom camera profile as outlined below. You can temporarily invert the Tone Curve (create a preset to save it) and then follow the below instructions to set the WB. When the WB is properly set make sure to return the Tone Curve to its normal 'Linear setting before using Edit in PS.

2) Insufficient WB Temperature control range, which is currently limited to 2000.
The orange mask in many color negative film emulsions is lower than this setting. Further, the Adobe camera profiles are dual-illuminant (6,500K + 2850K). Whenthe Lightroom WB Temp setting is below ~4,000 the 2,850 (Tungsten) table isused for color correction, which does not work well with most color negatives.
Fortunately The Adobe DNG Profile Editor (DPE) can be used to extend the camera profile's Temp and Tint ranges for use with color negative film camera raw files (i.e. captured using a camera). I suggest creating four versions of the Adobe Standard camera profile with Temp and Tint settings -25 +25, -50 +50, -75 +75,and -100 +100. You'll need to export one of the camera raw files to DNG file format with it set to Adobe Standard profile. Open the DNG in DPE and in the Color Matrices tab change the Temp and Tint settings and then go to File>Export and rename the profile so you can identify it by filename. Example: 5D MKII Adobe Standard WB -25 +25. Then process the remaining three settings the same way. Save them to them below folder location and when done restart LR to load the new profiles. You'll need to do this for each camera model you use to capture the color negative film images.
Windows—C: \ Users \ [your username] \ AppData \ Roaming \ Adobe \ CameraRaw \ CameraProfiles \

Mac—Macintosh HD / Users / [your username] / Library / Application Support / Adobe / CameraRaw / CameraProfiles /

Use the Custom WB Camera Profile that requires a WBTemp setting no lower than 5,000 to correct the WB. You may also want to create and try custom WB camera profiles using one of the lower contrastprofiles such as Adobe neutral and the higher contrast and color saturation Adobe Color. They all are based on the same Adobe Standard profile, but with different contrast and color saturation, which may be helpful.

Thanks, Kevin.  I've only been doing b&w, so I'm sure the experience is very different working with color inversions.  

The problem with inverting in Photoshop comes in when dealing with raw files. Raw is critical for dealing with color negatives—particularly older ones where the color has shifted, or they were originally exposed poorly. My go-to process for shooting transparencies is to bracket three exposures in-camera, and then combine those raw files in Lightroom. This is impossible for color negatives, of which I have BOXES full. With an easy "Invert" button, it would save those negatives.

The problem with inverting in Photoshop comes in when dealing with raw files. Raw is critical for dealing with color negatives—particularly older ones where the color has shifted, or they were originally exposed poorly. My go-to process for shooting transparencies is to bracket three exposures in-camera, and then combine those raw files in Lightroom. This is impossible for color negatives, of which I have BOXES full. With and easy "Invert" button, it would save those negatives.

Hi Risto, 
I don't think your images should be degraded at all by inverting them outside Lightroom.  If you're using something like Photoshop, I don't think it would be degraded at all, unless it's being saved as a low-quality JPG.  Perhaps some other programs would degrade an image in ways I don't understand.  By the way - I'm not trying to argue with you at all, just trying to help.