auto levels based on a selection apply to whole image

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Hello,

I have a large number of scans of black and white negatives and need to apply a quick correction to each of them. A custom settings Auto Levels works well but the setting has to be determined by drawing a marquee area of interest within the film frame. I can then undo, deselect, and reapply the last used Levels command to the whole image. That works one by one, but I need to do this with 1,000s of images in an automated way. The negatives are all different so the setting for each has to be determined one by one. What I would like is to apply the levels adjustment determined by a selected area to the whole image, not just within the selection. Is there a way to do this? That can be recorded into an action?

Thanks in advance for any tips.

David
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David Remington

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Posted 4 weeks ago

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Todd Shaner, Champion

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Create a New Action:
Start Recording
1) New Adjustment Layer Levels
2) Apply Auto Levels with your desired settings
3) Select All
4) Fill Contents White
5) Flatten Image
Stop recording
Open a scan image file, select the area of interest, and apply the above action.
(Edited)
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David Remington

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Hi Todd,

Perfect! Thanks fo this tip. The negatives are all 2 1/4 cropped about the same so I was able to record the area of interest selection at the beginning of the action you outlined. Also a desaturation step as these are color scans of B&W negtatives and have a cast.

Thanks again.

David
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Todd Shaner, Champion

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Glad that helped. Just so we're on the same page here are the steps needed in the action with the added steps.

1) Select the area of interest with the Selection tool
2) Image> Crop
3) Image> Mode> Grayscale (RGB not needed and reduces file size)
4) Image> Adjust> Levels> Auto (with the desired settings)
5) Select> Deselect (CTRL + D)

Mark Segal and I did an article on Luminous Landscape titled Scannerless Digital Capture that may be of interest.

https://luminous-landscape.com/scannerless-digital-capture-and-processing-of-negative-film-photograp...

The companion PDF provides more details and on pg. 31 Mark discusses processing camera captured B&W negative film images.

https://luminous-landscape.com/articleImages/CameraScanning.pdf
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David Remington

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Hi Todd,

I do not want to crop the negatives. I'm leaving them framed as they are with the edges of the film (and more) showing. They are all framed pretty much the same so I can use the selection to define the area of interest for the auto levels. My Action starts with the selection then uses your original steps. I may save them as grayscale. The originals were color but there is no significant color information. This is an acquired collection of images. We have been using digital cameras with a light box for black and white negative and color positive capture for years now ourselves. Color negatives are still tricky. I don't suppose you have a good process for removing the orange mask? We've tried several methods and it never looks quite right.

Thanks again for your help.

David
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Todd Shaner, Champion

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Sorry, forgot about the actual usage of the selection area.
Color negatives are still tricky. I don't suppose you have a good process for removing the orange mask? We've tried several methods and it never looks quite right.
The article at the links provided discuss two workflows for processing color negative film images captured with a camera copier setup. Mark Segal uses MakeTiff to convert the raw file and SilverFast HDR for processing. I use Lightroom/ACR and Photoshop. Since writing the article I've added some additional steps for improving the orange mask removal using LR/ACR.

You can download a Dropbox folder I created with the original article, companion PDF, and an additional PDF with the improved mask removal process. A PS Action for processing color negative film images and an Excel spreadsheet with settings for numerous film types is also in the folder.

https://www.dropbox.com/sh/u5pnzbesvqen1hv/AABZyaWAn33jCwEinkT45iFAa?dl=0

Some people have had success using the new LUT based camera profile format. But it requires creating a separate camera profile for each color negative film type and if the film samples have "aged" differently it doesn't work well. In addition all of the Develop controls work backwards due to a lack of an "invert" function inside LR/ACR. It's been requested and you can add your Me To vote and  Follow here:

https://feedback.photoshop.com/photoshop_family/topics/inverting_in_camera_b_w_negative_scans_to_pos...

My LR/PS Action workflow is film type independent since it uses Auto Curves for color correction. Color corrections required after running the action can be made by making small adjustments to the RGB curve end points to remove any WB differences between shadows, midtones, and highlights. This is normally only required with older film that hasn't aged well. I've gotten good results with Kodacolor X and II film from the early 1970s (~50 years old), which have noticeable color shift in the orange mask.
Let me know if you have any questions, which I'm sure you will.