Photoshop Calculations = Math, right?

This is a goes post from the talented Janine Smith In my opinion the name "Calculations", in and of itself, is the biggest drawback of this really awesome tool. I think if the folks at Adobe had called the thing "Melvin" there wouldn't have been nearly the confusion over it. The name is daunting to those of us with Math Phobia, but the command itself is just nifty!

Even when I began to understand that Calculations might actually be a feature I could use in my work, I just wasn't getting it! I watched training videos, read articles, asked people to just wasn't getting through. For some reason, even the explanations were coming across as somewhat mathematical therefore they were bypassing the connection in my brain that would allow them access into the inner sanctum of my cerebral cortex. Until the day Deke McClelland was guest-blogging on Scott Kelby's blog and the clouds parted and the sun shone through!

I'll say right off the bat that Deke's tutorial was dealing with Calculations as a masking tool. I think as a tool in photo restoration, that alone can be invaluable. But then I also started looking at the other use for Calculations for me, as a restoration artist. Just what is that, exactly?

Well, literally, it is what it is! Calculations is a Channel Blender! I see three main areas, so far, in which Calculations can benefit photo restoration. Analysis, channel blending and masking. Remember, since Calculations only work in RGB mode, always scan your photos, yes, even the black and white ones, in color! Calculations aside, it should be a part of your restoration workflow, lest you severely limit your repair options!

In case you've never seen Calculations, have absolutely no idea what in the world I'm talking about, you'll find this little gem in the Image menu. Image > Calculations...and this dialog box will appear.


You'll have the ability to blend different sources, different layers (I confess, up to now I've only experimented with "Merged" layers), and any two of the Red, Blue and Green channels. You'll have the ability to invert one or both of the channels .You'll also have at your disposal all of the familiar blending modes as well as two new ones: Add and Subtract. Then you can decide whether to make your blend into a new document, selection, or a new channel.

Regarding analysis, Calculations is a great way to take a photo, for instance, that's so faded it's not immediately clear what is even in the picture, and determining it's chances of restoration. In the example, below, from my families personal collection, I could see a couple people and had a good idea one was my grandfather, but wasn't really clear about the entire composition. After filtering it through Calculations using the green and the blue filters (the red was almost totally shot), I can see it's my grandfather standing next to my grandmother, with her holding up her hand to show off her wedding ring. Since she'd probably only being doing that at the time of her wedding, not only do I now know for certain it's my grandparents in the photo, but I also know the photo was taken in 1921. My mother was also thrilled to see her father was smoking his pipe in the photo, which is how she remembers him best!


By using calculations as an analysis tool, I determined in less than five minutes that, yes, this photo could be restored, given time and a lot of patience, and that it would very much be worth it to my family.
Over the next couple of weeks, I'm going to go over the two other photo restoration worthy benefits of Calculations, channel blender and masking tool.

Janine Smith is the owner of Landailyn Research and Restoration, a Fort Worth, Texas based company whose services include family history research and photo restoration. Janine honed her skills in restoring badly damaged photos as a volunteer with Operation Photo Rescue, a non-profit organization whose mission is to repair photographs damaged by unforeseen circumstances such as house fires and natural disasters. Janine’s work is well-known in the world of genealogical and historical societies, museums, libraries, university archives, and non-profit organizations; appearing on the board of directors for several organizations and institutions. She is a sought-after lecturer on photo restoration and preservation to libraries, genealogical and historical societies.