How to auto-align channels

[ultrachrome]

I have a client that sent me in a really lovely 5 x 7 glass plate color seperation negatives of the female lead of "It's a Wonderful Life" Donna Reed - some perfect Christmas work to be doing! I've manage to scan the three negatives and get those scans into the appropriate color channels. I've painstakingly done my best to align these using the catchlights in her eyes. Right now the face looks pretty good but if I look at the edges of the image, the alignment doesn't seem quite perfect. Is there a way to have Phososhop auto align these? Alternately, is there a way to move where the center of the rotation is when I'm in transform the way you can do with "crop". That way I could put the center of rotation on a catchlight and then move to the edge of the image to rotate until things line up perfectly.

[Chuck Uebele · Accepted solution]

You can't align them in channels. I would put them all as separate layers, align them, then apply them to the channels, using apply image or copy and paste.

If there are just 3 plates for RGB, then you can also put them into the layers, change their blend mode to linear light (add), then add corresponding solid fill layers for each color, set to lighten blend mode and clipped to the respective layers. That way you can see the result in color.

[ultrachrome]

Thanks Chuck! Sounds like a great idea and I did as you said and now have each of the colors as layers and used the auto align to get them lined up. I've never used "apply image" before and I'm not entirely sure what it does. When I go to apply image, it's grayed out. There are other ways I could deal with this now that the layers are aligned to get them into the appropraite channels but I'm curious about the "apply image" now.

[Chuck Uebele]

You can just copy and paste each layer, if that's easier.

[Chuck Uebele]

To use apply image, you would select the channel that you want to fill with a layer. The select apply image, it shouldn't be grayed out at that point. Then in the dropdown menu, select the layer you want to use, and select normal blend mode.

[ultrachrome]

Thank you...I got it all sorted using your advice. Looks great now!

[Bojan Živković]

There is auto-align function from Edit > Auto-Align Layers which work with layers.

When transforming you can move the center reference point anywhere you want. If you do not see reference point when transforming then click inside Toggle reference point which is in the options bar.

[ultrachrome]

Excellent! Really nice to know how to engage the center point. Thanks!

[ultrachrome]

I got permission from the client to post this image reduced and with a watermark. Chuck Uebele's technique was used to align the layers. I had though I had it pretty good doing it manually but this is definitly better. Thanks again Chuck!

[Chuck Uebele]

Very nice!

[ultrachrome]

Thank you! I'm trying to understand what gives this a unique retro color look. I wonder if the same color character would occur if you replaced the film with digital sensors.

If you're interested, here's the negs in the scanner...

[Chuck Uebele]

I'm not sure. Different films have/had different spectral sensitivity, so there most likely would be some difference, but it would be interesting to see.

[Semaphoric]

Here's an article about the sort of camera likely used to take the photo: http://www.vintagephoto.tv/bermpohl_img.shtml

[Chuck Uebele]

I always wanted to play with that type of camera.

[ultrachrome]

I did a bit of research and found out this photo was taken by Harry Warnecke and/or Gus Schoenbachler. Apperently they built their own camera systems but this one you link to here is just lovely. These were 5x7 glass plates. I consider myself fortunate to get this job in.

https://npg.si.edu/exhibit/exhwarnecke.html

[Chuck Uebele]

Nice!