Color pictures from B&W vs. Color film

[cotdt]

With the cost of 4x5 color film over $2 per sheet these days, and with the even more expensive cost to develop, I'm looking at $5 a photo or more. B&W film is only $0.40 a sheet and development is virtually free (pennies at most).

By taking a set three B&W pictures, one with red filter, then green filter, then blue filter, and merging the colors together in Photoshop will give the color picture, and be much cheaper than using color film. Has anybody had experience with this method and its effectiveness?

Reference:
http://photo-utopia.blogspot.com/200...om-b-film.html

[Peter K]

This was the method for color photography up to 1935 Kodachrome was invented. Also special cameras with a beam-splitter where aviable. And quick change backs for three exposures.

Try it with the Kodak Wratten filters 29 deep red, 61 dark green and 47B dark blue and panchromatic film. But the problem is registering the three images. One needs a realy good tripod, a sturdy camera and realy flat film.

BTW the Technicolor movie camera was also equipped with a beam-splitter and three strips rawstock up to the fifties.

[Brian Ellis]

I'm far from being a Photoshop expert but as you probably know, Photoshop has its own red, green, and blue filters. If using "real" filters would work as Peter suggests, maybe using Photoshop's filters would work as well and you'd avoid the registration problem since you'd be working on only a single image duped three times.

[D. Bryant]

maybe using Photoshop's filters would work as well and you'd avoid the registration problem since you'd be working on only a single image duped three times.

Say what?

Don Bryant

[Nathan Potter]

Say Brian, I don't quite follow you here. I guess the workfow would be as follows.

One would still have three original negatives taken with three different filters. These would have to be individually scanned then loaded into PS then combined through the PS appropriate filters and registered using PS. I'm not really adept at PS yet but it seems this could be done for an original static image (where the three original negs. are spacially exactly identical). The characteristics of the original color separation filters would need to be reproduced pretty exactly in PS in order to reproduce the original scene color characteristics. Whew! A lot of effort. Interesting though.

Nate Potter

[Daniel_Buck]

I'm far from being a Photoshop expert but as you probably know, Photoshop has its own red, green, and blue filters. If using "real" filters would work as Peter suggests, maybe using Photoshop's filters would work as well and you'd avoid the registration problem since you'd be working on only a single image duped three times.

that won't work, since your data has already been captured in B&W, you need to filter before your light hits the film. for color film, the filters will work in photoshop, because photoshop already has different info for the RGB, not so in a B&W shot. You would need to filter R G and B on seperate pieces of B&W film then combine them.

[PaulRicciardi]

I'm not too sure you could take a single BW image and make it colour in PS. I've been sitting here in CS2 for the past hour trying to do it. Here's what I have tried.

Starting with a BW image I duplicated it three times, making each new layer R, G, B. Then colorized each one accordingly and dropped opacity to 33%. Also tried to messing with the blending modes but that didn't help. The idea was to replicate a CMYK screen print but that didn't work.

I then tried it again with CMYK. Once again no luck.

Next attempt was to create three copies of the original layer, once again RGB, and then go to the channel mixer for each one and adjust the outputs for each layer. For example on the R layer I jacked up the R channel and lowered the GB channels. Did the same thing for GB channels. Then went to channels and merged channels. Nothing.

I tried the last thing again but instead of working in colour I worked in BW. Once again, three layers-RGB, channel mixer, played with channels in monochrome and then merged channels for the 3 layers. Nothing.

Maybe I am doing something wrong. I think I have the right idea...you can replicate BW filters in PS so it would serve to reason that you could replicate RGB filters on three images and then merge them together like in the original link.

My PS skills generally aren't used for this sort of thing...PS is mostly a final minor touch up for me, curves, levels that's about it so perhaps someone with more skills could figure this one out. Im curious.

[PaulRicciardi]

that won't work, since your data has already been captured in B&W, you need to filter before your light hits the film. for color film, the filters will work in photoshop, because photoshop already has different info for the RGB, not so in a B&W shot. You would need to filter R G and B on seperate pieces of B&W film then combine them.

That's what I was thinking...well there we go!

[Peter K]

One has to take three b&w negs, one with a blue filter, the second with the green and the third with the red filter. After processing and scanning the blue neg is inverted and colorized yellow, the green-filter neg will be magenta and the red-filter cyan. Than you have to combine the three images.

To try it without a camera, open a color image in PS, copy each channel, red green and blue, as three new b&w images, colorize this images as mentioned above and combine this images as a forth new image.

[Geert]

Have a look at "Le blog de la Trichromie": http://trichromie.free.fr/trichromie/

Henri Gaud is a specialist on the subject.

G