Can B&W Photos Be Accurately Restored to Their Original Colors?

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Discussion Overview

The discussion revolves around the possibility of accurately restoring the original colors of black and white photographs. Participants explore the relationship between intensity in black and white images and the corresponding color ranges, as well as the implications of color perception in black and white media.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants propose that different intensities of black and white in old photos correspond to specific color ranges, suggesting a potential for conversion back to original colors.
  • Others argue that different colors do not conform to different intensities, citing practical experience with photo editing as evidence.
  • One participant shares anecdotal evidence from their father, who claims to discern colors in black and white films, raising questions about the role of prior knowledge of object colors in such perceptions.
  • Another participant references Edwin Land's technique of projecting two black-and-white images to create the appearance of color, noting the specific use of filters and questioning the implications of this demonstration.
  • There is a discussion about whether a black and white photo could represent a source with color changes and whether any intensity of black or white corresponds to multiple colors.
  • A participant explains how digital color images are represented, emphasizing the range of brightness levels for each color channel and the resulting combinations that create various colors.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between intensity in black and white images and color perception, with no consensus reached on the accuracy of restoring original colors from black and white photographs.

Contextual Notes

Some limitations are noted regarding assumptions about color perception and the technical aspects of image representation, with unresolved questions about the implications of the discussed techniques.

rajeshmarndi
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isn't that different intensity of black and white in an old B&W photo correspond to a particular color range of the source.
Which can then be converted into its original color?
 
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No, different colors do no conform to different intensities - play with a color photo and a photo editor and this will become clear to you.
 
My dad, who grew up watching black and white films, claims he can tell the difference between colors in a black and white movie.

Whether or not I believe him is a different thing.

Also I kind of like the contrast of black and white. I think it makes things crisper than a lot of color movies.
 
Redd said:
My dad, who grew up watching black and white films, claims he can tell the difference between colors in a black and white movie.
You sure that isn't just for objects he already knows the color of?
 
russ_watters said:
You sure that isn't just for objects he already knows the color of?
Edwin Land, inventor of the Polaroid camera, would sometimes demonstrate the recreation of an (apparent) color image from two black-and-white slide transparencies using two projectors. Each projector alone projected a B&W image, but both together projected a color image. Here is a website discussing his technique.
http://people.msoe.edu/~taylor/eisl/land.htm
I saw Edwin Land demonstrate this in the 1960's, and was totally surprised by the result.
Bob S
 
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when a color photo is converted into B&W, could that B&W photo be similar to the same souce but with some color changes and converted back into B&W
OR
does any intensity of Black or White correspond to more than one color
 
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Redd said:
My dad, who grew up watching black and white films, claims he can tell the difference between colors in a black and white movie.

Whether or not I believe him is a different thing.

Part of it is the shade of gray, the other part is his knowledge that a banana is yellow, and not pink.

As for colors of unrecognized objects, I don't think so...
 
Bob S said:
Edwin Land, inventor of the Polaroid camera, would sometimes demonstrate the recreation of an (apparent) color image from two black-and-white slide transparencies using two projectors. Each projector alone projected a B&W image, but both together projected a color image. Here is a website discussing his technique.
http://people.msoe.edu/~taylor/eisl/land.htm
I saw Edwin Land demonstrate this in the 1960's, and was totally surprised by the result.
Bob S
Interesting experiment, though your description is somewhat inaccurate. One of the black and white slides was shot with a red filter, then projected with a red filter. So it is truly a red image through and through. Digital cameras work the same way, by using alternating colored filters on a monocrhome CCD.

He didn't prove you can see color in a black and white image, he proved you can see all 3 colors in a red and white image. I suspect, though, that a lot of the reason this works is that there are similar proportions of blue and green in that image. I'll check into it with Photoshop when I get home tonight...
 
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rajeshmarndi said:
when a color photo is converted into B&W, could that B&W photo be similar to the same souce but with some color changes and converted back into B&W
OR
does any intensity of Black or White correspond to more than one color
As I said above, any color can have any intensity. It would help a lot if, as I said above, you play with a photo editor to demonstrate for yourself, but here is a brief description of how a color image is represented digitally:

Each of the three colors is assigned a brightness level from 0-255 and the three are then combined in each pixel to generate a color image. So you can have a pixel with any combination of brightness levels for each color, giving 256*256*256=1.67 million different colors.
 
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