Recovering faded photos with Infrared very techie stuff
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In reply to:
Re: Recovering faded photos with Infrared
Paul 8/30/02
Paul,
You seem to know you photo science.I remember reading about recovering old photos with non visable light.I have also noticed that some scans are better than the original.I chalked this up to the extra magnification on the viewed image.My light source appears to be some sort of excited gass lamp which produces a very bright light with maybe a greenish tint to it.It is hard to say because it is so bright.It is good on darken stuff as well the light can penatrate the ultra dark back round of the paper making a contrast of the slightly darker print.
I have many, one of a person, photo that are faded.I play with the contrast which will recover a little fading.I would love to enhanse these if it did not cost much.
What I think you were saying is some scanners scan in the non visable range because the light source has non visable wavelengths and the light receptor is sensitive and records both visable and non visable light.Am I correct?
I am trying to understand the fading process.Is the dark part of a photo a silver salt?I know the photo-active (the negative for most kinds of pictures) is silver.
It doesn't really matter, but it makes more sence if the pigment itsself was slightly photo sensitive.For some reason, prolonged exposure to light changes the pigment chemistry back to clear or very light.At this clear stage they still "hold color" ia a non visable wave length.
So what we should be looking for in a scanner is range of light it will record.Do all scanners use the same recording technology?If so, only the quality of the light will matter.
I know I asked some real crazy questions but who knows maybe you have the answer.
More Replies:
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Re: Recovering faded photos with Infrared very techie stuff
Paul 9/06/02
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Re: Recovering faded photos with Infrared very techie stuff
Ron Mesnard 9/06/02
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Re: Recovering faded photos with Infrared very techie stuff