Reflection from silver grains in old photographs
Cyril & Sandy Alberga
I am getting clouds of blue speckles, which I think are from silver
grains in the emulsion. Does any one have a suggestion for either
avoiding these or eliminating them?
I am also posting this in the Corel Photopaint group.
Cyril N. Alberga
Ken Weitzel
Hi Cyril...
I find the same with a few very very old prints that I scan.
Only solution I've been able to find is to use paint shop
pro's salt and pepper filter followed by a little edge
preserving smooth.
Hopefully others will have better suggestions.
Take care.
Ken
Cyril & Sandy Alberga
These tend to be photos that are 80 to 100 years old. I'm a Corel user,
so I'll have to see if Photopaint has analogous filters.
Thanks for the reply.
Cyril
John
news:HYjPe.4024$IG2.1830@trndny01...
Assuming you are talking about monochrome prints.....
I sometimes find that most of this type of noise is worst in the blue
channel. I tend to scan as full colour, then overwrite the blue channel with
one of the others which has less or no speckles. Sometimes I just use the
red channel only. Then desaturate and re-tone as necessary. Use 16 bit
though to be on the safe side.
--
John
Replace 'nospam' with 'todnet' when replying.
Cyril & Sandy Alberga
Thank you, I'll try that. And yes, they are (sort of) monochrome.
There is quite a bit of yellowing, and some may have been printed as
sepia, although I can't always tell that from the effects of age.
Cyril
John
>
> Thank you, I'll try that. And yes, they are (sort of) monochrome.
> There is quite a bit of yellowing, and some may have been printed as
> sepia, although I can't always tell that from the effects of age.
>
> Cyril
I restore a lot of old photos and often come across the sort of thing you
describe. It is always worth looking at the individual colour channels,
particularly with toned or yellowed prints - one of the channels will often
stand out as being much cleaner than the others and the technique can often
remove other blemishes as well as the silver speckles.
Good luck!
Cyril & Sandy Alberga
I tried splitting RGB, but all the channels had some of the speckling.
Then, for no good reason, I tried CMYK. To my surprise the Cyan channel
was almost completely free of speckles. To me this doesn't make sense,
as I would expect Cyan to pickup a lot of the blue, but I can't argue
with my eyes.
Perhaps you have an explanation, but with or without one I thank you for
pointing me to this. I don't think it is placebo effect!
Cyril
JWSM
silver polish - quick sponge rub over then remove with wet sponge before its
dried, followed by drying with a hair dryer on gentle setting. Never had a
problem, and the photographs are still relatively free of mirroring 10
years later (indeed they have not visibly deteriorated in any way).
If dark shadow areas are showing signs of mirroring, there is no way a
scanner will pick up the detail. Old photographs are quite resilient (I
wouldn't use this method on flaking emulsion), and you can selectively
apply the silver polish to only the dark areas.
Am unsure if there is an alternative product available or method. If you
wet the area it vanishes momentarily, then reappears when it's dry.
Anything else I thought of seemed like it would be difficult to remove /
clean, or might affect some of the decorative card borders.
It's perhaps scary to many people, but I have extremely good 5x4 negs and
scans that didn't require artwork to reinstate detail, which produce
flawless copies of how the original photograph was intended to look.
J
Robert Feinman
says...
The light source is perpendicular to the surface as is the
sensor so you get lots of reflections.
The only way to overcome this is to rephotograph the original
with a standard copy setup. That is two lights set a 45 degrees
and the camera in front. Extremely difficult cases require
polarizers on the lights and on the lens.
A book on copying will explain all.
--
Robert D Feinman
Landscapes, Cityscapes and Panoramic Photographs
http://robertdfeinman.com
mail: robert....@gmail.com