Kodachrome and Infrared

[Chuck Forsberg WA7KGX N2469R]

My Canon 9950F interprets dark objects in a contrasty Kodachrome slide
(backlit cacti) as dust, and tries to rub them out as if they were
dust.

Has this been seen with other scanners?

 

[Don]

My Canon 9950F interprets dark objects in a contrasty Kodachrome slide
(backlit cacti) as dust, and tries to rub them out as if they were
dust.

Has this been seen with other scanners?

Yes!

I'm not familiar with 9950F specifically, but if you're referring to
ICE (i.e. infrared cleaning of dust and scratches) Kodachromes contain
silver particles which ICE/infrared confuse for dust.

That's the same reason why ICE doesn't work with conventional
(silver-based) B&W film.

Since there is no one type of Kodachrome depending on vintage ICE may
work with some of them. Also, the brighter the image is (i.e. the more
silver has been washed out) the better ICE works. I have a set of
really dense Kodachromes with lots of silver and yet ICE worked just
fine on one overexposed slide while it choked on all the rest.

Don.

 

[Roger]

My Canon 9950F interprets dark objects in a contrasty Kodachrome slide
(backlit cacti) as dust, and tries to rub them out as if they were
dust.

Has this been seen with other scanners?

Kodachromes, or at least a good many of them are known for not working
with IR cleaning. Just turn the IR cleaning off.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com