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ktixx
02-03-2005, 03:10 PM
Has anyone used the Black and White settings on the Canon 20D? Within the camera menu you can apply digital filters (IE: yellow, orange, red and green). Does anyone know if these digital filters are as good/do the same job as normal glass filters? I realize that the same effect can just be applied in photoshop, but I am wondering if it is worth carrying glass filters if the digital filters on the camera will apply the same effect. Any input is much appreciated.

jeisner
02-03-2005, 03:29 PM
Carrying glass filters IMHO has become a little bit of a waste of space with digital. I still carry a ND filter and a polariser but thats it, warming and colour filters can be applied in photoshop or as you say on the camera (I would prefer to use photoshop).

dwig
02-03-2005, 07:19 PM
The "digital filters" should so a similar job to the basic versions of the real filters commonly used for B&W photography but not the more special narrow band filters. Digital filters work by altering the color to B&W conversion that takes place in the camera. Once you have the B&W image there is nothing that can automatically do the same thing, even in powerful editing programs like Photoshop. The necessary color information is gone. To do the work in Photoshop, et. al., you would need to shoot in color and let PS do the color to B&W conversion after applying some form of digital color filtering/adjustment.

I don't have any personal experience with the algorythms in the Canon camera though I've done this manually in PS. They probably work well for most common scenic needs (green to lighten leave relative to the bark or red to darken the blue component in skys, ...) but I wouldn't expect them to work for more demanding scientific/forensic use where very specific portions of the spectrum need to be either photographed or avoided.

eagle17
02-04-2005, 11:32 AM
I shoot with raw on my 20D and then post process to B&W. if you are too intemidated by photoshop then you can use the built in filters, otherwise you will get better results with photoshop.

ktixx
02-05-2005, 03:09 AM
I am actually pretty proficient in photoshop, I just was wondering how well the digital filters work compared to the glass ones. Pretty much everyone says the same thing (you won't notice the difference). Thanks for your reply's
Ken

dwig
02-05-2005, 07:07 AM
I am actually pretty proficient in photoshop, I just was wondering how well the digital filters work compared to the glass ones. Pretty much everyone says the same thing (you won't notice the difference). Thanks for your reply's
Ken

As I mentioned in my first post, for the less demanding pictorial use, digital "filtering" in PS (_prior_ to conversion to b&w) works very well and yields results comparable to the common traditional b&w filters (Wratten #25 red, #11 green, #8 yellow). More demanding shots using the narrow band-pass filters needed for some scientific and forensic work are hard or impossible to simulate.