B&W Filters when Scanning Film

[bwcolor]

I recently shelled out money for medium yellow and red(8x) B+W filters, but noticed that, especially with the 8x filters, that one can not always bring up detail in the shadows, whereas shooting without these filters effectively increases EI..no filter factor.. and similar results are to be had in the digital arena.

Why do you use B&W filters in a digital workflow? When and why do you use them?

 

[Frank Petronio]

I don't know why anyone would use colored filters when they shoot RAW digital files from a digital camera? Jpgs are a different story.

Colored filters on a film camera are a different story. It doesn't matter whether you scan or use a darkroom, the information that is in the negative is all that matters. Your red and yellow filters will deepen the skies and darken the shadows with conventional B&W film but you'll have the same plugged shadows whether you go analog or digital. Your only solution is to find the right amount of exposure/development to put detail into the shadows while maintaining pleasing contrast.

There is no sin in bracketing.

 

[bwcolor]

Why not just do this in post-processing?

 

[nathanp]

Why not just do this in post-processing?

You can't if you're shooting on B&W film..

 

[bwcolor]

I posted this because in another thread, it was suggested that you could imitate filters when shooting B&W film through the use of PS. I assumed that we are talking about selectively increasing the contrast in the sky, or some such task. I have found it easy to increase, or decrease contrast, or to do so selectively in the highlight, midtone, or shadow areas, but to imitate a B&W filter in PS seemed to be more than a trivial task, which would take more time in PS than to shoot with the filter in B&W. On the other hand, imitating a more subtle filter, for example, using a medium yellow to enhance a portrait, might be less of a challenge in post processing.

 

[Pickett Wilson]

Nik software's Viveza.

 

[bwcolor]

I just watched the video on Nik's site re: Viviza 2. It seems to do what filters might accomplish. It doesn't seem to be a matter of can I do this in software, but how much time am I spending doing it vs using the filters where I have to ask myself, how well am I controlling the exposure/development process. Right now, the answer to the second question is I'm not properly controlling exposure/development. Viviza looks great. I think that I'll wait for a while to purchase. I want to make sure that it works well with AP3.

 

[Dwig]

... but noticed that, especially with the 8x filters, that one can not always bring up detail in the shadows,...

If there is not enough shadow detail you underexposed the image, period.

The filter factors are only vague guides. They only approach any form of accuracy when photographing neutral gray objects (black, white, or some gray in between). When a subject is strongly colored, that object many be affected by the filter more or less than a gray object.

With red filters (Wratten #25 and equiv) objects that are blue or green are affected substantially more that the mean gray. If the objects in your shadows are blue or green the effective filter factor for them could easily be 16-64x. After all, that is the point of using a red filter; to darken blues and greens more than grays and darken reds less.

 

[degruyl]

With red filters (Wratten #25 and equiv) objects that are blue or green are affected substantially more that the mean gray. If the objects in your shadows are blue or green the effective filter factor for them could easily be 16-64x. After all, that is the point of using a red filter; to darken blues and greens more than grays and darken reds less.

(this is probably pointless, but why not)

Most of the light in shadows is blue light scattered in the atmosphere (skylight). Therefore... a yellow (or especially: red) filter will take away most of the light in the shadow. You can't get it back.

If you have a spot meter, you can put the filter (or one like it) on the spotmeter, before you take you shadow reading.

You do get used to this, though.