B&W enhancing filters

[qnardi]

Hi,
Am looking for help and info on filters that enhance b&w daylight film.
Mainly for portrait work...is there a filter that can yeild a warmish overall feel and give a boost to whites? Any imput would be much appreciated!
Thanks!!:thumbup:

 

[Hertz van Rental]

If you are shooting in B&W then you won't get a 'warmish feel' - it'll just be black and white.
You can warm up the blacks in the print depending upon the paper/developer and after treatments like toning.
But you won't get a 'warm' effect by using filters.
Same goes for the whites.
Correct exposure and then a bit of darkroom magic is what you need.

PS Daylight or Tungsten - it makes no difference to B&W film.

 

[qnardi]

then b&w filters mainly help with contrast? do they do anything else?

 

[Unimaxium]

B&W filters (not to be confused with B+W filters, which is a particular brand name of a german filter manufacturer) are used to change what colors of light show up as brighter on your B&W shot. For example, let's assume that without a filter, a scene containing three chairs that are red, green, and blue renders all three chairs as the same brightness in the photograph. Adding a red filter will partially block blue and green light, causing the red chair to appear brighter than the others. Adding an orange filter will have a similar effect, except it will not be as intense, and a yellow even less so. Using a green or blue filter will cause the same effect for the green and blue chairs, respectively. In a more practical situation, a red filter can be useful for darkening a blue sky in a landscape scene, or a green filter can be used to lighten foliage, etc. So filters are a means of adjusting the contrast of your scene to favor objects of certain colors. Depending on the colors in your scene, they can either serve to boost or reduce contrast in the final image.

 

[Hertz van Rental]

Not really.
Their main function is to change the visual contrast between objects of different colours that have the same tonal value.
For example, you could have two objects - one red, one green - that have the same tonal value so come out the same shade of grey on B&W.
If you want to separate them visually then using a red or orange filter would lighten the red a little and darken the green a lot. Using a green filter would do the reverse.
On a landscape you can darken the blue sky and make clouds stand out using yellow, orange or red (increasing contrast in each case).

 

[Garbz]

here's a visual example for you. The following flower is bright red, the background is green and brown, the things hanging out of the middle of the flower are yellow. On the image of the left the red and green had the same tonal value so the flower is rescessed, the things however are brighter being yellow.

On the right add a #25 Red filter which only lets red light through. As green has little red content, and the yellow now has all of it's green reduced the flower stands out from the background but the things are lost:

The following picture of a flower with red and green leaves wouldn't be possible at all without a red filter. The image is inverted if a green filter is used:
http://i12.photobucket.com/albums/a241/Garbz01/black and white 1/bw3.jpg