Red Filter?

Aaron Bernard

Ive been doing a lot of black and white conversions lately and was doing some reading in general about B&W. During my reading I came across the idea that people use a red filter (#25 or so) to darken up the sky and bring more contrast into the image. Now Im assuming this would only work on a film camera with B&W film loaded??

Is this correct or is there any use at all on a color digital camera (D70) for a red filter? :dunno

wxwax

A polarizing filter achieves some of the same effects in color. The polarizer saturates colors. It has the effect of making the sky a deeper blue, and greens really pop a well. It's well suited to landscapes.

If you have a digital camera, make sure you get a circular polarizer. A linear polarizer will not work.

4labs

FastScan wrote:

Ive been doing a lot of black and white conversions lately and was doing some reading in general about B&W. During my reading I came across the idea that people use a red filter (#25 or so) to darken up the sky and bring more contrast into the image. Now Im assuming this would only work on a film camera with B&W film loaded??

Is this correct or is there any use at all on a color digital camera (D70) for a red filter?

IMHO I would forget the filter and get the image factory software. It lets you simulate any color filter and I have gotten great results with it...

wxwax

4labs wrote:

IMHO I would forget the filter and get the image factory software. It lets you simulate any color filter and I have gotten great results with it...

I see what you're saying, but I'm not sure you can duplicate a polarizing filter in Photoshop, can you? Color filters, yes, but I'm not aware of a way to mimic a polarizer.

4labs

wxwax wrote:

I see what you're saying, but I'm not sure you can duplicate a polarizing filter in Photoshop, can you? Color filters, yes, but I'm not aware of a way to mimic a polarizer.

I wouldn't think there would be a need for a polarizer if you are shooting BW film?If you just want to darken the sky , just use a red filter in Photoshop.

Aaron Bernard

4labs wrote:

I wouldn't think there would be a need for a polarizer if you are shooting BW film?If you just want to darken the sky , just use a red filter in Photoshop.

OK this is getting funny. Its like that game where you tell someone one thing and then it comes back to you totally differant.

Ive got a polarizer and I enjoy the results from that when I shoot and convert to B&W. Ive also got access to a red filter and actually just tried it.
I get a nice red image... everything is red! not the effect I was looking for. So I guess you have to be using B&W film for the red filter to do its job properly.

wxwax

FastScan wrote:

OK this is getting funny. Its like that game where you tell someone one thing and then it comes back to you totally differant.

Ive got a polarizer and I enjoy the results from that when I shoot and convert to B&W. Ive also got access to a red filter and actually just tried it.
I get a nice red image... everything is red! not the effect I was looking for. So I guess you have to be using B&W film for the red filter to do its job properly.

Yes, that's right. Otherwise, it's just a red filter.

wxwax

4labs wrote:

I wouldn't think there would be a need for a polarizer if you are shooting BW film?If you just want to darken the sky , just use a red filter in Photoshop.

I was just answering the bit where he asked if there was a use for a red filter in color.

Phil U.

FastScan wrote:

OK this is getting funny. Its like that game where you tell someone one thing and then it comes back to you totally differant.

Ive got a polarizer and I enjoy the results from that when I shoot and convert to B&W. Ive also got access to a red filter and actually just tried it.
I get a nice red image... everything is red! not the effect I was looking for. So I guess you have to be using B&W film for the red filter to do its job properly.

You can take that red image and do a B&W conversion from it. You will notice a different look (different tonality) in it as compared to a shot without the filter converted to B&W with the same parameters.

However, you can achieve the same results without having to use the filter during the shoot. There are different B&W conversion techniques out there. During this process you can adjust what colors from the color image you want to use to obtain the B&W tonality you want in the final image. Do a search for B&W conversion techniques and play around with the "Channel Mixer" method - this is an easy way to see what the effects are of using different mixtures of color for the resulting B&W image.

B&W Film photographers use(d) different color filters (I believe Red is probably the most used) to achieve this effect to get the tonality they want(ed).

Aaron Bernard

OK. Im going to try a B&W conversion on the Red image just for kicks. I'll post the results here...

thanks!

Aaron Bernard

I did some shots with the red filter. Check it out here:

http://www.5road.com/redfilter/index.html



See the results for yourself. In the end the images almost look the same. I did an auto levels on both the color version and the red filter version just to see how it would come out. At 100% the red filter version is much less noisy than the color version. Could be the quick conversion method I used though. At any rate this test shows you can use a Red filter on a DSLR to do B&W. Dunno if there is a reason to yet but it will work. Im going to play around with it some more now that I have the filter.

One side effect is that the red filter cuts down your stops almost like an ND filter.

blackwaterstudio

IF you have a Canon 20D you can set the red filter in the camera to whatever you like while turning off the blue and green channels.