Digital BW, The Print

An 87 filter is mainly transparent to infra-red, but does allow a very small 
amount of red light through.

It depends upon the camera just what you get. It's not just red, because the 
green and blue filters on the image sensor are generally just as transparent 
to infra-red as the red one, so the image is nearly monochrome.

On my Canon Pro 70 it yields a perfectly monochrome image, this camera has a 
CMYG filter on its CCD and all four colours seem equally transparent to 
infra-red.

Other cameras with RGBG filters may yield slightly reddish images as that 
visible red component has a slight effect.

On Thursday 17 Jan 2002 4:29 pm, Jerry Olson wrote:
> Carl, The search engine isn't working, do you know what page those
> images are on?
>
> Once you've taken a photo with the red filter, I assume you'd have a
> very red photo. How do you change it to Black and white infrared?
>
> Is an 87 filter the opaque one, or just a very deep red?
>
> Thanks
>
> Jerry
>
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