Anyone used a Red filter with Orthochromatic film?

[Pirate]

I love 25 ISO film but I'm only finding it in Ortho these days. I have used Ortho and I don't really like the reds falling to blacks in some pictures, so I was wondering if a Red filter would help keep the colour fallout at bay, even just a little.

Anyone tried it?

Thanks

 

[Dwig]

I love 25 ISO film but I'm only finding it in Ortho these days. I have used Ortho and I don't really like the reds falling to blacks in some pictures, so I was wondering if a Red filter would help keep the colour fallout at bay, even just a little.

Anyone tried it?

Thanks

Filters don't add; they only take away...

True ortho films are blind to red, hence the scene's reds reproducing extremely dark. There is no possible way that any filter can add red sensitivity to the film. If a filter, like a red #25 or #29, blocks all colors other than red it is blocking all of the light that the film "sees". The result is no exposure.

If the film has some small sensitivity to red you might get some exposure, but the filter factor will be massive, many stops more than the usual 2.5-3.5 stops seen with pan films.

 

[Pirate]

I was hoping it would make the reds a little brighter so the darkening of the red would not be so drastic. I'm not looking to make a huge change, only to make the darkening of red just a little less severe. That was my hope.

 

[sevo]

You might just as well use a black filter. ;-) Even light red (25) has a spectral response not that different from the darkroom illumination you can handle Ortho film by.

 

[sevo]

I was hoping it would make the reds a little brighter

Can't be done with Ortho film - there is no way you can increase a zero spectral response.