Really yellow filters

[Ed Richards]

As I understand color filters, both yellow and red should knock out blue to the same extent, but that yellow, as a constituent of green, should do less damage to foliage than red.

So why is it that I can not find any deep yellow filters (+3 stops) equivalent to a red 25? Anyone tried stacking yellow filters to see if you can get a strong sky and not get black foliage? (This is less relevant if you have high mountain skies but is a big issue on the Gulf Coast where you often need a R25 to get any darkening of the sky.)

[Nick_3536]

#15 is the darkest yellow. A #12 which is lighter blocks all blue. The #15 will block all the blue and some green [I think green]

[Nick_3536]

BTW if you don't want to go to the #25 have you considered a #21? Dark orange?

[Bruce Watson]

As I understand color filters, both yellow and red should knock out blue to the same extent, but that yellow, as a constituent of green, should do less damage to foliage than red.

So why is it that I can not find any deep yellow filters (+3 stops) equivalent to a red 25? Anyone tried stacking yellow filters to see if you can get a strong sky and not get black foliage? (This is less relevant if you have high mountain skies but is a big issue on the Gulf Coast where you often need a R25 to get any darkening of the sky.)

Partly it's the nature of the beast - it's difficult to make a yellow of the hue and saturation that you seem to want.

But I know where you are coming from. I don't use filters much because they seem to throw the tonal balances off from what I want. But when I do want a filter, the yellow filters just don't seem to be enough sometimes, but red seems just too much. My answer has been a #22 orange filter.

The filters I carry with me keep dropping in number too. I'm down to just three - a #15 yellow, #22 orange, and #11 yellow-green (which does a nice job lightening green leaves - useful with magnolias and other dark leaved plants). I don't even carry a polarizer any more.

[Ron Marshall]

If you are not using a very wide lens then try a #12 and a polariser.

[Helen Bach]

...Anyone tried stacking yellow filters to see if you can get a strong sky and not get black foliage? (This is less relevant if you have high mountain skies but is a big issue on the Gulf Coast where you often need a R25 to get any darkening of the sky.)

Isn't the difficulty caused by the spectral distribution of the light from the sky having a gradual decrease as the wavelength increases rather than a sharp cutoff - so there is some green in a blue sky. This is quite obvious if you work in colour - there is some sky response in the green-sensitive layer. A filter that does not block green may not be able to produce a black sky.

Best,
Helen

[Brian Ellis]

Wouldn't an orange filter do pretty close (not identical but close) to what you want, i.e. darken the sky more than a yellow filter and with less effect on greens than a red filter? I almost never use a filter to darken skies any more, it's so easy to do that in Photoshop where it can be done without affecting anything else in the scene. And when I did use filters it was usually to alter tonal balances in the scene and prevent merger of colors (e.g. a green or red filter to make a red apple stand out from surrounding green leaves). But when I did use filters to darken a sky in b&w photography a medium orange was my favorite.

[Bill_1856]

"Just shoot it straight and you can fix it in Photoshop." Unquote.

[brian steinberger]

A #22 orange filter is excellent. I'm finding it more and more to be my favorite filter for darkening skies as well as the polarizer. But I would recommend the #25 or #29 red filter also. I know that results with a #29 can be "dramatic," but only when the light is actually dramatic. On a normal sunny day, with blue skies and and puffy clouds, the red filter can create very nice results. I'd recommend a #15 yellow, #22 orange, and #29 red. I like those three along with a polarizer.

[Henry Ambrose]

Along with the orange filter mentioned by several, an increase in exposure and less development will help bring the green foliage up. Try a 22 or 23 orange, maybe even a 25 red filter. But the increase in exposure and less development is important to help move the green densities toward the sky densities.