That aligns with experience my new sunglasses. They have a green tint, but they do change to a magenta tint when looking at the lenses in sunlight. It is weird... they look green sometimes, and magenta sometimes. Anyhow when I wear them the fall colors pop! And that's why I started this discussion in the first place. I wanted to do that with a filter.Originally Posted by Policar
I have a Tiffen enhancing filter, and after I read your post I walked around a bit, seeing how its color changes. Depending on the light, it goes from green to neutral to barely pinkish. You really have to put it on a camera and make some photographs to really see the true effect. Enhancing filters are a strange lot.
"Strange" is definitely the word.
Looking at the absorption spectrum for didymium across the visible spectrum, it absorbs relatively little violet, not much blue, a little cyan, almost no green, and then just a tremendous amount of yellow and orange and then no red at all. It absorbs quite a lot of near-infrared and infrared, though, which some cameras (and velvia 100) read as magenta. I really want to see what it does with velvia in the late day, since it might be really weird or it might just end up correcting its magenta cast.
Under any tungsten light the filter looks magenta and under any fluorescent light it looks green. We have a 2700K tri-phosphor compact fluorescent light next to a 2900K high-CRI led light (fancy) and I can walk between the two and anything else looks exactly the same but it shifts from green to brown/magenta. It's just bizarre.
Shooting outside around blue hour it turns everything a bit close to cyan. Going to try again during the day tomorrow. Even highlighly corrected fluorescent lights (my lightbox, my expensive 8-bit lcd) go very green. I shot a color checker chart on a crt monitor (which it renders relatively neutrally) and have posted the before and after results here, averaged out in photoshop. There are a thousand reasons this is a bad, unscientific thing to do so don't bother to tell me. Just thought it was interesting. (The same thing on my lcd monitor just turns green.)
Second one (to the right) is with the filter on.
At mid-day it's pretty color neutral, although shaded areas take on a green/cyan cast.
Some more before/afters of random objects outside. Potentially helpful for any area with both green and red in frame.
Looking at those it makes me think that scanning and digital color balance might be better.
Try Japanese maples against a clear blue sky. Awesome!
Well, my bad snapshots aren't doing the filter any favors. I think it helps significantly in the first one, where it boosts both greens and reds; digitally correcting warm and cold tones separately isn't trivial. It does have an unpredictable tint, though.
For foliage and sunsets...it could be useful. It's certainly not as indispensable as a grad filter or polarizer but I'm excited to try it on film and think it might be just the thing for fall color, as it really cuts out muddy orange brown tones. Unfortunately I got it a month late.
It is pretty simple with a "selective color" adjustment layer (or open the file with ACR and use the HSL tab). I agree with Jack. Given what I see in the examples, my choice would be to just deal with this in post processing. One less thing to buy and carry in the field, one less piece of glass in the mix, no filter exposure factor, more precision, and no unpredictable results.
I took at quick stab of changing photo 1-a to match the color of 1-b. I used a curve to lower luminosity and a color balance adjustment layer.
I also used a selective color adjustment layer only to lower the luminosity of the white rock, and add just a pinch of warmth to the red leaves. But the biggest changes were much lower luminosity in the exposure with the filter and much more cyan in the exposure with the filter.
Posting Permissions
Reply With Quote
Bookmarks