Cloud Separation

[Kirk Gittings]

I used to give my photo students a "color sensitivity" lesson. The students were to describe the colors they saw in clouds. It was a simple lesson in observation. I never talked to one of them that wasn't amazed by what they saw. The students had never looked closely at clouds before and had always assumed they were neutral. They almost never are truly neutral or monotone.

[Sheldon N]

Well... some of the clouds we get here in the Northwest can be monochromatic. We get that lovely sheet of solid gray with no shape or form. With this kind of sky, the only thing that a filter does is keep the rain off your lens!

Sometimes I think that we just get one big cloud that rolls in around November and finally passes by sometime in March.

[Kirk Gittings]

I could have been clearer I guess. I was talking about clouds not completely socked in, slit-your-wrists overcast.

While I love the NW, I would have hated trying to make my living there shooting architecture. Here in NM you have to wait about a few hours for any major weather change so we can shoot like 98% of the days. I would starve to death there from Nov-March. Work Starbucks in the off season?

[Kirk Keyes]

I would starve to death there from Nov-March. Work Starbucks in the off season?

You could do that. A couple frappachinos every day has enough calories to hold you for several months.

And we have a Starbucks (or some other coffee outlet) on nearly every corner. I think they are the equivalent for college graduates (English, Humanities, General Studies majors) that gas stations are for high school dropouts.

And if you tire of coffee, you could always get a job at Powells Books...

[Vaughn]

I could have been clearer I guess. I was talking about clouds not completely socked in, slit-your-wrists overcast.

This is the type of overcast I am use to here in the NW..but actually it creates wonderful light to photograph in under the Redwoods (especially from about 10 am to 2pm).

But Kirk, I very much appreciate your observations about clouds. I will observe clouds differently now...and that is a fine gift you have given me. I hope I can return the favor, or at least pass it forward.

Thank you,

Vaughn

[chris_4622]

I was hoping Kirk Gittings would weigh in with his experience and love of photographing under these conditions.

Thanks to all. Just to clarify; there was no rain or mist present, there was a lot of contrast in the clouds. I wasn't sure if a filter would help.

I can't wait for stormy conditions to go out and "play".

chris

[Brian Ellis]

Brian,

I've always read, and found it to be accurate, that balck and white filters also reduce or eliminate atmospheric haze. That is the specific reason that Adams cites for using the K2 on the "Clearing Winter Storm' image.

Also, we can't see all the colors (back to UV) that the filters and film effect.

By removing both the UV and the haze, the filters do enhance contrast even though we may not recognize actual colors visually in a scene.

Tm

Tim - I didn't say anything about using filters to remove haze except that it was a different question (i.e. a different question than the OP asked because he asked about using filters with gray and white clouds, he didn't say anything about haze). With respect to not seeing all the colors that filters affect, that's certainly true but I don't see that it's very relevant to using filers. If you can't see the colors why would you think of using filters in the first place (setting haze aside) and even if you did think of it, how would you know which filter to use?

[lenser]

Hi, Brian.

Of course you are right that you didn't mention haze, but I believe that it is a component of the answer to the OP.

Haze is made up of water vapor, microscopic dust particles, and UV.

No filter will deal with the dust. A polarizer and any contrast filter will help with the water vapor, and the range of contrast filters help to deal with the UV.

If you've ever shot transparency film on a cloudy day without filtration (especially a portrait in the shade) you'll recognize the UV in the blueish skin tones and shadows. At high altitudes the skies go nuts with blue (which can be wonderful) but the shadows go extremely blue without a warming filter. (Thinner atmosphere has a much higher UV to other colors balance.)

Since black and white films are usually very blue sensitive, the unseen, blue related UV actually seems to lighten skies and create more atmospheric haze.

Since a cloudy day produces a heavier balance of UV to the rest of the spectrum, it's extra blue related component might actually create a bit of a veil of extra exposure on the clouds. This will lessen contrast and tonal separation. So, the yellow, orange or red filters will enhance the contrast between the clouds unless there is no variation in tone across the sky.

You still have to make all the same decisions about which filter and the combination of exposure and development to create the print that you visualized to begin with.

As far as how do you know which filter (if you can't see the UV).....that's still a personal preference on how much contrast you enjoy in your prints. Nothing could have a richer range of tones than Adams "Clearing Winter Storm" and yet it needed only a light yellow K2.

After all that, do you need a contrast filter to shoot clouds? No. Does it have the potential to separate tones and create more contrast? Yes.

Like everything else we shoot, it's a matter of what we personally like in the prints.

Have a great day. (By the way, I love your signature quote.)

Tim

[Mark Sampson]

Trust me, don't over-filter. I have a negative from last week of clouds with shafts of sunlight on the beach- it's way too contrasty, the proof looks overdone. I'm going to have to a) work hard printing it and b) retire the #15 filter. 25 years of practice and still things to learn!

[Erich Hoeber]

I find that filtration will often make a big difference in separation even when no blue is obvious. There's still a lot of blue in there, although it's sometimes difficult to judge exactly how strong the effect is going to be. I frequently will make shots with two different filters, so I'll have an option.