Filtration in the Peruvian Andes

[B Griggs]

I plan to photograph Inca architecture and Andean scenery in May, in Cuzco, the Sacred Valley, and the Lake Titicaca area, and am concerned about filtration in mostly black and white (T-Max 100) but also in color transparency (Ektachrome, K odachrome 25 and 64, suggestions greatly appreciated here). This is high altitud e (7500-11000 feet), but is not as dry as I am used to at that altitude (Colorad o). I have looked at the photographs of Martin Chambi and Edward Ranney, but the ir books do not have filtration info; I have read the existing threads for filtr ation but I still have some questions: 1. In what situations should I be leery of a polarizer? 2. What type of UV filters should I use at this altitude? I see that many are no t up to the task. 3. I anticipate using a yellow filter along with a polarizer for a great deal of this. Is this wrongheaded? 4. What has worked for people in this situation, especially in black and white, and especially since T-Max has a built-in insensitivity to blue? Thanks very muc h.

[Natha Congdon]

I have heard it said that, in addition to more UV light, which can be compensated with a filter, the big problem is lack of the diffusion we are used to from actually having an atmosphere over our heads down here at sealevel. Thus, the shadow-sunlight contrast tends to be much sharper, leading to empty shadows if exposed as one commonly would. I would think that the usual techniques to reduce contrast range (longer exposure shorter development) would be of some help here, at least in B+W. As I mentioned in another thread, I will be in the same boat in May, tho' I will be shooting for Platinum, and may just expose for the shadows and assume that Platinum can handle whatever highlights result.

Buena suerte! Nathan

[Matthew Cordery]

Martin, at that altitude the last thing you're likely to need is a polarizer. I've shot transparency film in the mountains in New Zealand and in the Sierra and I never use any filtration. When I just started out, I did use one and I can guarantee you that it will just make your skies close to black. If I were going to be using color transparency film at high altitude, I don't think I'd use a UV filter but rather a color correction filter (warming filters). You should be able to work out what sort of color temperature your light will be and then work out the kind of filters that you need to correct back to "normal" daylight color.

[Steve Feldman]

Burke,

My experience with trans film at altitude is - Don't over polarize. At sea-level a polarizer is appropriate to make a bland pale blue sky a darker blue, thus bringing out the clouds. But at higher elevations a polarizer will make a blue sky VERY dark blue to nearly black. Try a few sheets in your area first and know for sure.

Also, trans film is contrasty enough on it's own. Hope for moderate over-cast skies.

Good light, good trip.

-Steve

[Henry Ambrose]

For the color transparency work consider either a KR3 warming filter from B+W or simply take a warm film, E100SW. Its a -little- warm so will look good at high altitudes without a filter. I would not bother with 3 different films that are s o similar. Just take one film and the KR3. Use the filter when you're up high, t ake it off when you don't need/want the effect. If the polarizer is for blue sk ys only, then leave it home, your skies will be dark enough at altitude. Contra st filters will be useful for your B&W work.

[Eric Pederson]

Just a naive comment to add to this thread:

All of the above responses seem to be assuming that a pol filter is just for darkening the sky. With direct sunlight on ruins and plants, you might well want a pol filter to minimize reflected glare (at least under some conditions). In other words, darkened blue skies might be the risk, not the goal, of such a filter.