Differences shooting at high altitude?

[nes_suno]

<P>Are there any special recommendations for taking

pictures (B&W or color) at higher altitudes (let's say

5000 ft. (1500 m.)?

 

<P>Specifically I'm looking for filters and other exposure

compensation information. I'm assuming that UV levels are

higher and guess that snow is problematic for metering.

 

<P>Also does barometric pressure or air density and composition

affect film in a noticeable way?

[bob_atkins]

A UV filter is often recommeded since the higher you

go, the more UV gets through the atmosphere. UV tends

to give a blue caste (it affects the blue sensitive

layer of color film). A slight warming filter like

an 81A could also be good (they cut UV plus a bit of

blue). I'm not sure there is much

of a problem at only 5000ft though.

 

<p>

 

The only effect of air composition is that you can get

scattering if there is a lot of dust (or water vapor)

in the air. A polarizer can help here, and, since blue

light is scattered more than red, a warming or UV filter

will theoretically help (a bit). For B&W you can go all

out and use a yellow or even a red filter to help cut

through haze.

 

<p>

 

Pressure and air density have no effect on film at any

altitude you are likely to get to!

[jboucher___]

Hi Sean! I have photographed fom sealevel to almost 20'000 feet - there are things to look out for. A polarizer can help, but be really careful with it. It is very easy to turn blue skies black. There is useally a lot of light being thrown around from snow and ice covered mountain faces - meter something very neutral and midtone, bracket a 1/3 stop on each side, you will probably like them all. In snow it really is easier than you think. When I'm in Churchill with the Polar bears, I typically meter off the snow next to the bears (same light) and open up 1 1/2 to 2 stops. Works great, you get white snow and cream colored bears (they actually arent very white except for the babies) the light at altitude isn't as filtered as down low - I hve had so so luck with UV filters, some have turned my snows a bit magenta. Because the light is so blue up high, I use an 81A and 81B quite a bit. Sometimes I leave an 81a on all the time if its sunny.

Beware the grey snow!!!!

Cheers!

Jeff B.

[thom_hogan]

According to Galen Rowell at a photo trek I went on, current films don't have the problems with UV that the older films did (they were sensitive to the UV spectrum). He doesn't usually use a filter, even at the altitudes we were at (between 11,000' and 17,000'). Haze and contrast, however, are problems you'll have to deal with. A polarizer helps with the contrast (if it doesn't blacken the sky--don't set it all the way), as do graduated filters. If your camera will take Lithium batteries, consider using them instead of alkaline, as battery life will shorten as it gets colder.

[nes_suno]

<P>One thing I've learned in the past few days is that Ni-Cad batteries apparently are less affected by cold than off the shelf alkaline batteries.

 

<P>Although the latter have less capacity to start with, they don't feel the bite of cold temperatures as readily as standard cells.

 

<P>BTW, thanks to everyone who suggested a polarizer. I have a Tiffen circular polarizer that I use sometimes as a pseudo-neutral density filter to lengthen exposure/use smaller apertures and have noticed the color saturation and light polarization changes in using such a filter.

[alec_pytlowany]

Sean: all the answers above have good info to follow. I work as a ski photographer in the winter and live and shoot in the Rockies all year round professionally. I do not use UV filters at all at any altitude or really ever (personal preference, I don't see much difference)but I do use polarizers very often. My experience is between 5,000' where I live to 11,000' up to where I commonly shoot. I do not have problems with skies becoming black unless the film is underexposed. I have shot aerials from 30,000 feet and still have not found skies to go black, but I guess it can happen. Altitude does have haze, pollution, more or less depending on the day, the weather. Regarding using an 81A or B, or even Kodak SW film, I'd suggest it depends on the time of day and what you expect your results to look like. I find that if you are shooting mountains with snow or a lot of white, then to keep the snow white (with natural bluish shadows) then don't use the warming filters or snow during the white light part of the day (11am - 3pm roughly)as my tests show that it casts an unnatural yellow to the snow. Test several poloarizers to find a colour that you like and use it if you can. Yes, my experience shows every brand of polarizers is slightly different in its rendition of colour and exposure. If you are shooting early or late in the day, then the 81A etc will fit/enhance the light, but a polarizer may also be of use to cut through haze, increase contrast and colour, so you could stack them or do you use the Cokin type system?

 

<p>

 

Higher altitude doesn't seem to affect film. Your exposure could/will change on a sunny day by may 1/2 stop as the light may be that much more intense, but not always. I use a handheld meter always, which is unaffected by the snow in the scene. If this is a one time irreplaceable shoot, and you don't have a really sophisticated in camera meter or the ability to bracket, then consider a hand held incident (not refelctive) meter. (There are so many variables to what you are shooting that one could go on and on here with pros and cons.)

 

<p>

 

As well, the advice regarding snow readings above is accurate. I religiously use +2 stops off a snow reading using my in camera meter.

That is for exposures of my taste, with my camera meters, with how I use them. These vary with everyone. So my advice to you is to test some E6 film taking exposures off of a large sheet of white paper in the same light as your test subject. Using an in camaera meter, fill the viewfinder with only white, no shadows and no texture. With snow (white) this is critical. Then bracket 1/2 stop + and - to 1 stop at least either side. Keep the white paper in the shot to view how exposure will affect white. +2 stops usually matches my hand held incident meter which is recalibrated for the exposures that I like after purchase.

 

<p>

 

View the results and decide what you like. If this is for publication, most mags I work with like a lighter slides, as well lighter slides are easier to view/project in slide shows. But, slightly darker slides make better Cibachrome prints or really any kind of print. My view of light and dark here is not over and under exposed by more than 1/3 to 1/2 stop from say the sunny 16 rule. Everyone's eyes and tastes are different, so you must test, test, test, your film, lenses, cameras and polarizers to find what you like. Also I have several polarizers and that I use with several lenses each and most are used at +2.5 stops but one polarizer I need to open up +3 stops. (Remember I'm usually using a hand held meter. An in camera meter should do this automatically, but there are other variables with in camera meters to consider.)

 

<p>

 

Finally, this is great if all we are talking about is distant scenics.

If I'm shooting close ups or action shots, 5-100' away?, I don't use any filters at all! If I'm shooting macros, then I might use a polarizer to remove some reflections, but I'll probably diffuse the light first or cast a shadow on the small subject.

Hope this helps as well.

[kaetheko]

When I head up into the Sierras above 6000 or so I usually carry a circular polarizer and the Cokin P series split neutral density. I find that I use the split nd more because of the flexibility of the size, although I would like to get the Singh-Ray set someday. The Cokin filter is not that dark, so I occasionally borrow my hiking partner's, and the stacking is not noticable on scenics. I find that often on those fabulous view shots you have too much contrast between a noon sky and the foreground or even the closer mountain ranges and I don't have the luxury of hanging around until the light is right as I need to make the miles before dark. (ps. I shoot Velvia) I am careful about over-polarizing as it makes a shot look flat or lifeless, (to me). Have never had a problem with black sky.

[waikit_lau]

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