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John Kasaian
5-Jun-2005, 14:27
What are your thoughts on filters for blue glacial ice on B&W film? I have no idea what the lighting conditions will be like---it will be early morning sun and hopefully I'll have some graim texture visible, but it could just as likely be overcast and resemble dirty cake frosting. I don't get to this part of the hill very often, and I'll be limited as to the number of film holders I'll have, so theres not much chance for experimentation. I don't expect to have much sky in the shot It would be nice to have some sinister looking clouds for drama, but in the past its usually CAVU---(or maybe CCESA---Crystal Clear and as Empty as my Savings Account!) I'd be grateful for any recommendations, suggestions etc...

Cheers!

Ernest Purdum
5-Jun-2005, 15:44
Until I went to Greenland, I thought of icebergs as being as colorless as ice cubes. (Neither a recommendation nor a suggestion, just a comment.)

Alan Davenport
5-Jun-2005, 15:47
I'd consider a polarizer, mainly to increase color saturation. I'd also lean toward a cooler film such as Ektachrome (old: E100S / new: E100G) and stay away from the warmer films like E100SW/E100GX even though those are my favorites normally. E100VS might be good but I'd take along the E100G and shoot both until I knew for sure what the VS would give. I'm assuming you want to accent the blue ice...

Hans Berkhout
5-Jun-2005, 16:22
15 or even 23A to increase local contrast (darken the blue ice and shaded areas), you could still add a polarizer depending on the sky appearance (multiply the exposure factors). And or burn the sky during printing.

Jim Rice
5-Jun-2005, 18:08
Why not the obvious UV?

Hans Berkhout
5-Jun-2005, 22:24
The role of UV filter in B&W context is not obvious to me. 15 0r 23A will block most or all UV.

Ole Tjugen
6-Jun-2005, 00:33
Yellow, orange or red will deepen the blues of ice just as well as sky. But there's a danger of overdoing it so that the ice looks even dirtier than it is, so try some shots without filter too. Mind the inherently high contrast - glare spots on white ice and snow will burn out all but a few films!

I have had best results with "traditional" films like Ilford FP4+, my one attempt at glaciers with Delta was a failure.

For extra effect try IR film...

Bruce M. Herman
6-Jun-2005, 01:07
John,

I work exclusively in color, so these remarks may be a bit off. I spend some time photographing glaciers here in Alaska and I'm primarily trying to address the color issue. You probably already know most of this, but perhaps it will focus your thinking when trying to decide what filters to take with you.

When you photograph the surface of a glacier during the day in a landscape context, the glacier more often than not appears white. This is because the recent snow that is found on the surface has not been greatly compressed. Being snow, it will reflect alpenglow at sunrise and sunset. Yes, it can be off-white on a cloudy day. To emphasize the glacier, I'd use a filter that darkens whatever is in visual contact with the glacier rather than lightening the glacier. I'd use exposure to get the right degree of white on the glacier itself.

Large pieces of glacial ice, or exposures of glacial ice along crevasses or in ice falls can appear white, blue or even a bit green. Smaller pieces can be nearly as clear as glass. Some of the photographs that I've made in serac fields have white or very light blue ice against a dark blue sky. Wouldn't this be a case where a polarizer would be a better choice for you than a blue filter? Other photographs in these same areas have been detail of the ice itself. In these, it's just ice, rock (usually black) and shadows. Here a blue filter might lighten the glacier relative to the shadows.

The point that I'm trying to make is that glacier photography isn't always about blue, and even when it is, it may not be something that you would want to exaggerate. I hope that this has been of some help to you.

Bruce

Brian Ellis
6-Jun-2005, 09:04
You need to decide what you want the print to look like and whether a filter might help achieve that look. Based on your description of the glacier I don't think there's a need to use any filter unless a polarizer would be useful to reduce glare (and a polarizer might or might not accomplish that depending on the angle of the sun).

In black and white photography colored filters are primarily used either to darken the sky when the exposure needed for the foregound would othewise cause the sky to be blown out or to create separation between two colors that otherwise would merge and appear to be same tone in the print (e.g. with a red apple against green leaves using a red filter to lighten the apple and darken the leaves or a green filter to lighten the leaves and darken the apple). I've never photographed glaciers so perhaps I'm wrong but from your description it doesn't sound like there are two different colors in the glacier that you need to separate (or could separate even if you wanted to) by use of a filter.

Assuming that the ice is predominantly blue a blue filter would simply tend to whiten the ice, which you could accomplish without the filter through your choice of exposure (open up a stop or two from the metered reading) or development time (develop the film for about 20% longer than normal ). A blue filter has a factor of 8x IIRC, or three stops, so using one would add quite a lot to your exposure time, which might kick in reciprocity adjustments, etc. etc. so adjusting the exposure or development time would IMHO be a better way of controlling the degree of "whiteness" in the ice than a blue filter.

Aaron van de Sande
6-Jun-2005, 09:57
I would forget about the filter and concentrate more on getting a good exposure. Depending on the amount of snow in the scene you will probably have to add a couple of stops to your shot. If you want to get the most out of your trip you may want to bring a polaroid back to do some tests.

Hans Berkhout
6-Jun-2005, 13:57
Interesting topic. I think you have to compare it to photographing large cumulus clouds; you'd probably use a 12 0r 15 filter.
You could argue against this by studying the works of Herbert Ponting, Frank Hurley, George and William Vaux, Vittorio Sella et al; likely using orthochromatic plates (blue sensitive), I don't know which filters they used if any, but separation in the highlights and cloud formations are very much present in their shots. No polarizers, uncoated lenses. Bradford Washburn used no.15 for clouds in his aerial ice/snow/glacier work. Look at Howard Bond's work and comments re shooting in the Swiss Alps.

I would shoot with and without filter and plan a follow up trip, learn from experience.

Ole Tjugen
6-Jun-2005, 14:08
I have no idea what filters and film Knud Knutsen used in 1872, but I'm sure it wasn't panchromatic film with a red filter - more likely wet plate?

www.ub.uib.no/bilder/sok/vis_stort_bilde.asp?ID=20229 (http://www.ub.uib.no/bilder/sok/vis_stort_bilde.asp?ID=20229)