The benefits of longer exposures?

[Mahler_one]

As a relative newcomer to LF photography I have been using the galleries of our talented members as a learning tool. While pursuing such efforts I have noted that a good many exposures of static subjects ( walls, fields, fences ) have been made with exposures in the many "seconds to minutes" range. I do understand that such exposures would be useful to blur water, leaves, etc. for creative effect. However, I don't quite appreciate the benefits of longer exposures when the subjects are static objects. Such exposures appear to be longer then would be indicated and necessary by the speed of the film used, the needed depth of field, and the lighting present ( of course, I don't know such facts with assurity ). Hence, I'm asking if the experienced photographers here might tell me the benefits of several minutes exposure when shorter exposure(s) might suffice. Are the longer exposures beneficial for shadow and texture detail(s), and if so, how does one correct for the possible over exposure of the highlights? One also must correct for reciprocity, and one obviously must be very much aware of the wind and the stability of the camera and tripod. The intuitive approach of a novice as myself would be to use the shorter exposure rather then contend with the issues noted.

Thanks.

Edwin

 

[Nick Zentena]

If you don't have a shutter then long exposures are useful.

Other then that for ULF formats when you might be at F/64 or smaller with film that might be 100 ASA [and slower EIs] even sunny days end up dark.

Or you might be using something like the Freestyle Lith film with a film speed closer to that of paper then most film

 

[David A. Goldfarb]

If you're using a slower traditional (not T-max) film, small aperture, filter, and then add bellows factor and reciprocity, and then maybe you use a developer that reduces effective film speed, it can add up. The larger the format, the sooner you'll be in bellows factor territory, which can push you into reciprocity territory.

 

[Paul]

I think the largest shock I had when starting large format (8x10) was how often the shutter speeds end up being very slow out of necessity. 1/8 of a second seems fast and I use 400 speed film.

 

[DannL]

Edwin, could you point us to several of these photographs in question? Every situation is unique.

Dann

 

[Mahler_one]

DannL....Ok....I will try to find some specific examples, and ask the permission of the photographer if I can reference the work on this specific thread.

I very much appreicate the useful comments made thus far....and yes David, as far as I recall, the film was slow speed Efke with longer lenses....I don't recall the developer.

Edwin

 

[Ian Grant]

Here's a couple of quite different examples:

and

The first is just long enough to show movement of the water, but not too long or all the sea would fluid . . 1/4 sec

The second, apologies for the poor scan, is a long exposure made up of fragments, so overall 8 seconds, made up of multiple exposures 1 sec, 1/2, 1/4, etc, this stops the movement in the trees & grass from just being a blur. The print is approx 24"x30" and some of the grass plus the brick work is very sharp.

Ian

 

[MurrayMinchin]

I like longer exposures (usually around 1.5 minutes) in the dark temperate rain forest I photograph, but don't reduce development as would normally be the case. There are no really high values in the forest so there aren't any highlights to be blown out, but the middle and slightly higher values effectively get + development, which adds texture.

Murray

 

[Ian Grant]

There are no really high values in the forest so there aren't any highlights to be blown out, but the middle and slightly higher values effectively get + development, which adds texture.

Murray

What no snow scenes then

Ian

 

[MurrayMinchin]

What no snow scenes then

We've had snow on the ground for 4 months...only 2 months to go until it melts

Actually, somewhat longer exposures without development compensation work on snowy forest scenes too, because it's rarely sunny here. No annoying bleached out hot spots, just the softest diffuse light from the many thousands of square kilometers soft box (thick clouds) overhead

Murray

 

[JBrunner]

Most of my long-ish exposures of still life are because of needing to carry focus. When you factor in all of the other things David mentioned earlier, you wind up with a long exposure on something that doesn't move. It's not really something done for benefit, but rather an artifact of other considerations.

Temporal distortions for effect are another matter.

 

[Jim Noel]

Long exposures are an easy way to build contrast for salt and albumen prints in films which don't expand enoughl in the developer. ie. Most 400 speed films.

 

[Rich Ullsmith]

At dinner one night with a platinum-printer friend of mine, he was drawing exposure and density curves on the napkins and trying to explain why "reciprocity can be your friend." He was adamant. I don't remember a thing about it, but after reading this thread I'll go talk with him again about it, without a head full of wine.

 

[Bruce Osgood]

If you're using a slower traditional (not T-max) film, small aperture, filter, and then add bellows factor and reciprocity, and then maybe you use a developer that reduces effective film speed, it can add up. The larger the format, the sooner you'll be in bellows factor territory, which can push you into reciprocity territory.

David,
Why do you exclude TMax from this? I've just begun using Tmax and want to avoid as many pitfalls as possible.

 

[David A. Goldfarb]

David,
Why do you exclude TMax from this? I've just begun using Tmax and want to avoid as many pitfalls as possible.

T-max has better reciprocity characteristics than traditional films like Efke, Foma, Tri-X, FP-4+, HP-5+, etc., so you don't end up in long exposure land as quickly. For long exposures, TMX becomes a faster film than Tri-X.

 

[Bruce Osgood]

I see what you're saying now. Thanks,

 

[Ian Grant]

Tmax is amazing in very low light conditions, it's outstanding and very tonal.

Ian

 

[keithwms]

I think the main benefits of long exposures are compositional in nature.

Also, nothing clears a scene of pedestrians as well as a long exposure! Well, maybe a stink bomb....

 

[panastasia]

Another benefit of long exposures would be the ability to illuminate a large object at night w/portable flash or a continuous light source, while the shutter is open.

Paul

 

[DannL]

Capturing asteroids (space debris and rocket bodies) entering the atmosphere can be a real nightmare without long exposures.

 

[CBG]

David Goldfarb's comment is spot on. Say you are using a 125 asa film - an old style film like Plus X. The sunny sixteen rule says on a bright sunny day, you'll be at 125th sec at f16, or more likely if you're working with a LF camera, a smaller stop: maybe 1/30th at f32.

But, hold it, the weather's dark and moody. Add four stops to compensate for a dark cloudy day: so now you're at 8th at f32.

You're shooting with a #21 orange fiter. Add filter factor of 4x: now you're at 1/2 sec at f32

Your 8" lens is cranked out to 11" to focus moderately close and you're at a bellows extension factor of 2x and that gets you to one second at f32.

Your subject is quite dark, so you elect to bump up the exposure to two seconds.

You calculate for recprocity failure last. Reciprocity failure for an old style film like Plus X means it will take five seconds to achieve what you calculated would take two seconds. So you are shooting five seconds at f32 in the middle of the day.

Best.

C

 

[Bruce Osgood]

SNIP
Also, nothing clears a scene of pedestrians as well as a long exposure! Well, maybe a stink bomb....

My first 'long exposure' was nearly one minute and a husband, wife, baby and carrage walked right thru it. I took a second and developed the first with the second and there was no evidence of their passing by.