Shutter Speed to Freeze the Breeze

[David Nash]

Hi

Over the last couple of weekends, I've taken my camera outdoors to take a few la ndscape shots. A few scenes have had long grasses in the foreground, and some h ave had trees somewhere in the picture.

In the past, I've always set the necessary f-stop to get sufficient depth of fie ld, trying to work within the 'optimum' range as recommended by the lens manufac turer (around f16-f22 normally). Using Kodak Tri-X that I rate at 100 ISO (for platinum printing), the shutter speed options tend to be fairly long in duration - maybe between half a second and a fifteenth - longer if it's within a dimly-l it building.

However, I notice that the grass can often be slightly blurred even if there is only a gentle breeze. The last shot I took, everything was calm while I set up, then the sun came out briefly and sent out a beautiful shaft of light - at the same time a breeze came from nowhere.... (Typical LF conditions).

My question is, what sort of shutter speeds should I be looking at to stop blurr ing of trees and grass in various levels of breeze? By the way, I live in Scotl and in the UK, and light levels on average tend to be quite a low.

Thanks in advance.

David Nash

[Jean-Marie Solichon]

Hi David I shoot mainly landscape and plants in the mountains of south France and I experience very often the same conditions as yours as far as wind is concerned. I probably have more available light than you have but use Velvia rated at 32 ISO. My feeling is that at 1/30s I am almost perfectly safe. At 1/15s I only need to wait for grass to slow down a bit. At 1/8s I need to become patient and wait that most of the vegetation stopped to move. At 1/4s and slower speeds I have to wait for "everything" being perfectly still. In some cases switching to E100S (rated at 80 ISO) have made the shot possible. Oh, by the way, a foreground of grass blurred by wind can make a much nicer shot than one with everything still/sharp!

[Robert A. Zeichner]

What shutter speed to use differs with different focal lengths and/or distance from the subject. What I might recommend is trying to do this early in the morning when solar activity hasn't yet had a chance to stir things up. Sometimes late in the day works too. I just made a 1 minute 10 second exposure of a Hemlock branch hanging over a little water fall and there wasn't a hint of movement in the Hemlock needles! I shot that subject after the sun had just about disappeared!

[Doremus Scudder]

David, I've spent hours waiting for things to "settle down" so I could make a long exposure without the breeze moving things around, sometimes in vain. Since I assume that you are using the fastest shutter speed possible for the image you wish to make in those conditions, I won't tell you to use a faster one. A couple of tricks might be helpful however. If there is only one swaying branch/twig, sometimes you can prop it a bit or tie it back to stop the movement. If the wind stops occasionally, but not long enough for your exposure (and assuming everything returns to its rest position) you can use intermittent exposures. I've made five minute exposures with no movement visible in groups of small exposures (5-30 seconds each), capping the lens whenever the least hint of wind starts up, and waiting it out. Somtimes it can take quite a while to get the whole exposure made. If your subject only moves occasionally, sometimes a really long exposure (20 minutes or more) will effectively stop the motion since the movement is such a small proportion of the total exposure time it becomes invisible. Sometimes you just have to give up! Regards, ;^D)

[David R Munson]

I don't know about you, but sometimes I rather like the effect created by the wind blowing the grass around during an exposure. Sure, it's kind of annoying when you try to take a picture of a nice big majestic tree against some beautiful horizon and have the wind blowing to a degree that instead of a tree you'll get a nice big majestic blurry blob, but wind-induced subject movement need not always be considered a bad thing. As for solving your problem, about all I can think of to suggest would be to maybe shoot your Tri-X at a little higher EI. It would give you faster shutter speeds, and since you're shooting LF, I don't think you'd really have to worry about a loss in image quality.

Just a thought...

[David_892]

Have you tried this method; instead of an exposure of say 1sec @f16, try twenty five at 1/25 sec @f16. It does freeze movement, and if conditions are just right it can also suggest movement slightly, even occasionally a slight 'kind of 3D' effect. I have tried this, and for the most part it worked well(around Fife anyway). Or there is an alternative, however you may not be happy with it - try a faster film such as HP5 for anywhere between 12 and 18 minutes, depending on your preference (and the conditions in which it was taken), in Ilfospeed print dev diluted 1-100. BTW I too live in Scotland and am quite happy using a more grainy film - as can be seen by my 35mm shots of Soulgreed at www.soulgreed.com/band.htm or /gigs.htm.

[William Marderness]

I wonder if you could rate the Tri-x higher than EI 100. I have not made platinum prints, but I have made POP prints, which are said to use the same type of negatives. I was told that POP prints needed dense negatives, 1 stop or more exposure than normal. I experimented with the paper using step-wedges and real pictures, and I found that the POP paper did not require any more exposure than what was required to get .10 negative density for zone I. The paper did require a lot more contrast, however. My normal EI for POP paper is actually 2/3 stop less than my normal EI for conventional paper, because the higher contrast required for POP (N-2 development) pushes up the EI of the film along with the contrast.

[William Marderness]

I meant N+2 development is normal for POP, not N-2. Sorry.

[josh_560]

Since wind is such a problem and small apetures a must why is the fastes film in sheets 400? Shooting 400 speed film and making very modest enlargements the grain is very fine i cant imagine it would increase that much with say tmax 3200 (rated at 800 or 1000).-J