Re: R lenses - ground glass screen, etc

[aglang@sprynet.com]

280/4.8 is a Visoflex lens, two versions differing by diaphragm location....

On Sun, 12 Oct 1997, Jim Brick <jim@brick.org> wrote:
>At 06:09 PM 10/12/97 -0700, you wrote:
>>
>>Also, many of the slides I took last month in Kodiak with the SL have a
>>camera shake problem. I used a 280 f4.8 Telyt, mounted on a Slik U8000
>>tripod - somewhat small for the SL/280 combo, but I always strapped my
>>camera bag over the tripod to weight things down. That approach worked
>>perfectly for my M6 long exposures in dark, emerald green forests. Those
>>slides are all very sharp. A couple of times with the SL, I could actually
>>see the front of the lens shudder when the mirror went up.
>>
>>I've shot B&W with the Telyt handheld at 1/500th or faster and have gotten
>>exceptionally sharp photos, so the lens does not seem to be the problem.
>>Has anyone had camera shake problems with the SL? Is there a mirror
>>movement or dampening mechanism on the SL that could be out of adjustment?
>>Any way to retrofit an SL with mirror lockup?
>>
>>Gary Todoroff
>
>Boy Gary... this one could take a long time. I went through this many many
>years ago. I can tell you that unless you do everything correctly, every
>time, the long lens shake gods will get you. Tripod or no tripod, if you
>shoot a 280 (where did you get a 280 f/4.8? I have a 350 4.8. Is it a 280
>2.8?) anyway, if you shoot a 280/350 at a shutter speed slower than 1/60th,
>even if bolted to a tripod, you stand a chance of shake. About ten years
>ago I invented a device called "Jim's Steady Hook". It mounts in the bottom
>of the center post of virtually any tripod. It's a stainless hook that you
>can hang a weight on. Your camera bag, a Steady Bag, a gallon jug of water,
>a bucket of dirt or water, anything. I carry a folding camping bucket
>(folds flat) and put rocks, dirt, water, whatever is available, in it when
>shooting long lenses. You can see a reference to my Steady Hook in Galen
>Rowell's book "Galen Rowell's Vision, The Art of Adventure Photography",
>page 81. Your camera is connected to one end of the center post. The center
>post is not actually part of the tripod. It is clamped in a single spot.
>Depending on your tripod, there can be a resonant vibration frequency
>through the center post. If you put a weight on the bottom of your center
>post, all vibrations inherent in the length of your center post, will be
>dampened. Putting a weight on the tripod itself is NOT the same. Your
>center post is still hanging out there.
>
>Next, I don't care which camera you have, a mirror hitting the top during
>an exposure, WILL cause vibration. Vibration on different cameras will
>occur at different times. My R3's and R4's were murder at 1/15 - 1/4. It
>depends where the shutter is in relation to the mirror at any given moment.
>At longer exposures (1/2 & greater) there's enough exposure around the
>vibration to not be noticeable. I had to move to an R6 with mirror lock-up
>(MLU) to eliminate the problem. I shoot a lot of Velvia + polarizer and
>sometimes an extender. This equals 1/2, 1/4, 1/8, 1/15 sec exposures most
>of the time, if you want any depth of field. I simply CANNOT shoot long
>lenses successfully without taking care of EACH and EVERY DETAIL. The two
>major helpers are a weighted center post and MLU.
>
>Next, if I shoot my 350 plus 2x extender (700mm) (and even sometimes
>without the extender), also with my 70-180 APO, I use a monopod under the
>camera. The lens mounts on the tripod. The camera hangs out the back. The
>camera is heavy and a vibration frequency could easily match internal
>camera mechanics (mirror, shutter, diaphragm mechanism, etc.) After
>composing and getting ready to shoot, I extend a monopod (I use a Bogen as
>the legs are easy to adjust) between the ground and the camera base. My
>personal setup is, I have a Leitz small ball head on the monopod with a
>Really Right Stuff (similar to Kirk) quick release platform. The bottom of
>my R7's winder has a RRS quick release plate. I connect the plate to the
>monopod (Leitz ball head is loose), adjust the monopod, then tighten up
>everything. Sounds like a lot of trouble but once you get used to it, it's
>really quick, and very very steady.
>
>Sound like a lot of trouble... well I'll tell you, traveling back to
>wherever you missed your shots due to camera/lens shake is more trouble.
>And a whole lot more expensive.
>
>A note. Art Wolfe uses a different technique. He's also usually shooting at
>1/30th or better. He doesn't use a cable release when using long lenses. He
>tightens up everything and puts pressure on the camera (pressure against
>the tripod head) which basically kills any free standing vibration. He
>releases the shutter with his finger, sort of gently leaning against the
>camera & tripod. This accomplishes the same thing but I find at shutter
>speeds below 1/30th, it doesn't work for me.
>
>I can't continue now, gotta go to bed,
>
>Jim
>