Recently got my Speed together and was noticing some significant vibration when the front standard is a ways out for close focusing. Have not had time to test using film yet, just wondering if anyone has experience with vibration causing loss of sharpness at various shutter speeds and bellows extensions, or suggestions on reducing vibration. Does the fact that the shutter is a horizontal curtain help to reduce visible effects? If I have a choice between tension 1 with a 3/4" curtain aperture for 1/40 sec or tension 6 with a 1 1/2" curtain aperture for 1/35 sec which would suffer more from vibration or would it make any difference?

Bobw,
Run some film thru it first, sounds as if the shutter may be adjusted to tight? There will always be some vibration, especially at the higher tensions, but it should not be of an consequence! And the higher the tension, the more vibration you would have, ...the shutter comes to a very hard and abrupt stop under all tensions..so logic would tell us that it will vibrate more at the hi end!
Have a nice day....Bert

Quote:

On 2006-02-23 13:23, bertsaunders wrote: Bobw, Run some film thru it first, sounds as if the shutter may be adjusted to tight? There will always be some vibration, especially at the higher tensions, but it should not be of an consequence! And the higher the tension, the more vibration you would have, ...the shutter comes to a very hard and abrupt stop under all tensions..so logic would tell us that it will vibrate more at the hi end! Have a nice day....Bert

Following up on Bert's hint, vibration that occurs after the exposure has finished has no effect on the image.

I AssUMe that you see the front standard shake a little when the Focal Plane Shutter is triped, so How tight is the front standard on the yoke? Does it lock solid or can you slide it on the yoke with a little pressure and the focus lock enguaged? If the lock tension is not set high enough the front standard will wiggle easily.
Look at the bottom of the front standard. With the lock in the unlocked/center position, loosen the lock nut 1/4 turn. Turn center screw counterclockwise a little (1 to 2 thicknesses of the screw slot) and hold in this position while tighting the lock nut. Test the front standard for movement when pushed on with focus lock enguaged. When tightned properly check for the vibration again.
Charles

A few factors could be causing your concern also. The Graphic as I think you have found out can become a bit shakey when racked out. A good sturdy tripod and head helps, but the mount is in the body. Also, any play in the foucussing track rails can play a part in this. And also as mentioned above, be sure all things at the front snug down properly includng the lens board and so forth, but the main problem I have found is the extension itself, and the combination of that and the weigth of the front standard. I recently ran a few tests with some heavy lenses like 210 f~4.5 tessars and used the FPS that had been reconditioned and ran smooth. But they are old technology and not what one would consider smooth like a modern 35mm FPS, and being a 5" wide curtain with a solid stop they will jump a little when released and hit hard when they stop. That said, I have been able to expose some images OK using the Time setting on both my RB and Speeds. Having a few of these to fix up now, some are smoother than others. The release mecahnism seems to play a part too and opperator camera shake when releasing is of course another factor. I prefer to trip the body release on the camera and actually steady the camera body when doing so as opposed to using an off camera cable release which showed noticeable shake. At fast speeds above 1/100 I wouldn't think nor have I had any problems, but at slower 1/30 and 1/60 speeds I find I have better hand held results using the front shutters and attribute camera shake at these speed to myself. Some people dont like fumbling around the front shutter to release, but I find the body release, at least in my case, brings on a little unwanted twist. On a solid tripod with my hand steadying the camera I certainly do not have this issue so long as the front standard doesn't shake. I will say this for some of the older slower longer lenses like the Ektar 203 and Optar, being smaller in thier #2 shutters, and therefore considerably lighter, camera shake is therfore considerably less. Regardless of any other factors however, Keeping camera movement to a minimum upon release should result in a reasonably good exposure, and any movement once the curtain aperture passes the film is inconsequincial.
So according to my limited experience with these cameras, the longer the extension and the heavier the lens, the greater the leverage placed on the drop bed, and thus the amount of instability will increase accordingly.
A camera that is rock solid with a 127 lens at infinity to 6ft will not necesarrily be so with a long extension for macros and or a big fast lens at 10" extension.
As suggested, test it at slow and fast speeds and you will note your limits using lens of choice and shutter, and depending later on how important getting the image is, make multiple exposures.

If you're shooting in horizontal mode, I've found that putting my hand on top of a tripod mounted camera and pressing hard, straight down, will help greatly to minimize the problem. If your shooting vertical frames, the momentum of the horizontally travelling shutter is a big problem. There's no easy way to fix that except using the heaviest, stiffest tripod you can find. Ball heads can be a problem, too, by giving more leverage above the tripod legs. Keep the center post down, too. Try hanging a gallon jug of water from the center post. Good luck.

The hand press will help also forthe verticle release. I think both hands create a more stable release than only having one on the camera body. If I am gonna touch the camera when exposing, I always use both hands. I have a lot of practice having to do so with light tripods in the backcountry. Though I have not tried it, I would think a long cable release might help with the FPS but I saw my cameras move so much with my standard long throw release I decided hand stabalizing would still be best in concert with good support.
I have thought about adding a plate for long focal lenth/long exposures between the camera and the tripod to help support the front better. This would reach from the back of the body to the front of the bed and while still mounting the standard body mount, the tripod would live about in the middle and the plate would be shimmed to support body and drop bed evenly as needed. I would think a 1/4" aluminum plate or G-10 sheet about 4" wide should do the trick with a tripod mount insert epoxied, or however one likes, in the plate. A helicoil would probably serve excellent in aluminum or G-10. The only thing to be careful of would be to make sure the plate does not misallign the drop bed and thereby alter the film plane, however, focuss would be checked on the GG. And this is pretty much why the older field and view cameras had multiple mounts and a big table plate on the tripod. One could also make this out of wood, perhps more easily, varnish it, and then add sticky back felt and have a nice light supplemental platform of old.

<font size=-1>[ This Message was edited by: troublemaker on 2006-02-25 17:56 ]</font>