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View Full Version : Motion Blur: Is there a detectable difference between leaf & Packard shutters?



Jay Decker
22-Jan-2011, 10:34
Started shooting LF with vintage soft focus barrel lenses mounted on old wooden cameras with Packard shutters about year and a half ago. Recently I've started to shoot with sharp focus lenses on these same cameras, e.g., 8x10 Kodak 2D and 8x10 Century studio camera. As a test, I shot the same sharp focus lens that is mounted in smooth running leaf shutter using the leaf shutter and using the Packard shutter mounted in my cameras. I had expected the there would be some detectable loss in sharpness between the negatives shot using the Packard shutter due to vibration, i.e., the Packard shutter operation would create vibration induced motion blur where the leaf shutter would create observably less. The result is that all of the images are sharp and I can not observe any difference in the images shot with the leaf shutter or the Packard shutter on either the field camera, an 8x10 Kodak 2D, or the studio camera, an 8x10 Century Universal.

Is this observation consistent with the experience of others?

Jim Galli
22-Jan-2011, 10:48
Is this observation consistent with the experience of others?

Consistent with mine Jay. It might be interesting to scientifically weigh the different moving parts and evaluate what the differences if any are for things moving up over things moving down. Do the 2 big bottom blades on the Packard that rotate as they fall act like the counter-balance on a crankshaft.

I make many soft focus images with Packards, but I also enjoy making the occasional tack sharp ones with them too.

Copal shutters are over-rated, but don't tell anyone. Barrel lenses are expensive enough.

Randy
27-Jan-2011, 18:49
I wonder if you taped a very thin gauge length (6" or 8") of wire to the front standard and watched for movement of it when you tripped each shutter. I would think if there is no movement of the wire there probably is no vibration of the camera at the time of shutter release.

Jay Decker
29-Jan-2011, 22:07
I wonder if you taped a very thin gauge length (6" or 8") of wire to the front standard and watched for movement of it when you tripped each shutter. I would think if there is no movement of the wire there probably is no vibration of the camera at the time of shutter release.

Randy - tried your idea tonight. I used a 3-foot long carbon fiber rod that is 0.040-inch diameter that I have in the shop and put a little piece of masking tape on the end as a flag to visually accentuate the vibration induced motion. Learned a couple things, 1) there was not a significant between a leaf shutter and a Packard shutter vibration, and 2) using a stabilizing arm from a tripod leg to the front rail of the camera reduced and dampened vibration.

Randy
30-Jan-2011, 19:44
Jay, so you DID see some vibration for each shutter trip? I guess I need to test my 8X10 now. I do not have any lenses with shutters. I mounted a Packard inside the front standard. With the amount of noise it makes when it opens you would think a bear just stepped in a trap.
I wonder if hanging a couple pounds of sand in a bag from the front of the camera would dampen vibration...?
Will see.

Jay Decker
30-Jan-2011, 20:12
Jay, so you DID see some vibration for each shutter trip? I guess I need to test my 8X10 now. I do not have any lenses with shutters. I mounted a Packard inside the front standard. With the amount of noise it makes when it opens you would think a bear just stepped in a trap.
I wonder if hanging a couple pounds of sand in a bag from the front of the camera would dampen vibration...?
Will see.

Yes, actuation of the leaf and Packard shutters resulted in vibration. It wasn't much, but the 3-foot long carbon fiber rod wiggled if there was any vibration. And, my Packard shutters are smooth running...

There are two fundamental ways to reduce vibration, 1) increase the mass of the system, e.g., your sand bag solution, or 2) increase the stiffness of the system, e.g., add a stabilizing arm, stiffen the camera frame, etc.

Scott Davis
30-Jan-2011, 20:56
The real test would be to do the same on the same camera - have a lens with a packard shutter on the 2-D and test it against the Copal-mounted lens also on the 2D. One thing that could be compensating for additional vibration that might be produced by the Packard is the mass of the Century studio camera. It takes a LOT to wiggle a Century.

Tracy Storer
30-Jan-2011, 21:17
And you can still buy Packard Shutters new. I recently ordered and received a brand new Packard with a 5" opening.
The owner, Reno Farinelli, is a good man to deal with. No BS.
http://www.packardshutter.com/

Jay Decker
30-Jan-2011, 21:20
The real test would be to do the same on the same camera - have a lens with a packard shutter on the 2-D and test it against the Copal-mounted lens also on the 2D. One thing that could be compensating for additional vibration that might be produced by the Packard is the mass of the Century studio camera. It takes a LOT to wiggle a Century.

Did four tests using the same lens that is mounted in a smooth running Copal leaf shutter: 1) leaf shutter actuation on the 2D, 2) Packard shutter actuation on the 2D, 3) leaf shutter actuation on Century studio camera, and 4) Packard shutter actuation on the Century studio camera. All four tests produced some wiggle at the end of carbon fiber rod clamped to the camera when the shutter was actuated. Yes, the Century was less than 2D, but even the Century studio camera was not dead still...

Michael Kadillak
30-Jan-2011, 21:54
And you can still buy Packard Shutters new. I recently ordered and received a brand new Packard with a 5" opening.
The owner, Reno Farinelli, is a good man to deal with. No BS.
http://www.packardshutter.com/

I got a new 3 3/4" opening Packard shutter from Reno as well a couple of weeks ago and am looking forward to using it. He told me that he is selling Packards to folks that are using them in other applications besides photography and his hard work is paying off for him. No BS is a great description as that was my impression as well.