Hi,
Wanting greater ease and precision in leveling my tripod head, I recently purchased an Arca D4 head then decided to do a very unscientific comparison between the D4, my Gitzo 1570, and my Markins Q20 for vibration resistance.
Here's the set up:
The tests were shot in my studio which has a 6" concrete, radiant heated slab floor. I used a Gitzo 5530, 6x carbon tripod with 2 leg sections, no column, and a Markins circular tripod mounting plate. I used a Mamiya AFD camera (5.5 lbs. with lens and DM56 back) and an Arca 6x9 (7 lbs. with lens and DM56 back).
With the 6x9, I placed a petrie dish on the top the camera partially filled with water that would vibrate anytime I touched the camera or rail, push the cable release, or stomped on the floor (mild stomp). And, here's the real scientific part, I would time how long it took the water in the petrie dish to become completely still after inducing vibration. I know tapping the rail, or pushing the cable release, or stomping on the floor to induce vibration sounds really silly because the force generated by each attempt would have to be different each time, but to my surprise I got fairly consistent results when say I stomped on the floor three different times or flicked the rail three different times. (I can't believe I am writing this!)
With the AFD using an electronic cable release and a test target small in the center of the frame, I took several exposures using manual focus checking for sharpness at 100% each time until I got the sharpest focus possible for each tripod head set up. I placed the petrie dish on top of the camera (balanced on the hot shoe) and took exposures once the water in the petrie dish was completely still at 1/2 second and 1.5 seconds (I put ND over the the light) with the mirror locked up and the mirror not locked up to create a source of vibration. I cropped a portion of the test target from each image viewed at 100%, then cut and paste them into a new document to compare side by side.
Here are the results:
With the 6x9, the Arca D4 and the Markins Q20 heads performed the same. Whether I stomped the floor or released the shutter, it took about 4-5 seconds for the water to become completely still. When I tilted the camera over 25 degrees, it still took 4-5 seconds for the water to become completely still after inducing vibration. The large Gitzo head consistently took about 8-10 seconds for the water to become completely still, whether level or tilted 25 degrees. On the other hand, when I forcefully tried to torque the camera rail up, the Gitzo head clearly provided the stiffest connection to the tripod, the Markins a close second, and the D4 a somewhat distant third.
With the AFD, using the D4 resulted in sharper images than the Gitzo when the mirror was not locked up at both 1/2 and 1.5 second exposures. (I didn't test the Markins because it had matched the D4 when tested with the 6x9.) The difference in sharpness was slight at the 1/2 second exposure but clearly noticeable at the 1.5 second exposure. With the mirror locked up, I could see little difference in sharpness at either exposure for each tripod head.
One surprise to me was that my more expensive, 20", plastic coated cable releases always induced vibration in the water as I depressed the plunger, so I am going back to using more flexible, fabric coated, cheaper cable releases. The Mamiya electronic cable release induced no vibration in the water.
I am pleased with the performance of the D4 in my tests, though with a much heavier load it may not perform as well. The D4 is a pleasure to use compared to the Gitzo or Markins for leveling and making precise movements. The thing I wonder about is how it would compare to the C1 with a camera tilted 25 - 45 degrees? The D4 has the same amount of bearing or clamping surface whether level or tilted, and the C1 seems to have about 1/3 the amount of bearing or clamping surface when tilted that much. Any comments from C1 users?
Hope this provides some useful information.
Drew Harty
