A question for Bjørn...

[CS]

But others are encouraged to respond too.

Not long ago, I remarked about a friend of mine going to Oregon next moth to capture the upcoming eclipse of the Sun. He's using 4 camera setups, but this is about one of them, his D7200/80-400 (first model) mounted on a tracking device arm. He's having vibration issues, says that the tracker is vibration free, so it looks like they are all from the shutter, through that lousy tripod collar.

I referred him to your Tripod Collar Blues article from 2002. Then I though I'd ask you if you had any specific advice for that setup with the 80-400 hung out there in outer space? I'm including an image of his setup in case it helps.

[Akira]

Wow, the collar is the weakest link in the true sense of the word in the setup...

[CS]

I forgot to add that he will be hanging about 10 lbs of weight on the tripod to aid stability which he says is rock solid to begin with.

[CS]

Wow, the collar is the weakest link in the true sense of the word in the setup...

Absolutely! OTOH, he is doing what he can to make the best of the situation. I measured the diameter of an asthma inhaler, 13/16ths, in case that dimension works (wrapped with foam, of course) for his 80--400. 

[Bjørn Rørslett]

Not even hanging 100 kg of stone under the tripod would help in the slightest. The weak point is glaringly obvious: the tripod collar of the lens. The added lateral leverage just makes the situation worse.

An additional support for the camera or lens is urgently required. A simple approach would be to drop the flimsy tripod collar entirely and use gaffa tape (or straps?)  to fasten the lens directly to the tracker. First put a longer plate on the tracker head to provide a better mounting surface.

[CS]

Not even hanging 100 kg of stone under the tripod would help in the slightest. The weak point is glaringly obvious: the tripod collar of the lens. The added lateral leverage just makes the situation worse.

An additional support for the camera or lens is urgently required. A simple approach would be to drop the flimsy tripod collar entirely and use gaffa tape (or straps?)  to fasten the lens directly to the tracker. First put a longer plate on the tracker head to provide a better mounting surface.

Thanks. Bjørn, I'll pass your info on to my friend. He's doing a lot of testing now in order to be ready for the event, and I'm sure that he will be glad for the help. 

[Frank Fremerey]

A screw on industrial clamp should do for the moment. Put some insulation between the lens tube and the clamp

[CS]

A screw on industrial clamp should do for the moment. Put some insulation between the lens tube and the clamp

Thanks, Frank, sounds like a good suggestion.

[David H. Hartman]

I would make a lens cradle to hold both the lens and camera together on one plate of tempered aluminum as one unit. The fit needs to be perfect so the lens and camera are not under stress when it's all tightened down. I'd secure this to the bottom of the lens cradle with two screws and maybe JB Weld Wimberley P30 Quick Release Plate. The lens collar would probably be made of a couple of pieces of bar stock. I'd screw and JB Weld them together. You'll want as few surfaces a possible where there is any play, even minute. 

I'd use a Wimberley C-30 Quick Release Clamp on the plate added to the tracker. I'd secure the C-30 with two screws. It's more money but I'd use a RRS or Kirk L-Plate on the camera. The L-plate cradles the body so there isn't only a small rubber cushioned contact area. I would probably secure the camera L-plate and lens tripod collar directly to the lens cradle. I'd use a plate on the tracker head with two screws into the C-30 clamp. I'd use a safety stops and a safety cable.

Does anyone make a replacement lens collar for the lens. The lens collar looks terribly weak. I'd rather start with a better collar if possible.

I've thrown this down rather quickly as Ideas I'd start with. I have to run.

Dave Hartman

Below is an example of a lens cradle. The aluminum blocks are held together with four screws and JB Weld to be double sure of the integrity of the unit. To assure a good bond I cleaned the parts with acetone before assembling. If the unit with the PN-11 were to fail with a 105/4.0 AI, PN-11 and dSLR all would hit the ground. It would be nice to have a machine shop and skills to mill the unit out of one block of aluminum.

[Øivind Tøien]

When I point my 300mm PF high in the sky on my tracker, I do not use the tripod collar at all (even if it is pretty decent), I just use the plate on the camera. That gives better balance. I am not sure if angle of the sun is high enough for the eclipse though. The suggestion with dual attachment point to the camera plate and the collar sounds like a good one. For high alt. angles, one would want to bring the attachment point towards the body away from the lens collar.

[Bill De Jager]

In Oregon, the angle of the sun above the horizon at the time of totality will vary from 40 degrees at the coast to 45 degrees at the Idaho border.  This will continue to increase eastward, up to about 61 degrees when the umbra reaches the Atlantic Ocean.

[pluton]

A possible alternative solution is to replace the SLR with a mirrorless camera.  But...I have not used the lens in question.  If the tripod mount collar of that lens is really bad, mirrorless may not help.
Example: If I use my 300/4 AF-s(fitted with Kirk aftermarket tripod mount collar) and a D800 + small Gitzo CF tripod w/RRS BH-55 head, I dependably get ruined images via  camera shake at the "danger zone" shutter speeds.  If I swap out the D800, and instead use the same lens and setup with the lowly Fujifilm XE-1(on Novoflex FUX-NIK adapter), the camera-induced shake is gone. 

[Bruno Schroder]

I would buy a long Arca compatible rail, 300 or 400mm, fix it on camera and carve 1 or 2 pieces of wood to support the lens, screw them to the rail and apply large amount of gaffa tape everywhere possible. These rails do have many holes for screwing and additional rigidity can easily be gained by screwing 2 rails together or by screwing additional metal plates to the rail.

[Frank Fremerey]

I see CS, your call gets the creative juices flowing.

[pluton]

I would buy a long Arca compatible rail, 300 or 400mm, fix it on camera and carve 1 or 2 pieces of wood to support the lens, screw them to the rail and apply large amount of gaffa tape everywhere possible. These rails do have many holes for screwing and additional rigidity can easily be gained by screwing 2 rails together or by screwing additional metal plates to the rail.

This is a promising idea that isn't highly expensive.