jonjacobik Loc: Quincy, MA

I just purchased the Sigma 150-600 Contemporary lens with an MC-11 adapter to use on Sony A7R4. I sometimes use a gimble / tripod with an ARCA mount.
The Sigma has a single mounting screw socket. No matter how tight try to tight the D Ring mounting screw, it isn't long before the camera and lens start to slide - the lens foot against the ARCA plate.

I'm thinking perhaps a good epoxy would hold the mount plate to the lens, but haven't tried it yet. I'd rather have a less permanent solution.

And, did I mention, the little mounting plate and ring is just too small to carry the camera.

Any other suggestions?
Thanks.

Longshadow Loc: Audubon, PA, United States

A thin rubber gasket in the mounting ring? If that's what you are talking about.
(I don't know what type of adapter a MC-11 is. Does it go on the lens barrel?)

jonjacobik Loc: Quincy, MA

The ring itself doesn't slip. The slip is when the - lets call it the foot - that's used for mounting the lens to a tripod.
The lens foot - technically the tripod socket (Sigma calls that) slips against an arca mount.

The MC11 is a Canon / Sony E mount adaptor - that part works really well and the lens works quite well on A7r4.

Bill_de Loc: US

Are you sure the foot is Arca Swiss compatible? Many lenses do not come with one. There should be a dovetail cut along both edges.

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jonjacobik Loc: Quincy, MA

No arca groove, so the arca solution is a mount plate - and the has one screw hole on the foot. So with only point to fasten it, it spins.

Longshadow Loc: Audubon, PA, United States

The lens tripod mount turns on the ARCA plate?
Maybe a thin rubber gasket there? I don't know how they are built.
Hopefully the gasket will compress and eliminate the rotation.

Drbobcameraguy Loc: Eaton Ohio

You can get a long plate with rubber on it to attach to the sigma lens foot. It won't slip then. I use a sunfoto plate from adorma. It has 2 screws but I removed one I didn't need. If you are going to leave the plate on the foot apply a drop of locktite to the screw. I use orange because it's removable. The rubber on the plate prevents sliding the locktite prevents loosing of the screw. The long plate is nice so you can balance the setup a touch.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

I am going to suggest you not waste time with shims, washers, etc. Just purchase a quality lens Arca-Swiss plate - RRS, Kirk, Wimberley, Hejnar Photo - all make good plates. The main difference is that these use Allen bolts and MUCH better grip material on the plate - to keep things from moving around. The cheap plates have contact-cemented rubber pads that always come off, and the bolt is made of cheap metal and either has a slot that will allow the use of a screwdriver or a quarter, or in your case, the metal D-ring - I wouldn't use one of those.

Orphoto Loc: Oregon

The real key to a plate for a heavy lens is having a couple of small anti twist prongs that catch the edge of the lens' foot. The worst torque/slippage is when you go vertical. Don't forget to rotate the lens collar instead.

Manglesphoto Loc: 70 miles south of St.Louis

I just drilled and tapped a second 1/4-20 screw hole in the foot of my 150-600 Sigma Sport anything less will eventually fail. I wrapped the lens in a towel as a precaution just to be sure the chips from drilling and tapping didn't get into any part of the lens.

FiddleMaker Loc: Merrimac, MA

Gene, whenever you post something here it is always excellent advice. I really enjoy reading what you have to say.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Thanks!

I have lens plates from all of the mfgrs I mentioned, and a couple of cheap knockoff plates from Benro, Sirui and others - so I speak from experience. A rubber washer is just going to decrease the contact area between the plate and the lens foot, so its only point of contract is the circumference of the screw, which is exactly the opposite of what is needed. Also, the depth of the thread becomes an issue with some knockoff plates - if the thread is already pretty short, adding a washer is going to mean less thread engagement in the tripod foot, another thing that is not desirable.

FWIW, I have a Sigma Sport 150-600, and I did not have to resort to drilling a second hole - while I seldom use it on a tripod - mostly for moon shots, landscapes and distant waterfalls with longer exposures - I have not had a problem in 5 yrs of ownership. The single tripod socket is all that is needed when you use quality plates. I wouldn't dare use the cheap plates, which spin even with a 2.5 lb bridge camera.

FiddleMaker Loc: Merrimac, MA

Gene, I have the Tamron 150-600 G2 for my D750 but I have used it only 3 or 4 times in 3 years due to a severe case of spinal stenosis and arthritis in my hands (I am closing in on 80 yrs old).

I recently saw a YouTube video by Hudson Henry on the advantages of a fluid head instead of a ball head or gimbal setup. I have a Manfrotto carbon fiber tripod (MT190CXPRO3) but I think I would need a heavier model if I were to consider a Manfrotto fluid head that would be suitable for the D750 and the Tamron 150-600. I also have a very heavy Ravelli tripod but that thing is a beast. But I do use the Ravelli when I use the Tmrn 150-600 and a real sub-standard gimbal (ProMaster) that I got talked into when I bought the Tamron 150-600. But a fluid head (that the video folks use) might entice me to get out and use the large tele lens. Hudson Henry points out that these fluid heads are excellent for still photography as well as video.
The Manfrotto MT190CXPRO3 is fine for my D750 with a smaller lens or my small Fujifilm X-T2 but it may be too small for anything larger. Just my thot.

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

When I had a similar problem I used a rubber sheet cut to size.

imagemeister Loc: mid east Florida

I usually remove the small d-ring screw and relpace it with a stainless Phillips head screw and lock washer and tighten it with a large screwdriver......It is best to use a 100mm A/S plate that will afford maximum contact area.....and also allow maximum range for balance adjustment.

Due to the highly compromised tripod collar, I use and recommend a long lens stabilizer bracket with any of the big zooms and even some of the longer primes - https://www.ebay.com/itm/Neewer-Telephoto-Lens-Support-Bracket-Quick-Shoe-Plate-Long-Focus-Stand-Holder/383265116178?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20201210111314%26meid%3D452e574cfc4f445fa253e4d015682cd6%26pid%3D101195%26rk%3D1%26rkt%3D12%26mehot%3Dco%26sd%3D283448072618%26itm%3D383265116178%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv9PairwiseUnbiasedWeb%26brand%3DNeewer&_trksid=p2047675.c101195.m1851

No problems with "cheap" plates in my world -IF- properly used.
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