Arca-Swiss foot for the S2? (1 Viewer)

[fazalmajid]

I have the S2 82 HD with 30-60x eyepiece. I'd like to replace the Manfrotto-type foot with an Arca-Swiss style QR plate, ideally replacing the Manfrotto altogether so I can use my photo tripods, failing that an Arca dovetail that attaches with two screws to the Manfrotto foot so it can't twist.

Has anyone on the forum had success doing this?

I noticed they introduced a S2 rail accessory. It's unclear what kind of dovetail this has. Does anyone know?

 

[Tringa45]

I suspect the rail assembly is intended to balance the scope if used with a camera for digiscoping.
However, it would appear that the scope foot accepts an anti-rotation pin in addition to the 1/4"x20 screw, so any Arca-Swiss plate with this would work.
Bear in mind though that it is advisable to use a plate from the same manufacturer as the head. Although just about any A-S plate can be retained by any A-S head, not all safety retention systems are compatible from one manufacturer to another, so a loosened clamp could allow the scope to fall out!

John

 

[fazalmajid]

I'm starting to wonder if I should prototype one on a 3D printer and then have it fabricated in aluminium, which should only cost about $50-100 or so.

 

[Tringa45]

I'm starting to wonder if I should prototype one on a 3D printer and then have it fabricated in aluminium, which should only cost about $50-100 or so.

Obviously a problem of enormous complexity, which has involved a month of brainstorming! :storm:
An original Arca-Swiss plate of suitable length can be obtained for the price you mention, one of Chinese manufacture for about §15.

John

 

[fazalmajid]

Obviously a problem of enormous complexity, which has involved a month of brainstorming! :storm:

Well, Birdforum doesn't have reply notifications...

I looked at the collar ring again, it looks like the Manfrotto foot is an integral part of the ring and not removable.

An original Arca-Swiss plate of suitable length can be obtained for the price you mention, one of Chinese manufacture for about §15.

The challenge is finding a plate with anti-twist pin that fits in one of the 4 holes provided. I am going to try my luck with this one:

http://www.hejnarphotostore.com/product-p/d016.htm

as I've had good experiences with the brand before, and it is much cheaper than the Kirk equivalent:

https://www.kirkphoto.com/camera-mo...amcorder-plate/universal-camcorder-plate.html

(RRS also has one, but the mounting screw to pin distance is not adjustable)

 

[Tringa45]

I assume both those plates are Arca-Swiss compatible but the fixed anti-rotation pins do look suspiciously large.
Usually they are 4,5 mm dia. and removable, though my Swarovski scope accepts 5,0 mm.
As already mentioned, safety retention could be a problem but this plate: https://www.kirkphoto.com/lens-moun.../universal-multi-purpose-lens-plate-4-50.html has screws to attach underneath as safety stops and the lip will perform the same duty as an anti-rotation pin.
The lip could aso be repositioned to allow fore and aft movement to balance out the scope.
You could, of course choose one of the shorter plates but I would willingly accept the 50 g weight penalty and the extra 2 dollars for the greater adaptability.

John

 

[Alexis Powell]

That Kirk plate should be good. If one doesn't need a sliding plate, the generic Kirk PZ-17 plate, or equivalents from RRS like the current BP-CS or the old BP-21, with lip works on everything I've used it with.

https://www.kirkphoto.com/universal-camera-plate-pz-3385.html

For a cheaper alternative, as well as sliding ability, I've found that the Desmond plates with lips work perfectly with my scopes. These are the ones that are my first (and usually last) recommendation to anyone looking for a nonrotating plate for a scope or long lens. They are really good and really cheap, and they come in several lengths depending on how much sliding you want to do.

https://www.bhphotovideo.com/c/product/1062504-REG/desmond_dpl_100_3_9_long_lens.html


--AP

 

[fazalmajid]

An update: I ordered the Hejnar Photo plate I linked to above, but haven't received it yet. If it doesn't work out (pin too large, or pin too small and not providing sufficiently tight anti-rotation) I will try the Kirk one next, as I have had good experiences with both vendors (also Acratech, Markins and ReallyRightStuff).

I do have some plates for long-gone cameras with lips like the Desmonds Alexis mentions. I'm a bit more wary about that solution because unlike a pin and sliding bolt, the geometry does not enforce anti-rotation (the bolt can slide and loosen the contact with the lip if sufficient force is applied), but that's a good plan C.

 

[Tringa45]

An update: I ordered the Hejnar Photo plate I linked to above, but haven't received it yet. If it doesn't work out (pin too large, or pin too small and not providing sufficiently tight anti-rotation) I will try the Kirk one next, as I have had good experiences with both vendors (also Acratech, Markins and ReallyRightStuff).

I do have some plates for long-gone cameras with lips like the Desmonds Alexis mentions. I'm a bit more wary about that solution because unlike a pin and sliding bolt, the geometry does not enforce anti-rotation (the bolt can slide and loosen the contact with the lip if sufficient force is applied), but that's a good plan C.

I think your worries about the anti-rotation lip are ill-founded. The radial and tangential loads on automobile wheels are transmitted by friction between the wheel and hub and not by sheer loads on the bolts or studs.

Even if the fixing bolt loosened, it wouldn't result in a catastrophe. However, if the clamp on the video head loosened, it very well might! My concern is that that Hejnar clamp is too short to enable you to extend the safety stopper screws on the underside.

John

 

[fazalmajid]

Even if the fixing bolt loosened, it wouldn't result in a catastrophe. However, if the clamp on the video head loosened, it very well might! My concern is that that Hejnar clamp is too short to enable you to extend the safety stopper screws on the underside.

Yes, your points on the slide-stop bolts feature on the Kirk are well-taken, unfortunately I had already ordered the Hejnar by the time you posted.

 

[fazalmajid]

OK, so I finally received the Hejnar plate, after seemingly interminable customs clearance time.

I measured with calipers, the plate pin has 4.72mm diameter, whereas the holes in the scope collar base are 4.79–4.82mm, so a good snug fit. There is still some rotation because the bolt in the slot has some slop in the direction perpendicular to the slot axis, but it disappears after tightening.

My tripod ball head doesn't have the anti-slippage slots/cutouts for the two small retaining bolts, but my PreMediaGear Katana Jr gimbal does (FWIW, the vertical adjustment is 67mm) and I verified they work as designed when the Arca clamp is loosened. Of course, the Meopta tripod collar is aligned with the scope center of gravity, so the fact the anti-slip pins are fairly narrow because of the small size of the plate is not an issue as there is no Y axis adjustment necessary.

All in all, I am very happy with this solution. Thanks you all for your advice and encouragement!

 

[Tringa45]

Thanks for the feedback. Glad to see everything functions as it should.

John