Question for Kirk L-Plate users

[AdamJ]

I'm after a bit of advice about getting a new QR bracket that will properly fit the Kirk L-plate I got recently. I've illustrated the problem below but in simple terms, the base of the L-plate has a thicker (1.5mm) vertical rise than either of my current (Giotto's) Arca-Swiss-style QR brackets can properly accommodate, causing an offset that leaves the L-plate (and my camera) less securely attached than it should be. I have to say that it feels solid when locked down but I have doubts about how much of an accidental knock would dislodge it.



What I'm not clear about is whether it is the L-plate or my Giotto's QR brackets that are deviating from the Arca-Swiss standard. Must I get Kirk QR brackets or will I find that other makers' Arca-Swiss brackets are more generous in their accommodation than my Giotto's items? I don't think Kirk QR brackets are sold in the UK so I'd prefer a more widely available brand if possible.

Thanks for any advice.

Edit: I just re-read my post and in case of confusion, the 1.5mm height refers to the lowermost part of the L-bracket's base, below the 45 degree slope. That dimension is only 0.5mm on my Giotto's QR plates so they obviously fit with the Giotto's QR brackets perfectly.

[AdamJ]

I found an Arca-Swiss cross-compatibility table (linked below) which shows which brands work with which. You would think Arca-Swiss compatibility would imply a standard set of dimensions but... evidently not. So if I want my Kirk L-plate to be properly secured, I have to replace my Arca-Swiss QR clamps with different Arca-Swiss QR clamps. Great.

http://www.afximages.com/stuff/arca-plates-xref.html

[neuroanatomist]

Wimberley makes excellent clamps and there's a UK distributor (Bob Rigby).  As long as there's a decent overlap of the bevel, the connection should be secure. Even Kirk plate+clamp or Wimberley plate+clamp don't overlap all the way into the corners of the dovetail.

[Mt Spokane Photography]

I use Kirk Clamps and they have worked well with the various plates.  I bought a few when Kirk was selling them for $20 on ebay, but the price has jumped up.

[AdamJ]

Thanks to you both for your replies. I've since found an old thread on Fred Miranda addressing the very same issue. It seems as though Giotto's A-S clamps are known to have particularly shallow shoulders.

http://www.fredmiranda.com/forum/z/564313/0

Incidentally, Neuro, the degree of misfit is greater than my diagram suggests. It really is very marginal and if a leverage force were applied to the plate, I think it would only take a small yielding of the clamp's opening side to allow the plate to break free.

Kirk clamps would seem to be the natural solution, however the Wimberley C12 clamp is advertised as fitting the retaining lugs on the stems of, among others, Giotto's ball heads so I'll probably go with those. It's an expense I could do without but, you live and you learn.

[neuroanatomist]

...the Wimberley C12 clamp is advertised as fitting the retaining lugs on the stems of, among others, Giotto's ball heads so I'll probably go with those. It's an expense I could do without but, you live and you learn.

Indeed.  I started with the Manfrotto RC2 system before I 'learned'.    I have a couple of the Wimberley C-12 clamps and they work very well.  I've used them with plates from Wimberley, RRS, and Kirk, all clamp in securely.