Rails with scale like RRS MPR-192?
/forum/topic/829115/1

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Drew_Persson
Registered: Oct 25, 2006
Total Posts: 1205
Country: United States

E-Vener wrote:
Positive. bars are lighter than the RRS bars -- same ideas but different. Definitely not knock-off clones as I feared.

Clamps work well. So far everything seems solidly constructed. Best match to actual Arca-Swiss clamp bevel angles and width of the various (Acra-tech, Kirk, Foba, Novaflex, Graf, RRS) clamps and plates I own. No problems mating with any of the above (except for the clamp I salvaged from a Graf Studioball).

Waiting for one of their panning clamps.


Are you suggesting the bevel angles aren't all the same? I assumed there's a standard angle that all the manufacturers follow, seems crazy that any of them would deviate from it.



E-Vener
Registered: Jun 18, 2009
Total Posts: 4260
Country: United States

Drew,

I am not suggesting it. I am reporting what I've seen using a mix of clamps and plates from various manufacturers. If you check RRS they'll tell you the same thing, as will Arca-Swiss.

In the real world I haven't found it to be such a big deal as long as the clamp makes pretty substantial and solid contact with the 'foot" on the plate along the length of the plate. The basic Arca-Swiss design is over engineered for DSLR and medium and small format cameras as it was orginally designed to support 8x10 view cameras where you can apply a lot of imbalanced pressure on one end simply by inserting and removing film holders especially if you have a lot of extension. The comparison would be using large aperture super telephotos on a DSLR where the front end is really heavy.

The problem comes if you use a lever type clamp when a manufacturer makes a "foot" that is wider or narrower than the clamping mechanism. With screw tightened clamps it's only a problem if the "foot" is narrower than the clamp.

My general rule conclusion is that if you want assurance that you absolutely have the best fit get plates from the company that makes your clamps.



Drew_Persson
Registered: Oct 25, 2006
Total Posts: 1205
Country: United States

Ah, I expected slight width variations across manufacturers (which isn't good for the lever clamps), but assumed the angle of the dovetails would be consistent, since that's a pretty easy thing to set on the machine.



E-Vener
Registered: Jun 18, 2009
Total Posts: 4260
Country: United States

You'd have to ask the different makers why they do that. probably thought they were improving the wheel. Different width is a more serious flaw than differing bevel angle. I have a generic Novaflex L bracket which I really like but for the RRS screw drive clamps on a PCL-1 and their MPR-CL II "nodal slide" to lock down tight on it I need to add a paper shim the thickness of a standard business card.



hejnarphoto
Registered: Sep 12, 2009
Total Posts: 49
Country: United States

Hello everybody
It is old post but i want let you know that i do make a rails with laser engraved scale


This image is copyrighted by the owner




Drew_Persson
Registered: Oct 25, 2006
Total Posts: 1205
Country: United States

Nice Chris, wish you had those when I got my 12" rail from you. Maybe sometime I'll sell it and get one with the scale.



hejnarphoto
Registered: Sep 12, 2009
Total Posts: 49
Country: United States

Drew
Next time i will have something for engraving you can send me yours and i will make nice metric scale on it. It will cost you only shipping 2 ways



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