[photo-3d] Re: Constant infinity mounting - II

[Paul Talbot <ptww@xxxxxxxxx>]

DrT wrote:

> If you are using RBT mounts you can very easily
> construct a tool that will allow you apply the
> constant infinity separation mounting method.  Here
> is how:
> 
> Your RBT mounts come with a little bag that contains the
> "rails" and a strange-looking yellow tool. Most people
> do not understand what this tool is for (neither do I!)
> But I have seen Ron Fross from our club modify this
> tool to apply a constant infinity mounting, which is
> the original intention of this tool.

I would point out that it is not really a "modification"
of the tool; that is how the infamous "little yellow
thingie" is designed to be used!  It is provided "too
big" so that you can trim it to the size required to
achieve constant infinity spacing mounting with your
particular camera.

[snip]

> I then cut
> the ends and trimmed then with a file so that this
> yellow tool FITS EXACTLY BETWEEN THE RBT RAILS.

> I have now created a tool that will allow me to space
> the rails to achieve a constant infinity separation.

"Created" is claiming a bit too much credit!  :-)  You've
managed (at this point) to use the the little yellow
thingie precisely as it was designed to be used.

> To finish the job I trimmed (with a file) the notch
> that makes the tool fit at the center of the mount

OK, you got me on that one!  I didn't know about the
notch.  The notch presumably allows one to set up a
whole batch of RBT mounts with both a constant infinity
and a constant cropping.  That's great for when you
want fast no-brainer mounting in premium-price mounts.  ;-)

When using a modified RBT mount as a jig for precision
mounting in affordable Spicer mounts, here's a tip to
save a step:  set up one jig with your basic center-crop,
normal infinity spacing (whatever that is for you), then
use a couple pieces of Delta One silver mylar tape to
hold the (sometimes slippery) pin bars in place.  A big
plus with this approach is you don't have to worry about
the pin bar staying with the film, instead of in the
channel in the RBT mount, after the film transfer.  (It
helps if your camera is pretty consistent with the
vertical alignment.)

Have a second jig handy for shots that require different
mounting than "standard spacing/standard cropping."  In
fact, it's quite helpful to have three or four "jigs."
For example, one with level verticals, two with .1mm
offset verticals (opposite directions), one with taped
down rails for quick and easy mounting.

Paul Talbot