Re: Paper Mounts for projection

[P3D Gregory J. Wageman <gjw@xxxxxxxxxx>]

Marvin Jones writes:

>I believe cardboard mounts are not recommended for projection for
>several reasons. First, aesthetic -- the edges are not as smoothly
>cut as aluminum mounts, and when projected, the roughness can really
>show up.

As with most things, is is more true of some mounts than others.  Of
the mounts from Reel 3D, it is certainly true of the slip-ins.  These
seem to be made of a particularly coarse grade of paper pulp and often
have long, thin strands of paper hanging off the cut edges.  They can
be really UGLY under magnification.  I have not had this problem with
the heat-seal mounts, though.  Obviously aluminum is the winner in
this department, as it never sheds.  The plastic RBT mounts are also
clean.

>Second, mechanical -- cardboard mounts don't hold the chips
>as firmly. They tend to buckle more easily when heated, and focus is
>much harder to hold. Also, cardboard mounts can be bent fairly easily
>by some changer mechanisms, and since they are placed in the projector
>"upside down," film chips have actually been known to slip out and
>fall into the projector.

It sounds like Marvin is mainly considering slip-ins here.  I mount
in the heat seals, using Wess tabs at the top and bottom of the
chips.  Once I've heat-sealed the mounts through a pouch laminating
machine, which applies a nice even pressure through several pairs of
springloaded rollers, the chips are very securely held.  There's no
danger of these chips falling out.  Though I don't project these
slides, I wouldn't hesitate to do so if I had the equipment.  I
personally would NOT use slip-ins for projection.

For projection, I use Gepe 2x2's with glass.  These completely prevent
the chip from "popping" (deforming under heat), as they can in commercial
cardboard photofinisher mounts, but modern Kodak projectors have a
"preheat" feature where the chip is exposed to heated air for several
positions before projection, and is thus allowed to "pop" if it's going
to before it enters the gate, so holding focus isn't usually an issue.
This obviously may not be true of a Realist-format projector and
slip-in mounts, though.

>And finally and most remote, safety -- cardboard mounts sometimes
>have tiny shards of semi-detached cardboard clinging to the apertures,
>and a hot projection lamp can singe and conceivably burn them, starting
>a chain reaction fire.

I agree this is "remote".  If you've got enough heat getting to the
mount to singe the paper shards, it's not going to be doing your
film chips any good, either!  However, I agree these shards could
be a problem when (not if!) they get into the mechanism, and they
tend to stick to the lenses and the chips due to static electricity,
further degrading the images.

Grant Campos writes:

>I admit I don't have experience in projecting slides.  But it seems 
>that when I've mounted my Nimslo chips in the slip-in mounts I can
>cut each chip a little narrower and end up with about 0.5 mm play (left 
>and right).  And, since they are slip-in there is plenty of adjust
>-ability up and down.  I then could use the Reel-3D little stickum 
>tabs to secure each chip.

>HOWZZATSOUND?                  

Personally I think too much adjustability vertically is a bad thing.
IF your camera takes properly registered images, AND the mounts are
properly made, you shouldn't need any vertical play.  Horizontal
adjustability of course gives you some freedom to adjust the window,
but vertically I just butt the top of the chips to the debossed tab
at the top of the aperture, and tape it down.

(I use the top because I've found from experience that the aperture
is closer to the top edge of the mount than the bottom, and if I don't
butt the chip to the top sometimes the sprocket holes are slightly
visible at the top edge of the aperture.  This may vary from batch
to batch, I don't know.)

This has always given me good vertical alignment.  Now, if you've got
a camera with a built-in alignment problem, this obviously won't cut
it for you.

        -Greg W.


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