Material for Custom-Made Darkslides ?

[Ken Lee]

I would like to make a set of dark slides of various ratios, such as 1:2, 3:4, etc.

One option is to cut up an existing dark slide - but that can be a waste of a good dark slide.

If I wanted to get some material that is rigid, opaque, and of the appropriate thickness - and which I could cut to shape with a simple blade - what would I buy, and where could I get it ?

The final items don't have to have nice handles and locks. As long as they can inserted and removed, they are good enough.

[Kirk Gittings]

I have made great ones from brass sheets from a hobby shop. As a cutout though they may reflect some light.

[JasonC]

Phenolic sheets will work. Vulcanized fiber paper (fish paper) and Delrin should also work.

[GPS]

You might find posts about it in the archive. Various plastic covers available in paper shops can be used - they are semi rigid, black, easy to cut, cheap. Not so rigid as metal ones but usable.

[Oren Grad]

Great question! Alan Brubaker (http://www.filmholders.com/filmho1.html) says he uses "phenolic plastic" - perhaps he'd be willing to identify a specific product or supplier.

[Harold_4074]

McMaster-Carr sells black phenolic/paper stock a Grade XX Garolite (stock numbers starting at 85315K411) which I have used to make a set of dark slides with holes for making zone-system calibrations on single sheets of film. The material can be worked with metalworking or woodworking tools, as long as they are sharp--it is prone to chipping at the edges. Smoothing the edges well will prevent damage to the velvet in the holder's light trap, and a coat of hard paste wax afterwards is also a good idea.

McMaster-Carr: http://www.mcmaster.com/

[Ken Lee]

The material can be worked with metalworking or woodworking tools, as long as they are sharp--it is prone to chipping at the edges.

I once bought a 4x10 dark slide from Bender, and decided to cut it down further, so as to achieve a different ratio. It was a "real" dark slide (Fidelity ?), and was soft enough to cut with a sharp blade, and smooth with some sandpaper/steel wool.

That is around the limit of my tool set.

[Ken Lee]

Great question! Alan Brubaker (http://www.filmholders.com/filmho1.html) says he uses "phenolic plastic" - perhaps he'd be willing to identify a specific product or supplier.

According to his site, "The septem material is a: .040" black anodized aluminum plate, or .060"or .080" phenolic plastic plate."

...Is a "septum" the same thing as a "dark slide" ?

[Glenn Thoreson]

Metalsonline.com has some aluminumm in something like 6X10 inch sheets. Very inexpensive and durable. If you got it in .032 inch gauge, it would be easy to make your slides with a pair of tin snips and a file. On the other hand, those stiff hanging file folders may be better for you. I would check out the local office supply store. Thickness is not critical, unless it's too thick.

[Colin Graham]

The septum is the core, or the centerpiece of the holder. The garolite from McMaster-Carr that Harold refers to works very well for darkslides and can be scored and snapped with a utility blade. I used this when making film holders earlier this year. I used the 1/32", but you might want to check that thickness against your holder.

[Ernest Purdum]

Any time I want to find some material or some gizmo I can't buy in the local stores, I automatically think of McMaster- Carr.

[C. D. Keth]

In hobby shops, you can get plastic sheets in various thicknesses from about .001" to .25" or so in .005" increments. They come in most colors including black and aren't painted, but are dyed the same color throughout so you could cut them and still have black edges.

[David A. Goldfarb]

When I've done this, I've just used a spare darkslide from a defunct holder or purchased an extra darkslide, which comes with the convenience of a handle.

[Ken Lee]

You might find posts about it in the archive. Various plastic covers available in paper shops can be used - they are semi rigid, black, easy to cut, cheap. Not so rigid as metal ones but usable.

I stopped by the local office supply store and bought a black plastic presentation cover. I will cut it down and give it a try. For 99 cents, it seems like a good first step. If I am careful, I can make another copy and place it over the ground glass, for use when composing the photo.

[GPS]

Ken, let us know how it worked for you, for the future reference. Good luck.

[Ken Lee]

I tried the plastic from the "report cover". It works as a dark slide, but it's a bit flimsy, once I cut out a rectangular portion.

I now better appreciate the choice of materials that go into modern holders.

[Colin Myers]

Beware. The plastic used for Dark Slide sheaths is of a special, anti-static type.
They are normally strange thicknesses for the regular formats. Careless withdrawal of a slide made from regular plastic, could result in a quite a firweorks display inside the holder, with resultant film fogging. Why not cut down a regular slide to make your custom mask. This would be certainly be anti static and probably the correct thickness.
Colin Myers

[GPS]

I tried the plastic from the "report cover". It works as a dark slide, but it's a bit flimsy, once I cut out a rectangular portion.

I now better appreciate the choice of materials that go into modern holders.

Not everything is lost yet. Try to put scotch on both sides of the cut version. Will not increase the thickness, only the stiffness.