What am I missing out on with my terrible lens boards?

[Vascilli]

So earlier this year I picked up a beat up Eastman Commercial View 8x10. No lens, no boards. No problem, I have a Rodenstock 480mm from the 4x5 kit I bought a few years ago that hasn't been used for lack of bellows draw. Okay, what about the lens board? Well the Commercial View takes 6x6 flat boards so dad and I get some cheap aluminum plate, cut a 6x6 square, then cut out the sorriest excuse for a circle possible using a drill to make holes about the circumference and a jigsaw from hole to hole to punch out a gear-looking thing. Liberal use of a file turned the hole into some sort of egg circle, and finally the lens fits. Put it on the camera and boom there's an image in the ground glass. Fast forward to a few days ago and I'm doing the same thing for a wide-angle. Coated the inner sides of both boards with some matte Rustoleum and things seem okay. Took four exposures or so with the 480mm in May and the slides look fine. The wide-angle shows an image and I ought to be taking some photos with it once the shutter's working. Now I know my scientific instrument maker grandfather is rolling in his grave over our absence of any figment of precision, but with a ground glass that shows stuff I'm pretty happy. Is there really anything to benefit by having properly made lens boards or should I just carry on wasting film in my pile of scrap?

[Steve Smith]

It doesn't need to do much more than hold the lens in place and not leak or reflect light. If it does that without falling off then it's as good as any other lens board.


Steve.

[Vascilli]

As I thought. We made a prototype of masonite and I think it was actually a bit better. Besides being much easier to make and lighter, the inner side was completely matte after paint. These ones still have a slight sheen so I might glue some felt on.

[Leigh]

The only potentially critical aspect of a lensboard is that the face is really vertical when the board is mounted.
If the board is not accurately vertical it can introduce slight distortion in the image.

Most better lensboards have bosses accurately machined on the reverse, abutting surfaces on the front
standard, to ensure that this condition is met.

I suggest that this is not a concern in the general case, and you shouldn't worry about it.

- Leigh

[Shen45]

Vascilli,Vascilli,Vascilli

You are letting done the side by being active in the production of a lensboard. You need to agonise for weeks about whether the hole is round enough or whether the aluminium is the right thickness and whether the thickness is uniform to within the tolerance of a bee's -- whisker. You need also to stress for weeks that even though your results are excellent - could they be better by paying $200 to have a super duper board made for you? Also don't forget you need to ask many more questions on the forum as to the brand of drill to use, the type of CNC machine to buy and what version of AutoCad needed to design the superior board. When and only when the post count reaches at least 100 will you have enough information to approach this daunting task head on -- or you could use the great effort you have already made and really enjoy some great photography. Some of the guys here have been known to use matt board and hot glue as a temporary measure and never get around to building the final product. All of what I've written is tongue in cheek. Well done.

[mdm]

Ha, ha, ha. You need a 500hp chainsaw with the drill attatchment to make a suitable hole in a block of solid mahogany, or a 500t mill to machine down a hunk of steel heavy enough to weigh down the hulk. Not to mention a PhD in lens boardology. Some experience in rocket controll sytems and electronics is quite a help. Most of all you need to know how to spell. A fondness for mushy pixies and post pimple high school seniors wont be out of place either. Please stay away from front movements when making portraits, so your lensboard wont fall out.

[Bob Salomon]

A lensboard has a few things that make it work properly.
1 it has to fit the camera and not leak light.
2 it has to hold the lens and not leak light.
3 It has to be flat and be parallel to the ground glass at all points when no movements are used.

That last step is why lensboard holes are not made the way yours was.

Holes in lensboards are milled, not drilled. Drilling can create problems where the board is no longer perfectly flat.
If the board can't be milled then another option is to use a Greenlee punch.

Since dwpth of focus is more critical with shorter lenses that could mean that if your technique created a problem it would be more likely to show up with the wide angle, not with a 480mm.

[Fotoguy20d]

Matte rustoleum is fine. Drilling the board is fine - if the edges are rough or mushroomed, use a dremel or sandpaper. Masonite is fine. As long as the thing is light tight (electrical tape can help there), and everything fits snugly and nothing goes splat on the concrete, just have fun with it. If you're not happy with the results, then you can worry about wood/metal working. But, I'd be surprised if it ever came to that.

Dan

[DKirk]

Hey, I made one of mine from 4mm Aluminium sheeting from a cut out from those boards that are an aluminium sandwich with a polystyrene filling. Thats holding a 360mm f5.6 symmar and it's holding up fine. Though on the cosmetic scale it does make fugly look attractive. . .

[Jody_S]

Old masonite is a great source of material for lensboards, especially if you're not planning on leaving a lens permanently attached to the camera (so you don't care what it looks like). I personally use old pieces of pre-finish from the 70s, it's a thicker material than the current cardboard pre-finish, and the back is actual laminated wood. The wood can be stained and varnished to resemble mahogany, if I ever feel like making one pretty and finished-looking.