I’ve been thinking about this for some time.
Using the cheap and readily available fresnel lenses, would it be possible to build a box with a reflex mirror à la the one on TLRs?
The advantages of fresnel lenses would be that due to their size they will A. Produce a very bright projected image. B. Have a very shallow DoF which would make focus very easy. C. Be much lighter than equivalent glass lenses.
The disadvantages would be worse image quality and perhaps distractingly shallow DoF, making composition harder.
But AFAICS the advantages outweighs the cons.
You could make it a simple pull out box in a box or even try to put a knob and tooth rack on Rollei style.
You would make a distance scale, that you read off and transfer to the lens focus.
You could even make it fixed focus to your favorite close up distance and just step focus in.
You’d be able to build it pretty easily and light, with foam core or thin plywood.
Put a cold foot or a tripod screw on it, and it would be a ready part of the camera.
I’m thinking folders and scale focusing cameras would benefit especially from this.
Has this been done before and/or is it a stupid idea?
The challenge would of course be to make the plane of focus correspond exactly to the cameras.
Using the cheap and readily available fresnel lenses, would it be possible to build a box with a reflex mirror à la the one on TLRs?
The advantages of fresnel lenses would be that due to their size they will A. Produce a very bright projected image. B. Have a very shallow DoF which would make focus very easy. C. Be much lighter than equivalent glass lenses.
The disadvantages would be worse image quality and perhaps distractingly shallow DoF, making composition harder.
But AFAICS the advantages outweighs the cons.
You could make it a simple pull out box in a box or even try to put a knob and tooth rack on Rollei style.
You would make a distance scale, that you read off and transfer to the lens focus.
You could even make it fixed focus to your favorite close up distance and just step focus in.
You’d be able to build it pretty easily and light, with foam core or thin plywood.
Put a cold foot or a tripod screw on it, and it would be a ready part of the camera.
I’m thinking folders and scale focusing cameras would benefit especially from this.
Has this been done before and/or is it a stupid idea?
The challenge would of course be to make the plane of focus correspond exactly to the cameras.
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