Soft Portrait Meniscus Lens, Mounted
Here's a 285 mm f 4,9 soft portrait simple meniscus lens, all mounted and ready to go...
This lens is aimed primarily at the 5x7 large format portrait camera user.
(You'll need 285mm of bellows draw just to focus at infinity).
While it will throw an image well over 14" diameter, light fall-off must be expected from this most basic of all photographic lenses. Focused at 10 feet (3 meters), the field of view is about 4.5 feet (1.4 meters) wide
If I get enough interest, I'll make one for 4x5 (somewhere around 150 ~ 180mm)...
Being a simple positive meniscus lens, using it wide open results in very soft and "dreamy" image. Using progressively smaller aperture cards will increasingly sharpen the image. The attached portraits were made using the 35mm diameter (f8.0) aperture card.
Focusing a wide open meniscus lens is challenging, especially in low contrast lighting. Pre-focusing using a card one-stop larger makes focusing easier.
Five aperture cards (aka: "Waterhouse Stops") from f4.5 to f16 are included.
The aperture cards have a simple chart listing effective apertures at 10' and 3' focusing distances. The cards are die-cut from black & white matboard, the black side faces the film, the white side is for making notations...
The lens itself is a positive meniscus glass lens from a well known supplier of surplus optical components and has been mounted in a machined barrel.
The lens barrel is 3" long x 2-7/8" diameter PVC tubing.
The lens itself is mounted 15mm in front of the flange (this amounts to a 15mm "extended lensboard").
The card slot abuts an internal ledge which acts as a light trap to minimize light spill around the edges of the card during exposure.
The PVC flange is 3-5/8" diameter, 3-3/8" across the flats.
Four countersunk screw holes for #4 flat head mounting screws.
Specify if you'd like brass or stainless screws. (#4 x 3/8")
A lens board hole of about 2-1/4" diameter (60mm) is suggested.
$65 + shipping.
This is pretty cool! I've been looking at Hermagis meniscus lenses for my 4x5. I'm impressed.
Kent in SD
If you build one in 4x5 I would need to have it LOL Pretty images
Very nice! How would this perform for whole plate or 8x10?
I wish I had an 8x10 to try it on...
I did a rough preview with my 8x20, and could see an image almost all the way across 20 inches (wow).
But judging light fall-off is a guessing game at best.
Maybe one of the optical experts among us could calculate fall-off at various radii (lens focal length -vs- image circle).
I'm half tempted to sacrifice a sheet of film just to see how it works...
To address your question directly;
You will get full coverage across 8x10.
Vignetting (a distinct edge) is not visible.
Light fall-off is plainly evident at a 14" image circle.
My guess... at 12" (the approximate diagonal of 8x10) fall-off would be about 1 stop at the corners.
I gotta go borrow an 8x10...
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I bet it will look great at 8x10!
I have several meniscus type lenses and they are so much fun to use!!
first example: small Lancaster meniscus on 4x5 ("too" big for that lens..)
secondallmeyer meniscus on 13x10 (clost to 5x7)
For those of you wondering if this lens would work on a 4x5 camera, here are a few numbers:
My Tachihara has 12" (305mm) max bellows draw.
With this lens on my Tachi., the closest I can focus is 6'-3" (1.9 meters).
The field of view is 21" (533mm) or about the width of my shoulders (I'm of slight build).
So this lens will do a "head and shoulders" portrait (vertical format) on a 4x5 camera.
If your camera has 16" (406mm) bellows draw, you can focus as close as 40" (1.0 meters).
I would be interested in the aforementioned 150-180mm 4x5 lens. Let me know if you decide to make any.
I should have said that the field of view is 21 x 26 inches (533 x 660 mm) on 4x5 film when focused at 6'-3"
Yeah, I would also be interested in a lens for a 4x5. Thanks.