Quarzglas lens 270mm f/4 apherical

[arri]

Today I revised my Quarz glass lens, I have to change the position of the waterhouse stops to make it usable for 18x24cm/8x10"
It is a fused silica lens, made by Carl Zeiss in the 1990th. It were an element of the lithographic lenses Zeiss build for the chip exposuring.
It is an apherical lens so the focus length is a little bit difficult to messure but the extension at oo is 270mm and the used diameter ist max. 70mm (f/4.9)
For this sample I used a f/11 self made waterhouse blade.

The sharpness has is untypical, one reason is the not spherical corrected lens and the asperical surface.

The quarz glass let pass the UV light down to 185nm. The UM-MA has an UV sentivity of 320nm, I guess.

The Hanover company produced a similar lens in the early 1920th with the name Kalosat. It were a convex / concave miniscus lens. My lens is C/C as well but not so extreme.

Fujifilm X-Ray UM-Ma in 18x24cm
Sinar with rear lens shutter
1/2 sec., f/11
Wehner Developer

[Daniel Unkefer]

NICE. 18x24 Eh Looks great with that border around it. Like the BOKEH it pulls you in might hurt your eyes. WOW

[arri]

NICE. 18x24 Eh Looks great with that border around it. Like the BOKEH it pulls you in might hurt your eyes. WOW

I think 18x24cm is too much for this lens,but I have to test it.
4x5" or 9x12cm will be better choice, when I make a cut out in this size I get a good quality and 270mm is a focus length for portraits in this sizes.

Now I´am working on a 350mm lens, two elements, one quarz and one CaFl glass. It is very large because the front lens has a diameter of around 160mm.