- Joined
- Dec 19, 2017
- Messages
- 2,712
In an image discussion, here, David M and I were talking about the size of a wide angle lens the 165mm f8 Super Angulon.
Now these weigh around 1.7 kg with a lens board and lens caps and aren't really practical for field work. In comparison here's two other wide angle lenses a 159mm f12.5 Wollensak and a 141mm Ross AM Wide angle (unmarked but a Ross Zeiss WA Protar).
As mention the 165mm SA weighs 1.7kg / 1,700g, however the 159mm Wollensak EWA weighs 340g and the Ross 141mm wide angle only 75g but it has no shutter. Although uncoated the Wollensak and Protar only have two internal air glass surfaces so are reasonable contrast, the widest marked aperture of the Wollensak EWA is f12.5 but it opens to approx f9 for focussing.
Ross made the WA Zeiss Protar under licence and with a max aperture of f16 it was a touch faster than the Carl Zeiss Jena version which was f18. During WWI Ross took over the Carl Zeiss London Mill Hill works and stopped using the Zeiss name & Patent No's (and paying royalties) on any Zeiss designed lenses they made. The Zeiss Mill Hill works was predominantly Binocular manufacture but some Carl Zeiss London Tessar lenses were made, Ironically Ross then continued the Binocular manufacture for the British armed services
Earlier this year I bought a near mint 120mm f6.8 Angulon (for £90) I'm very surprised to find it illuminates the 10x8 screen to the corners at Infinity, here will be slight fall of due to vignetting but would improve by f45, It's made me realise that a 165mm f6.8 Angulon might be a good option at 310g it's substantially lighter than the equivalent Super Angulon and very portable.
Ian
Now these weigh around 1.7 kg with a lens board and lens caps and aren't really practical for field work. In comparison here's two other wide angle lenses a 159mm f12.5 Wollensak and a 141mm Ross AM Wide angle (unmarked but a Ross Zeiss WA Protar).
As mention the 165mm SA weighs 1.7kg / 1,700g, however the 159mm Wollensak EWA weighs 340g and the Ross 141mm wide angle only 75g but it has no shutter. Although uncoated the Wollensak and Protar only have two internal air glass surfaces so are reasonable contrast, the widest marked aperture of the Wollensak EWA is f12.5 but it opens to approx f9 for focussing.
Ross made the WA Zeiss Protar under licence and with a max aperture of f16 it was a touch faster than the Carl Zeiss Jena version which was f18. During WWI Ross took over the Carl Zeiss London Mill Hill works and stopped using the Zeiss name & Patent No's (and paying royalties) on any Zeiss designed lenses they made. The Zeiss Mill Hill works was predominantly Binocular manufacture but some Carl Zeiss London Tessar lenses were made, Ironically Ross then continued the Binocular manufacture for the British armed services
Earlier this year I bought a near mint 120mm f6.8 Angulon (for £90) I'm very surprised to find it illuminates the 10x8 screen to the corners at Infinity, here will be slight fall of due to vignetting but would improve by f45, It's made me realise that a 165mm f6.8 Angulon might be a good option at 310g it's substantially lighter than the equivalent Super Angulon and very portable.
Ian