UK Air Ministry brass LF lenses

[davidjt]

I bought an old Kodak whole plate camera which came with 3 very chunky brass lenses which have air ministry markings. I had expected to come up with a list of codes and what they are after a few googles but without success. Is there a good resource for these lenses ? They are superb bits of engineering and must be worth trying

AM No 14A / 1 / 27 8in F5.6 Anastigmatic
AM 14A / 2445 max 5in F2.9

One unmarked F2.5 lens with a focal length of about 5in which I will have do do some more research on.

Many thanks

Dave

 

[Ian Grant]

Many of these lenses were made by Ross, I have a small f16 151mm WA AM lens made by Ross, it covers 10"x8", in fact it's a Zeiss Protar design but during WWI Ross paid no license fees to Zeiss.

Many A(Crown)M lenses are WW1 vintage, Ross took over a relatively new UK Carl Zeiss factory at Mill Hill, London which was producing Military binoculars as well as some camera lenses, Ross also held the license to manufacture Zeiss lens designs for sale in the UK & Commonwealth pre WWI.

It's a poorly researched area but Ross & Zeiss had many agreements, some Zeiss lenses particularly EWA's were based on Ross patents and designs so the licensing went two ways.

Ian

 

[davidjt]

Thanks Ian, they really are magnificent lenses although the iris on all are very stiff but I hesitate to lubricate in haste. Optics are pretty much perfect.