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Full Version: Zeiss Tele-Tessar 500mm f/8 - well travelled, US$0.5M estimate
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Anyone looking for a 45 year old Zeiss tele lens? That's been dropped, and repaired with duct tape? Possible dust contamination which makes it more valuable? This doesn't make sense? It's been to the moon!

 

http://www.engadget.com/2016/04/20/forme...apollo-15/

http://www.rrauction.com/browse_gallery.cfm?category=69

 

Wonder how it would perform by modern standards. Might never find out as I'm guessing whoever buys this will probably end up keeping it in a glass case.

What more than 4 euros!....  Rolleyes

Dunno if I am understanding things wrong, but a lens designed to work in air glass environment, will it work the same in glass nothing environment ?
Because of focus-breathing or what?

 

 

B)

No, because of the light refraction air/glass, try to immerge a lens in water without any housing will it function the same optically?
 Water?

 

We (human beings/opticians),  are used to using the general term "air to glass surfaces" as a way of saying;

 

           "light passing through a refractive medium into free space".  

 

 

 On Earth in our case, free space contains air........... On the moon there is no air....  but light passing through refractive mediums into a vacuum is still same......only that the light rays are not degraded by air's refractive properties.....

 

 

   (On Earth we call it focus breathing JoJu..........on the moon it's called focus (last) gasping)...   :o

Quote:Dunno if I am understanding things wrong, but a lens designed to work in air glass environment, will it work the same in glass nothing environment ?
 

Look at the refractive index:

Vacuum: 1.0000

Air: 1.0003

Water: 1.33

Glass: 1.52 (Schott BK7)

 

So is the difference between air and a vacuum significant? For photographic purposes I'd say no.
Quote:Look at the refractive index:

Vacuum: 1.0000

Air: 1.0003

Water: 1.33

Glass: 1.52 (Schott BK7)

 

So is the difference between air and a vacuum significant? For photographic purposes I'd say no.
now that makes sense

Many thanks popo for clarifying