Zeiss 7 x 42B Dialyt (1 Viewer)

[Spartacus]

I have a pair of Zeiss 7 x 42B Dialyt binoculars, which have the symbols T*P* on the front of the cap in front of the focussing ring.

I've been offered a second pair,which instead simply have the T*, i.e. the P* symbol is not present. Does this mean these are inferior to the ones I already have, and are they worth buying, or not??

 

[dogfish]

the missing P means they don't have phase-coated prisms, and so are in theory at least slightly inferior
Sean

 

[Kevin Purcell]

the missing P means they don't have phase-coated prisms, and so are in theory at least slightly inferior
Sean

It makes a difference. For example, search for the comments on the thread phase compenation paper here. There was an excellent test using Zeiss 10x40B bins but with differing coatings.

http://www.birdforum.net/showthread.php?t=124362

It also means they're pre-1988 (when P* was introduced on these bins).

 

[Spartacus]

Thank you both for your prompt and helpful replies. Thanks especially Kevin for directing me to that other thread, most interesting. I think I'll let them go...