Leicas BA and BNs (3 Viewers)

[elkcub]

Hello Bill,

Although differences in colour temperature may be demonstrated to me, like your customers, I have never had an issue with colour temperature. I also kept my bicycle's spare ball bearings in plastic containers.

Happy bird watching,
Arthur :hi:

:hi: Is that individually?

Ed

 

[Patudo]

... several of the Swift 804 binoculars had identical optical trains but differed in their multi-coatings. I do experience systematic differences in contrast and color intensity between them, which can be seen in transmission spectra, but I further suspect there are also measurable/perceptible differences in CA as well.

Ed

I would be most interested to know if this was also true of the Zeiss Jena 8x30s, 10x50s and others that were multi-coated from the 1980s? Some info on the net states that Nikon's first E series porros were single-coated - but (from memory) the multi-coated ones do look slightly different, so maybe the optical train had changed.

I often wonder whether turning out multi-coated lenses (and phase-coated prisms) for the great old classics like Dialyts and so on could ever be a sensible venture. There must be thousands of them out there, but probably not enough owners who would pay for the new glass, as well as for it to be retrofitted. The glass can come from the PRC - I doubt a PRC factory (or probably anywhere else) will be producing anything with the fit and finish of a Leitz Trinovid anytime soon, but they appear well able to produce high quality glass.