How well will the M8 work with the Zeiss Biogon 21mm

Not that I'm running out there to get a M8, but the availability of a M8

fueled my WHAT-IF day dreaming. The widest wide angle I use today is a 24mm,

which becomes a 31mm with the M8. In order to get something close to a 24mm

perspective, I'll need to get a 21mm (or wider) lens, which is another

sizeable investment in addition to the M8. Here's the question: If I get a

Zeiss Biogon instead (cheaper), will the Biogon work with the M8? Suppose I

find a way to code the Biogon to "fool" the M8 to believe it's a Leica 21mm,

will that even work given the Zeiss lens is a Biogon design with a different

imaging characteristics compared to the Leica?

The "lens coding" is only applied in the RAW to JPEG conversion. If you shoot RAW (wise idea in any case), the coding is a non-issue.

 

I'm sure that the new C Biogon 21/4 is squarely aimed at the M8 marketplace.

I just tried both my Leica 21 and my C/V 15mm on an M8 Saturday. Neither lens is coded.

Seen on the LCD, images from both lenses showed very little corner darkening, and

certainly less than on the slightly smaller sensor of the Epson R-D1.

 

So the offset microlenses already do a pretty good job of reducing sensor vignetting, all by

themselves.

 

Therefore, unless there happens to be something wonky in the optical design of the Zeiss,

it should work quite well "straight". And from the diagrams, the ZM Biogons are fairly

digital-friendly designs in their own right. Sean Reid noted a bit LESS fall-off from the

Zeiss 21 compared to the Leica 21 on an R-D1 (at reidreviews.com...worth the $26.50

admission fee since he is testing a whole host of Zeiss/Leica/C-V lenses on the digital M-

mount bodies as they appear) - but was not as happy with C/V 21/25/28 performance.

 

My basic take on the coding is - I'm not even bothering to get it for my Leica lenses until I

see some evidence that it actually makes a significant difference to images.

Forgive my ignorance, but why couldn't the user just tell the RAW converter software which lens was used in order to benefit from the same corrections as would be provided if the lens were coded?

 

A simple set of drop-down lists of lenses would accomplish the same thing, no? I'm sure Leica wouldn't want to include other manufacturers' products, but a third-party converter could. The Leica software could provide models for all of their lenses, coded or not, unless they truly need the income from aftermarket coding.

 

There are already software packages that purport to make compensations/corrections for lens characterstics/deficiencies. DXO's uses installable "Lens Modules," i think.... They don't rely on lens codes, do they? Just EXIF, or manual imput?

If it's a standard tag (and quite possibly if it isn't) you'll be able to add lens data manually using something like ExifTool. Of course having a raw converter that can do anything useful with this information is another matter.