Distagon 40mm C compared to 40mm CFE

[Ayler]

[FONT=Verdana, sans-serif]Hello all,

I'm new to this forum and not (yet) a Hasselblad V user (although I owned a number of its archrivals Rolleiflex TLR and Rollei SL66 for many years).

However, I'm seriously considering the Hasselblad Distagon 40mm (and other Hasselblad lenses) adapted via a Mirex T/S Adaptor as tilt/shift solution for my Sony A900. This is one of the few workable shift options available for this camera without the need for lens mount conversion (a la PC Distagon), plus it’s flexible and I’d have the option of using it with other excellent Hasselblad lenses in the long run.

I'd like to know the optical differences between the old C, non-floating element, version of the 40mm Distagon and the new FLE. Particularly in regards to performance in the centre and around the extreme corners near infinity stopped down a bit and how much better corrected the new FLE is? Since the old C is so much more affordable and the MTF graphs on the Zeiss website don't seem to give that much of an upper hand the new version (at least from how I understood it), I wonder if the old will suffice as a first foray into the world of DSLR tilt and shift.

My main doubts about the old C are:

- Field curvature near infinity and not getting everything in a single plane in-focus because of that (not bothered by close-up performance). Is this a problem with this lens and is the FLE better near infinity?

- Sharpness across the field when shifted and closed down to f8/11 (not bothered by performance wide open). Is there a difference between the two lenses near infinity when stopping down?

- Control of CAs, especially near the corners, closed down to f8/11. Is the older lens worst in this respect and is it a problem with digital backs (assuming there is any)?

- Flare control with point-light sources.

- Distortion (again, not bothered if it’s ‘normal’ barrel, but wouldn’t like to see something wavy like moustache distortion). The MTF graphs seem to point to the older lens displaying less distortion at the measured focus distance, is this true?

Any help with any of the topics in this convoluted post would be much appreciated.

Thank you!

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[polypal]

Against popular believe the old C designs performs quite well even compared to the later FLE design.

Still for a number of reasons the later FLE lens is the better lens by a small margin.
Less flare, higher resolution.
Distortion is slightly up from 1% max for the C lens to 1,5% for the FLE design.
Distortion is of the barrel type and quite good for both lenses.

Please note all MTF readings from Zeiss are done at infinity.
With one exception that concerns the Macro lenses.

CA is less for the FLE design.

I would go for the later design also for practical reasons.
Less weight, easier filter size.
The price difference is getting smaller as time goes bye.

 

[blowupster]

With wide lenses, it's harder to get flat light. So easy to have the sun or direct light in the picture. So you can imagine that a newer lens that have less flare is more interesting. With digital back, beter resolution (MTF curves) is needed from the lens. The fact that the CWD is offered with this lens (40mm IF CFE) in the US is not an accident.