Lens Coding

rcerick · 08-05-2010

A question - I recently bought a Zeiss 35mm Biogon C 2.8 and coded it manually in my M9, as recommended here and elsewhere, as a pre ASPH Summicron. I then bought Tim Isaac's Decoder 2.0 kit and coded the lens as a 35mm Summarit, thinking that the Summarit was closer to the Zeiss in f stop / speed. I only took 50 or so pics with the manual / in camera Cron coding, and have been shooting since (400 or so shots) with the Summarit coding on the lens. Both settings seem to yield suberb results, and I can't really see or remember a difference in IQ between the two settings.
I have seen that others continue to code the Zeiss as a pre ASPH Cron (perhaps even with the decoder kit or having the lens coded professionally). Does anyone have experience with the IQ of each setting and whether the Cron is a better choice for coding the Zeiss? Is there a definitive answer here or is it really more a matter of personal preference?
Thanks,
Rich

scottwallick · 08-05-2010

I shot some frames of a white whale with the C Biogon 2,8/35. I bought the images in to Lightroom, had a look, and then made my decision (I didn't keep the images).

I tried the following codes:

* Uncoded
* As Summicon 35/2 pre-ASPH
* As Summilux 35/1.4 pre-ASH
* As Summarit 35/2.5 (pen coded since this isn't in the menu)

I liked the evenness of the exposure of the white wall with the lens coded as a Summicron 35/2. In my opinion, using the lens uncoded resulted in darkened corners.

So that's what I decided; probably best to do a similar experiment and see what results you like most.

(After I decided on code, I removed the rear flange of the lens and used a Dremel tool to create recesses for permanent coding. I think painting the black and white dots with RustOleum.)