Cz 50 Sonnar lenses

[cschwer]

I have a question. I have just begun hooting with Contax IIa and IIIa cameras. I have one of each... I also have both 50 1.5 an 2.0 lenses. both are post war versions. Was the 50 1.5 sonnar optimized for shooting wide open or nearly so? this lens seems quite soft stopped down beyond F8.0... The Sonar 2.0 seems much better in the smaller apertures or for general daylight purposes..... Is this correct? If so one would really need both lenses
to accomodate normal shooting situation..... Thanks

[furcafe]

Sounds about right to me, though I haven't noticed any huge difference @ f/8 & smaller between the f/1.5 & f/2 Sonnars. I know diffraction starts to kick in, but I shoot mostly in the f/1.5-5.6 range, so I'll let the landscape-type guys/gals weigh in.

[D.O'K.]

Interesting--assuming broad equality of shooting conditions, I see no significant difference in the performance of my f1.5 and f2 Optons at apertures smaller than about 5.6, with both showing similar diffraction losses after f11. The f1.5 is however much the better up to about f4-f5.6.

Hard to know whether our differing experiences are owing to sample variation-particularly some 60 years after manufacture.

Regards,
D.

[cschwer]

Thanks for the opinions...I have to admit I was surprised by how much diffraction the 1.5 lens exhibits when stopped way down. My 2.0 Sonnar does not seem to have that much.

Thanks again... Chris Schwer

[porktaco]

what i've read on the 1.5 is that since the dof is so narrow, it was recommended not to shoot wide open unless at infinity. i have it in mind that this was from a zeiss user guide.