Re: [Leica] rookie mistake with the DR Summicron?

[ken@iisaka.org]

On Fri, 05 January 2001, "Patrick G. Sobalvarro" wrote:
> Some months ago I bought a DR Summicron in Zurich, and I had my first
> opportunity to use it over the holidays. I have an M2, which works fine with
> my other lenses.  I mounted the Summicron and got an entire roll of very
> out-of-focus images.  They have a beautiful dreamy quality to them, and I
> appreciate this because I harbour a guilty affection for the
> photo-secessionists of the last century, but the truth is that I have no
> desire to emulate them.
>
> - The rearmost element I see is smaller than the rearmost element on my
> Summarit, and seems deeper in the barrel, but that seems to make sense.  I
> don't have another Summicron with which to compare it.

I wonder if you're missing the rear most element of the lens.

Unscrew the lens head from the helicoid unit.  The rear most element should be just about at the end of the brass lens barrel.  If the rear most element is still deeply recessed, you're missing the rear most positive element.

Alternatively, stop down to 16, and count the number of reflections on the glass/air surfaces.  From the rear, you should see 4 reflections, and perhaps a very faint 5th.  From the front, you should see 8.  The front group in front of the iris has four elements (+-+-) in four groups, and the rear group has 3 elements (-++) in 2 groups.