And last the Summicron v1 collapsible (mine is a perfectly mint M mount version without cleaning marks):
much, much smoother bokeh without distracting patterns, higher contrast, more neutral, less "artistic" rendering:
portrait - man with kite closeup by
teknopunk.com, on Flickr
strong backlight is a lot better controlled, but still lovely compared to the drop dead boring new ASPH rubber doll lenses:
drive by shots - woman on e-bike by
teknopunk.com, on Flickr
I think, this is the only shot, I have online with the Summicron v1, where I possibly stopped down to ƒ2.8 or ƒ4:
construction site by
teknopunk.com, on Flickr
The Summicron is my "safety net" 50 ƒ2 classic lens.
It has classic rendering for beautiful B&W contrasts, is a slightly bit softer wide open than the Summitar (in centre), but manages difficult light absolutely predictable and reliable.
I also like it's modern, stepped aperture control - much easier to set fast with a meter less body.
The Summicron protrudes the least, when collapsed.
The Summicron fits perfectly with the fantastic Leica conical lens hood for it, which I just love - it's the most perfect lens of the three in all accounts.
For me, this would be the lens of the three, if only one of them could be around.
The other two are more specialty lenses.
If you can find a nice Summicron, you could later pick up a scratched up Summitar/ Summar for special purposes (bokeh, low contrast, …)