[Leica] Jupiter lens 'tests'

["Jem Kime" <jem.kime@cwcom.net>]

Folks,
there was conversation a while back about the (Leica fit) Soviet Jupiter 8
and Jupiter 3 lenses so I decided to see how they compared.
I just got a roll of K64 back this morning and have been able to look at the
pictures to make some notes.

I compared the
Jupiter - 3, 50/1.5 (Cyrillic script) black anodised lens I have, 850104
with a
Jupiter - 8, 50/2 (English) black anodised, 7530131
Jupiter - 8, 50/2 (English) black paint, 034280
and a
Industar - 61, 55/2.8 (Cyrillic) black anodised, 9220210

Projecting the slides via a Pradovit Color 250 via a Colorplan 90/2.5 and
then an Elamron 50/2.8, I was able to see amgnifications of up to (around)
50x enlargement. Naturally all pictures were taken on a (Leitz Tiltall)
tripod.

First off I looked at close focusing (at 1m) at both maximum aperture and
most likely optimum (f5.6).
The Industar was the star performer here, especially at 5.6, beautifully
resolved fine detail into the edge of the picture, though the others were
not far behind. The Jupiter 3 being no different to the Jupiter 8s.
At maximum apertures the wider designs showed softer images and some imaging
flare.

Secondly I tried to assess contre-jour flare by framing a shot looking at
dark foliage in shadow with the sun just out of frame, infinity focus.
There seemed to be no difference visible and no spectral discs or curves
shown either.

Finally I looked at long distance (infinity) focus with the sun behind me on
a wide view of our town.Here the ability to resolve bricks on buildings
progressively further from the camera was my criteria for assessment.
The Jupiter 3 wide open was, not suprisingly, the softest, but staggered me
with its ability to show the best picture at f5.6, beating both the Jupiter
8s and the Industar.

What impressed me overall, though, was the ability of these lenses at all
apertures to deliver pictures that were not at all disappointing, especially
bearing in mind the cost. I dare say the variations in samples would negate
placing any great store in this little asessment but flare control was
markedly better than my well worn (and loved) 35 Summilux-M.
I recognise that at close distances I was testing the accuracy of the
focusing cam as much as the lens ability but no example seemed to be out of
focus.

The black anodised 50/2 seemed just a little better than the black paint
version, in terms of sharpness of fine detail, especially at 1m, but sample
variations could count for more.

The Industar appeared to have a FED engraving, the two Jupiter 8s had the
Zorki dipping arrow through a trapezoidal prism, and the Jupiter-3 an arrow
through a convex lens then a circle and appearing from the right hand side.
I had not previously seen this symbol before.

Jem