[Leica] Jupiter 3 (1.5/50 ) review

["Stanislaw B.A. Stawowy" <watteau@krakow.neurosoft.net>]

(As my contribution to group, I choosed to try to describe
some of Russian lenses and provide samples & info about
them. I know that this is not a pure "Leica" subject, but
because this is a *users* group, these informations may be
of some importance. There was some info about them in early
Digests, like these from 1998, but not all. I hope I will
see Marc Small someday, writing something like a series
of articles describing Russian lenses in LTM <g>)


                   #  Jupiter 3  #

My example has serial number 6310911, what gives me some
reasons to suspect that this lens was made in 1963.
Glass is clean, with some light scratches on front, 
visible only when carefully looking at angle. Glass
is coated on all air-glass surfaces. Colour of coating
is deep blue. On front element coating is less visible.
Dimensions are (without mount, set at infinity):
Length: 36 mm 
Diameter: 46,5 mm in widest place 

Filter mound diameter is 40,5 mm 
Distance scale is from 1 to infinity 
Diaphragm goes from 1.5 to 22 w/o stops

Internally, this lens is made of seven elements in three
groups (correct me if I am wrong). Front element is a
strongly curved planoconvex (good word?) single lens.

When I first time saw this lens, I suspected that such
a desigh would result in strong residual chromatic aberration
and strong coma. To my surprise, I was wrong.
Lens has some 14 or so diaphragm blades, that high a number
results in very pleasant apperance of out of focus areas,
also in-focus things are not harsh, like in Nikon glass,
but softer (did anyone noticed this harshness of Nikon 
lenses?)
Speaking about softness: this does not mean that this lens
is a dog; look below at test.
Test was made in Optics division of catedra of Physics
at Pedagogical University of Krakow, using a Zeiss optical
bed and measuring devices (micrometers and range meter). 
Film used in test was Agfa APX 25 (discontinued, sigh!),
developed then in Agfa Rodinal 1+25, fixed in FOMA RapidFixer,
then tested under Zeiss microscope at 50-200x ,magnification.
Test target was a set of USAF test charts, places in center 
and five corners of 60x90 cm rectangle. Test charts were
printed at 2400 dpi.

Results are: 
This lens performs adequately at f/1.5 to f/2. There is
noticeable softness, especially at f/1.5, but center resolution
is about 55 lpm and corner 38 lpmm. After that, there is strong
resolution gross, which peaks at f/4 to f/5.6 (103 lpmm center,
92 lpmm corner) and slightly diminishes after f/8. At f/11 to
f/16 resolution is still well above 70 lpmm in center. At f/22
resolution diminishes to that at f/2.

Some non-scientifical results:
I am a nocturnal shooter. This is a kind of ugly person,
so ugly that travels in the night, and stupid, so stupid
that is on these dark, dangerous streets alone <g>
I am using this Russian lens very extensively. Main reason is
that this lens almost lacks flare, so street lights seems
"as real". Also, when fogs from bright light source, this lens 
does so only in a close surrounding of it, so very bright 
streetlight fogs only half of his diameter around.
One peculiarity is that with aperture set at f/11 and below,
lights have "rays" coming outside, like these with "star"
filter. This is a very hard to spot behaviour, you have
to photograph very bright and very small streetlight, 
also you have to overexposure by 2-3 stops to see this.

I will put some of photos taken with this lens on net
in next week. This will also give me a reason to make
my own website at last :-)

                                    St.                

Ohh yes. And lens is silver.