Archived posting to the Leica Users Group, 1998/04/02

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Subject: [Leica] Ricoh 28mm LTM lens test
From: jeremy.kime@bbc.co.uk
Date: Thu, 2 Apr 1998 12:01:00 +0000

Ricoh GR 28mm F2.8 lens as tested by Stewart Bell in =C8Amateur Photographe=
r=C9, =

2nd April 1998

This is an addendum to my user report which I posted earlier on the group, =

this report was printed in this magazine today along with this technical =

test.

"The optical layout is, as far as I can discover, unique, with a small =

diameter negatively curved entrant face and a much larger diameter, =

positively curved exit face. In spite of the positive curvature of the exit=
 =

face, the rear lens element is in fact a negative component, as is the =

leading lens element; a rare occurrence. This is the first lens I have =

tested in which the primary purpose of the aspheric lens elements is to =

perfect the image resolution rather than making it (the lens - I presume, =

JK) smaller.
Leica users tend to be a bit snotty about non-Leica bits and bobs fitted to=
 =

their God-designed idols, but in this lens the lesser God has triumphed. Th=
e =

... price seems excessive at =9C800 (UKP) and the company does not expect t=
o =

make many sales. At that price neither do I, and found myself frankly =

incredulous when told there had been several sales in this country already.=
 =

For that money you can buy two Ricoh GR-1 cameras which use the same lens!"

Performance:
Colour shift: neutral
Distortion; not significant
Vignetting; below reporting levels
Low Contrast Image Quality; excellent
High Contrast Image Quality; excellent
Overall quality; excellent

Ratings:
Optical quality 27/30
Ease of Use 25/30
Construction 19/20
Value for Money 15/20
Overall 86%

A couple of graphs were drawn showing lines per millimetre at both low and =

high contrast.
At low contast, edge at f2.8 was 50 lpm, centre was 58 rising to 90 lpm (fo=
r =

both edge and center) in between f5.6 and f8, holding at 90 lpm to f16.
At high conrast, edge was 70 lpm at f2.8, center was 80 rising to 120 lpm =

(for both edge and center) at f8, dropping down to 90 lpm at f16.

Not definitive testing and terms are very subjective except in comparison t=
o =

other =C8Amateur Photographer=C9 tests (which I appreciate most of you don=
=C9t / =

can=C9t read) but something more than nothing to go on...
I'm certainly inclined to agree that =9C800 (UKP) for this lens is not wort=
h =

it, far better (at that price) to buy Leica, as I wrote originally, I got =

one as a swap for a lens I'd paid =9C15 (UKP) for!

Jem