At 09:46 PM 2/6/98 -0800, Larry Clark wrote:
>Rob Roy wrote:
>>
>> Last week a friend showed me his newly acquired 180mm/f2.8 Zuiko
>> which he had purchased...
>>
>> Last night he showed me some astrophotos he had taken before he
>> took the lens back to the store. I have never seen anything
>> like them. The stars were football-shaped (astigmatism) and the
>> brighter ones had blue halos around them (chromatic aberration).
>> Any ideas as to what is going on? I have never even heard of
>> such a bad lens!?
>
>Is it the 180 f/2 or the 180 f/2.8 that is well known for chromatic
>aberrations -- and therefore not a sweet deal for astrophotography?
>
I have found the following from my mailbox.
(I have recently considered buying a 180/2.8, so this lens thread piqued my
interest)
>I'm not certain, but I believe the NASA 180mm was the f/2. At the time
>that it was tested (apparently they test all equipment that they are
>considering for use in space) it was said that that particular lens (the
>180mmf/2) was the sharpest 35mm format lens that they had ever tested. I
>have an old Modern Photography around somewhere circa 1985 that listed
>lenses NASA was going to be using and from memory I know the 180mmf/2 and
>28mmf/2 were included and I think the 50mmf1.4 but anything else has been
>forgotten. I can try to dig up the issue this was in and confirm.
>I have owned both lenses (180mmf/2 and 180mmf/2.8). The f/2 was truly
>phenomenal and the f/2.8 was very sharp and contrasty but had this strange
>purple fringing/flare around backlit or highlight areas (probably pretty
>noticeable on stars against a black background---maybe the cause of the
>"dog" reputation with astrophotographers). It was very subtle but it was
>there and kinda annoying. I checked this on a friend's Zuiko 180mmf/2.8
>and it was there also. Other than that it was a fine lens.
>In comparison to the Nikkor 180mmf/2.8 (I shot with the manual focus AIS
>version for 6 years) I found the two lenses very comprable---except for
>that purple fringing on the Zuiko. The Zuiko 180mmf/2 blew both the
>f/2.8's away. Of course, so did the price.
>
>Jeff Horner
Tomoko Yamamoto
Photographer, Composer, Soprano
mailto:tomokoy@xxxxxxxxx
http://www.charm.net/~tomokoy/
-All the photos (except panorama) with OM's-
http://ep.com/ep/csp.html?csp=1130
-Olympus Equipment Classifieds-
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