Zuiko 35-105 possibly with aspherical elements ?

Hi,<br><br>

this is a question for owners of Zuiko 35-105 f/3.5-4.5 push-pull zoom lens.<br><br>

Look at the optical construction of the lens below: (image linked from <a

href="http://www.mir.com.my/rb/photography/hardwares/classics/olympusom1n2/shared/zuiko/htmls/35105mm.htm">here</a>)<br>

<img

src="http://www.mir.com.my/rb/photography/hardwares/classics/olympusom1n2/shared/zuiko/images/35105mmf3545.gif">

<br><br>

I noticed that the 4th or 5th element (from the front) makes strange reflection.

Definitely different from reflection of all other elements. Take your time to

examine it further and then let me know what you think...<br><br>

I think it's an aspherical element. Could it really be or am I just dreaming

?<br><br>

(The lens was introduced in 1983/4 when the technology for aspherical lenses was

already available)

Take your time to examine it further and then let me know what you think...

I meant to say examine it further ON THE LENS, not on the drawing :-)

Hi,

I can not see your point. The aspherical lens technology in the 80ies was very different from the technology of todays consumer zoom lens. Then, a asperical element would only make sense on a high performance lens. Olympus would have pointed to this, why shouldn't they? If an inner surface reflects, the reflected light will bear abberations of the leading surfaces. That can lead to "strange" pattern. More simple, the reflection is a funktion of an angle, producing ring shaped pattern which could be regarded as aspherical. Last not least, the term aspherical (against Apochromatic) does not say anything about the lens performance and should be avoided.

Given the expense of grinding an aspherical surface in the early 80's (most are molded today), I'm 100% certain that Olympus would have trumpeted it in their promotional literature if it was true. The 35-105 was a nice lens, but hardly one of the stellar performers like the 35-80/2.8.

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