Wait, what?

[Hollis]

Can someone help me out here. Its late and I am aimlessly cruising the 'bay and I found this (really, really want it too if anyone has one...)

http://cgi.ebay.com/Schneider-XENOTAR-150mm-f-2-8-4x5-camera-lens-on-LINHOF_W0QQitemZ130258542998QQihZ003QQcategoryZ15247QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


Anyways, I was reading the description and this stuck out...

he front element has a whisp of cleaning marks on the front element. rear element is clean and clear. It does not effect the final image. as you all know, the main function of the front element gathers the light and the rear element focuses everything

Is that true? I have never heard that before and in my mind, both front and rear are equally important. Clarify, please.

[Jon Wilson]

As you know it makes no sense.....plus the price is high....given this economy. Ahhhhh yes, the puffing of ebay....avoid the impulse purchase. :)

[Hollis]

Oh I know, I don't feel like sending my version of a bailout to someone on ebay. By the way, what is a good price for one of these???

[domenico Foschi]

Actually I think it might be right.
I am not an expert in the physics of optics but I have read it right in this forum.
Try to make a search.

[Skorzen]

I tend to think that is wrong... if nothing else how do you explain convertible lenses? How about Dagors and other symmetrical lenses? Bother elements focus light and are important to the function of the system. As to how much of a difference the cleaning marks in this example make I don't know.

[Ivan J. Eberle]

Umm... do you ever like to include the sun in the frame? Any mark on the front element (or even dust, or fingerprint smudges) will have a much greater tendency to flare. In most situations a cleaning mark won't matter; in backlight situations it can be crucial to have it pristine.

None of which may matter to you. But even so, are you sure this is really a 4x5 lens? There were any number of Xenotars commonly used on MF 6x6 TLRs... Too, the #2 Compur hasn't been made in quite awhile and there isn't a modern Copal equivalent AFAIK, so buyer beware. Get the seller to guarantee that it covers 4x5 at minimum.

[domenico Foschi]

http://www.largeformatphotography.info/forum/showthread.php?t=6737&highlight=image+forming+lens

[Frank Petronio]

that is not an unreasonable price for a 150 Xenotar...

[Bill_1856]

The Compur #2 is a PITA, because it has no "press focus" mode. To open the shutter for composing you must first move the dial to "T" and then after focusing move the dial back to the shutter speed you want.
The "Linhof" Compurs are particularly noxious because they have an extra faceplate making it more difficult to turn the dial (this one on ebay doesn't have that problem).
I'd love to have it, but I just washed my hair.

[J. Patric Dahlen]

The price is too high (for me!), and the "cleanings marks" would irritate me as long as I owned the lens.

[Nathan Potter]

Of course the front element gathers light but to say the rear element focuses it is a bit of simplification. All elements contribute in a variety of ways to produce a quality image. Sharp focus, spherical aberrations and color corrections are all maximized to the extent possible using the chosen optical element arrangement. Varying optical element lens thickness as a function of radial distance can be a first step in achromatism correction and varying the index of refraction of different elements can lead to superior color correction. Ideally employing aspheric elements gives the optical designer an additional tool for improved correction over a field of view.

What the heck, the lens defects you can tolerate depend on your financial resources as much as anything. Sometimes you can pick up a nice lens for a song because of minor defects and for most situations it will perform fine. As others have mentioned most defects of a minor nature will only scatter light reducing the contrast of the image on film. OTOH sometimes reduced contrast is a handy thing.

Nate Potter, Austin TX.

[Hollis]

Well, I don't do much shooting into the sun. In fact, I try to limit the amount that I shoot when the sun is actually out. Best case for me is heavy cloud cover or late evening light for my people work. I don't think that I am going to get it. I found out this morning that I was barely outbid on a casket set I was bidding on because I was asleep. If anyone on here got that one from austrailia, let me know how it shoots.

H.

[Jim Galli]

A "whisp of cleaning marks" could mean anything from 5 non intrusive sleaks to it had overspray and I cleaned it with a brillo pad and some Comet cleanser. My experience is that a few sleaks make no difference except what you might expect to pay, the brillo pad does! In any case his price is right for a lovely perfect or near one.

[Floyd Waller]

All of you guys need to try a little test that I used to employ on "prima donnas" worried about a few wisps on their lens. This will work on many types of cameras and lenses--while looking through the camera, ie. ground glass or viewfinder of smaller formats, have someone hold a pencil directly across the face of the lens and see if you can see that! I spent 30 years in camera retail and was always amused by people's paranoia of the tiniest flaw on the front surface of a lens. I once owned a Canon RF 50mm f1.8 that looked like it had Jim Galli's brillo pad taken to the whole surface and it took beautiful pictures. I had a lady customer who dropped her Canon AE-1 with 50mm F1.4 and lost a chip out of the front element the size of my pinkie nail and it continued to take great pictures! Once when we sold telescopes, I intentionally set one on a tripod with the front of the lens resting centered on an iron burglar bar in the window. People were amazed at the "X-RAY" vision of the telescope to see through the iron bar! I'm sure my friend, Lynn Jones, will vouch for this. Take a deep breath and get on with it!

[jnantz]

All of you guys need to try a little test that I used to employ on "prima donnas" worried about a few wisps on their lens. This will work on many types of cameras and lenses--while looking through the camera, ie. ground glass or viewfinder of smaller formats, have someone hold a pencil directly across the face of the lens and see if you can see that! I spent 30 years in camera retail and was always amused by people's paranoia of the tiniest flaw on the front surface of a lens. I once owned a Canon RF 50mm f1.8 that looked like it had Jim Galli's brillo pad taken to the whole surface and it took beautiful pictures. I had a lady customer who dropped her Canon AE-1 with 50mm F1.4 and lost a chip out of the front element the size of my pinkie nail and it continued to take great pictures! Once when we sold telescopes, I intentionally set one on a tripod with the front of the lens resting centered on an iron burglar bar in the window. People were amazed at the "X-RAY" vision of the telescope to see through the iron bar! I'm sure my friend, Lynn Jones, will vouch for this. Take a deep breath and get on with it!



i agree with you 100%

[C. D. Keth]

I worked with a director of photography who had a personal Cooke series II 100mm prime that he brought onto every job. Cooke series IIs were pretty state of the art when they were introduced in the early 60s but they're pretty soft by modern movie standards. That was his close-up lens and he loved it to death. I asked the first assistant camera (I was the 2nd AC) why he liked it so much and he showed me the front element. There was a chip about half the size of a dime in it, a little bit off-center, and it has been dulled with india ink to help flaring. The lens made beautiful pictures.

[Jeff Keller]

IC = 160mm (infinity @ f16)
http://www.schneideroptics.com/info/vintage_lens_data/large_format_lenses/xenotar/data/2,8-150mm.html

Jeff Keller