How good is the 150mm f2.8 Xenotar

[Vick Ko]

How good is the 150mm f2.8 Xenotar?

I may be getting one.

Are there any warnings on the lens (yellowing, Schneideritis)?

Thanks

Vick

[Michael Graves]

I've got an older Xenotar in a dial-set shutter. It's sharp enough, but only covers 4x5 with room for minimal movements. It's also subject to flare. But if you shoot most straigh on, as in landscapes, do work closer than infinity and guard agains stray light hitting the lens, you can get good shots with it.

[Thomas Vaehrmann]

Hi Vick,

once I had a 3,5/135mm Xenotar. It was/is an excellent lens, with good sharpness even wide opend. I dropped it because it's lenses are made of radioactive glasses (thorium) and I didn't want to keep it in the house with my family. Hot lenses get yellow, like some Summicron, Repro-Claron, Quinon do.

kind regards

Thomas

[Charles Hohenstein]

Hi Vick,

once I had a 3,5/135mm Xenotar. It was/is an excellent lens, with good sharpness even wide opend. I dropped it because it's lenses are made of radioactive glasses (thorium) and I didn't want to keep it in the house with my family. Hot lenses get yellow, like some Summicron, Repro-Claron, Quinon do.

kind regards

Thomas

Hey, think of it as getting a free yellow filter.

[Ernest Purdum]

I used to have one which I regarded as a specialized item, very worthwhile for portrait work. The extra speed was great for selective focusing. Mine didn't have yellowing. My impression is that the radiation from thorium glass is extremely low even as compared to the backgound radiation we all get every day. If this is wrong, someone please correct me.

On the other hand, the lens was large and heavy and had no particular virtues as a general-purpose lens. Since I wasn't doing much portrait work, I sold it.

[Jason Greenberg Motamedi]

In my obervation 135/3.5 Xenotars from the early 1950s often have a yellowing problem. I have never seen a 150/2.8 with tanned glass.

One thing to look for are patches of faint discoloration between elements. I had a 150/2.8 Xenotar which had a bit of something between the elements. I sent it to John Van Stelton of Focal Point. He suggested that "moisture settled on the glass and caused a corrosion due to the heavy metal content of that cemented doublet and water". Fortunately he was able to removed the stain. I have seen this in several other Xenotars and even in a Japanese Xenotar-clone, so it may be relatively common.

In any case, Xenotars are a bit soft and prone to flair wide open. Stopped down a stop or two they quickly become very sharp.

As Ernest pointed out, they are very specialized lenses are are really quite useless as a general-purpose lens. At f5.6 and beyond I think you will find that a multi-coated Plasmat will be just as sharp (if not sharper), less prone to flair, significantly smaller, and of course will be much cheaper. So, if you don't HAVE to shoot faster than f5.6 buy yourself a plasmat. On the other hand, if you need a very fast relatively sharp lens, there is nothing like it.

[wmjaeger]

These are old posts I'm responding to but I have both the 150mm and the 135mm Xenotars in terrific condition and wanted to give a couple comments:

1) Sharpness. Both are fabulous. Sharp as can be. There is a sense not of flare in common use but of less contrast than say the Symmar or the incredible Sironar-S. Now that I scan everything for printing, this is not a problem, a weird digital advance on old technology.

2) Flare. Yes. Like it or not. They aren't multi-coated. That's the bottom line. Supposedly Zeiss makes the equivalent Planar at f/2.8 with multicoating for a lot of money.

3) Radioactivity. Yes, many or these have thorium glass, and thorium is radioactive. But unless you ingest it, the alpha particles that thorium emits only go 1mm into the skin. If you hold the glass against it. Not a huge problem in normal life.

4) Coverage. Limited. If you shoot at something closer than infinity, like portraits or still lifes, you'll find decent movement. Enough for normal shooting.

[Lynn Jones]

i used the Xwnotar 150 f2.8 often in the mid 1950/s and wish I had one today, it was a wonderful very sharp lens. Dr. Kingslake says it showed up after WWII and probably was a development from the English Wray company and designer Wynne.

Lynn

[Carsten Wolff]

This may well be an apples for oranges answer, but I picked up a Komura 152mm f3.5 (also came as f2.8) recently; It seems at least as good as my old 135mm f3.5 Xenotar; (paid $149 for it in Copal 1; has a bit of separation, but fine).
Might be an alternative lens coice; I also agree with Michael, Jason, wmjaeger and Lynn.

[Jason Greenberg Motamedi]

Rereading my post, more than three and half years after I wrote it, I have a one correction:

Some early 150/2.8 Xenotar lenses were made with some sort of radioactive glass and do show the same staining as the 135/3.5 Xenotar lenses. This staining is nowhere near as dark as that of the Aero-Ektars, but it does effect both exposure and color balance. I am not sure when they were redesigned.