What happened to this lens?

[AntonioC]

Hi everybody,

 

I came across this lens, an O-Nikkor 35mm f/2, since I needed a

moderately fast mf lens for my Nikkormat.<br>

It is *nearly* perfect, but for a rainbow-like effect on the borders

of an inner element.<br>

Front view is visible in <a

href="http://www.photo.net/users/Carrus/DSC_6118.jpg">this</a> image.

Actually, it is transparent when seen across. I think it's some kind

of de-cementing.<br>

I was rather skeptical when I first tried to check it with a D100,

but the first <a

href="http://www.photo.net/users/Carrus/DSC_6113.jpg">test shot</a>

was not so flawed, at least it seems so to me (I'm speaking of the

full resolution image).<br>

I think the real test will be in high-contrast, sunny, backlit

images, but hope it will be usable in black and white (which is all I

need by this lens), maybe with some additional "Nikon glow" :-)

What is it, in your opinion?<br> Should I just throw it away?<br>

BTW, I paid 25$ for it.<br>

Cheers,<br>

<br>

Antonio

[AntonioC]

Forgot to say, the shot was at full aperture.

[arnabdas]

See <a href="http://www.photo.net/photo/2786022">this photo</a> by Mike Kovacs. Looks like an edge separation problem to me.

[peter_evans4]

I'm not quite sure I understand the logic: you buy the lens cheaply, you

try it out, you can't see anything wrong. In your place, I'd be happy -- but

no, you ask if you should throw it away. OK, OK, please help the sluggish

economy here in Japan: throw it out and buy a new replacement. Yes,

while you're about it, chuck out the Nikkormat as well!

[AntonioC]

eheheh... <br>

Actually the question was not so clear (not that I'm clear usually).<br>

I'm going to keep it, of course, I was just curios to know if someone else ever had the same problem, and what can be the limits of such a defect, since I wasn't able to detect them, and there's no way to have a sunny day here in this period.<br>

Or maybe the lens will self-destroy in two weeks, I dunno.<br>

Anyway, you're right ;-)<br>

BTW, thanks Arnab<br>

[akira_sasaki1]

Seems like you're right in that cemented elements are separating. Nikon might be able to repair it, maybe? Might not be worth the price. (I think you'd help the economy more by getting it repaired. :) )

[david_kelly1]

Not sure what you mean by "it is transparent when seen across."

Anyway, what your frontal shot shows is pretty minor compared

to what's happened to the Sonnar: maybe a little very incipient

seperation of the rear element. If you're curious about the worst

case effect you could create your own backit-on-a-sunny-day

shot using a couple of photofloods.

[dan_long]

Antonio:

I can't say for sure without seeing either more photos, or the lens firsthand, but I do notice that the slight reflection falling on the front elements (green coating) in the front is on the right side of the photo, and that these seem to be in line with reflections falling on the inner elements on the left and in the area in question. Is it possible that the rather pinkish reflections in question are an illumination of the coating of the inner element that is a different color than that of the outer elemnent, and that the less than uniform illumination might make one suspect the coloration to be only on the edges? If your Nikkor had de-lamination of the elements as shown in the picture of the german lens, I'm guessing you'd see an effect in the final photo, but you do not, so I would suspect you are seeing some of the lens coating. Again, this is with only one photo to go by and some conjecture.

 

regards,

Dan

[kelly_flanigan1]

The Nikkor-O 35mm f/2 stems from the 1960's. It is a single coated lens. This lens was hard to make in production; and results will vary from serial number to serial number. Some of the serial number blocks were orphans; not factory AI upgradeable. I bought one of these orphans in the late 1970's for 30 bucks. Mine is very good wide open; better at F2.8; and extremely sharp/best at F4 to F5.6 in the center. The production variation of the 35mm F2 was known in the late 1960's. Some folks would shot test images with several serial numbers; in a store; and buy the best one. A lens that is unknown; and old may have more problems. What matters if the lens works for your application. My lens is the sharpest 35mm lens I have.

[mskovacs]

Place your eye at the point of the film plane. Stop down the aperture until you cannot see the separation. I'll bet its completely gone before f/2.8.

 

Believe it or not, that Sonnar photo that I put up shows no ill effects that I can detect on film by f/2. It seems a little flarey wide open with lower contrast than f/2 but even a perfect specimen will show this to some degree in a Sonnar. I have another w/o separation that is actually slightly less sharp! The Jupiter 8M is also less sharp by a hair but also doesn't have as nice OoF areas and the 12 blade aperture of the Sonnar.

 

Getting the element recemented would not be cheap. John van Stelton quoted me $300 for that Sonnar. The price was double the normal rate though because the Sonnar has two cemented triplets, not doublets, hence double the work to recement the separated triplet.

[AntonioC]

Thank you very much for your inputs.<br>

It seems to be a relatively late unit,O C nr. 851xxx, so it should be a '74 lens, and optical performance is really OK.<br>

What to say, I'm *quite* happy (I'm going to keep it like this, not even interested in the ai conversion).<br>

Thanks again!<br><br>

 

Antonio