[kcobain1992]

Hi, I have tested my girfriend's father's tele lens, and it seems very soft in the corners, soft also in the center, and it gives the photos an unpleasant gray appearance. Is this how all of these lenses perform?

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Last edited by kcobain1992; 09-20-2012 at 03:50 PM.

[Ikarus]

I wouldn't be able to tell from these examples. The only part in focus in the first picture is the center. In the second one, only the bottom is. There is also some flare in the first, which would be expected, if you didn't use a hood.

[kcobain1992]

So I just need to learn to use it? Maybe you're right. Will try it out more tomorrow.

[JohnBee]

Is this how all of these lenses perform?

I would say no.
But without seeing the full size images, its very hard to draw any sound conclusions at this stage.

[mikharPF]

Very sharp lens. If she is healthy)

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[VaSA]

Is that an export variant (Jupiter 37A) or domestic (Юпитер 37А). If its the latter than I wouldn't be surprised if its a bad copy because USSR put up the best stuff for export.

The second photo seems sharp though, its just that you did not focus on the pigeon but on the ground.

[jane7l]

ciao

i do not know why people ask about unsharp pictures and then post them without exif... anyway i think your problem is misfocus. the pigeon is definitely focused front, cobblestone is sharp.

[Laurentiu Cristofor]

Use a hood and work on the focusing.

Also, if you can, avoid shooting towards the sun - both your shots are facing the sun. Russian lenses are vulnerable to flare, but if you avoid those conditions (i.e. facing strong light sources), they will give you very good results.

[mzavalny]

Объектив достаточно резкий:

[kcobain1992]

Sorry but I concluded that it's unusable. Even with a hood and live view focusing, it simply wouldn't get sharp even at f/16. I guess I'll be searching for a longer tele anyway.

[Laurentiu Cristofor]

I have some images from my Jupiter here.

Yours doesn't look defective, but it would be great if you could post more images from it, to see if if the problem is with the lens, light conditions, or the focusing. Do you do the live view focusing handheld or on a tripod?

[kcobain1992]

Well I admit I only tested it handheld, but the resulted pictures were so bad that I deleted them immediately. I will do some more these days, but let me know what kind of subject would be best suited to demonstrate its sharpness.

[Laurentiu Cristofor]

You can try the classic test - a page of printed text, photographed at an angle. That lets you see which area is in focus and how sharp the lens is in the focal plane.

[JohnBee]

PS. the bird(pigeon) isn't close to being focused.

Looking at the ground, you can see things "getting" into focus as it nears the bottom of the screen. But even at that, you're not even close.

Based on this, I'd guess the same is happening with the first image as well.

[kcobain1992]

OP here. I took the lens out again today, gave it another chance to see if it really is faulty, and my conclusion is that it obviously is. Took two pictures, one at f/3.5 and one at f/11, focus double-checked with split prism, and they still look very fuzzy. I deleted the one at f/3.5, it was that bad. I will attach the other one, I'm pretty sure there must be something optically wrong with the lens, so I dismantled it. The problem is that I don't know what could possibly be wrong with it it has no fungus, signs of separation or dust inside, but can the optical elements be misaligned? I see that some screws had been previously forced, so obviously somebody else played with it before. I don't have a lens spanner at the moment, but I will acquire one if there is something I can do to save the lens. Thanks!