Chip on the lens' edge

[dimitrygo]

I got today Meyer-Optik Primoplan 58mm/f1.9 lens. It was described as having cloudy optics and therefore sold for 38.5 Euros. After I received it today I found the front lens has also a chip on its inner side. The chip protrudes about 1.5 mm from the edge and is well visible also when looking through the lens from the rear.

Now my question is how much does this influence the image quality? Since the lens anyway requires cleaning I cannot test it and decide looking at the images it produces. And I don't want to clean it without knowing what to expect from it. I have to say the external cosmetic of the lens is quite good.

Should I return the lens or try to ask for a partial refund (as I sayed this fault wasn't described in the auction)?

[dave_t]

From what I've read, chips/scratches in lenses primarily affect the contrast and flare control of lenses.

I recently found a fair sized scratch on one of my automatic lenses, about 1.5mm in length, near the middle. It doesn't seem to be doing too much, but I seem to be noticing an increase in flare activity, but it could just be the circumstances.

[exaklaus]

You should probably return it!
Or keep it on file for spare parts, as this Primoplan lenses are quite often in rough condition. So with another one, that might have some faults (and is cheap, too), you could probably get a nice one at a good price, finally.


Klaus

[visualopsins]

this sounds like a nice lens to keep and use. use black marker or paint fill chip after disassembly and cleaning. any effects will be most noticible in wide open oof highlights, which show even internal dust; blackened chip will show there, but it will be tiny. no effect when stopped down where light from chip part of lens is not used.

[Poolhall]

My Jupiter 37AM has a great big chip and crack on the side of one of the elements, you can plainly see it looking from the front yet it appears to have had no real effect on it- I certainly dont feel the need to take it apart. I would suggest you give it a go first, if its very poor send it back, if its ok then clean it and 'colour' it as sirius dogstar recommends. Sometimes damage looks far worse than it is

[no-X]

Chip 1.5mm near edge on fast lens? It will not affect anything, it's very likely out of the 36x24 frame. Imagine, that the lens projects image circle and only rectangular part of the projected circle is used by the film/sensor.

Many lenses also have bigger front element, than is needed for 36x24 format to prevent vignetting.

[dimitrygo]

[visualopsins]

Actually, only closing aperture will block light from the edge chip region.

For example, from a lamp or another subject in the center of the frame, light rays radiate from it to cover the entire front lens surface. The lens bends all of those rays onto the same place on sensor or film, the center. Thus light from chipped region reaches any size film/sensor. Closing aperture cuts off the outer rays, those from outer surface of lens.