Broken glass how impact picture quality.

[Attila]

This lens is one of my lenses who in worst shape. I bought 10 pcs in batch half of them was okay. Try to guess what kind of result I will get I never tried out yet how impact picture quality.

[LucisPictor]

Looking at this lens really hurts!!

Since the rear element is broken I guess that it will have a considerable influence on image quality!

[Attila]

[fatdeeman]

I would expect lower contrast, reduced sharpness, very out of focus highlights that become discs might have the shape of the crack showing up in them as a dark shadow but it won't affect in focus areas.

Probably nowhere near as bad as anyone will expect though!

The only thing I'm thinking is that the worst damage is at the back so might have a more severe effect.

Those are my wild guesses!

[NikonD]

OUCH!

[visualopsins]

Focus may vary across frame if last element is knocked out of alignment; might be obvious 'line' where focus changes, in same orientation as crack line (inverted on image).

Chip effectively blocking light reduces lens max aperture; chip should be invisible if aperture is closed past where chip is inside projected image circle.

In wide open out-of-focus bokeh highlights all dust scratch chip will be seen.

[egidio]

this lens was probably used in vietnam war

[hinnerker]

i would say, the lens will do fine pictures after all.

I have seen lots of heavy used lenses in my career as a Pro photograph from my collegues. scratches on front and rear glasses, deep cracks and so one... mostly nothing affects the picture quality seriously, if the glass kept mechanical in place and the cemented elements are not broken/separated..

Only very small areas showing smaller contrast or CA in picture.. not more.

Cheers
Henry

[edz]

Having seen this page http://kurtmunger.com/dirty_lens_articleid35.html I guess the stuff on the front won't make much difference apart from reduced contrast and sharpness. The big crack on the rear element looks more serious though I guess it will probably be visible in the photo as a thinnish out of focus line for the crack and a out of focus low contrast blob for the chip. Might be worse if the element has been knocked out of position. Will probably look a lot worse if there is a strong light source in the photo.

What's the other stuff on the rear element, are they scratches too? Looks like someone was trying to clean it with some wire wool.

[Screamin Scott]

Take some shots & post them !!

[Attila]

[Screamin Scott]

I have a couple of lenses with small scratches on the front elements & other than a slight loss of contrast, I see no other detrimental effects (I rarely shoot with a light source near the frame so I can't make any observations there). The fact that I shoot with a DX camera & that most of the scratches are toward the edge of the lens, the effect is even less. I only have one lens with a severe scratch & that is at the edge of the lens. No detrimental effects noted with that lens either...

[fatdeeman]

I always prefer to have a lens that is free from scratches and fungus but in reality it usually makes very little difference until the damage is really bad.

I have a vivitar 75-205 and something has leaked right across one of the inner elements and it only shows up as a shadow in the shape of the dried liquid on oof highlights and even then it's only when you are taking a close up and the background is REALLY out of focus.

I bought two tamron zooms as part of a job lot and both have large scratches on the front elements but I can't notice any difference in the photos unless the sun is in frame which causes more flare than usual.

I also have a tokina 80-200 that has some fungus on several elements and I cannot see any effects even on oof highlights.

Obviously this lens is very bad but it might give surprising results.

[lorriman]

Ken Rockwell's tip for scratched front elements it to fill the scratch with black marker pen.

I rather think a severely cracked rear element is lens death.

[Screamin Scott]

Don't use a black marker, use "India Ink"

[Bruce]

ouch!

[djmike]

[Orio]

WIth the kind of damage on the rear glass, I expect detrimental effects on the images at all apertures and situations, but especially stopped down and in backlight.

[kansalliskala]

[Attila]

Image quality is quite effected no matter at which aperture result look like this. Click on to get high resolution image.

[Screamin Scott]

Bummer...

[kansalliskala]

Try cover the crack and see if there is some effect?

EDIT: actually take off the rear element, cover the crack from front and put it back?

[Attila]

[egidio]

now you have cheap softfocus lens like this http://www.the-digital-picture.com/Reviews/Canon-EF-135mm-f-2.8-with-Softfocus-Lens-Review.aspx

[Attila]