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05/14/2010 09:18:54 AM · #1 |
These two images are taken with a friends lens as the images she was taking at college were quite "cloudy". I put the lens on my camera and had the same results. I cleaned the front and rear element of the lens and when I took a pic with another lens it was fine. It is much worse at 70mm than 28mm. Any idea what could cause this?
 
This is a pic I took with the same lighting using my 85mm
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05/14/2010 09:50:13 AM · #2 |
I wondered what "couldy" meant! :-)
I don't know what could cause that, I thought it was just over-exposure. |
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05/14/2010 12:42:18 PM · #3 |
Bad or no coating on interior elements, and inferior glass quality, can result in a significant loss of contrast via diffraction of light rays within the body of the lens. That's what this looks like. This kind of stuff used to be a lot more common before we got low-dispersion glass and multicoating of elements.
That's my guess, anyway. That's really low contrast there.
R.
ETA; the problem's always going to be more extreme in backlit or bright-background situations, which is what you have here.
Message edited by author 2010-05-14 12:43:25.
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05/17/2010 11:12:21 AM · #4 |
| Thanks Bear ... that would also explain why the shots she has been taking out of the studio look ok. |
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11/23/2010 10:48:28 PM · #5 |
Any reason why you chose to overexpose the Sigma shots by 2/3 stop?
Hard to compare the results when they're shot at different settings.
bazz. |
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