01-15-2012, 05:53 PM
[quote name='photonius' timestamp='1326633685' post='14880']
that sounds more like the sigma lens has some miscalibration or even hardware issue, the f-stop not closing down to f8 as it should, maybe only to f5.6.
If you increase ISO, so that you can use faster shutter speeds, does the effect get worse?? (In case the mechanical shutter of the Sigma does not close fast enough - an unlikely scenario, but the above test is easy).
[/quote]
I do not have the lense with me rigth now, but I'll do that test as soon as I get home
Thanks
and thank to all the other
that sounds more like the sigma lens has some miscalibration or even hardware issue, the f-stop not closing down to f8 as it should, maybe only to f5.6.
If you increase ISO, so that you can use faster shutter speeds, does the effect get worse?? (In case the mechanical shutter of the Sigma does not close fast enough - an unlikely scenario, but the above test is easy).
[/quote]
I do not have the lense with me rigth now, but I'll do that test as soon as I get home
Thanks
and thank to all the other