[hanny]

i take every picture when using 17 i will appear something like dark or black at the four corner of the picture

what happen ??
<350d 20d 30d is the same > any one can tell me that is it normal

[ykszeto]

是不是裝了flter後再裝cpl呢？

[hktsoi]

一般廣角鏡都會有黑角，特別是1)超廣角、2)廣角Zoom、3)大光圈廣角、４）全開光圈拍攝。如果質素高的廣角黑角的程度會較低。Canon EFs 17-85中了1), 3),自然會見到黑角。要減低黑角，收細兩級光圈拍攝。

[hanny]

very thank you
because at first i put on a protect uv lens than i put more one cpl lens than i see a very serious black color on the cornor after remove all it still a little bit dark at the corner

but now you teach me to reduct the to try
so i think it will work

but any way thank you for all your help

[Obi-Wan]

Have u using a hood, according the the manual of 17-85IS, REMOVE the hood when using the CPL

[hanny]

i m using a hood when use a uv lens not useing a cpl lens

[hanny]

also after check the efs 10-22 is also the same with dark corner i think this is right that when useing a big f

and is the design bug of a wide lens because inside the size of the lens are very closely like the size of the cmos