Dark circles around ourtside of scene

[PhotographyBuff]

I believe these may have been caused by usuing my polorizing filter however, it is on a stardard 17 - 70 mm lens which came with my Sony a350. My filter has an arrow on trhe top and perhaps it was turned. If I am correct how can I avoid this in future. If not any idea what caused them. It didn't happen on all my photos, only about 10%.
Tks for your help and Merry Christmas

[CBabcock]

The phenomena you describe is called "vignetting" and is the shadow of something that extends the lens barrel beyond the designed limits. When you do a wide angle shot (and 17mm is a good wide angle) you see the edges of the filter or lens hood.

[PhotographyBuff]

Originally Posted by CBabcock

The phenomena you describe is called "vignetting" and is the shadow of something that extends the lens barrel beyond the designed limits. When you do a wide angle shot (and 17mm is a good wide angle) you see the edges of the filter or lens hood.

Tks, is there anyway to avoid this and still be able to use the wide angle on this lens?
Rgds

[Digidave]

You either need to use a longer focal length or a thinner filter. There is no way around it.

[flytyer57]

I've had this problem occur with a CP. I used to adjust the filter turning it against the threads and it would literally unscrew itself from the lens and then stick out too far for the wide angle. The same thing could occur with a thick filter, or when stacking filters. Using the wrong lens hood could also cause this.

[Doug Sundseth]

Some simple things you can check:

If you're using both a CP and a clear or UV filter, lose the clear or UV filter. Stacked filters are thicker and more likely to cause vignetting.

If you're using a lens hood, make sure it is correctly and fully installed. A petal hood, if slightly short of being fully installed, can cause vignetting.

If it's neither of those, you can try a slim filter, which doesn't have threads for another filter.

Failing any of those, you probably won't be able to shoot with a filter without vignetting.

[PhotographyBuff]

Originally Posted by Doug Sundseth

Some simple things you can check:

If you're using both a CP and a clear or UV filter, lose the clear or UV filter. Stacked filters are thicker and more likely to cause vignetting.

If you're using a lens hood, make sure it is correctly and fully installed. A petal hood, if slightly short of being fully installed, can cause vignetting.

If it's neither of those, you can try a slim filter, which doesn't have threads for another filter.

Failing any of those, you probably won't be able to shoot with a filter without vignetting.

I would like to thank everyopne who replied. I now understand what causes the problem and will adjust for it n the future. PS I have lost the extra UV filter.
Rgds

[RobSPhotoNut]

As an aside to the vignetting problem, take a picture with and without the "lens protector" filter. I used to use them, and not the cheap ones either. After seeing the results, I use them for frisbees now. Yeah, that noticeable. Unless you really need more than one filter, can't see why on digital, try using step up rings with the larger filter over the lens.