[Paul the Sunman]

I often notice streaking in the out-of-focus areas in shots taken with my SMC DA 55-300. It is always very regular and goes from top left to bottom right. You can see it in the green foliage at upper left and just to the right of the kangaroo's head in this shot (f/8, iso 200, 1/500).



Does anyone else find this with their copy? Any idea what causes it?

[BigMackCam]

Hi. Are you using a UV or other filter? If so, try taking it off and compare the results. I found that several of my UV filters gave a very similar effect. FYI, I have settled on Hoya HMC UV filters now, as I've yet to have one bad one...

Beautiful shot, by the way!

[Paul the Sunman]

What a good thought! That hadn't occurred to me. I have a Promaster MC-UV filter on that lens. I'll try some shots without it today.

Thanks.

[BigMackCam]

I'll bet you a cold pint that's the culprit I drove myself nuts with the same problem - straight lines in the bokeh - consistent in direction. I tested every filter I own, and now have a filter "hall of shame" in my camera cupboard

---------- Post added 08-23-2015 at 12:42 AM ----------

I just found my original post from when I ran into the problem. Thought you might find it useful

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/295252-alwa...r-filters.html

[Paul the Sunman]

Yes, that's it. Here's a shot sans filter:



and here it is with the Promaster MC-UV filter attached:



The out-of-focus foliage just to the left of centre shows clear streaks in the case with filter, but none at all without it.

I am very pleased to have that cleared up. Thanks BigMackCam!

[clackers]

and here it is with the Promaster MC-UV filter attached:

Throw it away, Paul ... it's a relic of the film era.

Your digital sensor has an anti UV layer built into it now.

[BigMackCam]

Yes, that's it.
...
The out-of-focus foliage just to the left of centre shows clear streaks in the case with filter, but none at all without it.

I am very pleased to have that cleared up. Thanks BigMackCam!

You're very welcome As I mentioned, I now use Hoya HMC UV filters on all of my lenses (for physical protection and cleaning convenience), and so far haven't come across a bad one. I recommend them.

[kev.pride]

Yes, that's it. Here's a shot sans filter:



and here it is with the Promaster MC-UV filter attached:



The out-of-focus foliage just to the left of centre shows clear streaks in the case with filter, but none at all without it.

I am very pleased to have that cleared up. Thanks BigMackCam!

Along with loss of quality in the image. Filters, unless you are using for effect are a total waste, offer little in protection and lens cleaning using a blower is all that anyone should need in most conditions.

Just my thoughts.

Kevin

[BigMackCam]

Along with loss of quality in the image. Filters, unless you are using for effect are a total waste, offer little in protection and lens cleaning using a blower is all that anyone should need in most conditions.

Just my thoughts.

Kevin

We photographers are polarised on filters, it seems (see what I did there? ). There are many times I've taken my camera to a windy, wet coastline and ended up with salty water, occasionally sand, on my UV filters. It's a whole lot easier, and less worrisome, for me to dust off sand and wipe off salt deposits from a filter than from the glass of a prized lens. Plus with the Hoya HMC UV(0) filters I'm now using, there are very, very few occasions where i've noticed any degradation in IQ (and I'm a dreadful pixel peeper! ). There's considerably more risk of flare, for sure - but I can remove the filters when required...

But, it's a personal preference, that's all...

[clackers]

It's a whole lot easier, and less worrisome, for me to dust off sand and wipe off salt deposits from a filter than from the glass of a prized lens.

Sure, just take it off before you touch the shutter release! :-)

[BigMackCam]

Sure, just take it off before you touch the shutter release! :-)

Ha ha One of these days - for those that care - I'm going to post some "with filter" / "without filter" shots to see who, if anyone, can reliably identify which is which, and why...