Lens impurity

[PFrankyX]

Hi all, I have just bought my first SLR (Canon 550D) and bought a 2nd hand lens of eBay (EFS 17-85) in the past few weeks. It is under 12 months old and has local warranty, but I am hoping that this might be an easier fix than having to consider warranty.

I was taking some scenic shots of our lovely harbour on Friday night and noticed a lens impurity which was really ticking me off and am now very disappointed after just getting this equipment and is very frustrating as you may understand.

I have included an image for your reference. Now this mark on the bottom right corner only appears when I have used a slower shutter speed (more than 1"). It does not appear at faster speed. I have cleaned both the ends of the lens and the impurity still appears.



I hope someone can shed some light on what my options are here.

[Nicole]

I've deleted the duplicate of this thread, we ask that you don't cross post. Makes it easier for everyone.

Does the spot show up if you change lenses and use the same settings? My first guess would be dust on your sensor.

[PFrankyX]

Thanks, I only have one lens, so unable to check if it is the lens or not at this stage. That is one thing that I will no doubt try over the next few days, but just wanted to get some opinions.

[Nicole]

Yep, I'd definitely try another lens if you can get your hands on one. Perhaps go to a camera store and try one out with your own card in there.

Dust will show up more at small apertures (you were using f/29). Just something to keep in mind in diagnosing the problem.

[Thunder_o_b]

Looks like a dust bunny to me. Watch yourself cleaning the sensor, it only takes one wrong move to damage it, that being said, I cleaned mine four times last year. I change lenses often.

[RLucas]

You should be able to take the lens off, and point it toward a white wall or a light colored wall. and take a shot. If it still shows up, it is sensor dust.
Dust on the sensor shows up usually the farther away you focus as well.
That is what it looks like to me.

[PFrankyX]

Seemed to have fixed it. I believe it was dust on the sensor. Used a blower. Now not showing up anymore. Thanks all for your help.

[Thunder_o_b]

Cool, cheep, easy fix