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Thomp
14-06-2010, 7:42pm
Recently bought a Sigma 10-20. So I took it out for a test run the other day, managed to get about a 100 shots or so. Processed a few back home and I noticed that one had a few weird lines running across the corner of the photo.

Apart from that I think its performing well, sharpness and focus seem to be good. There is some CA and very slight vignetting but from what I hear that is fairly normal.

But back to my point...anyone have experience with something like this? is it something to worry about? I mean it only occurred in a single shot so it could just be a one off.

Thanks

http://farm5.static.flickr.com/4010/4699486784_d671503e50.jpg

ricktas
14-06-2010, 7:51pm
Is this a crop, can we see the entire photo please?

arthurking83
14-06-2010, 9:54pm
As Rick asked.. if it;s a crop we need to see an entire shot.

If it's not a crop, why are you shooting at blue skies!? :p

I'm 99.9% sure that this will not be caused by the lens, for one main reason. Distortion(or the lack of it)

if there's a problem with the lens and you're seeing lines because of it, then there would be a good chance that those lines would be distorted by the lenses optic system, and the Siggy 10-20 has a kind of moustache distortion(or wavy shaped distortion), not just regular barrel type.

How deep into the corner are the lines?
They do seem to have a very slight divergent path relative to each other, so it;s most likely not a sensor issue.
Maybe some kind of internal reflection for the scene at the time?

if it ever happens again, I'd be worried about it. If it's a one off thing, then I wouldn't.

Thomp
15-06-2010, 1:20am
Thanks for the replies guys. I'm relieved to hear its most likely not a lens issue, Arthur! At first I thought it was some kind of super weird lens flare but it just seems to pop out from nowhere.

Heres the full photo, the lines are near the top right corner, they seem to just occur from the top of the cliff.

http://farm5.static.flickr.com/4045/4699594323_af63a6f361_b.jpg

arthurking83
15-06-2010, 6:17am
whoa! that is weird.

:confused013

ricktas
15-06-2010, 6:31am
This might sound like a really stupid question but are the high tensile power-lines running over the area, and you just did not notice them with your naked eye?

Dylan & Marianne
15-06-2010, 6:38am
they look like power lines ......weirdness indeed if they're not

arthurking83
15-06-2010, 6:41am
Of course that's the first thing I thought to ask too, but the OP said they only appeared in one image(and I assumed there are more of this image), and therefore the lines are an anomaly.

The spacings between the lines are a bit uneven(power lines will almost always be evenly spaced, and also they're dead straight(with no sagging bow effect).. powerlines also sag and produce a less than perfectly straight edge.

ricktas
15-06-2010, 6:43am
The real test would be to go out today, and take some more photos, of blue sky, using the same settings you used for the above, and see if the lines are visible in all photos. But looking at the crop and the full photo, I really believe you have photographed some power lines.

Gavvvvvin
15-06-2010, 8:03am
If they are not powerlines its pretty convienient they happen to stop just as they get behind the shrub lol.

Thomp
15-06-2010, 10:20am
Haha boy would I look silly if they turned out to be power lines! The way they are heading is straight over another cliff edge into the Jamison Valley, so I don't think they could be or I should have noticed something. Plus they seem to be rather vertical for powerlines?

I'm going to try taking some more photos today and see what happens.

So uhh, anyone heading down to katoomba falls want to check for me:p?

David
15-06-2010, 10:26am
Mate the best thing is to take the lens to another site and see if it happens again after you give it a quick clean and/or try another lens with the same shot sortof and see if it happens again.see u at the falls :D My Siggy 10-20mm never did that when I had one.

Thomp
15-06-2010, 11:05am
Well 74 shot later just outside and I don't seem to be getting any weird lines, tried taking shots using the same settings and similar conditions... seems to be a one off...I'm convinced they can't be powerlines! But I might just have to go back to check sometime to make sure I'm not losing it:o

Thanks all

darkbhudda
15-06-2010, 11:23am
Looks more like a flying fox or rappelling/climbing lines to me. Probably ninjas in training if it's only in one photo.

Any chance the camera could have just bokehed them out - not sure if there is a better term for this - in other photos?

dbax
15-06-2010, 11:41am
mmm look like something man made to me, Jamieson valley, I don't know the area but isn't there a cable car that goes across that area somewhere?

Ionica
15-06-2010, 12:00pm
They are the cables for the 'Skyway' that crosses from the Scenic Railway site.

Ionica
15-06-2010, 12:06pm
Well 74 shot later just outside and I don't seem to be getting any weird lines, tried taking shots using the same settings and similar conditions... seems to be a one off...I'm convinced they can't be powerlines! But I might just have to go back to check sometime to make sure I'm not losing it:o

Thanks all
They are the cables for the 'Skyway', which leaves from the Scenic Railway site.

Thomp
15-06-2010, 12:11pm
Well guys, it would seem those who mentioned the cable car/scenic skyway might be right! I just saw a photo on flickr of the skyway just above katoomba falls:o It would also explain why the cables are so straight.

:Doh:

Mystery solved :D

I need to go get my eyes checked.

Also thanks Ionica for confiming that.

stoogest
15-06-2010, 8:41pm
Classic thread!! Love it!

joeyvaldezjr
15-06-2010, 9:30pm
I also think those are high-tension cables sir.

Ionica
21-06-2010, 3:36pm
Well guys, it would seem those who mentioned the cable car/scenic skyway might be right! I just saw a photo on flickr of the skyway just above katoomba falls:o It would also explain why the cables are so straight.

:Doh:

Mystery solved :D

I need to go get my eyes checked.

Also thanks Ionica for confiming that.
View of Katoomba Falls and the Skyway. http://i1046.photobucket.com/albums/b461/Pentedatillo/sized_KatoombaFallsandSkywaycopy.jpg

dbax
21-06-2010, 8:56pm
yep it all makes sense now, I knew there was a cable car there somewhere, but my specific local knowledge good enough to take a definite stab at it.
Nice background shot Ionica:th3::th3: