Strange green line..

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bfitzgerald
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Strange green line..

Unread postby bfitzgerald » Wed Jan 02, 2013 4:49 pm

But only at certain angles


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Answers on a postcard please..

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pakodominguez
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Re: Strange green line..

Unread postby pakodominguez » Wed Jan 02, 2013 6:02 pm

I've seen those lines on screen only -never on the result image. And, like yours, where the highlight are. I guess is the mirror + lens combo...

harvey
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Re: Strange green line..

Unread postby harvey » Thu Jan 03, 2013 12:40 pm

Presumably converted from RAW? If so then does a different raw converter or higher quality jpeg
show the same line?

Harvey

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bfitzgerald
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Re: Strange green line..

Unread postby bfitzgerald » Thu Jan 03, 2013 1:23 pm

Shows up on both lenses (18-55mm and 17-35mm), also present on jpeg and raw (I just used IDC for convenience)
If I move the camera up and down the size of the line increases/decreases so I'll have to assume the SLT mirror is doing something here.
I have a small green bottle on the window sill and that's the only possible way I could see any green light of any kind getting into the camera
It must be hitting the mirror and doing something odd, very acute angle (the green bottle to the lens)

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pakodominguez
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Re: Strange green line..

Unread postby pakodominguez » Thu Jan 03, 2013 4:53 pm

Yeah, Mirror issue. What camera you got? the A57? I thought the second generation of SLT were better. Do you want to try another shot with a polarizer? How about your 50 f1.7?

There are some lenses, like the Minolta Macro 50mm f2.8, that reproduce an strange flare at close focus on backlighted scenes (due to the quality of the rear element of the lens, not specially optimized for digital)

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Dusty
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Re: Strange green line..

Unread postby Dusty » Thu Jan 03, 2013 7:27 pm

Strange green line? I always thought it was the "Thin Blue Line". :lol:

Tell me again Sony, why the SLT is so great?

Dusty
A couple of a350's, an a700 and now an a580, plus even more lenses.

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bfitzgerald
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Re: Strange green line..

Unread postby bfitzgerald » Thu Jan 03, 2013 9:29 pm

Maybe I should email Sony to tell them :mrgreen:
I'll try it with an OVF camera just to make sure

I should be getting paid for QC testing on cameras been doing it a while now!

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bakubo
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Re: Strange green line..

Unread postby bakubo » Thu Jan 03, 2013 9:48 pm

bfitzgerald wrote:I should be getting paid for QC testing on cameras been doing it a while now!


No, that won't happen. The business model for lots of companies these days is to get free testing by their paying customers.

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bfitzgerald
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Re: Strange green line..

Unread postby bfitzgerald » Thu Jan 03, 2013 11:33 pm

Have to agree esp with Pentax/Nikon, if this is just a weird happens very rarely issue then not a huge problem. I've not done enough field use with the A57 to know if there are any issues with the SLT mirror.

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bfitzgerald
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Re: Strange green line..

Unread postby bfitzgerald » Sat Jan 05, 2013 2:02 pm

I tried to reproduce the effect with the 2 Km5d's I have and I did not manage to do that even with the same position/lenses.
I removed the green bottle from the shelf, this was not the cause of the problem.

Shielding the light source from the window removed the green line.
I would have to say that this is caused with the light hitting the SLT mirror, changing lenses did not make any difference. This effect has not been noticed before in other shots, seems to be specific to some angles of light.

Some more examples, also tried the 50mm f1.7 same result

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David Kilpatrick
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Re: Strange green line..

Unread postby David Kilpatrick » Sun Jan 06, 2013 6:30 pm

It's not the SLT Barry, it is a sensor-produced artefact. Got to admit I've never seen such a bad example. The very bright (excessively) patch of light in the roof window is causing a readout error, line by line, from the CMOS, It will always appear as a horizontal patch, band or line relative to the sensor orientation and it will always match a large area of light.

Try positioning the light towards the other side (right hand side) of the shot instead of the left. You may or may not get the same effect (turn the camera upside down if need be to do this).

I've never seen this from a Sony sensor, but it was common in early Canon CMOS sensors. Bright lights saturating the pixel wells could cause an overspill and this could have a coloured bias - like a green band across blue sky.

What is different here is that the band looks darker, indicating something quite subtle is happening with the readout, like a stage getting oversaturated and somehow causing a deficit or compensation in the readout for that line. It may be that the brightness is so high it flips in some kind of protective action.

But looking at this, I'm pretty sure this is a sensor issue not an SLR mirror issue.

David

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bfitzgerald
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Re: Strange green line..

Unread postby bfitzgerald » Mon Jan 07, 2013 12:00 pm

Interesting thanks for the thoughts David.
Today it is overcast, but with still quite a large difference inside-outside, I had trouble trying to repeat this issue taking the same shots and again exposing aggressively for the shadows I didn't get a green line in any of the shots.

Bit puzzled, not really sure what to do about it (if anything) Obviously if it starts to show up in real world day to day shooting I will get it serviced.

Update:
I managed to get a another green line/s so I guess I will have to send it back to Sony (this means every DSLR I have bought since 2006 has had a problem of some sort, (1 x Km5d black frame, A200 returned twice dirty VF, K-x with mirror slap problem, K-r front focus, D90 x 3 back focus, D7000 x2 back focus, A57 apparent sensor problem) I find that staggeringly worrying.. :mrgreen:

Anyway here's a few more green line shots.

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mikehawthorne
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Re: Strange green line..

Unread postby mikehawthorne » Tue Jan 08, 2013 12:19 pm

i have seen this in the movie the omen!

mike hawthorne

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bfitzgerald
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Re: Strange green line..

Unread postby bfitzgerald » Tue Jan 22, 2013 4:52 pm

Quick update:
I contacted Sony support and explained the problem (as well as the level gauge issue which was not accurate in the vertical position shutter release button at the bottom)
They've advised me to send it in under warranty.

So today I posted that off with a letter explaining things and sample images on a CD
Will report back when I have more information.

I've not noted any other threads about this from Sony users so I have to assume I got unlucky here.

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bfitzgerald
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Re: Strange green line..

Unread postby bfitzgerald » Tue Apr 09, 2013 6:44 pm

By accident I came across this thread..

http://www.dpreview.com/forums/post/51245250

Interesting!


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