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K30 - viewfinder alignment problems?

peterf
Posted 24/05/2014 - 15:10 Link
My old K10D used to have a problem whereby the image that the camera recorded wasn't what was in the viewfinder, it was rotated slightly, which I put down to a badly adjusted mirror.

However, my new K30 is doing the same thing, which I noticed this week while photographing graffiti on shop doorways. The alignment error seemed to change from one frame to another, sometimes it was a rotation error, sometimes it was a quite considerable horizontal shift. On a door way about 4 metres/yards away, I had to frame the shot about 40cm to the left in order for the actual image to align with what I wanted to capture.

I've ended up having to frame wider and manually edit the images, which defeats the object of having a 100% view in the viewfinder.

What's causing this? Is it the shake reduction?
Gravelrash
Posted 24/05/2014 - 15:25 Link
Shake reduction? Maybe. Sounds a bit extreme. I would expect you to be using a 28mm manual lens with SR configured to 135mm for it to be that extreme though!
Steve

Sometimes I'm serious and sometimes not, but I consider sarcasm an artform. Which is it today?
peterf
Posted 24/05/2014 - 15:59 Link
I'm using a Sigma 18-125 AF lens, the worst shot, described above, was taken at 22mm. The SR selection menu doesn't appear when I fit the lens so I can only presume it's correctly reading the focal length.

I just found an even worse image, taken at 36mm which I've attached below, resized by 25%. I was about 3 metres from the doorway, and in the viewfinder the central painted area was centred in the frame. There is some lens distortion but that doesn't explain why the image isn't centred.

Comment Image


I'll try some test shots with SR off and see what happens.
Gravelrash
Posted 24/05/2014 - 16:06 Link
Great pic, weird problem. I specifically mentioned manual because you can then override the SR effect, wrong aswell as right. As you say it will be auto on your lens.

Does this happen in RAW too? I only say that because jpg's can crop slightly differently and I've no other idea's. The chances of having the same problem on two different cameras would pretty much rule out a manufacturing problem.

Going to be very interested in hearing from someone who knows what they're talking about
Steve

Sometimes I'm serious and sometimes not, but I consider sarcasm an artform. Which is it today?
Gravelrash
Posted 24/05/2014 - 16:09 Link
Bit of a PS but could it be the in lens SR? or does it not feature on Pentax fit lenses?
Steve

Sometimes I'm serious and sometimes not, but I consider sarcasm an artform. Which is it today?
peterf
Posted 24/05/2014 - 16:18 Link
Hi, you are quite correct in saying this is a lens with built in SR in its Nikon and Canon versions but it's removed on the Pentax fit.
peterf
Posted 24/05/2014 - 16:21 Link
p.s. another clue is that normally I get no vignetting in the corners of images, but when the camera is showing the problem described, I also get vignetting in the top right corner, as you can see in the image above. That's not there on any correctly framed images.
Gravelrash
Posted 24/05/2014 - 16:24 Link
Does it work fine with other lenses? I'm guessing it's the lens that is in common with both cameras problems?
Steve

Sometimes I'm serious and sometimes not, but I consider sarcasm an artform. Which is it today?
peterf
Posted 24/05/2014 - 16:29 Link
p.p.s Not the same lens as I had on K10D, that was a Sigma 17-50 I think, something like that, and I sold that camera about 5 years ago.

The menu option to adjust focal length for SR is not available, greyed out.

However, I did find an interesting menu option (I find more features every time I look!) called Composition Adjustment which shifts the sensor horizontally, vertically and rotationally. I'm not really sure what use it is as you can't see through the viewfinder and check the composition at the same time, however by shifting the sensor I can easily get the kind of error that I originally described, so it must therefore be a SR problem where the sensor ends up somewhere other than dead centre when I press the shutter button.

I'm going to leave the SR off from now on and see what happens.

Thanks for the sanity check Gravelrash, and further contributions still very welcome from all.
Edited by peterf: 24/05/2014 - 16:30
gartmore
Posted 25/05/2014 - 10:54 Link
Do you wear glasses when using the camera?
Ken
“We must avoid however, snapping away, shooting quickly and without thought, overloading ourselves with unnecessary images that clutter our memory and diminish the clarity of the whole.” - Henri Cartier-Bresson -
JohnX
Posted 25/05/2014 - 11:45 Link
Could you take a couple of shots using LV, so we can see what the framing is like?

Wearing glasses wouldn't produce the vignetting Ken, but I'm intrigued by the fact that the only common factor in this is you Peter.
Smeggypants
Posted 25/05/2014 - 23:46 Link
Looking at the vignetting in one corner it looks like the sensor is misaligned with the image circle.

I'm not sure how much travel the sensor has in the X and Y plane but the solenoids should hold it central and it looks liek that isn't happening?

when you get conditions when the problem occurs try taking a pic at all four rotions of the camera i.e landscape and portait both the right way up and upsode down. If the vignetting stays in the same place relative the camera then the sensor is being held in the wrong place. if it mvoes the sensor might be sliding around, not being held at all.
[i]Bodies: 1x K-5IIs, 2x K-5, Sony TX-5, Nokia 808
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283

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