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lichtloper
25th April 2010, 09:32 PM
What's wrong? I cannot say for sure.

Today I took a picture of what I believe are called braces or cramp-irons on a wall of a castle [the one on the left of two letters E entwined, and the other brace in the shape of an S].

hardware: E-620 + 14-54ii

I used the viewfinder and I intentionally aligned the bricks and windows with the upper and lower edges of the frame to avoid slanted lines as much as possible.
I took several frames, but they all seem to suffer from an awkward kind of distortion. The window on the right seems to sit lower than the one on the left and even lower than the one in the middle. The difference is small but well visible.
The three windows at the top of the frame all seem more or less in parallel with the upper edge of the frame - just as I wanted them to be.
I made several attemps with the same result.

At one time I began to doubt my judgment, so I put the camera into the bag, walked around for a bit, and then I retried.
Result: 'distortion' again.

Next I used the LCD screen to take the picture.
Guess what? NO distortion whatsoever!

http://e-group.uk.net/forum/picture.php?albumid=81&pictureid=332

I've drawn two white horizontal lines to make the problem visible.


Mirror out of alignment? Don't think so...
Sensor out of alignment? Unlikely...
Prism out of alignment? Maybe...

Does it sound familiar to anyone?


I've been useing the E-620 for about five weeks now.
I noticed the problem before, and didn't pay much attention; but I never took a photo that needed such an exact parallel composition like this one today.

Home again I did some tests (straight lined objects, walls, door) with the same result:
There's something wrong in the lower right corner of the frame.

EXIF:
ExposureTime - 1/400 seconds
FNumber - 7.10
ExposureProgram - Aperture priority
ISOSpeedRatings - 200
ExifVersion - 0221
DateTimeOriginal - 2010:04:24 14:14:03
DateTimeDigitized - 2010:04:24 14:14:03
ComponentsConfiguration - YCbCr
ExposureBiasValue - 0.00
MaxApertureValue - F 2.80
MeteringMode - Multi-segment
LightSource - Auto
FocalLength - 54 mm
ColorSpace - sRGB
ExifImageWidth - 4032
ExifImageHeight - 3024
ExposureMode - Auto
White Balance - Manual
Contrast - Soft
Saturation - Low
Sharpness - Soft
So nothing out of the ordinary in the EXIFdepartment.

lichtloper

wanderer
26th April 2010, 11:47 AM
I've done a fair amount of building photography including rectifying photographs to fit with drawings.

Looking at your photo, the centre of the picture appears to be about 2m above and 2m to the left of the camera position. The brick courses are falling away at bottom left too.
Although you have rightly used the long focal length of the lens to reduce distortion due to parallax, if the camera is not set up to be horizontal (I use a bubble level on the hot shoe) and at right angles to the facade you will get some distortion.
I would not use the brick courses to set the camera horizontal as experience shows that older buildings tend to settle and are often not 'straight'.

a couple of solutions;
1. Get a scaffolding tower to get yourself up to the same level as the cramps, probably not possible unless you are working on the building.:D
2. Position yourself directly below the mid point between the cramps, set the camera up horizontal and at right angles to the building, angle the camera back and giving yourself plenty of view on either side of the cramps take the photograph. In Photoshop use the image/transform commands to 'shift' the picture back to orthogonal.

Hope this is helpful.
Duncan

lichtloper
26th April 2010, 09:23 PM
Hi Wanderer, thanks for your comments and thoughts.
You're right to say that brick walls often aren't dead straight; the castle's walls certainly weren't.
It's too far a bicycle ride for now to revisit the castle, so I did some quick testing, useing a tripod; next time I will also use a bubble level, like you suggested.
Took some shots of the garden fence, results confirmed my fear:
the photographs taken with the viewfinder -which I prefer to use- show more distortion than the ones taken with the LCD; the recorded image is 'banked' a few degrees clockwise compared to the image That I saw through the finder.

http://e-group.uk.net/forum/picture.php?albumid=81&pictureid=336
btw I do not understand the diffence in exposure between these shots...
http://e-group.uk.net/forum/picture.php?albumid=81&pictureid=338

The test shots aren't perfect yet, I know, but I do know for sure that something is wrong with the viewfinder image. I'm going to do more tests, as I want clear and undisputable 'evidence' for when I'll go back to the shop.

lichtloper

Ross the fiddler
27th April 2010, 12:01 AM
Remember that live is showing you a 100% view while the viewfinder is only showing you 95% which makes a difference for an accurate allignment. Were you holding the lens diffrerently for each, because it may give you some tilt appearance if the extended lens is moving & does it do the same at 14mm? It is also possible there is a misallignment in the viewfinder mirrior path which may need warranty attention. I did hear of one being out.
Ross

Dave_T
27th April 2010, 11:17 AM
Phew, I've been having the same (or similar) problem but thought it was just me...a lot of the time my photo's seem to be rotated by a couple of degrees although I'm certain that it was correct at the time of taking the picture.

Interestingly I have an E600 (aka E620 lite) and also prefer to use the viewfinder for most of my shots.

My solution has been to re-align the shots during PP so it's not a lot of hassle, but I will now also try a comparison of viewfinder vs live view.

Maybe I'm not going mad after all!

Kiwi Paul
27th April 2010, 03:17 PM
The E3's are notorious for viewfinder tilt, mine was fixed recently. I used to compensate by tilting the camera slightly when taking shots through the viewfinder it's great now it has been fixed.

Paul

lichtloper
27th April 2010, 07:44 PM
Hi Ross, Paul, Dave,
Thanks for taking an interest in the problem reported.
Your replies have convinced me that even though my test shots weren't 100% OK, it's this camera which has a viewfinder failure.

I shall have to bring it back to the shop for repair.

I only fear though that it will be away for a considerable time, as Olympus DSLRs are sent to Portugal... - that's what the guy in the shop said to me when I asked what would be the procedure in case of repair.

Funnily enough -or better: not so funny- I had a similar problem before, twenty years ago a Contax 167MT body showed a very slight misalignment of the mirror; in the case of my E-620 I suspect the prism is dislodged.

lichtloper

The walnut in my garden getting fresh leaves:
http://e-group.uk.net/forum/picture.php?albumid=81&pictureid=339

lichtloper
27th April 2010, 09:07 PM
Hi Wanderer,

Made a few 'repairs' in CS3:
filter > distort > lens correction

This is my favourite procedure for Crooked House cases

lichtloper

http://e-group.uk.net/forum/picture.php?albumid=81&pictureid=340

Dave_T
28th April 2010, 11:18 AM
Hi Wanderer,

Made a few 'repairs' in CS3:
filter > distort > lens correction

This is my favourite procedure for Crooked House cases

lichtloper

http://e-group.uk.net/forum/picture.php?albumid=81&pictureid=340

This is similar to my workaround for these cases, I have just bought Elements 8 so that I can do this kind of correction!

mlc
28th April 2010, 06:13 PM
You don't say if you were using a tripod/beanbag or not - "not" introduces some variables which might at least mean you don't have to send your camera in for repair.

lichtloper
28th April 2010, 06:59 PM
Took the camera back to the shop today. The man in the shop immedeately affirmed that it has a viewfinder problem [possibly prism].

lichtloper

lichtloper
30th May 2010, 02:39 PM
Really miss the E-620.
It was my only camera - apart from my two analogue cams.
So after much hesitation I bought an LX3.

http://e-group.uk.net/forum/picture.php?albumid=92&pictureid=387

http://e-group.uk.net/forum/picture.php?albumid=92&pictureid=388

http://e-group.uk.net/forum/picture.php?albumid=92&pictureid=389

A pity that there seems to be no Oly P&S with ORF capabilities and with such a wide aperture lens as this little camera.

lichtloper

lichtloper
8th December 2010, 11:15 AM
Took the camera back to the shop today. The man in the shop immedeately affirmed that it has a viewfinder problem [possibly prism].

lichtloper

Sorry, haven't been posting for a considerable time; other commitments.
Anyway, got the E-620 back from Oly repair after four weeks orso.
But: the viewfinder still shows tilt, possibly to the same amount as before :(. Annoying.

When I want precise composition of my images I must use the LCD - which I don't like.
Looking at an LCD I cannot concentrate as much as I need/want.

Have sent them an e-mail to ask for advice.
Can they even get it right at all?

Btw E-620 has no "prism", but a configuration of mirrors.

[I]lichtloper

pepper
8th December 2010, 06:18 PM
I can't help you with your tilt problem, but you were also asking about the difference between exposure on using Live view and the viewfinder is because the light can get in through the viewfinder when using the LCD,

On the E3, when you go to use liveview, it tells you to close the shutter on the viewfinder, yet on my Panasonic L1 it doesn't tell you this, but does provide you with a plastic cover that slides over the viewfinder to help with the exposure.

lichtloper
8th December 2010, 07:32 PM
...about the difference between exposure on using Live view and the viewfinder...

You're right, of course, Pepper;
only later, after posting, I realized that the exposure difference indeed was due to the light getting into the camera through the 'open' viewfinder, thus influenceing the meter's reading.

Thanks, Pepper, and good luck, lichtloper

lichtloper
25th August 2011, 01:33 PM
Just received a 2nd hand 520 from eBay. It too shows viewfinder tilt:o, but to a far lesser degree than the that in my E-620.

After two failed 'repair'-attemps of the 620's viewfinder/prism I'm fed up with it and I'll settle for this 520... Though I don't know about image quality yet I think it handles better than the 620: I like the buttons on the left side of the LCD.

I must say that I'm mainly 'loyal' to Olympus for two reasons:
+ the three-by-four aspect, which I have come to appreciate over the 35mm's three-by-two;
+ and the 14-54mmII lens with its excellent image quality - unrivalled AFAIK by comparable lenses of Nikon or Canon.

[I]lichtloper

Ross the fiddler
25th August 2011, 10:19 PM
Just received a 2nd hand 520 from eBay. It too shows viewfinder tilt:o, but to a far lesser degree than the that in my E-620.

After two failed 'repair'-attemps of the 620's viewfinder/prism I'm fed up with it and I'll settle for this 520... Though I don't know about image quality yet I think it handles better than the 620: I like the buttons on the left side of the LCD.

I must say that I'm mainly 'loyal' to Olympus for two reasons:
+ the three-by-four aspect, which I have come to appreciate over the 35mm's three-by-two;
+ and the 14-54mmII lens with its excellent image quality - unrivalled AFAIK by comparable lenses of Nikon or Canon.

[I]lichtloper

It is a nice lens for a reasonable price. I got mine to go with my E520 initially & now it sits on the E30 for general use.

I hope you have success with your latest purchase.