"Mike Russell" <groupsRE at (no spam) MOVEcurvemeister.com> wrote in message
news:1gqu6r7l1z3r5$.dlg at (no spam) mike.curvemeister.com...
On Wed, 4 Nov 2009 12:34:20 +1000, Here's Johnny wrote:
Hi all,
I am not a photographer (though very interested in photography!)
but I do fairly basic digital retouching for wedding customers. I
have received a few
discs of photos from the same photographer a few times now with the
same problem.
About a quarter from the left border of a landscape image, a
vertical, single-pixel greenish line run through. I've zoomed in
and can see a small
(maybe 2x2 pixel) white spot about 5 pixels from the top of the
image, and
the green line runs vertically down from there, right to the bottom
of the
image. This littel white spot looks like there's a "hole" in the
image, which is "leaking" the green line.
Can this learned forum please advise me as to why this keeps
happening? I have raised this previously with the photographer and he
told me
last time
it was down to a corrupted media card. That sounded wrong to me, as
an IT support pro - if the media card was corrupt, we would be
having other issues. (That's not to say he was being dishonest -
he's not an IT person.)
He told me he ditched the faulty card, but here we are again. I
suspect he's
mis-diagnosing the problem, and that ditching this data card too
will not fix the issue.
Could his explanation be right? I suspect it's a problem with his
camera and
that he's giving me excuses to fob off having to spend money on it.
I'd be
very grateful for advice, as I don't want to dismiss him if I'm
wrong. He tells me he took many more photos after the ones he took
for me, and none of
them have this issue, so he reckons it's ot the camera. Then again
he never
noticed this the first time, nor this time, until I raised it with
him.
This is definitely a problem with the camera. The manufacturer may
replace
or repair the camera free of charge. Nikon, for example, will
replace defective coolpix sensors, even for out of warranty cameras.
Meantime, it sounds like you have a bunch of images that you need to
fix, and it can get boring, and costly in terms of your time, using
the clone tool that many times.
There are several ways to go. One effective procedure for this
would be the dust and scratches filter. Set the pixel radius to 1,
and the threshold at 55 or so. Zoom to 100%. While in Dust and
Scratches, toggle the preview check box to make sure that you not
see *any* change in the rest of the image. If you do, adjust the
threshold higher. Watch for changes in fine contrasty detail such
as hair against a dark or light background, jewelry, eyelashes, etc.
You should see nothing change. Check
several different images to make sure that no detail is lost.
In the unlikely event that you do see degradation, do a one column
selection of the vertical green line, plus the cluster of green
pixels you mentioned. Turn off aliasing and set feathering to zero.
Record the procedure as an action, and apply it in batch mode to the
set of
images.
Dust and scratches is very effective in this situation because it
reconstructs pixel data from adjacent pixels, in effect removing the
green line by averaging pixel data from adjacent pixels.
--
Mike Russell -
http://www.curvemeister.com
weirdly coincidental and probably off topic- was watching a TV show on
lasers
the green laser bounced off some dust particles and damaged the photo
crew's camera- similar result- damaged the sensor card (was there a
laser light show at the event?)
I have seen image from not fully charged batteries or damaged card,
not fully uploaded images but it looks more like static or half an
image with the rest static noise
if the flaw is same place every shot usually indicates in camera
problem
