Re: Canon Powershot G7 "Unidentified image"

On Nov 25, 10:17 pm, Dave Cohen <u...@xxxxxxxxxxx> wrote:
anira...@xxxxxxxxx wrote:
On Nov 25, 3:08 pm, Eric Stevens <eric.stev...@xxxxxxxxx> wrote:
On Tue, 25 Nov 2008 01:10:51 -0800 (PST), Bengt T

<bengt_tornqv...@xxxxxxxxxxx> wrote:
On 25 Nov, 09:45, Eric Stevens <eric.stev...@xxxxxxxxx> wrote:
On Mon, 24 Nov 2008 19:36:14 -0800 (PST), anira...@xxxxxxxxx wrote:
Funny that it also happened to my G7 just a few days ago. After over
4000 shots and never missed one. Then, suddenly this "unidentified
image" message came up when viewing the photos. Sometimes, the shot
came up (small size), but then disappear. Sometimes, instead of
"unidentified image", it comes with a "question mark" symbol.
I also noticed that my SD card is being "depleted" slowly. After
cycles of cut and paste into the computer, the number of left over
photos to shoot decreasing.
Try reformatting the card _in_the_camera_  _with_the_camera_
But this is perhaps a different problem.
Going back to the "unidentified image", I found the images are still
available ( 3 MB per photo), but I could not open in any photo viewer
software, I am trying to get specialist to try to open the file (if it
si possible).
About the unidentified image, I replace my G7 with a completely NEW SD
card, and so far it looks OK (but have not tried it many times, just a
few). I am assuming that the SD card that is broken, not the camera
(Crossing my finger :)). Try if you can get a brand new SD card and if
it is working.
I hope mine is solved, although I am still not 100% until I started to
use it again. Next time I may need to bring 2 cameras, just in case
the G7 is busted.
Yes, I also noticed when I view some of the saved pictures, there are
block of the photo areas which are mixed up with other shots. So,
Perhaps the formatting of the photo is not complete, or mixed between
photos ----> don't know if this is the camera;s fault... or the SD
card. I hope it is the card and nothing to do with the camera. Perhaps
contacts with the SD terminals (worn out after SD card is inserted in
and out many times. Unfortunately, I never download photos using a
cable connection. It is just too cumbersome. It is faster just to pull
out the card and insert into my computer. Perhaps this may be the root
of the problem. Connections or contact are getting loose?
I like to hear from others who experience the same problem.
I wonder whether it is time to trade in with the new G10. They will
pay me for $200 for a new G10 and pay the difference (another $250)..
Mine was over 1 year old and so far, never have any problems.
On a different topic, I saw some photos taken in Lumix LX3 and they
are just perfect. I saw that the quality of the photo is better than
Canon DSLR 50D! ( Quality comparison - LX3 , Lumix G1 and Canon 50D -
in that order) I also saw someone taking panoramic photo at night and
it is spectacular, sharps and no grains. Should I start thinking of
Lumix LX3? DPreview just came out with their review of LX3. It has
9/10 for optics. Perhaps it is in the lens!. But I was surprised on
how excellent the photos taken by LX3. I wonder if others experience
the same thing with their new LX3.
Bengt T wrote:
With C1 program setting I have programed the camera to take 3 pictures
(normal, under- and overexposure). Sometimes, mostly from picture no
257 in the used SD card, I get the information "Unidentified image"
when trying to look at pictures on the display of the camera. Viewing
the pictures on a PC some areas are distorted or with areas blank.
It seems to me as the camera has problems in writing information to
the SD card in certain memory areas. I have tried reformating,
different SD card manufacturers etc. with the same result.
Does anyone else experience the same problem?
Eric Stevens
I have tried reformating. The problem remains.
OK. You can cross that one off then.

Eric Stevens

Just another note about my G7. After I install a new SD card, it does
not seem to have any problem. I tried 4-5 shots and they are all OK.
So, I actually never know what happened, except that it is likely due
to the SD card.
One of my friend indicated that because I used the cheap card from
Walmart ( not a good brand name), it is slow process. Therefore, when
I shot the camera consequtively ( within tens second each), I found
out that only the last one registered. The preceeding photos did not
make it, although the file with JPG name is already created.

Anyone knows how to extract a JPG file that is not recognized by major
photo viewer softwares? I tried photoshop, paintshop, MS photo viewer,
and others (Corel draw, adobe illustrator). But they did not
recognized it. Any other suggestion? A software that can open a
'corrupt" JPG photos?

I still did not get it that when the SD card is used many times and
deleted, the number of available photo from the empty card seems to
decrease with time. Just like when you are using MS windows software,
that there is some file that I don;t know are being filled in with
basic data, which accumulated with time. They never tell us on how to
clean sweep the software. In the past such windows software appears to
slow down the system, by taking the internal RAM or memory bit by bit.
I wonder if this is also the case when you fill and withdraw the photo
files in an SD card. With time, the card will be full, although it is
always emptied all the time. I even wonder if deleting using in-camera
feature is better than using your computer.I also wonder if
reformating the card will clean the data and empty all unnecessary or
"residual" files in the card.

Another related question is whether deleting files in an SC card just
merely take the JPG extension so it cannot be read. Then the data file
will only be erased when new photo images is taken and replace the old
one. Just similar to how the hard drive of a computer is working. To
erase and clean, you need a special software or reformat?

Thanks for the discussion.

Files are not physically deleted on any media. The space the file
occupies is marked as free in the fat table and is available to be
overwritten. Photo recovery software is able to retrieve files so marked
if they haven't been overwritten.
Dave Cohen

Any particular photo software that can retrive corrupted JPG files?
Any of the freeware?
I checked by googling "unidentified image for Canon ", and I am very
surprised (or shocked) that there have been dozens of others who
experienced similar problem. I start to have uneasy feeling about my
camera. It is working OK now with the new SD card. However, I start
have a sinking feeling that this is not just merely an SD card
problem. The problem appears to be wide spread among the A series, and
perhaps the G and S series.... practically all of the P&S camera?
Unfortunately, I don't seem to hear any constructive solutions.... all
questions and no solid answers.
I had so much confident before that my camera would always deliver. I
had over 4000 photos and it never failed..... until just a few days
ago. Now, I wonder whether I should bring a second camera around, or a
spare SD card..... uncomfortable feeling!. My cheap basic Lumix P&S
(only 3 MP) is over 6 years old and with 10,000+ shots... and it is
still working!

.