huge jpeg files show as very small thumbnails (canon 300d, JPEG)

I've got these 3 Mb JPEG's from a canon 300d but when I open them up in any
decent viewer (irfanview, et.al.) they show as very small 50Kb 160x120
thumbnails. How can I get to the large versions (they must be there, the
files are huge)!?

Any help appreciated.

 

How are you viewing those files? What OS and viewing software
are you using?

 

Did you set the camera to RAW mode before taking those shots? If a file has
the extension CRW, open it using the Canon File Viewer Utility that came
with your 300D. Go to File, Save File, Convert and save in file and you
should have three conversion options.

 

Thanks Jim, I was a bit 'beyond' this, but thanks for telling us - it might
help someone. I'll be a bit more explanatory on the background next time.

The issue at hand is that these large files seem to be some kind of
proprietary jpeg-based format. It looks as if they have some multiplicy
built in that no normal jpeg reader understands (JPEG is, by nature, not
multipaged, as for example GIF is). Does anyone perhaps know which exotic
vendor-specific flavour I could be dealing with here? It's not PCD
(photoCD), an none of the usual range of tools (photoshop, irfanview,
imagemagick, etc.) recognizes it as anything else.

Thanks!

PS these are photos directly from a Canon EOS 300D memory card.

 

Odd. Canon usually store their JPEG files in some flavour of Exif.

And you are absolutely certain that these files are valid?
Does the Canon supplied software read them OK?

I'd be interested to take a look at an example file.

Regards,
Martin Brown

It can be either. Most digicams hide a thumbnail in the header that the
viewing software may or may not utilise. Seeing a good thumbnail is no
guarantee that the file is valid. Opening the file is the acid test.

A quick test to see if there is something like a valid JPEG (or
compressed TIFF) file is to try compressing it with ZIP. If it can be
compressed by more than about 5% then it is very probably damaged.

Regards,