cf card question

[Vicki]

I've noticed when downloading photos from a card reader to my pc, that sometimes photos will be on the photo card out of numerical order. (I view the time of day the photo was taken)

what causes this, and can I avoid it? I've got two different brand cf cards, plus I've borrowed a different one.

Or is this a camer problem? I shoot with a Canon 20D

[Rufford]

First and more importantly, welcome to Byte!

As far as your memory card concerns, I have the same issue every now and then on my digital rebel. I have yet to figure out what it is, but at worst it's just inconvenient. I noticed, however, that the issue is much rarer if you download the photos through the canon software. For me, the faster uploads with a card reader far offsets the occasional photo flip-flop.

[Vicki]

thanks! I didn't even install the Canon software, I just use the Windows window that pops up, then download to an external harddrive.

I have yet to learn how to use my Adobe Photo Suite, so I really haven't worked with my photos much. My sons high school posts my photos and parents enjoy them. So that is the extent of my photography career.

[bytethis]

Hi Vicki and welcome.

Happens to me also, and I suspect that it's the CPU of the camera, (or perhaps just the buffer) telling the camera to write the smaller of the files (maybe taken in a burst of several) to the card first to 'get them out of the way' quicker so that the buffer can be freed up earlier.

That may be an out of sequence thing, if say, most of your pics might be 5mb for example, but a sudden darker image may contain less visual data and be 4.83mb so therefore that might be released onto the card quicker than the larger ones which would take longer to write to the card.

Does that make sense?