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Mark 4 Changing Card Format in the middle of a shoot!


Mark 4, 21 months old (refurbished from Canon) used for weddings, portraits, sports.  I always assign the CF card to RAW and the Sandisk Extreme card to JPEG large.  While downloading about 1900 images from the compact card the format jumped to RAW for the remainder of the wedding.  I changed batteries turning off the power before opening the battery door, which is my normal practice, sometimes forgetting but not yesterday.  There was no way for me to know during the shoot, i didnt use the wifi for downloading a lot of photos, maybe 2 or 3 JPEGS from early in the shoot.  I checked the cardreader and the card separately and put the card back in the camera today to see what the format would default to.  It read exactly like the PC, JPEGS to raw in the same order. the CF card was fine, all RAW.  Luckily i didnt lose any files, just more work to process images.  I have only read this happening a couple times in this forum, i will google it to determine the frequency.  Also i will shoot more with the cards to see what happens.  Now Canon will say its the card, or the formatting.  I dont buy that, it was fully formatted in the camera, and i didnt change the preference so it has to be the camera, which is scary...


Multiple shoots this month make repairs impossible.  I dont want to rely on my backup 6D and 50D but i may have to.   Canon, i believe this happens more than they know; you know for every complaint, theres 9 people who experience the same thing and dont report it to Canon.  When repairs are finally estimated i dont want to hear what i heard for the 600 RT flash i submitted for repair; " Parts are no longer available for this model but we offer refurbished at a discounted rate.  We do not have any refurbished inventory." 


Has anyone experienced this, with any camera model using compact and CF cards.  I will post my test results. 



Whenever you remove a memory card, the camera settings may change, because there is a missing card, which can no longer be written to.  Always recheck your settings when you remove and re-insert memory cards.


I do not experience this issue.  I typically use one of the custom shooting modes in all of my bodies, with updates disabled.  Switch the camera out of a custom shooting mode before you remove a memory card.

"The right mouse button is your friend."

i dont think thats correct because opening the card door turns the camera off.  Possibility of a change happening when its off is pretty sllim unless this has happeed to you.  anyway that was not the situation.  Cards are not touched until shooting is completed.


"Has anyone experienced this, with any camera model using compact and CF cards."



Personal opinion is, never put 1900 images on a single SD/CF card. Way too much chance of something going wrong.

If you think you need a minimum amount of SD/CF cards at least use one for the pre-wedding, one for the wedding, one for the wedding party photos and one for the reception. Four CF cards!


BTW. always shoot Raw! You bought the best camera you could get so why settle for lesser than the best photos from it?

EOS 1DX and 1D Mk IV and several lenses!

thank both of you, but you didnt read the post carefully.  the change happened right in the middle of a shoot, no cards removed, shooting from one photo to the next.

Your premise of using 4 cards is not practical.  Thats why you invest in a good camera.  Imagine shooting a fast moving sporting event and trying to change cards when they are not even 1/4 full.  Thats why there are dual card slots.  I always shoot raw, but dont have to use them unless there is some major correction to do on an image.  I dont know of anyone shooting 4 cards for a wedding or any other high capacity event unless the cards are full. 


You dont buy a $3000 camera and then compensate for formats changing in the midde of a shoot...

Awaiting an answer from Canon...

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