Imported 7D Videos Suffer from Random Pixellated Distortion--Help!

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New Member
Jun 3, 2014
Lightroom Experience
Lightroom Version
Hi community,
I'm a newcomer to the forums, and I come with a most unusual issue. I am using a Canon EOS 7D to shoot stills and video. Recently in Lightroom, my .MOV files have a distortion/pixellation issue that sporadically occurs throughout playback after importing into a catalog. The video size and FPS doesn't seem to matter (i.e it happens at 1080 24fps or 1280 60fps). It looks almost like a film problem from back in the day. Additionally, my .CR2 files are copied and converted into .DNG files in the catalog, and they sometimes contain this weird purplish-pink distortion that overlays the image. (This is probably an independent issue that I've thrown in here).

I've searched Google, I've searched the Adobe forums, and I don't know how to get in contact with someone who may know what this issue is that I'm experiencing. I can't seem to find any mention of this issue. At first I thought it was my camera, but I checked the .mov files before importing into Lightroom, and they're not experiencing this glitch. I also tested multiple CF cards and ruled them out as the cause (using Sandisk 160Mb/s). The main question/concern I have is what is Lightroom doing to these .MOV files upon importing into a catalog? I can upload examples to a location if you need to see something, for it seems that this is something only I am experiencing. I really hope it's not my computer, check out the specs below...

Computer and Software Specs:
-Lightroom 5.4
-Apple iMac 10.8.5 with 3.4Ghz Intel Core i7
-16GB 1333 MHz DDR3
-AMD Radeon HD 6970M 2048 MB

Thanks so much for your help and guidance! Please let me know if something is not clearly explained or I failed to mention an important detail.



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Those look like corrupt files, or less likely, bad RAM. I would back everything up right away, then run system diagnostics.

Another possibility, surprisingly common, is that the files were corrupted in the process of copying them from the card. Are you copying straight from the camera or using a card reader? Try swapping card reader, cables, ...
Thank you for those suggestions. I am using a card reader but never considered that to be the source of the problem. Could it be that I'm using a USB 3.0 card reader in a 2.0 port on the computer? I've only recently come across this issue. Unfortunately, I don't have any extra readers lying around, but I will try a direct link between camera and computer and see if there's still an issue. However, if it does turn out to be the card reader, do you know what exactly that means--I find it odd that it could be broken? And could it be fixed? Is Lightroom not at fault here? I guess I will test this out and see; will report my findings here asap.

Also---I'm not sure what System Diagnostics refers to on a Mac.
I don't think the 3.0 reader in a 2.0 port is likely to be the problem, but things like bad readers and bad cables have been known to cause similar problems in the past. I think it's unlikely Lightroom is at fault.

Here's Apple's page on running diagnostics: (I'm guessing your system is new enough for that one. Pay attention to the first bullet, just in case.)
Thanks Mark, you identified the issue spot on! After uploading the same footage via USB directly from the camera, I no longer had the distortion. I swapped out the cable for the card reader to determine which part was having the issue, and it turns out to be the card reader. Hmmm, I never would have thought and I have no clue why! Thank you again Mark, I feel bad for blaming Lightroom now. I love this program so much, and I hope it forgives me hehe :p
I always recommend that people buy a high quality card reader. A Lexar Professional card reader can be had for less than 30€. Buying a cheap card reader is simply asking for trouble in my opinion. Buy a name brand, high quality one and you may never have to buy another.
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