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View Full Version : Strange Dropped Frames Issue



Tanner Stauss
01-08-2009, 06:42 AM
Today I had a strange thing happen.

-We were shooting a small pistol inside an average sized office;
-We were shooting on CF cards, at 113fps
-and we still got dropped frames.

It happened in an usual way though. There were two shots being fired from the gun, the gun was pointed straight at the camera and it was about 12 feet from the lens.

The dropped frames did not occur over the loud points, or after, as they did before when we got dropped frames on the RED Drive, but they were before the gun was even fired. For about 1-2 sec of gunfire, we got 120 dropped frames, and then 129 dropped on two separate takes. And, like I said, the dropped frames only showed up in the footage before the gun was fired, technically, the moment we wanted was fine and looked good. But this was still strange.

We canned the card, switched it out, power cycled the camera, and then shot a squib that was much louder than the gun by far...no dropped frames.

Vigen Vartanov
01-08-2009, 07:09 AM
On CF card i thing that it can be CF Module . Try to check it without guns , just put camera on Record and record 10 cards , if result will give you droped frames , its looks like bad CF module .

Shawn Booth
01-08-2009, 04:04 PM
There are shock waves with ALL "explosives" but you're saying it occurred B4...

When B4? Seconds B4 the gunshot? Milliseconds? If latter is the case, it seems as though the gunshot concussion is causing your dropped frames. If it's occurring a second or longer B4.... no idea.

Tanner Stauss
01-09-2009, 06:08 AM
The dropped frames would start about 2-3 seconds before the gun shot. In playback it would stutter and spit until 1 sec or less before the gun shot, then it would play fine through the rest of the take.

Colin Hubick
01-09-2009, 01:10 PM
Is the pre-record function enabled? If it is, it may have something to do with the problem, and would possible account for the problem prior to the gun shot going off...

just a guess.

Tanner Stauss
01-10-2009, 06:19 AM
Is the pre-record function enabled? If it is, it may have something to do with the problem, and would possible account for the problem prior to the gun shot going off...

just a guess.

no pre-record.

but I did find something yesterday. I opened up the CF module to check it out and the e-sata cable was about 1mm or so loose. I snugged it back up, then did some tests with and without gunshots, also with and without highspeed...no dropped frames. This may have been the problem.

I had to fix the same problem when I first got the camera delivered. I was testing it out of the box, and CF cards were not mounting at all. Opened up the CF module, snugged up the e-sata cable, problem solved.

...which means that within about one month, the e-sata cable came slightly loose from use.

I'm not sure, I'm just going to call "Murphy's Law" on this one.