eos 7d - rolling shutter - hard

X

xha1dude

Active member
Hey there, i got my 7d just today.
Shot a couple of images.
I realized there is a HARD rolling shutter on every movement.
ok i held the camera in my hand, but look here

http://www.oneshot-tv.de/rolling.mp4

i just laughed a bit at this shot, so its shaky, and there you can see the rolling shutter.

is this normal? or could my sensor be damaged or something like that?

can a faster CF card improve the problem?

lense was 50 mm ef 1.8
 
It's normal. Handheld with these cameras only works with practice and concentration. I was disappointed too when I got mine, but after shooting for a month I've gotten to the point where the footage is useable in handheld mode...

Also, a wider lens helps a LOT.
 
Your camera is operating exactly like every other one. You can't do shaky handheld shots like that with a rolling shutter camera, or you'll get the results you got.

So turn on the lens's stabilization, and get a handheld rig, and use a wider angle lens, etc... there are lots of ways to address it, but there's nothing wrong with your camera and no, a faster card wouldn't have any effect.
 
Are you using a IS lens it helps ssssoooooooooooooooo much... all I do is shoot handheld... until my shoulder rig is finished.
 
I did two 3 minute handheld interviews with the nifty fifty came out real good.
Tighten the strap around your neck ( dont kill yourself and ) and shoot .

You know a good thingto have like with any other camera is to purchase a stable tripod !
 
if the Red One is also a Cmos sensor how do those guys overcome the rolling shutter issue. or is the red not cmos
 
speedjunkie said:
if the Red One is also a Cmos sensor how do those guys overcome the rolling shutter issue. or is the red not cmos
Click to expand...
They don't overcome it. It has all the same issues. All the CMOS cameras do. Some are worse than others (like the HV20) but all the same issues remain.
 
speedjunkie said:
if the Red One is also a Cmos sensor how do those guys overcome the rolling shutter issue. or is the red not cmos
Click to expand...

When I first looked into the rolling shutter issue, I was surprised to learn that film cameras also experience rolling shutter. It is caused by the way in which the shutter literally "rolls" across the frame, capturing only a portion of any given image at any specific time.

Why then, I wondered, does it seem so terrible on some DSLRs, somewhat better on RED ONE, and essentially non-existent on film cameras? It turns out it comes down to the speed at which the shutter - electronic or physical - crosses the frame. In film cameras, this occurs very quickly...approximately 4µs. The RED ONE is at 9µs. The Canon 7D is slower than that, but I don't believe Canon has released an official spec.

So, RED hasn't completely killed the problem. They did improve upon it, however. In addition, it is less likely for someone to pick up a RED rig and try to shoot hand-held DSLR style with it. And even if they did, the increased weight would add some stability.

As for a fix, the closest there is should be RED EPIC, with an electronic shutter pass occurring in 5µs - 25% slower than film, but evidently very close.
 
To see how the Red handles erratic movements and whip pans, I suggest to take a look at the plane crash sequence in "Knowing" w. Nicolas Cage. (The entire movie was shot on Red.)

A solution to rolling shutter artefacts is to have a mechanical shutter in front of the sensor. That's what DSLRs do for stills mode anyways.

One camera that does that already is the Arri D-21: http://www.arridigital.com/technical/cameraspecs
 
Michael Olsen said:
When I first looked into the rolling shutter issue, I was surprised to learn that film cameras also experience rolling shutter.
Click to expand...
You should be surprised, because film cameras (movie film cameras) don't experience those issues.

You can get a little bit of flash-banding, but you don't get skew or wobble on a movie camera.

Those are artifacts that are unique to CMOS rolling-shutter cameras.

In addition, it is less likely for someone to pick up a RED rig and try to shoot hand-held DSLR style with it. And even if they did, the increased weight would add some stability.
Click to expand...
This is behind probably 99% of the difference between a Red One and a DSLR as far as wobbly rolling shutter, as evidenced in the OP's clip... the DSLR's are relatively "twitchy" and so they are far more likely to exhibit the issues. Red Ones aren't used frequently for offhand handheld stuff, they are usually fully built out with rigs and are very heavy and don't get tossed around like the SLR does. Build out the SLR with the same kind of handheld rig, and hang a 20-pound weight on it, and you'll find you can get the same kind of smooth handheld shots that the Red One shooter gets.
 
The foundry offers a rolling shutter plug in for After Effects and Nuke. I dont know how well it works but on the example video ..looked good also free for 30 days give it a try

:laugh:
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I AGREE
 
Barry_Green said:
This is behind probably 99% of the difference between a Red One and a DSLR as far as wobbly rolling shutter
Click to expand...


I disagree. THe main issues is the read-reset time of the sensor. The read-reset time on the R1 is significantly faster than any of the DSLRs at 24fps and that is because the R1 is a high speed CMOS sensor and the DSLRs are mostly 6-10 FPS sensors that use various tricks to achieve the speeds they do.

One thing you can do to see how read-reset time affects skew and wobble is to shoot 720p60 and 1080p30 on the 7D. The read-reset is almost exactly double in the 60fps mode versus the 30fps mode and so the skew and wobble is greatly reduced.
 
sblfilms said:
I disagree. THe main issues is the read-reset time of the sensor. The read-reset time on the R1 is significantly faster than any of the DSLRs at 24fps and that is because the R1 is a high speed CMOS sensor and the DSLRs are mostly 6-10 FPS sensors that use various tricks to achieve the speeds they do.

One thing you can do to see how read-reset time affects skew and wobble is to shoot 720p60 and 1080p30 on the 7D. The read-reset is almost exactly double in the 60fps mode versus the 30fps mode and so the skew and wobble is greatly reduced.
Click to expand...
I know all about the read-reset time issue, and I also owned a Red One. Yes it can be an issue (witness the skew performance of an HPX300 in 1080 vs. 720 mode) but the DSLRs that I have (GH1 and 7D) are prett much redlike in their wobble performance. I stand by what I said, which is that it's the light twitchiness that causes extreme wobble, and if you put a Red One with a 50mm lens in Lou Ferrigno's hands, you'd probably get comparable twitchy rolling shutter issues.
 
Hello everyone, read lots of things about this camera and the work around. MY question, Specifically if the 7D in 1080 / 24 p kit lens is locked down with a material stronger then steel, no zooms pans or tilts, filmed in wide mode will there be cinematic glitches that a pro will see on the Big screen with no down conversion?
 
You're really asking about several issues at once and it depends.

Rolling shutter: No, you won't see rolling shutter issues if you pan slowly, or not at all, and aren't following fast motion. Not really different than any other CMOS camera in that regard.

Moire: You won't see moire unless there is a repeating background of specific frequencies.

Aliasing: You won't see aliasing on organic shapes.

The strengths of the camera are its low light, dof control and manual controls at 24p. Plan to avoid geometric shapes and fast movements.

If you look around you'll see the short Philip Bloom shot at the Skywalker Ranch and played for George Lucas, Quintin Tarentino, et al on a 40' screen. They liked it.
 
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