Hi all,
As you all know, we are capable of getting a great look using "frame mode"; however sometimes I forget to switch back to normal when panning something (and we all know what that looks like). My question is: does anyone have any suggestions on how to salvage this footage in post. I have Vegas 4 (very happy with it, so please don't try to convert me) and tried "super sampling" but it didn't seem to help. Vegas also automatically describes the clip as "progressive scan" under properties (as opposed to "lower field first" as it does with clips shot in "normal mode". Any thoughts?
TIA,
Randy

I can't help you out because I've not really had this problem.
The higher shutter speed you'll use the less it stutters when
it pans. I always shoot in frame mode also when panning. I
shoot in PAL with a shutter of 1/50th. At what setting are you
shooting?

Thanks Rob,
I usually shoot between 1/30 to 1/60
Thanks again,
Randy

Maybe we DON'T all know what I'm talking about so please allow me to elaborate: When I pan in frame mode (with either of my XL1S') or there is fast movement in the shot, I get unusable "blocky" footage. Shutter speed doesn't seem to make a difference.
Can someone please just tell me what you do (when using frame mode) when panning, do you have to switch back to normal mode, do you treat it differently in post or what?
Thanks,
Randy

Hi Randy....

The problem you're facing is what some people refer to as "stuttering" where pans look jittery.

I don't know what the formula was, but with frame mode (or productions shot on film) certain pan speeds are avoided. They'll go either faster or slower, but certain pan speeds look really bad.

I've seen this happen in major Hollywood productions. It's an effect of shooting at a slower frame rate -- with interlaced you're getting 50 fields per second or 50 half-resolution frames per second. With frame mode you're getting 25 frames per second. So movements such as pans and tilts aren't depicted as smoothly.

Not a whole lot you can do in production or post-production except avoid panning at certain speeds.

Dean Sensui
Base Two Productions

Well, he said that changing the shutter speed didn't help.

Can you post 1 frame where this "blockyness" happens? Or if
you don't have a website e-mail me one picture please directly
from the movie.

As I said before, I just shoot pans in frame mode. Don't do
nothing with them before, while shooting or in post.

There are detailed charts that spell out what panning rate you should use, to avoid stuttering with a film camera, based on the focal length of the lens and the FPS you're shooting at. You can find them in the American Cinematographer's Manual.

However, it can also be summed up with this rule of thumb: an object should take about 7 seconds to cross the screen. Any faster than that and there will be noticeable stuttering.

With an NTSC XL1 in frame mode, the faster 30fps capture rate would mean that you could pan a little quicker, so perhaps six seconds for an object to cross the screen...

Stuttering pans belong to the world of "film look". Some people aparently like thes artifacts... If the motion is slow enough the eye has learned to live with those shortcommings and film people have learned how to "hide" them. If you want to limit those temporal sampling effects and artifacts (like the reverse rotating stagecoach wheels) its important to use the longest possible shuttersetting (1/50 or 1/60).

Wow thanks everybody!
I've never seen this kind of response here. Anyway, Rob I e-mailed you a .jpg of the blockiness I was referring to....if anyone else is interested let me know (sorry, I have a website and I even uploaded the .jpg, but can't figure out how to link it where you guys can see it....maybe after I wake up)
Thanks again everyone,
Randy

I looked at your picture. I'm not sure why you are calling it
blockyness because I don't see any. Your probably talking about
the blurry stuff that is going on? The lower the shutter speed
the more blurry it will get. The easiest resolution is to increase
shutter speed.

If I'm interpreting it wrong it might be time to put up a short
movie sample for everyone to see.

I'm basically out of suggestions for you...

Sorry, maybe I'm not clear on the terms, perhaps blocky means pixelated? Maybe stuttering is the term I should have used (or maybe just crappy); anyway, I apologize for my ignorance but perhaps I'll try to shoot some test footage at a higher speed; I just didn't think that could be the answer since the image in the viewfinder gets worse.
Thanks for everyones patience,
Randy

Try turning off the image stabilization. I have had some luck with this approach; after all you are trying to use motion, while the cam is trying to cancel motion. Sometimes leaving this on with the cam locked down may cause the IS system to try and remove in-frame motion.

Just a thought ;)

Turning off EIS will partly solve the stutter visibility because of the shutter speed lowering. OIS will not change stutter behaviour when panning

Hmmm, makes sense Joe, I'll try it. Andre, what's the difference in OIS and EIS (while you're at it what does EIEI O mean : )
Thanks guys,
Randy

EIS is "Electronic Image stabilisation" wereby the image readout zone on the CCD is permanently adapted to the (shaking) image it gets. In order to get rid of motion blurr (because the image still moves on the CCD) the shutter speed is automatically set somewhat higher (1/100). Higher shutter speed makes stuttering more visible. OIS is "Optical Image Stabilisation" . Here the shaking image is made stable on the CCD using optical elements which adaptively bend the incomming images so that there is no longer motion on the CCD level, and no need for shorter shutter settings and thus no effect when being set "off"

Thanks Andre;
>>the shutter speed is automatically set somewhat higher (1/100). Higher shutter speed makes stuttering more visible<<

So if I understand that statement, you feel turning off the EIS on the XL1S can actually make stuttering worse.
Thanks again,
Randy

No Randy, a small amount of motion blur is what you need for lowering the stutter visibility. EIS lowers blur and is best to be switched off. XL1 has optical stabilisation (OIS) I think, so it does't matter.

Sorry it took so long to get back to you Andre; so I guess I have 2 options:
1) don't pan (or do so very slowly)
2) switch to normal mode

Oh well, my thanks to everyone for your time, effort and patience.

Randy

Can we get a clarification on the Canon being OIS or EIS? I ask because it actually states in the manual (or on the website somewhere) to remember to turn OFF the IS when panning because it will cause stuttering. That's straight from CANON. I'll try to find the info to backup my statement, but I'm pretty confident I didn't dream this up.

I think shutter speed variations can help your situation, I'd consider switching to NORMAL a last resort.

Nevermind, it's definately Optical, but it does say to "Keep the image stabilizer turned off when the camera is mounted on a tripod." (page 40 of the XL1s manual)

I'm new to film, but not to digital signal processing. The panning rates depend on the resolution of the features of the subject and
the frame rate. Video is a three dimensional signal stream, with two dimensions in a frame and another dimension in time. To avoid aliasing in digital signals, the highest frequency must be 1/2 the sampling frequency. So, panning rates would be optimally determined by these rules of information processing.
However, optimal panning rates that don't alias (stutter, "shear", etc.) will probably err on the slow side.

Pan tables exist as guidelines, but it's pretty clear that
subjects that occupy a large % of the frame area with gradual feature changes will allow for faster pans while subjects with sharp feature changes that approach the video pixel size will need slower pans. Just try panning on a school yard fence/chicken wire. Slower shutter speeds will enable a general blur the motion over the frame, yielding smoother pans due to the averaging of information within a frame.

Let me see if I can restate this:

The amount of aliasing is proportional to amount of movement (independent from the pan motion), where the aliasing increases as the independant motion decreases. And the size of the object in motion is also proportionate to the aliasing in that the aliasing decreases as the size of the object in motion increases.

Is that right?

Hmmm, so in other words, if you can't plan/rehearse your shot, either don't pan quickly or use normal mode : )
I do a weekly local TV show for a producer that loves the film look I can obtain with the XL1s; after my last post, when I explained to her that frame mode has the same attributes (drawbacks) as film she was understanding and so everything is cool.
Thanks for the replys guys,
Randy

Alex,

Yes, aliasing is proportional to the amount of movement / data rate. This "movement" is actually high frequency information. Sharp edges are constructed with higher frequencies, so fine features such as wires will need slower panning/zoom rates.

Aliasing, if it occurs at all, decreases as the information bandwidth decreases. Objects with softer edges will alias less and allow faster panning/zoom rates.

G. Randy Brown,

Yes, we are guilty of trying to understand the limits of panning and zooming. I believe it is possible for a camera to
offer warnings on panning and zooming, especially when HD cameras will be used to produce SD video. Using zebra bars or something, the display where the aliasing will occur. This would be yet another tool to help rehearse camera moves.

Thanks Gints.
Randy