View Full Version : Filming Dancers


Eric A Robinson
May 16th, 2005, 01:37 PM
Hi All

I have recently been filming dancers in low to medium light conditions making use of natural light or any stage lighting that has been available and the XL2's have done very well (PAL user).
My question is:-

What would be the best settings for this type of situation? Previously I have been using 25P/ 1/25th.

I would like to capture the motion of the dancers with a minimum of blur, which I have noticed during sections with fast motion.

I have been filming a series of interviews with visual artist using the above settings, making use of what light was available, and the cameras again have produced some excellent results. My aim being to cause minimum disruption to the environment in which I am filming.

Am I right in thinking that using the miniDV format frees the user form the constraints imposed by other formats, in particular that of the requirment for additional lighting ?....

For me, one who works as a solo operator, this has been a huge advantage when trying to capture those intimate moments, when the subject s not being put off by large amounts of hardware being pointed at them.

Any comments would be gratefuly received. Being relatively new to this, I only got my XL2's in December.

Jimmy McKenzie
May 16th, 2005, 02:41 PM
The stage performances that I record are set for performance and not video lighting. Ignore the black. Ignore the viewfinder under-exposure meter. As long as the performing arts theatre is using a full wash of stage lights to light the faces, you can ignore the rest. Wide open iris.0 gain. 60i. In your case 50i.
Unless the ballet portion is very dark or if the irish costumes are dark on a dark backdrop you should be fine.
I use 2 xlis simultaneously behind the glass and feed line in from the mixer to both so the 2 cam edit is simple. Cam 1 is the safety cam. Cam 2 roams about panning and zooming (slowly) for 2nd angle shots. If you are going to exceed 1 hour, be sure to stagger start the cams so one is rolling during tape change.
The hardest part is anticipating the moves in jazz and lyrical performances. Wider framing is the key on the second cam. Once you have that sense of the art, the rest is easy.

Richard Hunter
May 16th, 2005, 06:45 PM
Hi Eric. Unless you particularly want the motion blur effect, 1/25s is just too slow for shooting with. This default setting for 25p XL2s is just wrong. You should try it at 1/50s which gives very nice results. (For your reference, the equivalent NTSC cam 24p mode has a default shutter speed of 1/48s).

Richard

By the way, how's Edinburgh nowadays? I used to live there before moving to Singapore in 1991.

Eric A Robinson
May 17th, 2005, 01:32 PM
Hi Richard

Thanks for the advice, its what logic told me would be the case, but it is always nice tohave it confirmed by others. I know this has been asked before ... but why did Cannon make 25P at a 1/25 the default?

Would you use the 25p at a 1/50th for most applications? Will it produce a 'sharper edged look' as a result of the higher frame rate?

Will I have to be aware of any knock on factors?

Edinburgh has changed a lot since the early 90's, mostly for the best. It is now a truly cosmopolitan place with people from all parts of the world. This diverse influx has helped to produce a melting pot of new ideas, and for may creative minded people it is quite an exciting time.

David Lach
May 17th, 2005, 02:25 PM
Eric, the more you increase shutter speed (bigger fraction values), the sharper (but also the jerkier) it'll get. So the faster the action, the faster the shutter speed (if you want to avoid motion blur).

Now, it beats me why Canon chose 1/24th and 1/25th as default values for the 24p and 25p options on the XL2. I don't care that much since I pretty much always use it in manual mode, but it looks like a brain cramp, unless someone can chip in with a different explanation.

typical values for 24p, 25p/50i and 30p/60i are respectively 1/48th, 1/50th and 1/60th. I'd say you're good to go with those 80% of the time (typical shooting situation). You might want to increase that number however when the action gets faster paced. And you can decrease when the motion blur is a wanted effect or when there is very minimal motion and you're underexposed (you'll get more light in at 1/25th than 1/50th).

Also, remember that frame rate and shutter speed are 2 different variables. The frame rate is the amount of pictures the camera samples every second, the shutter speed is the amount of time each of these pictures is exposed to light (the shorter it is exposed, the less likely it is to have motion blur).

Richard Hunter
May 17th, 2005, 07:07 PM
David, from what I have read I believe the default shutter speed is 1/48s for 24p (but I don't have the NTSC version XL2 so please correct me if I am wrong). That is why it is hard to see the default 1/25s in 25p as anything but a mistake.

Eric, I usually try to use 1/50s when in 25p mode, but if I want to force the shot to have a narrower depth of field, sometimes I will go for a faster shutter in order to be able to open the lens up. As David mentioned, the frame rate is not changed by shutter speed. Using a faster shutter speed in 25p will produce a kind of strobing effect on certain movements (either subject moving or camera moving). Sometimes this will be OK, but other times you might prefer to use a slower shutter and get more motion blur.

I'm planning to visit Scotland for a holiday in late July. I doubt if I will be able to take my XL2 on the plane, so most likely I'll bring along my old VX2000 instead.

Richard

David Lach
May 17th, 2005, 10:05 PM
David, from what I have read I believe the default shutter speed is 1/48s for 24p (but I don't have the NTSC version XL2 so please correct me if I am wrong). That is why it is hard to see the default 1/25s in 25p as anything but a mistake.

Unless Canon fixed it in later models, mine shows that it still does the same thing with the NTSC version. The XL2 by default will automatically choose 1/24th in 24p and 1/30th in 30p. Lots of new owners came in here asking about that thinking the proper shutter was therefore 1/24th, 1/25th or 1/30th, which is plain wrong, and leads to unwanted blur effects in most cases. I must say even though this has absolutely no consequences on the way I shoot, I would really like to get an answer from Canon as to why they did this.

Eric A Robinson
May 19th, 2005, 06:00 AM
Hi again

I am still worderiing about the underlying mechanisms of 25p at 1/25 or a 1/50.

If you fill at a frame rate of 25p per second and a shutter speed of 1/25 then the image captured is in sync with the open shutter....., though you will get some blurring during fast action.

If you film at a frame rate of 25p per second and a shutter speed of 1/50 then the shutter will open twice during the time the frame is being captured. Is it the case then the image captured will be from the second opening of the shutter? If this is the case then 1/50 of a second of action will be lost between each frame, but I suppose due to 'persistance of vision' it does not matter. I suppose also this is why during fast action, blurring will be reduced.

What will be the effect of filming at 25p with a very high shutter speed? when would it be useful to do this?

David Lach
May 19th, 2005, 06:52 AM
Eric, if each frame lasts 1/25th of a second and the shutter opens for 1/50th of a second for each frame, you will indeed lose half of the "reality" as it happens before you for each frame.

There is nothing new to this process. Film works at 1/48th shutter for a 24fps rate because it needs half the time to expose and half the time to move the film in the camera while the shutter is closed.

The higher the shutter speed the more "picture burst" like it becomes, meaning there's more and more time that separates each exposed moment of reality (hope that's clear enough, somehow I think not so much). In other words, the sampling is still done at 24fps, but it only exposes the action in each frame for half the time.

This is only noticeable when the action is very fast though, because in normal shooting situations, 24 images per second at 1/48th shutter is quite enough to recreate the illusion of movement. But obviously, as the action gets quicker, you either accept a rise in motion blur or increase the shutter speed to get sharp definition at the expense of smoothness of motion (the key is to find the balance for each situation).

Martin French
May 19th, 2005, 09:16 AM
The 25P question is fairly obvious. It you want to shoot like film (a big reason for shooting in P mode) then film is shot at 24 frames per second with all the limitations that shooting at 24/25fps brings.

We shoot almost nothing but dance and in 25p mode the results are great but in 1/50 mode the only difference is slightly less blur or slicing depending on what you call it.

1/25 is a superb look for a lot of things and I really don;t think Canon set it that way because of a mistake they made.

M.