View Full Version : shooting conference wi. EX1; how to shoot Powerpoint-screen wi. small camera?
February 12th, 2012, 10:16 AM
I'll be shooting a conference next Wednesday, and every presenter will be showing Powerpoint slides on a big screen to the right of the podium.
When I last did this, I trained my EX1 and Canon XF100 on the podium (different angles; one tighter than the other), and used my small Canon HF-S10 (also 1920x1080) to shoot the screen. My thinking was that I'd prefer to see the slides (in the edited version of the conference) as the audience sees them, rather than adding them after the fact, as pdf files... there's something about adding them as pdf files that looks fake.
The thing that didn't work with my strategy had to do with colour-temperature.
I had my EX1 and Canon XF100 white-balanced the same, but I wasn't able to do this with my small Canon... I can't, in fact, white-balance it... the only control I have over colour-temperature is setting it for sun, or shade or tungsten or fluorescent, etc.. I chose tungsten, looking at the lights overhead, but when I looked at this footage of the slides after the fact, it was all so very blue.
So before I shoot this next conference, I'd love some advice re how best to get footage of the screen where all these powerpoint slides will appear. Is there another way to set up the little Canon so that it will have a more normal colour temperature?
February 12th, 2012, 11:54 AM
What you're dealing with is the difference between the color temperatures of the room lighting compared to the projector lamp.
Most typical projector lamps will be in the daylight range.
If you never see the powerpoint projection in your other shots, then consider using daylight preset for the shot of the screen.
If you have wide shots that show both presenter and screen, consider mounting a color correction filter over the lens of the projector to get its color closer to that of the room. you might try an 85 filter (full CTO) or an 81EF filter (1/2 CTO).
While the projector may look too warm by eye, it should read better for the cameras. If using the 85 filter, put your projection camera to tungsten. If trying the 81EF, the fluorescent preset might be closer.
February 12th, 2012, 04:30 PM
I do seminars with PPS all the time. I shoot the presenter with 1 camera, shoot the screen with a pocket cam JUST for a referance point and then get the PPT from the client and drop in the slides as needed from the original Powerpoint presenatation. Since they aren't moving I can convert the slide to a PNG or JPG and drop it on the timeline where appropriate. Trying to shoot a screen that's running a PPS can be frustrating. I also remind the presenters to NOT walk into the screen as that can really mess with your exposure.
February 12th, 2012, 05:03 PM
Thank you Dave and Don for your replies. Very interesting. Dave, I'll check into the filters, because I do, in fact, include the speaker and the screen in my side-camera (usually my XF100 camera) shot (my EX1 is shooting from directly in front and is trained just on the speaker). Great idea.
Don, I've done it the way you describe, but to me this just doesn't 'look' as good. I'm really hoping to include full-screen shots of the slides in the same 1920x1080 size and with the same look and lighting as everything else, so that the edited version of the conference looks the same as it did 'live', for those who were in the audience. And if I can do that, it doesn't matter if someone walks in front of the screen, or raises and arm to point at a sentence or diagram on the screen (which happens a lot I find), because the action on my XF100 side-shot and the cu. screen-shot match perfectly.
By the way, Don. Have you heard about some software called Presto? Unless I'm wrong, it substitutes PP slide images into the presentation in a way that sounds kind of neat and different. Works with Final Cut Pro and not Avid, though, so I haven't tried it.
Dave: one more question. If I can't make the filter thing work (maybe the conference organizers won't want me to touch their projector...) and I set my small Canon to daylight, wouldn't this be an improvement? If the small Canon shot of the screen would be quite a bit less blue then I think it would cut so much better with my XF100's side-shot of the presenter/screen...
February 12th, 2012, 05:15 PM
Remember, if you shoot the screen with more than one camera and those cameras are set to different white balances, the color difference of the screen in the different shots will be distracting as well. Hence if you can make it look good in the wide shot, match to that.
February 13th, 2012, 08:33 AM
Is there a reason why you need to shoot the PPT on screen? I believe there's a software that captures PPT presentation and tags slide changes for easier synching during post.
My 2 cents
February 13th, 2012, 03:41 PM
I personally prefer to drop in clean copies of the slides onto the timeline afterwards having exported them from Powerpoint. Pointing a camera at a projector screen is always unsatisfactory IMO.
If you must do it, ensure the camera is set up to cope with the peak white level on the screen and the shutter rate matches what the projector is running at.
February 13th, 2012, 04:44 PM
Sounds good. I'll give it another try, the day after tomorrow (I'll use a filter if they'll let me, otherwise I'll go daylight on my small Canon) and see how it looks. I can always resort to your method, Marcus (and Don's method) if I need to.