Unusual video noise
HI....I recently shot an indoor speaker with a power point presentation behind him. I had to set my Canon tape camera to 6db to balance the lighting ratios correctly. When viewing the final edit in the canvas, it looks fine. But when I output to a full QT, it is looking unusually "noisy". I shoot a lot of ballet at 6db with out this issue. Could there be something else going on with a setting perhaps, or even my camera?
Image is probably overdriven.. can you publish a still and/or a screen shot of the waveform display?
Hi Mark... here's a screen grab from the footage, and a viewer scope image as well. Hope the captures are good enough. The man in front of the screen looks worse on my iMac than it does on the Cow for some reason.
When you say over driven, is that in regards to my camera settings or something in FCP 6.06 - that I have set wrong? FYI, I don't use compressor when I write a QT file... I just click on export to: Quicktime Movie.
Thanks for the reply
The QTX screen grab is not much useful.
Better do one in QT.7 (you should have it installed, if you don't have it, do it).
Although the picture looks very dark (the speaker mostly), the FCs scope shows that the blacks are not crunched at all, but the opposite.
Also the highlights on center of the picture looks blown-up, while the scope shows that in fact there are very low.
Again, the picture do not match with the scope. I only can think that QTX is displaying very bad the image; like if would be making an auto-contrast (whites up and blacks down).
You are probably right, Rafael: I was expecting to see the scope off the scale and the whites completely blown out.
Yeah, beside the noise issue, the picture needs some color correction.
Bringing those blacks to his correct level probably will make disappear any noise.
Well thanks guys, for all the good advice and observations. I do have QT 7, but maybe I should have pulled a still directly from the QT window itself, instead of using the utility "GRAB".
So from what I gather from Rafael, I need to crunch the blacks some more, and try to do something about the highlights?
The client originally wanted me to simply show up, tape this live presentation that he would edit himself. Problem was, there were all sorts of lighting, sound and camera positioning mistakes.
He originally had me at about a 40 degree angle to the screen. Now the perspective was all wrong. Thirdly, practically all the auditorium lights were all up. As a result, the screen could not be seen very well.
I had to go though a quick technical explanation to correct this - and instructed the lights to be brought way down.
I arranged for (2) grid lights to be put on the speaker - only. I actually preferred the speaker a little darker in relation to the screen, but had to compromise at best. Getting him exposed along with a 'too bright show' was a little tricky. The PowerPoint just had too many highlights blown out.
Jonny, you probably know this already but I like to mention it in case future readers come across the thread:
There are a couple of ways to deal with shooting the single-camera Powerpoint hell scenario.
My number one rule is that the powerpoint is generally recoverable later, the speaker is not, so always favor the SPEAKER with the exposure and lighting optimized for them, NOT the screen.
Right after the presentation is done, have the presenter or an assistant click thru all the slides again, one second per slide, but this time expose for the SCREEN. In post you will be able to replace the screen, and BOTH screen and speaker will be properly exposed. An alternative method is to have a large capacity flash drive on your keychain and go before or after the presentation and plug into the laptop to make a copy of the ppt show. The resolution of the actual slides will be far greater than even well-captured camera footage of the screen. And really, it's 2013, and people are still capturing slides by optically recording their projection off a screen under crappy conditions... when they really don't have to.
"But Mark," you say: "what if the presenter partially eclipses the screen or uses a laser pointer on it or something?"
Well, often this won't matter, if the screen is already blown-out white from you exposing for the speaker, then using the proper blend mode and corner-pinning the slides in post, it should all line up just fine without any need for roto, at most you might set one garbage mask and activate a luminance keyer. *Maybe*. You also have the opportunity to do Picture-in-Picture effects with two boxes up on your 16 by 9 video screen, with the speaker in one and the slides in the other, and room below each for nice character generated fonts and a high end-looking background texture or motion loop. Turn low quality raw material into a more high-end look this way.
One other way I handle this in the one-camera situation:
Using the auto-iris, but manually snap-zooming, I wait for the right pause in a statement and snap from the speaker to the screen full-frame and as soon as I have it in focus and auto-iris has the exposure, I manually yank it back to the speaker. In post, I turn that momentary closeup into a still of any needed duration and slide the start point backwards a couple seconds to cover the initial camera change. This gets me the effect of a 2 or-3-camera live-switched shoot, using just the one camera.
You have to listen to the rhythm of what the presenter is saying, to time this right. They normally follow a pattern of stating the idea, going into some depth, then summarizing the idea again. If you listen for the micro-pauses between these ideas, you can use that interval to change the shots very fast with manual snap-zoom and re-framing, covering the beginning and ending of sections with full-screen slides, and the meat of the idea with the close-up of the presenter... and not lose anything substantial in the audio at all. I tend to go like this: Wider shot speaker, cut to full frame slide just long enough to read, cut back to medium or tight on speaker, cut back wot wide shot as he finished, use the slide to cover if needed.
Repeat for next section.
But you can't just be a passive shooter and do this, you have to stay fully engaged.
Finally, arrive early before the start time and get as much cut-away b-roll of the assembled audience as you can, in singles, 2-and-3-shots, and a few rack-focus pulls. Do it from the speaker's POV position, hand-held, and from your tripod. Get one really zoomed-out wide shot as well, the screen need not be legible for this. These little cut-aways will add life and interest to your edit as well as cover mistakes or other edits.
Bad enough people communicate with powerpoint. The least we can do is make the best of a bad thing.
Well, it's video, and video does NOT have the same in video levels as a computer, and it shows in the screen grabs.
Your screen grabs reveal that that aside from a couple of problem areas, your image is largely underexposed. I would think that using 3-Way Color Corrector would go a LONG way toward fixing the overly-bright spots, raising the overall luminosity and bringing black into the realm of black.
What about noise? That's why The Good Lord made Neat Video. Or inspired the people who made Neat Video.
Former Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Wow....great information from Mark, Rafael and Dave!
Yes, had I known what was coming my way, I would have dealt with this in any number of ways as Mark suggest; expose the powerpoint on one take and then the speaker on another. Or just shoot the speaker and put the powerpoint show on a thumb drive and built it in FCP. I simply had to make a fast decision to do this shoot all in "one take"... all 55 minutes of it.
At the time, I thought the simple way out was to set exposure for the show, and then set up grid lighting up on the speaker. But due to the light to subject distance, the grid lighting was not powerful enough to bring it up to a 0db camera setting, so I had to lower the db and try to get both. That in itself was not the sole problem, but still a convoluted way of going about it.
Mark's suggestions would have been better. Moral of the story is: I should have acquired more detailed information from the client beforehand. I had no idea a PP show was involved. I thought it was just a lonely ol' speaker by himself.
I don't have Neat Video Dave, and it certainly it sounds like a good plug-in to me. So at this point, I have crushed the blacks more and it has improved the noise to a [perhaps more] acceptable level.
Thanks to all again...