My Apple Watch 6 has a sound pressure meter built in. It measures the decibel levels in your immediate environment. I'd glad I had my earplugs in and my headphones on last night because 50 feet or more from the main stage of the outdoor concert at the theater the SPL was peaking up around 96 dB. My watch kept prodding me trying to make me understand that continued exposure at those levels could result in permanent hearing damage. A good thing to know. But I kept asking "Siri" to tell my watch that I was using ear protection devices and not to worry so much. My watch must not speak Siri because it kept warning me at intervals.
External monitors
I've been having a love affair with two different external monitor/recorders this week. One is my older Atomos Ninja Flame and the other is the smaller and newer Ninja V. When I shoot video at the night time concerts, outdoors, I use the Ninja V clamped to my tripod leg and connected to my GH5 or S1H which provides me the ability to punch in and see the video in much greater detail for more accurate focusing while I am recording. You can't do that directly on the cameras. They won't punch in if you are already in the process of recording. The best you can expect from your hybrid video camera is to be able to set and see focus peaking indications. I want both. I want to be able to see the image writ large, with more magnification than a standard screen (100%?) and also see that magnified image augmented with the glimmering color indicators provided by focus peaking.
If I can already see the focus peaking artifacts on my camera screen why would I also want them on the monitor? I guess it's a matter a visual discrimination. On the smaller screen the focus peaking indications are closer together and it looks like much more is in focus than I'll end up with when I finally view the video on a large monitor at home.
If I can magnify the view and the see focus peaking generated by the larger monitor I'll be able to see the plane of sharp focus shifting more easily while I focus, as indicated by the dancing colors. The higher the resolution of the monitoring device (and the bigger the image on the screen) the better I get at hitting sharp focus. Having the image on both the camera monitor and an external monitor means I can turn on focus peaking on both and I can use different colors for the peaking. It doesn't do anything different but it's fun.
In casual use the focus peaking on most cameras is good enough to get you into the ballpark but not good enough to help you achieve super sharp focus with fast aperture lenses. Or fast moving subjects. Or with darker scenes. But the trade-off is that there's some lag time between what you see on the external monitors and what you see on the camera monitor. You have to change focus carefully if you are judging via the external because you'll get impatient and overshoot correct focus while you are waiting for the screen to catch up. Small corrections done in short increments seem to work best.
One thing I didn't think about in using either an internal or external monitor is the effect that a moving subject will have on the focusing indicators. I noticed last night that when my subject moved from left to right or vice versa the indicators vanished or diminished during the move. I had to wait for her to settle before I could re-focus and use focus peaking to help. At some point a fast moving subject, in concert, requires some careful anticipation.
Last night I fell into a certain rhythm. I'd try to get focus peaking indications to show prominently on my talent's microphone and then tweak just slightly behind it. I'd monitor the full frame on the camera's screen and the use the external monitor punched in to 1:1 to fine tune the focus. That worked pretty well for almost every shot except for the ones where the talent was moving all over the place. Fortunately she was moving perpendicular to the camera so the change in distance was minimal and the need to constantly refocus wasn't there.
The camera was set to 30 fps and I can imagine that focus peaking might work better at 60 fps since the underlying shutter speed would be faster and induce less blur. I'll try that next time I have a scene with more light in it.
Now that I've used an external monitor for a number of night concerts, with much longer lenses I can't imagine trying to shoot without one. But I said pretty much the same thing to my assistant during our still shoot the day before. There's something great about handing your client a 7 inch monitor at the end of a 10 foot HDMI cable while you are positioning a product or model and letting them see "exactly!!!" what your camera sees. It eliminates so many misunderstandings about physical point of view.
There's another thing I want to share about using Atomos Digital Recorders as simple monitors, running off batteries: Take out any SSD drives that you may have inserted in the drive bay. While the recorders are just set up to record video, as triggered by the video start button on your camera, they seem to know when there is an SSD inserted and they fire up their recording circuits, fan cooling, etc. in preparation. With a drive inserted they can blast through a big, fat battery in an hour and change. If you don't have a drive inserted the units can run for at least a half day and, with judicious shutdowns during scene changes, perhaps even a full day.
One warning about external monitors. One of their amazing abilities is the lumen power to produce a very bright image. This is great for working in full sun. And on film sets (video) people tend to work carefully enough NOT to judge correct exposure just via the monitor image. They mostly use a waveform or even a light meter to set overall exposure. The very bright image of the external screen tends to push sloppy users to underexpose their files based on the bright image they are seeing.
Of course, you can always calibrate your external screen to match levels with your camera's screen but that presupposes that you've been able to calibrate that screen! I think it's still best to use the waveform monitor in most situations. I've found that on a very dark stage it makes the most sense, when possible, to walk up onto the stage and take a series of incident light meter readings at the positions that the talent will be in. With a good cine meter and good technique (presuming the lights don't change much) you'll have a much more accurate starting point. Handheld meters are not dead yet.
I like the bigger screen of the Ninja Flame but the smaller Ninja V is just so convenient. And a lot better at conserving battery power. These monitors can also be daisy-chained so you could run one off the camera and use it close to the camera to really be able to see your scene in glorious detail. Then you can run a second monitor out of the first monitors "out" plug and set up that monitor as far away as you need in order to provide a safe, social distance, between you and your client. It's a good rationale to not trade in an "obsolete" monitor as you upgrade. You'll nearly always find a new use for a recent tech monitor. And anything you can do to make your set safer and more efficient is its own reward.
Finally, all the professional monitors either come with a shade or there is one available for your model. I think it's a great idea to get into the practice of always using the shade for a couple of reasons. First, it shade the screen from glare and glancing, non-image forming light. This makes the screen easier to see and your assessment of comp and color better. Secondly, if you are shooting a concert with an audience all around you then the shade is doing a great service for the audience by keeping the screen's light from being obnoxiously visible to all the people on either side of you and a lot of the people behind your camera position. Less light spill is just a nice practice to get into.
When I complained about the micro-HDMI plugs on some cameras I was channeling my experiences last night in setting up a camera in near darkness. I was guessing about the exact location of the camera plug and I was a bit rough with the cable. As the port was a full sized HDMI it's rugged enough to take a bit of abuse from time to time. Not necessarily so with the smaller connectors.....
That's all I've got for now.
3 comments:
Novice question: is a waveform monitor the same thing as a histogram?
@Mike
A histogram averages the total light in the full picture and plots it from smallest values to largest intensity.
A waveform averages the light intensity of each column (the vertical) in a photo and plots it along the horizontal. So you can see that the right might have a lightbulb off the chart and a black suit on the left. Whereas the histogram might just average the whole thing to the middle.
A photograph is the light intensity at each pixel, giving you the vertical and horizontal. But then you have your image.
That's a pretty good explanation. Also a waveform can show you what's on the other side of 100% or 0% which lets you know how far off your exposure might be. But David is right, a waveform tells you the light intensity geographically across the frame. Much more useful information. Maybe we should do a blog post on waveforms and vector scopes. I'll work on it.
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