On 2017-06-27 13:26:37 (+0200), Wouter Verhelst <[email protected]> wrote: > On Tue, Jun 27, 2017 at 12:51:40AM +0200, Nicolas Dandrimont wrote: > > Hey all, > > > > I've spent an evening and a day working on video stuff last week-end, using > > the > > opportunity of a pair of lent cameras to do some work. I've put some > > pictures > > up at https://krkr.eu/dcvideo/ > > > > Here's what I can report: > > > > Camera testing > > -------------- > > > > I had both the Sony PXW-X70 and the JVC GY-HM200E set up. Both cameras are > > largely similar in functionality and feature set, and they work just fine > > with > > the vocto setup. > > > > I recorded to YouTube : https://youtu.be/BleLh5hXICY; at the beginning of > > the > > video, the JVC is on the left, the Sony on the right; I switched them out > > at 12 > > minutes : most of the video has Sony on the left and JVC on the right. > > > > The differences I could notice were: > > > > - Low light behavior: using dawn and the blinds in the room allowed me to > > test > > for crappy light conditions > > > > (reminder: at those timecodes, Left = Sony, Right = JVC) > > test 1 : https://youtu.be/BleLh5hXICY?t=9282 > > test 2 : https://youtu.be/BleLh5hXICY?t=10293 > > > > feel free to stroll through that video for more tests. > > > > What I noticed: > > > > The JVC high gain for low light setting is manual and fiddly; Sony has > > proper > > automatic gain control. The JVC's auto white balance is slow, the Sony > > seems to > > do the right thing pretty fast even in very bad conditions (playing with > > blinds, light switches, ...). The JVC also was very grainy when fully > > zoomed in > > and in low light (see the very beginning of the video). > > In addition, the JVC's autofocus seems pretty bad, often requiring > several seconds to be done; the Sony seems faster in that regard. > > Its grainyness is due to the larger sensor on the Sony; that's perfectly > expected behaviour (and is why my friend suggested the Sony in the first > place). > > I notice that the JVC seems to be able to zoom in further; is that a > correct assessment? Given that it has a smaller sensor, this is also to > be expected; but given that the Sony's sensor can do 4K and we only need > 720p, we can probably get away with so-called "digital" zoom without > that much quality loss (there will be some optical artifacts, but not > really something you'd call showstoppers) > > Did you run a test on how far away you can get a close-up of someone? > > > - Size: the Sony is substantially smaller than the JVC and we should be > > able to > > fit two in a case the size of the ones we've been using for the dvswitch > > laptops. > > That's good, yes :-) > > > - SDI connectivity: the Sony does SDI-6g (up to 4k) while the JVC does not > > (AFAICT, pegging the SDI to 1080p). Not very useful for us, but who knows > > what we'll do in the future... > > Right, but I doubt we'll ever want to do more than 1080p (if even that), > so it shouldn't matter at all. > > > - Audio input setup: I only had batteries for the tests (no AC adapter) and > > I > > noticed the Sony would lose audio input settings when rebooting. As it > > defaulted to shoe mic it's not a showstopper. > > It is a bit annoying, and might be confusing. There is a slight risk of > people switching off the camera and thereby losing settings, resulting > in the recording not being the way it should be. > > I agree it's not a showstopper, but it is something we need to make sure > we've got covered for volunteers; we should tell them never ever ever to > switch off the camera, or have a cheat-sheet of "post-boot operations" > with every camera. > > Probably best to do the latter, actually.
Rather than routing the audio through the camera, maybe just get something like this: https://global.focusrite.com/usb-audio-interfaces/scarlett-2i2 or a version with more interfaces and feed the audio directly into the mixer PC. I think this should also make cabling a little easier. Using a version with more inputs, would also allow us to feed the environment audio directly into the mixer PC, simplifying the audio mixer setup. Peter. _______________________________________________ Debconf-video mailing list [email protected] http://lists.debconf.org/mailman/listinfo/debconf-video
