More Slow Motion Tests with Sony Smooth Slow Record
Since my last little slow motion test I’ve had plenty of quality time with my HVR-V1P, and while I wish it had a slightly more memorable model name - or even that it was printed somewhere on the unit, so I can tell people what it is when asked - I’m having a great time with this camera, enjoying the capabilities HD resolution gives me, and still loving Sony’s Smooth Slow Record feature.
With the last batch of slow-mo clips I had some requests to further slow down the motion in post-processing. I don’t currently have any 3rd party retiming plugins, but it turns out that the 200FPS (240 for NTSC regions) is shot interlaced, so my previous tests were only displaying 100FPS progressive. To get the full motion from 200FPS on a progressive monitor I needed to slow the footage to 50% speed and de-interlace, a trivial task in any editor.
Even this low-tech retiming gives you an idea of how powerful 200FPS can be. I actually had an ND filter in place to keep the shutter speed relatively low and keep a bit of a dreamy look for this shoot (the minimum allowed, of course, being faster than 1/200). With full sunlight you’d have no trouble getting up past 1/1000, which would result in very little motion blur and allow very accurate motion tracking, and some exciting retiming opportunities.
Keep in mind that this isn’t being captured at anything near HD resolution. The clips look fantastic scaled down to 400-500px wide, but at full size 1920px (or 1440×1.33 pixel aspect ratio, for the pedants) it shows very obvious artifacts from upscaling. It would be nice to have an option not to do this upscaling in camera and instead write the buffered pixels 1:1 in a cropped section of the video, but that could probably get confusing for end-users. I’ve attached some 1:1 crops to the end of this post, and uploaded some full resolution frames to flickr (1, 2, 3) for anyone who’s keen to look a little closer. Next step is to spend some time with a resolution chart to test the effective resolution in this mode.
More frustrating than the decreased resolution, and less forgivable: For some reason there is a pause at the end of every Smooth Slow Record clip written to tape. The motion pauses and the last 15ish frames are frozen. I’m sure there’s some technical reason for this, but it’s extremely annoying for editing, and mars an otherwise very enjoyable shooting experience.
More slowness to come. I don’t see the novelty of this wearing off too soon.
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Create Digital Motion » Slow Motion Pixels: Sony Smooth Slow Record Resolution Tested on HVR-V1P
[...] my last slow motion tests with my Sony HVR-V1P, CDMo reader FANF gave me some quick tips on how to run a resolution test. [...]
January 10, 2008 @ 11:16 am
Comments
Dan Winckler
Beautiful. Regarding the upsampling, etc — maybe I missed this in an earlier post — what resolution does it shoot at in 200FPS mode?
October 17, 2007 @ 4:27 pm
Jaymis
I haven’t found quantative information on what resolution is shot in 200FPS mode.
It writes to tape in 1080i, but looking at the 1:1 crops above it’s quite obvious that isn’t 1080 lines of resolution. It buffers either 3, 6, or 12 seconds at 200FPS and then writes this out to tape. I haven’t done any tests either to see if going for a longer record time results in decreased resolution.
Hence my desire for some resolution charts to try out, which will at least give us a close “analogue” reading of the effective resolution in this mode.
October 17, 2007 @ 7:13 pm
Francisco
Probably the last 15 frames issue is related to the Sony HDV GOP.
Wikipedia: “In HDV 1080i, one in every 12 (25 FPS) or 15 (30 FPS) frames is an I frame. In HDV 1080p, one in every 12 (25 FPS) or 15 (24 or 30 FPS) frames is an I frame. In HDV 720p, one in every 6 (24, 25, or 30 FPS) or 12 (50 or 60 FPS) frames is an I frame.”
http://en.wikipedia.org/wiki/HDV
October 18, 2007 @ 11:20 am
Reid
If you drop down to 720p, is the slow motion footage progressive?
November 9, 2007 @ 4:13 pm
Chad
Where is that music from? I know I’ve heard it before but it’s not in my library.
November 9, 2007 @ 7:02 pm
Jaymis
@Reid: The slow motion will only record at 1080i mode, this camera doesn’t do 720p, and “Smooth Slow Record” mode locks it to 1080.
@Chad: You should have waited until the end of the movie for the credits :) Music is Boards of Canada - Dayvan Cowboy.
November 9, 2007 @ 7:30 pm
FANF
Nice video !
For a resolution/definition test, I am very interested…
Now here is a little protocol for definition testing:
Get his first: http://www.graphics.cornell.edu/~westin/misc/ISO_12233-reschart.pdf
Print it 350 dpi min, 600 recommended.
Place it in a well lit spot, in the sun for example, fixed to the wall. Use a spirit level.
Place your camera with the optical axis perpendicular to the plane of the testchart (measure hight, use spirit level).
You should not see the white triangles on the underscanned image. No white triangle pointing into the image, the black triangles should ideally be pointing to the perfect edge of the screen.
To test the resolution/definition on the full breadth of the lens, do a test at wide angle, mid, and full tele, placing camera/testchart at the right distance for the scale to be right.
It would be equally important to test each focal at iris values 1.6, 2.8, 4, 5.6, 8, 11 to have a good idea of how definition rises and falls when you stop down.
To do this, use the “aperture prioriy” or “Av” program mode on your camera for correct exposure.
The definition of your camera, horizontal & vertical being distinct, is read by following the lines along the higher numbers ; the number where you cannot distinguish them from one another is your definition, in n x 100 lines.
(Make sure you zoom into digitalised footage to measure the image, and not your screen !)
I hope this post will have inspired some of us to do these tests, even to a limited extent.
In your case, Jaymis, I guess you could calculate the output definition of your camera in slo-mo by just comparing two shots ;)
Ref. :
http://www.bealecorner.com/trv900/respat/
http://www.gargul.com/IMG/pdf/pdvhd_cst3.pdf
http://www.cameravideo.net/forum/dv-technique-generale-video-audio/2225-tester-definition-dun-camescope-une-mire.html
(french)
November 10, 2007 @ 2:47 am
Ronny Wijaya
Is it only limited for 3 seconds in the real time world? If yes do you know any camcorder that has no limitation or longer?
May 15, 2008 @ 4:31 pm
Jaymis
@Ronny: It’s limited to 3, 6 or 12 seconds in the real time world (and the longer you shoot the lower quality, as mentioned in this article).
12 seconds gives you 48 seconds of slow motion recording through, which is rather a lot.
There is also the new Casio EX-F1, which should be able to shoot for much longer, and also doesn’t record to tape, which makes for an easier workflow.
May 15, 2008 @ 4:50 pm
Other Sites Linking Here
Sony V1 200fps Smooth Slow Record Testing at FreshDV
[...] Create Digital Motion has some super slo-mo example footage up, it was shot with the Smooth Slow Record function that is available on newer Sony HDV camcorders. “With the last batch of slow-mo clips I had some requests to further slow down the motion in post-processing. I don’t currently have any 3rd party retiming plugins, but it turns out that the 200FPS (240 for NTSC regions) is shot interlaced, so my previous tests were only displaying 100FPS progressive. To get the full motion from 200FPS on a progressive monitor I needed to slow the footage to 50% speed and de-interlace, a trivial task in any editor. [...]
October 18, 2007 @ 3:49 am
Sony Smooth Slow Record Samples - Digital Camcorder News
[...] Link [ via FreshDV ] [...]
October 24, 2007 @ 9:00 pm
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