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The Canon C300 is of interest to me as a potential “workhorse” video camera (replacing my current EX3) for both cinematic projects and live events (incidentally, after having written that sentence, I reassuringly found the same phrase uttered by Philip Bloom, so hopefully I’m on the right track here).

Cinematic projects in particular can benefit from more controllable DOF and both can benefit from light sensitivity, while the live events (indoor or outdoor) in particular can benefit from latitude.  Of course these things are handy in general, but those are the occasions when I’ve felt they were lacking in the past.

The C300 addresses most things, apart from lack of 10-bit output.  Hopefully I could trade-up to that in a couple-or-three years’ time when Canon upgrade to that.  And investing in “glass” (lenses) for it is probably a better investment than external recorders (buy or hire) for my current EX3.  The price stings a bit though, so I won’t just leap into it.  I’ll definitely begin by hiring/renting.

My Canon C300 research-in-earnest begins here with a (great) review I initially heard about (via private IOV forum).  That’s the UK’s Institute of videography by the way.  Here:

• Video (fun & informative): http://vimeo.com/32067654
• Text:
  • Overall Camera: http://learn.usa.canon.com/resources/articles/2011/c300_for_cinematographers.shtml
  • Log Gamma: Understanding the EOS C300’s Canon Log Gamma
  • DIT / On-Set Data Management: On Set Data Management with the EOS C300

The following thread at DvInfo includes rolling-shutter-provoking tests (flash, jerk-motion):

•  http://www.dvinfo.net/forum/new-canon-cinema-eos-c300-c300-pl-cameras/503089-c-300-footage-commercial.html

The main points about the camera (for me at least, and not in this particular order) are:

• Ergonomics / practicalities:
  • Better (some say) than the F3.
  • Weatherproof, sensor-cooling
  • ND Filters (three) in-camera
    • Seems fairly unique in this kind of camera
  • Handy proper buttons for Zebra, Peaking, Magnified views.
  • LCD and button-panel orientate in various directions.
  • Fits on a standard DSLR rig.
    • But Zacuto supply a tailored rig.  CVP are among its agents.
    • And there’s Redrock’s inspiringly-named UltraCage.
  • Solid construction, feel and mounting threads, better than “single central bolt” like many cameras have.
  • Wi-fi adaptor transmits a low frame rate version to your computer. If the lens is set to autofocus, you can actually change the focus remotely.
    • Wifi controller is an additional item - not part of the basic package
  • Battery lasts 5 hours
• Sensor
  • Latitude (recordable, depending on settings):
    • Quoted as “13+ stops in the field”
    • But there is uncertainty over this, since apparently <<Canon thinks that with their Canon-Log color space, the camera allows “800% overexposure… which translates to …an Exposure Latitude of 12 f-stops.” Graeme Nattress of Red disagrees.>>>
  • Less noise, moire and jello than 5D Mk.2 etc.
    • Noise & moire reduction largely result from 4K sensor + DSP to HD.
      • Moire tends to result from significant interpolation inherent in less dense sensors
  • The “less noise” hence less need for low fstops (coupled with smaller sensor than 5D) means greater DOF (the antithesis of the 5D).
    • Greater DOF is preferable at times, for practical as well as aesthetic reasons (when you want to see the background).
• Lens Mount
  • Camera comes in two lens-mount varieties, not interchangeable:
    • EF-Mount for Canon lenses (ordinaire & “CN-E”).  This is the one for mortals like me.
      • Permits iris to be controlled via dials on camera.
      • Greater available selection of lenses (also usable on stills cameras) e.g.:
        • Telephoto: “EF 70-200mm f/2.8L USM” telephoto zoom lens and tilt-shift lenses.
        • Macro: “EF 100mm f/2.8L Macro IS USM” (article photos include an image of ants)
        • Fisheye: “EF 8-15mm f/4L Fisheye USM”
        • TiltShift: “TS-E 90mm f/2.8″
      • Image Stabilisation (IS) is reported to be good e.g. with the Canon L 70-200mm F2.8 IS Version II
    • PL-Mount: More for movie professionals.
• Recording:
  • Resolution: HD 1080p & 720p
  • Frame-rates: variable 1 to 30 fps in 1080p mode, and 1 to 60 fps in 720p mode, 1 fps increments.  Also time-lapse and stop-motion/claymation (latter is several frames per “click”).
    • But, like F3 (and unlike FS100), overcranking requires dropping to 720p
  • It can also shoot 50i and 60i (interlaced), useful for deriving 50p and 60p in post.  Historically (e.g. for DV or HDV (Z1) footage), I have done this using freeware (AviSynth and its TDeint filter) for this, but Apple Compressor and other alternatives exist too.  Stu Maschwitz apparently covers this topic in his book << The DV Rebel’s Guide>>
  • Gamma: includes Canon’s Log Gamma.  LCD & V/F display flat and corrected.
  • Audio: uncompressed 16-bit audio at 48 khz (info from FAQ).
• Recording format:
  • Compact Flash (over 5 hours for a 128GB card)
  • MPEG-2 Long GOP 4:2:2 MXF codec with a constant bit rate of 50 megabits/sec.
    • Philip Bloom says ”It is the bare minimum for HD acquisition, but it at least reaches it.”.
    • Sample recording (MXF as stated) is available here (according to here).
    • {Does MPEG-2 imply 8-bit?}
      • Yes.  That is highlighted in several other sites e.g. this and this.  Some believe (rightly or wrongly) that this limitation is a “corporate rather than technical” decision, and a future generation will have 10-bit.
    • {What of the Log Gamma? 8-bit (is it ?) would limit its usefulness or not?}
      • Opinions differ.  Obviously the extent to which it matters depends on the scene.  Some views and image comparisons are here, for 10, 8 and even 7 bits.
        • At that link, one poster suggests dithering as a work-around to reduce banding (from any camera): adjust camera to give noise then (in post) use a good noise-reduction plugin.
    • The only Super-35 sensor camera in its price category (as of fall, 2011) that records 4:2:2 color sampling on-board.
• Ports:
  • XLR (via clip-on monitor assembly?)
  • Time code, Genlock, HD/SD-SDI and HDMI
    • {But how many bits? 10 (as I’d hope) or still only 8?}
      • Only 8-bits, surprisingly.  It is reported that: “SDI output (is) limited to 8-bit 4:2:2″
• Monitoring
  • RGB histogram, vectorscope and an Edge monitor (focussing)

More links:

• Wikipedia: http://en.wikipedia.org/wiki/Canon_C300
• DvInfo Article: http://www.dvinfo.net/article/acquisition/canon-eos/canon-usa-announces-cinema-eos-c300-and-eos-c300-pl-cameras.html
• A demo video at ISO 16000: http://wideopencamera.com/cameras/canon-c300-16000-iso-with-canon-14-5-60mm-pl-zoom-lens-footage/
• Vincent LaForet’s short-film (and making-of), using that camera http://blog.vincentlaforet.com/2011/11/03/mobius-and-the-c300-c300pl/
• Article by Stu Maschwitz (creator of Magic Bullet and author of book “The DV Rebel’s Guide”): http://blog.vincentlaforet.com/2011/11/03/mobius-and-the-c300-c300pl/
• http://provideocoalition.com/index.php/awilt/story/quick_look_canon_eos_c300_lss_1080p_camcorder/

Other Misc. Links:

• http://www.bjp-online.com/british-journal-of-photography/news-analysis/2127270/movie-debut-canons-c300-camera-created
• http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=789380
• CanonRumors: http://www.canonrumors.com/category/photography/canon-c300/
• Canon Links:
  • http://www.usa.canon.com/cusa/professional/standard_display/cinema_eos_system
  • FAQ: http://learn.usa.canon.com/resources/misc/cinemaEOS_faq.shtml

For action scenes like fast ski-ing, what shutter speed is best?

• http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/472066-ski-race.html
  • In general, for action scenes, reduce shutter to 1/125, no faster.
  • However some find even 1/125 gives “amateurish” feel, and prefer motion-blur, hence recommend 1/60 (for both 30p and 60p footage).

The traditional degree of motion blur, broadly consistent with what the eye normally experiences, is obtained by using around 1/50 sec shutter (no problem in practice for shutter speeds 1/48-1/60).  What shutter setting (mode /value combination) can best achieve this for different shooting modes, e.g. 25p, 50i, 50p ?  I am no expert on this but from my web-search I assume the following:

• For progressive modes around 25-30p, where light level allows, use Shutter On.
  • But for double-rate progressive (50p-60p),  use shutter-off.
• For interlaced modes or double-rate progressive or for low light situations, use Shutter Off.
  • In interlaced modes, Shutter Off is equivalent to 1/50 or 1/60 (depending if 50i or 60i)
• Warning about Angles: in Interlaced modes, “180 shutter” acts more like a 135 shutter.
  • The “Angles” option is really aimed at film veterans, who by definition only use progressive.

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On an EX3, what’s best for indoor shots of lectures etc?

• Normally film runs at 24fps, with a 180° shutter - which is 1/48th second.
  • Hence for 25 fps, ideally use 1/50 second, or nearest available match to this.
  • Uncertainty: For 50i, each field is at 25fps, so presumably still use 1/50 second ?  Depends on how camera works?
• For a shot of someone talking, it would be hard to see the difference between a 1/48th shutter time and a 1/60th shutter time.
• To avoid (conventional) light flicker, frame rate should divide by integer into twice the power frequency.
  • EX3 has no 1/50 shutter speed, at least when specified by Time - nearest equivalent is 1/60.  This may risk some degree of light-flickering in 50Hz mains countries.
• For 1080i50
  • Initially, used “No Shutter”, to maximize exposure with least Gain.  But gave noticeable motion-blur.
• For 50p or 25p
  • 1/50 or nearest equivalent (on EX3 is 1/60)
• For 50i, opinions vary:
  • UseEX3’s nearest equivalent time-based shutter time of 1/60
  • Use 180 degrees (assumes this angle relates to frames-per-second, namely 25fps for each frame - but is this valid when interlaced)
  • Use No-Shutter (assumes 50i shoots each field alternately, at 50fps, hence no-shutter is inherently 1/50 - but is that assumption true?)

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Which is best?   Depends on the camera, scene and shot dynamics I guess.  The same point is queried at the following thread:

• http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/238593-steady-shot-smoothcam-both-what-2.html#post1551809

Some general advice from a computer-post-savvy author: definitely use the camera’s SteadyShot:

• http://www.gcvcc.com/March%202008%20%20Camera%20Techniques%20No2.pdf

Limitations of post

• Stabilization necessitates motion estimation and image reconstruction, which are extremely CPU-heavy, hence really slow to execute.
• Most stabilization apps (in post) can’t currently cope with motion-blurred edges or parallax effects (though both should be possible in principle, by deconvolution and 3D modelling both informed from multiple frames).
• For rolling-shutter-ed footage (e.g. CMOS sensors as in Sony Exmor as in Sony XDCAM-EX e.g. EX1 & EX3), there exist options to reduce the effect (don’t expect perfection, but may suffice):
  • Sony’s ClipBrowser 2.6 can remove this http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/467511-clipbrowser-takes-out-rolling-shutter.html.
  • Gunnar Thalin’s Deshaker plugin for VirtualDub can compensate for this.

My experiences:

• Stabilizing Tools:
  • Gunnar Thalin’s Deshaker works really well.  And it is multi-threaded, really speeds up the process.  The author says it is more intended for handheld pans etc. than fast-shaking shots from vehicles etc. (but has nevertheless seen good results in such situations).
    • The author says [http://forum.doom9.org/showthread.php?p=1418923] to try “to stabilize only on the most distant parts in the frames, since the moving inwards-effect is less there”.  And “you should probably increase the value for [discard motion of blocks that move > X pixels in wrong direction]. That’s to allow the blocks to move “freely” a little, since Deshaker can’t handle the “moving inwards”-effect.
    • Possibly equally applicable to other smooth/stabilize/deshake tools ?
  • Boris’s Optical/Motion Stabilizer (in Boris Red 4.3.3 on XP) is only single-threaded and I find it slower, clunkier and less intuitive than Deshaker.  Has a Smooth mode, which is like the others here, as well as a Stabilize mode (try to keep frame static, no good for motion then).  The other tools can be configured to do the same thing.
  • Mercalli in Sony Vegas has no mode for 720p50 but otherwise is pretty good and very intuitive and configurable.
  • FCP’s SmoothCam Effect worked best for a challenging clip for wobbly-hand-held camera tracking close past an object (a Formula-1 car) hence huge degree of moving-inwards effect.  The default settings worked straight away.  The result quality was way above that of the other tools.  On the other hand sometimes it’s not the best (sorry, forgot the exact situation).
• Cameras & Shots:
  • Historically, using a TRV33 DV HandyCam indoors (hence low-light hence long shutter time):
    • Way back in the past, using a (now ancient) TRV33 DV handy-cam (which has huge sensor margin i.e. spare pixels), when I shot big zooms to lecture audience individuals (e.g. question-time) I had the camera’s steady-shot (digital, not mirror) enabled  and used Gunnar Thalin’s Deshaker (VirtualDub plugin) also.  The result was astoundingly steady.
    • The same arrangement worked OK with hand or shoulder mounted cam for walk-throughs past nearby objects (e.g. walls, people, furniture).
    • An attempt to do the same thing without steady-shot enabled on the camera resulted in seriously motion-blurred edges.
  • Now, using a Sony EX3:
    • With camera Steady-Shot set to Medium, hand-held pans and motion past nearby objects seem to acquire a positional instability, as if the camera feedback mechanism needs greater damping. Maybe the camera’s internal mirror “suspension” has to be tighter (than the TRV33 digital equivalent) because it lacks the generous pixels margin of the TRV33?  or maybe something to do with the mirror’s inertia?  Or (real-time-constrained) processing-power?
      • Experimentation is needed with the camera’s other SteadyShot modes (High, Low).
      • In the absence of more generous sensor pixel margins, I wish it could be loosened-up e.g. to allow black borders (to crop in post) so as to permit smoother rides overall.

Great sequence of images tally with my general experience:

• http://regex.info/blog/2010-01-25/1436

Basically:

• 1/100  looks slushy, grey and indistinct “cords” (not flakes/lumps)
• 1/500  looks crisp - can see individual snow flakes/lumps falling

Also, from my own experience,  is best to focus on 2 metres or so away.  Focus matters since DOF small when aperture maxed as one may do to allow max shutter speed (depending on lighting conditions, most likely overcast)