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Jon Fairhurst May 21st, 2013 04:51 PM

Best inexpensive green screen camera
 
In general, I dislike "best camera" threads since "best" depends on the application and budget...

Okay, my application is green screen improv work and the budget is under $3k. A lower price is better, of course, and I'm willing to buy used. Also, I already have 35mm lenses, so that could affect the system cost.

As a 5D2 user, I'd consider the Magic Lantern RAW solution, except for the improv requirement. RAW bursts could work for well-rehearsed performances, but not for "let it roll" improvisation.

From my research, the Canon XF100 looks like a good $2,500 option. It records 4:2:2 1080p24 at 50 mbps. It's not very good in low light, but that's not a problem for a good green screen setup. It's MPEG-2, which means it's limited to 8-bits, so it's not ideal. Also, it uses a 1080p Bayer sensor, so it might not have the best possible resolution. The camera was released in 2011, so there may be some availability on the used market.

The BMC Pocket camera looks interesting at only $1,000. It records Prores 4:2:2 (HQ) at 10 bits. I can use an EF to MFT lens adapter, so I'm set for glass. Again, it uses a 1080p Bayer sensor. It's not available until July - at best.

I've heard that there are 4:2:2 hacks for the GH 1/2/3, but I'm not sure that's really true.

There are other cameras with 4:2:2, like the PMW-100 and EX1, but these cameras are out of budget.

So it looks like the XF100 is the best near-term choice with the less expensive BMC Pocket being potentially better (with 10-bit color) after it ships.

Back in the RAW domain, the original BMC is worth considering. With a 2.5k sensor, it will have higher resolution. It's got an EF mount. It records 12-bits. It's just barely in budget. Storage costs will be higher with this solution than for the XF100 or BMC Pocket.

Are there any other good, inexpensive, long-record-time, green screen cameras that I'm missing?

Also, any experience out there with the XF100, BMC, or other good candidates for green screen use? I assume that the 50 mbps 4:2:2 and 12-bit RAW specs will work well, but practice and theory are different animals.

I know I'm not alone in wanting a good, inexpensive green screen camera. Hopefully, this thread will be helpful for many here at DVInfo.

Ruben Kremer May 22nd, 2013 03:39 AM

Re: Best inexpensive green screen camera
 
Just to complement some of your info - the Blackmagic Pocket will also be shooting Cinema DNG RAW, as well as ProRes - just like it's 2.5K and 4K siblings.

So the data from the Pocket won't be that much less than from it's 2.5K brother, since 1080p is just under 2K, the files from the 2.5K cam will only be around 33% bigger than those from the Pocket.

Chris Medico May 22nd, 2013 05:14 AM

Re: Best inexpensive green screen camera
 
3 chip cameras such as the EX1 have advantages over single imager bayer sensors. You should be able to find a nice used one very near your budget.

Jeff Pulera May 22nd, 2013 08:39 AM

Re: Best inexpensive green screen camera
 
Another take on this - rather than limiting your camera choices to one that records in 4:2:2 directly, and still adds a good deal of compression, consider an outboard recorder. The Atomos Ninja 2 is now under $700 and accepts the uncompressed HDMI signal from any camcorder, and many DSLRs also.

Records direct to ProRes or AVID DNxHD codecs at bitrates of 100 to 220Mbps, so a much higher quality than just about any camera memory out there. But you can use a less expensive camera, even an older HDV model, and record full 1920x1080 4:2:2 video at high bitrates, great for keying and compositing.

Another option for studio work is to simply record the live camera output to a computer. Using an inexpensive capture card from Black Magic or Matrox, record the camera output (pre-compression stage) as uncompressed, or mildly compressed 4:2:2 format at high bitrate. Ready to edit. Again, better quality than almost any camera can do internally.

Thanks

Chris Medico May 22nd, 2013 08:52 AM

Re: Best inexpensive green screen camera
 
Remember that many of the HDV cameras had less than full HD sensors. They used upscaling to get to the final HDV resolution (and upscaled even more to get to a 1920x1080 output). I would avoid those for doing greenscreen work.

If it fits the budget find a full HD 3-chip imager camera with 4:2:2 video output will get you the best results. The EX1 was the first full HD 3-chip camera in its price range. Even my F3 can't match it in resolution.

From there going with a single Bayer imager camera with oversampled HD resolution and 4:2:2 output is the next step down.

Darren Levine May 22nd, 2013 11:40 AM

Re: Best inexpensive green screen camera
 
in an absolute price war, i don't see anything that can beat the BMC pocket, provided that it's all that they say it will be.

you don't NEED 10 bit to get clean keys, but it helps. you don't NEED 4:2:2, but it helps. what you absolutely do need is a camera that resolves good detail, so a lot of DSLRs won't be nearly as good simply because they only resolve 700ish lines.

again, the pocket will be $1000. jesus that's cheap considering what features it will have. even with a $700 ninja, there's no $300 camera to pair it with that will be as good.

you can of course spend more, the ex1 is great, but 4:2:0. then again, the hyperdeck shuttle 2 is only $350.

but for simplicity, the pocket will likely be king in this circumstance. that's why i preordered one. just in case i want it :)

Jon Fairhurst May 22nd, 2013 12:02 PM

Re: Best inexpensive green screen camera
 
Great input, everybody. It seems I haven't missed anything obvious.

Is the EX1 4:2:2 or 4:2:0? Maybe it's 4:2:2 through HD-SDI only? FWIW, the used prices I've seen are still out of budget.

External recorders can help, but only if the camera provides the resolution and depth over the wire. That's not always clear from the specs.

Regarding bit depth, that's not so much for pulling keys as for color matching the backgrounds. We'll try to match the lighting when we can, but the more latitude, the better.

The Pocket looks fantastic - in theory. We might just stick with the DSLR for now (and yes, they keys are soft and gloppy.) We haven't heard complaints about the keys. But come July, we will probably go with the Pocket to improve quality. At $1k, it's an easy decision.

I have to wonder if the original BMC prices will drop on the used market once the Pocket starts to ship? I'm not a resolution junkie, but for keys, color depth and accuracy are truly important.

When quality really, really matters, I'd bet the BMC 4K camera will be amazing. From what I hear, it might not be very light sensitive, but for green screen, that's not a big deal. Of course, you pay once for the camera and again and again for storage.

I'm still interested in hearing more about the XF100 for keying. It goes against the big-chip rage, but would be a nice tool when we need a more full-featured camera in the wild.

Chris Medico May 22nd, 2013 12:09 PM

Re: Best inexpensive green screen camera
 
I would recommend against any non-dedicated video camera for green screen work. No GH2 or 3. No Canon dSLR. No Sony NEX pocket cameras. If your definition of a "clean" key is flexible enough then they can work. No pro shooter will make any of the above cameras their first choice for greenscreen.

I would also recommend holding off on the BMC pocket camera until tests have been done to see if there are any issues with aliasing. Don't be the first person to jump on that train unless you like to take chances.

The EX1 is 4:2:0 internally and 4:2:2 output via SDI. Using an external recorder such as a Ninja or a Nanoflash is the key to getting the best results. I will say that using the internal 4:2:0 recording of the EX1 offers much better results than using a dSLR.

Chris Medico May 22nd, 2013 12:12 PM

Re: Best inexpensive green screen camera
 
Big chip cameras also have an additional disadvantage for greenscreen - DOF. Shallow DOF can look good when you are on a normal set but it can be a disaster on a green screen. Stop the lens down to F8 or F11 and any advantage in light sensitivity the large imager had is gone. If you are shooting with a Canon 7d an even softer image from diffraction at those iris settings starts to come into play.

A 1/2" or 2/3" conventional 3 chip video camera is hands down the best choice for greenscreen.

David Dixon May 22nd, 2013 09:03 PM

Re: Best inexpensive green screen camera
 
Jon, sent you an email with a link to an XF100 video that includes green screen. I can't post it here - includes minors.

I find the XF100/4:2:2/FCPX Keyer combination to be good quality and amazingly simple to use.

Steve Varnell May 23rd, 2013 08:19 AM

Re: Best inexpensive green screen camera
 
The Panasonic AG-AC90 will do a "great" job on green screen too. I wish I could share the video I took, but its for a short which has not been released. I just had to light the GS well (outdoors worked well) and I dialed down both of the detail settings to as low as they go. From what I see the video you can get with the AG-AC90 will work well IF you get a background that matches well too. When I keyed in FCPX the outdoor GS work I did FCPX keyed pretty much perfectly on all default settings. I did some tests indoors in my garage and although I had a 1k, 650w, and 2 300w Tungsten I needed a more "solid" light on the GS, so my tests results were just OK. I would have greatly preferred having Kino Flos for the GS, then I could have used all my Tungsten on my test subject (me).

Jon Fairhurst May 23rd, 2013 10:23 PM

Re: Best inexpensive green screen camera
 
@Chris - Good point on DOF. We use targets on the green screen for tracking and move the actors away from the screen to avoid green splash, so shallow DOF is definitely a hindrance. On the other hand, I haven't experienced a strong need for a true video camera. Our environment is very well controlled, so it's a set-and-forget affair on sticks. Audio is double system so about all we need is a lens, sensor, and storage - once things are setup. (For the 5D2, we used Magic Lantern's exposure tools for initial setup.)

The Pocket could be an excellent value. The sensor size is reasonable. The price is fantastic. From what I've seen, aliasing is minimal and the dynamic range is excellent. Rolling shutter is minimal, though this is not a big deal for small scale green screen work, but it's still nice. I think the risk is pretty low, given the low price and the likely ease of selling a used model in the early days.

@David - downloading the clip now...

@Steve - Thanks for the tip on the AG-AC90. The positives include the 3MOS sensor and the HDMI output. It records AVCHD (28 Mbps @ 60 fps, not sure about 24 fps), and that's likely to be 4:2:0. The sensor is 1/4.7". The XF-100 records 50 Mbps 4:2:2 MPEG-2 from a 1/3" sensor, so it wins on paper (other than the 3 sensors vs. 1). I would think that the AC90 needs an external HDMI recorder to really fly. Anybody know if the HDMI output is 4:2:2? How many bits? It's cheaper than the XF-100, so that leaves room for a recorder/interface.

The native XF-100 vs. the AC90 with external recorder would be quite the shootout!

Steve Varnell May 24th, 2013 10:04 PM

Re: Best inexpensive green screen camera
 
Yes it is 4,2,2 with an external recorder. I've not seen any footage with that way yet though.

Ron Little May 25th, 2013 07:28 AM

Re: Best inexpensive green screen camera
 
I have tried several cameras for green screen work and I always come back to my Sony V1 with a nanoFlash. It just gives me a really clean key.

Jon Fairhurst May 25th, 2013 11:51 AM

Re: Best inexpensive green screen camera
 
Interesting. The Panny AC90 is 3MOS, but only 1/4.7". The Sony V1 is 3MOS and 1/4". The Canon XF100 has a 1/3" sensor, but it's a single sensor Bayer. Pricewise, we step up from the AC90 to the XF100 to the V1. The XF100 is the only one that records 4:2:2 natively. The V1 and AC90 require external HDMI recorders, putting the AC90 solution and XF100 on par cost-wise and bumping the Sony solution past $3,000 (new).

A shootout would be golden. More information about what the AC90 and V1 put out on HDMI would be helpful too. (4:2:2? 8 or 10 bits?)

From the example that David sent, I see that all else being equal, noise indeed comes into the equation. We can pour on the light, but the cleanliness of the outputs at 0dB gain could make a big difference.


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