Black Magic PocketHD and 4K production camera

squig said:
"YOU WANT ANSWERS!"

Aliasing shouldn't be an issue pulling 4k off a 4k sensor, no lineskipping or binning. I imagine the pocket will alias just like its big brother..
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I want the people doing interviews to act a bit more like interviewers and less like the extension of a smoothie commercial guy's sales pitch.

Has a single person asked about an OLPF on the Pocket camera?
With all the experience we have had with this issue in the current model, why has no one bothered to ask this?
 
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Samuel H said:
It is not the same sensor of the Leica M. It is a different sensor designed by the same manufacturer. With completely different design goals, and therefore completely different characteristics. If it is the CMV12000, it is a sensor designed for high-speed machine vision, not for a motion picture camera. And it shows (even though, I must say it again, the sensor is pretty impressive in many ways; but not things like ISO or DR).
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I was watching one of the more recent videos, and they consistently call it a Super35mm sensor, not APS-C, which the CMV12000 is. It makes me doubt whether or not it is the CMV12000, although they may be doing that for obfuscation purposes.

Although, it could simply be a completely custom sensor from CMOSIS, or maybe even a custom sensor that used the CMV12000 as a template. We won't really know until someone gets one, and takes some close up pictures to compare it.
 
Luis Caffesse said:
Yes, we asked about the OLPF - we were told there is no OLPF on the Pocket cam or the 4K, and apparently no plans for one.
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Thanks you Luis for the clarity!

No way I am going for the Pocket camera then. Just imagine.
People should take a good hard look at their pre-orders before getting caught up in the hype.

The 4K thing is another story. Can anyone confirm that there will not be aliasing/moire issues because it is 4K as Squig mentions?
An OLPF is definitely not needed? Calling Barry Green!
 
With regards to the BMC2K; I read an interview with BMD recently that essentially said at the price points they are aiming at there is no OLPF - but that these can be added by 3rd parities for people that feel they need them and are willing to pay the added cost. Mosaic Engineering is said to be developing one for the BMC2K so presumably they will be able to make one for the 4K.

It seems highly unlikely that there will be a OLPF in the pocket camera at that price point. If demand is there for the Pocket camera then perhaps Mosaic, or some other company will make one. Given that the demand was high enough with the 5Dmk2 to make them, then there is a good chance that the BMC cameras will sell in similar number to make it worthwhile.
 
simonpwood said:
With regards to the BMC2K; I read an interview with BMD recently that essentially said at the price points they are aiming at there is no OLPF - but that these can be added by 3rd parities for people that feel they need them and are willing to pay the added cost. Mosaic Engineering is said to be developing one for the BMC2K so presumably they will be able to make one for the 4K.

It seems highly unlikely that there will be a OLPF in the pocket camera at that price point. If demand is there for the Pocket camera then perhaps Mosaic, or some other company will make one. Given that the demand was high enough with the 5Dmk2 to make them, then there is a good chance that the BMC cameras will sell in similar number to make it worthwhile.
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Mosaic does not answer queries about this. The BMCC OLPF question has been around for 3/4 of a year. Who knows when that issue will be dealt with.
Sorry, but it is too convenient for Blackmagic to pass it off on 3rd parties. I am surprised that they have not learned their lesson on this issue yet. It is major. No way for the pocket camera.
 
squig said:
"YOU WANT ANSWERS!"

Aliasing shouldn't be an issue pulling 4k off a 4k sensor, no lineskipping or binning. I imagine the pocket will alias just like its big brother.
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Except that their is also a compression scheme introduced the mix. Cineform compressed RAW. In addition the RAW is only 3840*2160, so it'll debayer down to about 3K.
 
yoclay said:
Thanks you Luis for the clarity!

No way I am going for the Pocket camera then. Just imagine.
People should take a good hard look at their pre-orders before getting caught up in the hype.
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I might be totally ignorant here, as I am more of a shooter than a gear head, but why would a 1080p sensor give moire on 1080p footage? As they don't have to downsample or skip lines. Where in the process are the aliasing introduced?
 
klas said:
I might be totally ignorant here, as I am more of a shooter than a gear head, but why would a 1080p sensor give moire on 1080p footage? As they don't have to downsample or skip lines. Where in the process are the aliasing introduced?
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Because it uses debayering
 
klas said:
I might be totally ignorant here, as I am more of a shooter than a gear head, but why would a 1080p sensor give moire on 1080p footage? As they don't have to downsample or skip lines. Where in the process are the aliasing introduced?
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The most common way to create aliasing (and moare) is the penetration of high frequencies to the AD converter, where the Nyquist rule is violated.
These high frequencies reflect the very fine details in the picture which are not currently filtered with the OLP filter. Once you create "false digital images" (aliasing and moare) after AD conversion then there is no way how them filter off (by reducing sharpness, etc).

http://www.youtube.com/watch?v=Fy9dJgGCWZI
 
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Or, in simpler terms, it's not even because of debayering: it is digital sampling that produces aliasing/moire.
This is the best explanation I've found yet: http://users.wfu.edu/matthews/misc/DigPhotog/alias/

The higher resolution of the BMC4K makes it less likely that you'll feed the sensor the frequencies that could create these issues (because they'll be finer frequencies and the lens destroys some of those - similarly to an OLPF but in a less controlled way, i.e. not tailor-made for your sensor).
 
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yoclay said:
Has anyone bothered to ask about an OLPF and potential moire and aliasing questions on either of these two cameras?

Honestly, sometimes I get so annoyed seeing the same fluff interviews over and over from 15 different sources.
Doesn't anyone ask a few hard questions?
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Also will the pocket cam movie uncompressed HDMImout without overlays? Then I can record directly to media with larger capacity than SD cards.
 
philiplipetz said:
Also will the pocket cam movie uncompressed HDMImout without overlays? Then I can record directly to media with larger capacity than SD cards.
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it will do both, with overlays and without.

You can connect the Blackmagic Pocket Cinema Camera to a huge range of equipment such as electronic viewfinders, monitors and disk recorders, using the camera’s built in HDMI output. The Micro HDMI output uses a small Type D connector and cables with Type D to full size Type A connectors are commonly available at low cost. The camera’s HDMI output includes an overlay setting with frame guides, f-stop, frame rate and more. The overlay can easily be disabled for a clean video output!
 
From the press release: The HDMI output includes all camera data such as timecode, transport control, shutter angle, color temperature setting and ASA information overlaid in attractive anti aliased fonts.

will it record without overlays, and at expected color depth and bit depth? JB's article indicated it could record with overlays but I the discussion thread he said he would have to check to see if the shipping unit was deliberately crippled so that overlays could not be turned off.
 
Again from the press release: Features all standard connections, including mini jack mic/line audio in, micro HDMI output for monitoring with camera status graphic overlay, headphone mini jack, LANC remote control and standard DC 12 power connection.


No mention of HDMI out without overlay.
 
Video over at that other popular video forum featuring Dan from BMD says 60p impossible with their current cameras without heat issues and looking not so good. Doubts a firmware upgrade would help and it may have to be a whole new much more expensive camera or sensor design.

I expected it was a heat issue. Regardless if you try to do lower resolution at 60p the speed of the readout at 60p may be too much. Not a big deal to me since I almost always shoot 24p anyway. Would have liked the option for 60p every now and then but considering everything else any of these cameras already gives us I can live with one compromise for now. If you need 4k at 60p there are plenty of alternatives out there.
 
Why does everything in this world have to be smaller, thinner, lighter, etc...

The pocket BMCC is awesome in terms of specs and price, but what kind of form factor is this? It is as big as my phone... It looks retarted and its hard to work with on a set. That's where this camera will be used right? On a set.

Or will this be a gadget to film your friends doing tequila shots with 13 stops DR?

If only camera manufacturers would build form factors that are actually pleasant to use as a camera, that would be great.
 
yoclay said:
Except that their is also a compression scheme introduced the mix. Cineform compressed RAW. In addition the RAW is only 3840*2160, so it'll debayer down to about 3K.
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Well, yes and no.

Here is a comparison at a 500% crop of an
Scarlet (with OLPF) at 4k
and a BMC at 2.5k

Both have moire (at other places though) and with the Wavelet compression and OLPF of the Scarlet,
it looks more soft and muddy, despite the fact it has a much higher resolution to start with.

Shoot.jpg
 
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