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GH2: MJPEG 100Mbps Low Light 1080p Settings
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  • johnnymjohnnym
    Is anything like this at all possible for the GH1? I have seen there have been improvements made to the MJPEG size patch for the GH2. Given the inferior quality of the GH1 upscaled VGA mode, can there be an improvement still?
  • HillTop1HillTop1
    Which anamorphic diopter is better? A +0.4 or +0.5 tokina?
  • LPowellLPowell
    @HillTop1
    According to one of the eBay vendors of these diopters, there is only one model of the Tokina +0.4 diopter, and the +0.5 is simply mislabeled.
  • RRRRRRRR
    @LPowell I wouldn't mind trying out 2:21 aspect ratio settings for the gh2, Maybe you can help in making the proper settings for it? (For 1.5x adapter) / tell me how to go about it. Is it possible to change pixel aspect ratio?
  • LPowellLPowell
    @RRRR
    For 1.5x anamorphic adapters, the correct MJPEG frame size in HD mode is 1920 pixels wide and 720 pixels high. These numbers should be used in the MJPEG 720p width and height settings in the latest version of PTool.
  • RRRRRRRR
    @LPowell
    OK! So there is no real benefit to use that particular format? (One might aswell squeeze down 1080 in post) Or am I not getting it? :)
  • LPowellLPowell
    @RRRR
    If you shoot in a 1920x720 frame size with a 1.5x anamorphic adapter, the 1920x720 videos will have the correct 1:1 pixel aspect ratio with no need to stretch the image in post.
  • RRRRRRRR
    @LPowell Ah! Penny drops.


  • driftwooddriftwood
    @LPowell Do you know what the frame size of the Panny G1:12 HFT012 3D lens is by any chance? I'm guessing its 16:9 Squeeze divide by 2?
  • LPowellLPowell
    @driftwood
    Panasonic seems to have avoided exposing any useful technical documentation on their 3D lens. It doesn't look like a pair of 2:1 anamorphic lenses, which would have been clever. What they have revealed is quite underwhelming - a pair of side-by-side 12.5mm f12 lenses that each produce a field of view equivalent to a 65mm lens on a full-frame still camera. That implies that each of the two lenses use about 40% of the width of the image sensor in 16:9 mode, and only 20% of the height. In my opinion, Panasonic has laid a pair of dodo bird eggs here...
  • driftwooddriftwood
    @LPowell Thanks for the info. Yeah I'm still dithering whether its a pile of dodo bird droppings or useable... On a nice bright day, it kinda works with the tape hack. It looks ok on a Viera tele, albeit squeezed incorrectly, so Im looking at rebuilding it in post - hence my question. Thanks once again for your detailed answer. Nick
  • alcomposeralcomposer
    @LPowell & @driftwood

    What would have been smart is doing what JVC were toying about for ages which is putting a small half silver mirror inside the lens at a 45º angle, but only covering one side- then bouncing the image to the other side with another 45º mirror with a variable offset. Considering the GH2 exposed sensor and m43 standard- there is LOADS of room inside the lens to construct a custom assembly. This way you could use any Nikon / Canon lens (because it needs the room) with a 3D adaptor...

    Just an idea- YMMV. This idea would have to be SUPER refined to work. In fact I can already think of issues,.. but it would be 3D!

    Besides I have sworn off 3D until the tech gets better in my opinion. (what does that mean?)
    Well having 2 cameras Genlocked and Synced is just problem No1. Then you got dynamic positioning of the offset - toe in etc... 2x Scarlet- what 40 grand (with everything) but the Rig will put you back a house! Darn!
  • driftwooddriftwood
    @alcomposer yep, there's no simple solution/cheap option, but I'm sure we're going to get a few lens manufacturers attempting summit. Syncing 2 gh2s with identical lenses is not for the faint-hearted.
  • alcomposeralcomposer
    Forget about syncing - I know of stories where (and VK has posted this recently) regarding 2 lenses that just didn't sync due to construction. The focus was out- the barrels everything.

    So its not just Hightech sync - its also low tech as well, (well not low tech -but you get the idea)! And with 3D you have to get EVERYTHING in... or pay a mastering house heaps of cash- whatever you prefer... they can even convert now- and its getting cheaper!
  • driftwooddriftwood
    @LPowell I sort of dont wanna be beaten by this bleedin panny 3D lens until I can at least get a decent workflow going and it seems like your mjpeg stuff could make summit happen. So, lets see if anyone can help.
    If you record in AVC 1080p24 you have two split images contained in 1920 x 1080 and squeezed as shown in image. So this is two 960 x 1080 pictures for Left and Right.
    The problem is you cant just stick it into a Viera 3D TV cus the resultant image is squashed, its like widescreen acting on widescreen. You cant correct aspect ratio on a 3D image with these TVs.

    So I need to rip out each side in an editor OR record in a correct aspect ratio which could mean squeezing even more out of the picture using mjpeg so that will 16:9 or whatever best scales to the TV. What would you suggest? Im wondering if 1440 x 540 might crack it.
    3d Sequence 02-1.png
    1440 x 1080 - 2M
  • alcomposeralcomposer
    Lots of macro-blocking on the chairs... what settings did you use to record the dinner?
  • driftwooddriftwood
    Forget the piccie quality - its spanmybitchup hi iso, testing out in a v dark cafe - for the record - just trying to check frame sizes.
  • truestorytruestory
    *** 100mbps PAL*** Just came across this Post and read opening statement on the patch..L Powell says this patch is NTSC & PAL...I am GH13 X 8 user and yet to get the GH2 as I thought the PAL side was a dead duck...
    Can I get this 100mbps MJPEG patch @ 720P25, 720P50 or 1080P25 or am I still sobbing in the dark...

    Many thanks

    Truestory
  • alcomposeralcomposer
    @driftwood sorry to be a pain about the quality of the image- but considering how dar it would have been- and the fact that this lens is a Daylight lens --- GOOD JOB!
  • driftwooddriftwood
    @LPowell Been reading here, Why don't you let the encoder choose the Quant tables? If the Quality is high enough...
  • LPowellLPowell
    @driftwood
    Not sure what you mean, the MJPEG encoder has four patchable sets of Tables and Quantization factors that determine how it encodes each macroblock. Table 4 produces the highest detail and I suspect its elements are all set to one, or something very close to that. Tables 0-3 are dysfunctional and produce blank macroblocks. The first attempts at high bitrate patches on the GH1 used nothing but table 4, and as you might imagine, this type of brute force approach produces very inefficient MJPEG encoding that wastes bandwidth and emphasizes edge artifacts.
  • driftwooddriftwood
    @LPowell Did you mention in the past that E1/F1 was chrominance and E4/F4 was luminance?
  • LPowellLPowell
    @driftwood
    Nope, wasn't me. My hunch is the chroma tables are hard wired with the luma tables.
  • driftwooddriftwood
    Definite effect on chrominance on E1/F1.
  • fatpigfatpig
    on the 3d lens...
    I have it, and its 2 pictures in about 3:4 aspect, which already have the correct aspect ratio, which is horrible and unusable for movies. and to make matters worse: the dividing "line" is not in the center, but some 40 pixels off.. its really sad.

    maybe with an anamorphic adapter that is really wide one could at least get 16:9?
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