Personal View site logo
GH2 and 4K fantasies
  • This discussion was created from comments split from: Official GH2 "Stalin" hack development topic.
  • 17 Replies sorted by
  • Time to start hacking a GH-3 for 4k recording. Whould we call it Gorbachev?:-)

    "With Sony’s A77 set to feature a 3MP OLED EVF, Panasonic are concentrating on refresh rate and resolution. To drive the faster refresh rate and a 3MP EVF, the camera will need to produce a live video feed of at least 2048 x 1536 (4:3) or 2208 x 1248 (2.8MP in 16:9) at 60fps to the viewfinder. Possibly even as high as 120fps to match the refresh rate of the panel. Modern LCDs usually refresh at 120hz (like TVs and their anti-cinematic ‘smoothing’ modes).

    That leads the door open for higher than 1080p recording capabilities or at the very least 1080/60p. The GH2′s sensor already outputs this but the image processor interlaces it. If the sensor and image processor in the GH3 is fast enough to power the new EVF, it would certainly in theory be capable of 4K in 24p mode as well, although it is doubtful Panasonic will move to 4K before the standard becomes more common in consumer displays devices like TVs."

  • I know :-)
    http://www.eoshd.com/content/3061/gh3-to-have-emphasis-on-low-light-performance-new-evf-technologies

    Proper approach to Andrew site is to look at it as mix of fantastic drama and comedy :-)
    Sometimes it is interesting, sometimes just personal fantasy.

    But never ever use this info as foundation of your real expectations.
    Same for all rumors sites.
  • Comedy - well, we Brits try our best to have a sense of humour ;-)

    My imaginative / speculative bits don't always come across to people who's English is not native, which is understandable.

    Here in this case referring to article linked above, the facts are:

    - Panasonic are looking at a higher resolution EVF with Epson, their supplier.
    - A 3MP LCD panel is 2048 x 1536 in 4:3 ratio but exact resolution will depend what aspect ratio they choose. Probably 3:2 in the Sony A77.
    - Modern LCDs are capable of 120fps refresh rates - TVs, etc.
    - GH2's sensor is capable of 1080/60p (but LSI encoder interlaces the output, throws away half the fields per frame - is that for compatibility or processing power reasons? Probably a bit of both. Vitaliy might soon find out for sure.)

    The rumours in the article (though good quality, from SonyAlphaRumor's best sources and grading level) are:

    - A77 will have a 3MP EVF

    The logically deduced stuff is:

    - Panasonic will attempt to match or beat Sony's A77 3MP EVF specs with the GH3
    - If CMOS sensor and electronics can perform 3MP at 120fps for an EVF, it will have data processing capacity to do 4K (roughly 8MP) at 24p, since it is similar amount of data. More lines, but less per second.

    There is a bit of speculation too:

    - EVF "probably as high as 120fps refresh rate". We don't know exactly what Panasonic mean by increased refresh rates of the EVF. It could be 60fps. It could be 240fps. We just don't know yet, and maybe Epson haven't decided what to build as part of the deal yet.

    Hopefully this explanation will help people follow my logic in a clearer way. Don't be too hard on news & rumours Vitaliy - how many times has 43rumors.com been right about upcoming product specs before they are officially announced? Many times - sometimes months in advance!!
  • @EOSHD
    My favorite English text is from 1939: Nobody wants to die for Danzig. Until today, nobody in my country can not understand it. :-)
  • >Panasonic are looking at a higher resolution EVF with Epson, their supplier.

    This one cames from interview. Yes, they are looking for higher res EVF.
    Looking do not mean that they'll be using it in next generation bodies.

    >A 3MP LCD panel is 2048 x 1536 in 4:3 ratio but exact resolution will depend what aspect ratio they choose

    They never used color LCD panels for EVFs. As they use special color sequental Epson EVFs.
    So, famous 3Mp Sony panel could be really 1Mp panel with each color pixel counted :-)
    Panasonic do it in their EVFs already even not having actual pixels :-)

    >Modern LCDs are capable of 120fps refresh rates - TVs, etc.

    And? Modern glass is able to break if you throw it in the wall. Same relation :-)

    Current EVF is sequental. So, if you are talking about 120 true fps, it means 360 color switchings per second.
    Even 120fps LCD TVs have artefacts, 360fps is just not possible.

    >GH2's sensor is capable of 1080/60p

    Are you sure about this?
    I have big doubts.

    >The rumours in the article (though good quality, from SonyAlphaRumor's best sources and grading level) are:
    >A77 will have a 3MP EVF

    Fuck this best sources.
    They had been wrong or partially wrong about 90% of the time.
    After few private talks recently my opinion about rumors and their nature dropped right into the floor.

    As for deduction - it is pure and plain fantasy.

    >We don't know exactly what Panasonic mean by increased refresh rates of the EVF.

    As I said, it is easy. Higher sequental color switching allows to reduce famous rainbow.

  • The official GH2 spec sheet and back of the manual says the sensor output is 50p/60p for the 1080i mode. So it comes off the sensor progressive and is only then interlaced by the LSI for HDMI output and AVCHD encoding. Also it follows that to achieve the faster contrast detect AF system of 120 cycles per second, they needed to increase the speed of the sensor. Rolling shutter is less severe in 1080i mode than in 24p, because of the faster rolling shutter scan of the sensor. I suppose like you do that they could do an interlaced scan on the sensor itself and achieve the same results, but that wouldn't help contrast detect AF and it doesn't explain why Panasonic give the sensor output spec as 60p in the manual.

    As you know Vitaliy the AF100 shares a similar (but not identical) sensor, and that does 1080/60p as well. There the AVCHD encoder stores it as slow-mo 24p.

    Deduction isn't fantasy - Dragons, myths and Harry Potter are fantasy. Deduction is knowledge based and scientific, it's possible to do it with a camera market, a technology, all kinds of things.

    Sure we don't know 100% until the official announcement from Panasonic HQ - but you have to look ahead of where the ball is going. One of the reasons Steve Jobs runs Apple so successfully is that he decides the direction of the market by deduction, and figures out the future before anyone else. You could call that fantasy, imagination - but then it is applied to the market and it turns out to be right.

    Maybe neither of us are right... maybe we are both right... maybe you are right and I'm wrong... but there's enough room in a world of 6 billion for different philosophies and approaches to one's perspective on life, and each person has more than one! I actually share some with you. It is just we differ on the whole 'speculation' stuff, as I did with the DVXUser team.
  • What a perfect example of Comedy and high Drama!
  • @eoshd whatever...
  • Andrew, just read my previous post carefully. :-)

    Is sensor capable of 60p - I don't know for sure, but have doubts.
    At least I have foundation - I looking at init code.
    Panasonic sensors is not that you think they are, they are not so dumb, can do some things themselves and you can find how body is initializing this things.
    And while I am sure that even GH1 is running sensor at 60p at some modes, it does not mean that it can do true 1080p. Same thing can be true for AF100 that have especially low measured resolution.
    This string that you are referring to can mean anything, really.

    >Maybe neither of us are right... maybe we are both right... maybe you are right and I'm wrong...

    You are terrible in disputes, this one I remember :-)

    Remember - use KISS principle in life. Do not start fantasy about 4K if all the facts have simple explanation albeit not so attractive
  • Cant see the point in 4k myself...None of my stuff would be going on the cinema...I think too many DSLR users are under this dillusion.
    Im sure 4k tv's will be around the corner but unless theyre HUGE youre not really going to benefit from the increased resolution.

    Going a little off topic here.
    As for GH3...Heres my somewhat cynical prediction...it will be pretty much the same as a GH2 only with a few minor tweaks and gimmicks to convince the consumer to sell on their GH2 for. (GH1,GH1.1=GH2,GH2.1=GH3...so on)
    Camera companies lately are lacking in making huge technological advances...maybe due to financial situations and try to "play safe"...Panasonic are very guilty of this.

    90% of what can be read on forums and rumour sites is "wish lists" but generally most of the wishlists are not fulfilled..but everone goes and buys the new product anyway ...I bet many will still buy the GF3 for example even though it doesnt really offer anything new.
    Answer with your wallet and maybe the companies may deliver something new...
    Anyhoooo
  • @mimirsan
    I don't get the desire for 4k either. Even if you want cinema release, afaik they don't scan let alone project at anything but 2k. Give me more latitude, a cleaner image, eliminate banding, blocking, less noise, but 4k? who needs it!
  • yes, sorting out exisitng problems (banding, noise etc.) is the most important, but having 4k plates would give you a lot of reframing options, right?:)
  • Yes to more latitude, higher bitrate, 10 bit encoding for better gradient, these are more important for now than pure resolution. The gh2 and now the hacked gh2 resolution is very high. I would prefer some smooth gradient in the sky that any more resolution.
  • 4k in a bayer pattern? Why is this better than 1920 with pixel binning from a 16MP sensor?

    I am the first to suggest the most crazy ideas.. however- what would this give us that we don't have anyway? There is just NO way that this camera can do RAW 4k (VK if it can- you will get sooooooo many donations! read: retire to tropical island). Raw is the only way you would want to use 4k - while pixel binning gives you 1920 x 1080 'super' pixels- which act like a RGB sensor - sampling the light with all of the colours...
    It is for this reason and this reason only that RED and everyone else is going for larger sensors- (4k-5k-8k- in a single chip config) because in the end you are binning everything down to a c. 2k image anyway, and you need all of that colour info. (that and RED wants to make a sensor so large that the lenses don't even exist yet- except if your nasa... )

    This is not to say that I don't believe I will use 8k or greater- its just that now in 2011- the GH2 represents an amazing piece of gear, +Large sensor+ Pixel Binning + low light = priceless!
  • @acomposer - the thought of the GH2 doing 4k is a bit of a long shot and I dont think its possible. The sensor would just over heat and pop.

  • whats the possibility of changing the aspect ratio of the ETC mode with the hack? could that allow higher resolutions?
  • I remember from news before the gh2, Panasonic talked about Gh2 sampling sensor at 60p then downsampling to full (I think it was not bayer pattern either). But if it is doing this in sensor before outputing full, then it should nite be possible to get 4k. That is why I was shocked when Vitaliy originally said it was not possible.

    The only way to know is to really hack the camera deep to find if it is there. But then again, wait 2 weeks and you might see multiple 4k Panasonic cameras.

    So maybe a better use if line to hack Samsung note 3 for better faster 4k recording (does p30).