Low light performance of prosumer camcorders at +6db compared to 5D Mk. II

Discussion in 'Digital Video' started by Chris7, Nov 7, 2009.

  1. Chris7 macrumors 6502

    Joined:
    Aug 8, 2008
    Location:
    Lost in Thought
    #1
    Hello,

    I have an acquaintance who has both a Panasonic HMC150 and a Canon 5D Mk. II. He said that the Panasonic with +6db (one stop) of gain looks noisier (more grain) than the Canon at ISO 6400. I believe the HMC150's has a sensor with a native ISO of 400, and from what I can tell, the 5D Mk. II shows almost no grain at ISO 1600. So I was surprised that simply adding an extra stop of gain to the Panasonic (basically ISO 800) would add more noise than the Canon at ISO 6400 or even 3200. I thought the Panasonic would fair better than this and was quite surprised, but I do not know this photographer well enough to ask for a file of comparison shots.

    I am curious if anyone here has done low light comparison of the video of the 5D Mk. II vs. some of the camcorders that are said to have particularly good low light performance (I have heard that the HMC150, HPX170, and Sony PMWEX3 all have sensors with native ISO 400, for example).

    I’m wanting to know what these cameras look like with 6db of gain, compared to the video of a 5D Mk. II. Does the camcorder have similar noise/grain at +6db to the 5D Mk. II at ISO 3200, 6400, 1280?

    I realize they all use different codecs, which may play into this somewhat, but it would seem there would still be a way to make a general comparison of the noise/grain at +6db vs. the Canon at various ISO.

    (I’m not buying until I see what the RED Scarlet 2/3” Fixed does to the rest of the prosumer market, so the question is a bit theoretical for me. But I hope the question is also of general interest to some of the people here.)
     
  2. jared_kipe macrumors 68030

    jared_kipe

    Joined:
    Dec 8, 2003
    Location:
    Seattle
    #2
    What I have found out from googling that camera is that it uses 3 1/3-inch CCDs. Assuming that thats .33 inch diagonal measurement, and assuming the same aspect ratio, then the 5DmkII's sensor is 4.2 times the diagonal measurement. (16 times the area!!)

    I would expect that to mean lower noise at higher ISO.

    EDIT: Assuming the .33 inches is its smallest measurement (the height) then the 5DmkII's sensor is about 1.6x just that dimension. Making it 2.56x the area.
     
  3. Chris7 thread starter macrumors 6502

    Joined:
    Aug 8, 2008
    Location:
    Lost in Thought
    #3
    clarifying

    As far as I can tell, the 5D Mk. II has surperior low light performance to the prosumer Panasonic and Sony by about two stops. Please correct me if I'm wrong, but seems that the 5D Mk. II at ISO 1600 looks similar to the Panasonic's and Sony's without gain (native sensors are about ISO 400).

    But once you add just 6db of gain (one stop) to the Panasonic, you apparently do not get an image with similar noise/grain as the 5D Mk. II with an extra stop (ISO 3200). As the photographer mentioned above said, his HMC150 with +6db of gain looks nosier/grainer than his 5D Mk. II at 6400 (an extra two stops).

    If he is correct, its looking like the 5D Mk. II actually gives three stops greater low light performance than the prosumer Panasonic with +6db of gain.

    Just posting to see to confirm if this congruent with the experiences of the people here.

    Thanks,
    Chris
     
  4. jared_kipe macrumors 68030

    jared_kipe

    Joined:
    Dec 8, 2003
    Location:
    Seattle
    #4
    Noise is usually not linear, but exponential.

    Check out the noise graphs http://www.dpreview.com/reviews/canoneos5dmarkii/page21.asp

    If the sensor is already noisier at lower ISO's then adding gain on it is going to make it exponentially noisier.
    The size of the sensor does matter, bigger sensors will generally have better noise-to-ISO ability no matter what ISO you go to.

    However, when someone is talking about having 2 stops better noise or something, they are comparing it to some kind of set ISO. For example, when saying that the 5DmkII video @1600 looks similar to the video from another camera @400, that is a two stop advantage. You would EXPECT that advantage to get bigger when going to higher ISO's because of the exponential nature of noise.
     

Share This Page