1. Reminder: Please use our affiliate links for holiday shopping!

Exposure/Histogram puzzle with GF1

Discussion in 'Panasonic Cameras' started by Rider, Mar 28, 2011.

  1. Rider

    Rider Mu-43 Regular

    139
    Oct 14, 2010
    No matter what ISO/shutter/f-stop combination I choose in fully manual mode, the GF1 histogram shows me a perfect exposure. It looks like the histogram shows what's going on the screen, rather than the picture to be taken, and the screen adjusts to light conditions making the histogram USELESS.

    Please tell me there is a way to fix this.
     
  2. ~tc~

    ~tc~ Mu-43 Hall of Famer

    Oct 22, 2010
    Houston, TX
    Is this while you are framing the picture, or after you press the shutter?

    Because I think the only "accurate" histogram on these cameras is on the exposed JPG image. There have been many discussions about applying some "windage" to the histogram when shooting RAW.

    That said, unless you have a really extreme situation, I don't see why you would use full M mode for an unmetered scene. P mode with program shift and exposure compensation is a helluva lot more efficient IMHO, or meter in A or S mode, then flip to M mode to make those settings constant (ie for stitching a panorama).
     
  3. Rider

    Rider Mu-43 Regular

    139
    Oct 14, 2010
    This is while taking a picture. We're not talking about an "inaccuracy". We're talking 100% wrong. The screen COMPLETELY compensates for any adjustments you dial in, so whatever you dial in looks like a perfect exposure on the live histogram. Try it, and let me know if I'm fibbing. With photos, it's annoying and unprofessional. With video, this is a total disaster.
     
  4. Howi

    Howi Mu-43 Veteran

    208
    Feb 23, 2011
    Sheffield
    Howard
    I wondered about this too, seems the live histogram is showing (what the camera thinks) the histogram is, based on the metering information in camera, without any adjustment based on chosen settings.
    I would imagine the only way of seeing the 'actual' histogram in this case, is after the shot on the preview.
    As you say, a bit of a bummer when trying to expose to the right.
    Perhaps this is something Panasonic could do with looking at.........
     
  5. mauve

    mauve Mu-43 Top Veteran

    892
    Mar 9, 2010
    Paris, France
    Mandatory reading (all cameras) :

    Settings for an Accurate Histogram

    Although I don't own a Panasonic and only played briefly with my brother's one, I bet you might need to turn film setting to 'standard' instead of dynamic and i.Exposure to off to get a somewhat more accurate histogram. Lowering contrast to minimum is an absolute necessity.

    Cheers,
     
    • Like Like x 2
  6. thanks mauve. Sort of guessed that RAW image was primarily effected by ISO, A & S. Was clueless regarding ETR.
     
  7. Rider

    Rider Mu-43 Regular

    139
    Oct 14, 2010
    Everything is on manual. The histogram is not just slightly off. What I am saying is that changing exposure settings has ABSOLUTELY NO EFFECT on the live histogram. It doesn't move a single iota.
     
  8. mauve

    mauve Mu-43 Top Veteran

    892
    Mar 9, 2010
    Paris, France
    Difficult guess as I don't have your camera, but is your LCD mode set to Auto brightness per chance ? In that case try to turn that off, you should see your exposure tweaks now.

    Just my 2 cents.

    Cheers,
     
  9. flaxseedoil1000

    flaxseedoil1000 Mu-43 Regular

    102
    Mar 10, 2011
    Not the LCD mode because this happens in the EVF too.

    Don't feel bad, it's not very intuitive and the manual is no help.

    Try this:

    Manual mode, aim at some shade, like under a tree, F16, set the speed to get correct exposure - histogram will be white

    Now increase the speed to 1/4000 - histogram won't 'move' but it will change to orange

    Take the shot. The 1 second preview looks great. Now 'play', the shot you just took is actually pitch black or close to it

    Same test with a zoom lens

    Manual mode, aim at some shade, like under a tree, zoom in, F16, set the speed to get correct exposure - histogram will be white

    Now zoom out, histogram will 'move' and change color to orange

    For me, in manual mode, racking the zoom in and out will move the histogram while changing the exposure will not. Each will change the histograms color.

    Same results?
     
  10. ~tc~

    ~tc~ Mu-43 Hall of Famer

    Oct 22, 2010
    Houston, TX
    It is well known that the live view lies, always gaining up and often showing a brighter image than what will be captured.

    It is also well known that pressing the DOF/trash button then the DISPLAY button will change the Live view to WYSIWYG for that shot.

    It is also well known that the histogram shown in playback mode is accurate for the JPG.

    So, the recommendations are simple:
    - use the wysiwyg button sequence
    - fire off test shots - this IS digital, not film, after all
    - if neither of those will work for you, you need to buy a different camera
     
    • Like Like x 2
  11. Howi

    Howi Mu-43 Veteran

    208
    Feb 23, 2011
    Sheffield
    Howard
    Just been doing some tests, in manual mode histogram will show white when exposure is correct and will change to orange when exposure is changed + or -, histogram will not differ.
    go to A or S mode click the wheel to highlight the histogram (orange ) rotate the wheel to increase or decrease the exposure compensation and histogram will change to reflect the exposure, allowing you to expose to the right if you wish.
    i can only assume that in manual mode it assumes you are making your own decisions so don't need histogram.
    If A or S mode will do the trick, why do you need full manual mode?
     
  12. Rider

    Rider Mu-43 Regular

    139
    Oct 14, 2010
    Thanks for all you replies.
     
  13. DesertRose

    DesertRose Mu-43 Regular

    91
    Dec 1, 2010
    Colorado
    I did not know the WYSIWYG sequence, thanks for posting it. :thumbup:

     
  14. Rider: Howel has it right. I discovered what you are seeing a month ago and put a post up about it, though I can't find it now. When you are in the full manual mode your options are aperature-via the lens, ISO via the dial-buttons, zoom via the thumb wheel and exposure/shutter via the alternate thumbwheel mode. This will adjust the EV +/-. When it is neutral and turns white (or orange, may be backwards here, I don't have my camera iwth me right now to check) you have the exposure correct. Note, this was with a thrid party lens that has manual f-stops.

    With a Panasonic automatic lens I would assume that the thumb wheel give you aperature and shutter speed modes, not the zoom feature, but you still need to watch the EV value to get the exposure right. It's sort of like using an old match-needle camera if you are familiar with those.

    The histogram, as you note, does not seem effected.
     
  15. OK, I found the post buried in the thrread: https://www.mu-43.com/f43/gh2-sampler-thread-9983/index4.html

    I learned a good lesson relative to use of the GH2. Initially I was shooting in aperature priority, but I was having trouble with gettng the thumb dial to dial in an extra 1.5 EVs that I needed to get the histogram up. Couldn't figure it out because in no-lense mode, one click is used for the focus enlargement and the other is for exposure level, but it is a bit tricky until you get some experience with it. I think I may have been in S mode by accident. It works like this:

    P mode: focus enlargement / EV +/-
    A mode: focus enlargement / EV +/- (use with non auto lenses)
    S mode: focus enlargement / shutter speed
    M mode: focus enlargement / shutter speed

    What's confusing here is that if you are thinking, 'How do I change the EV in S and M modes then?' The answer is that you don't, at least not by using the EV adjustment. You change the shutter speed and or the f-stop on the lens and the EV will begin to read + or - according to how much light you've dialed in. Essentially is becomes a match needle meter, like in the old days, but it's better - it tells you exactly how many EVs, in thirds, you are off the correct meter setting.

    Sitting in the house and thinking about it, it seems obvious and simple. But standing the drizzle and puzzling out how to get an extra 1.5EV was confusing me. This is not a simple camera and it is going to take some practice to fully understand its workings.


    I'm 95% certain, without trying it with the camera, that with a Panasonic lens the thumb wheel gives you:

    M mode: aperature value / shutter speed

    Then just watch for your EV scale to center.