Snapper123
Well-known member
Hey guys, I got a theory on histogram exposure. Alrighty, I know that histograms have four lines, but let's pretend they have three: one directly in the center for 50% grey, one near the right for 25% grey, and another near the left for 75% grey, with each side of the histogram being 100% black and 100% white. So next, how you'd find exposure would be to take a full frame picture of a three part card - one part of the card 100% black, one part of it 50% grey, and one part of it 100% white. The simple way to know that that card is exposed 100% properly is to have each spike in the histogram, which should be extremely thin and high, spiking up at their specific lines, representing that your card's three colors are exactly to the pin exposed in line with both color and light properties. But since most scenes will usually have a place that's naturally too overexposed, like a window, or a place that's darker than the black on the card, the ideal would seem to be to shoot flat enough where the camera reads the card as this; black is 75% grey, 50% grey is still 50%, and white is now 25% grey on the card. That would leave you a good 25% of latitude and information on both the dark side and light side of your scene to back you up - I'm guessing that this is how film naturally works, as DSLR's seem just way too sensitive to changes in light. But that is where shooting flat on these cameras may help save the day a bit!
So am I correct? Just for the explaination, I pretended as though a histogram only has three lines, each representing an exact 1/3 percentage of light, but it seems the exact scenario would be applied anyway, even if the histogram had only 2 lines or 10. But anyway, yeah, I made all this up, I'm really frustrated with Youtube guides that say "Oh just look at your picture and if you have a lot of whites, then of coarse they're gonna be all clumped to one side, means it's correct!" - that is NOT how a histogram is supposed to help you decide a correct exposure based on a three-part card system, in my opinion. As it makes no sense. But I may be wrong. I just believe that finding the most absolutely perfect exposure for a well lit scene involves making sure your whites, blacks, and greys are equally apart from each other in the histogram, that none of them go past the 100% point on either side, and that you're shooting flat enough to give you a little bit of room on both ends. Now, I don't even have a three-part card on me to check this theory, but it sounds nice in my opinion!
P.S. I just tested this theory using a grey card, a white card, and a black card (instead of the quick way of using a three-part card), and this test seemed to give me the perfect exposure, in which the camera said everything was 2/3 overexposed but then I panned around the room and used the viewfinder with evaluative mode to check if the exposure test was right, as the viewfinder exposure modes are more accurate, and it seemed to be perfectly correct! I also shot completely flat, in which if my cards are the right tones, caused the white to spike up at 25%, and the black to spike up at 75%, which means that I have 25% of latitude on each side of the histogram to wack off with!
P.S.S. I have no clue why this is in lens discussion, please move it to any section ya'll want, I sure didn't mean to post it here.
So am I correct? Just for the explaination, I pretended as though a histogram only has three lines, each representing an exact 1/3 percentage of light, but it seems the exact scenario would be applied anyway, even if the histogram had only 2 lines or 10. But anyway, yeah, I made all this up, I'm really frustrated with Youtube guides that say "Oh just look at your picture and if you have a lot of whites, then of coarse they're gonna be all clumped to one side, means it's correct!" - that is NOT how a histogram is supposed to help you decide a correct exposure based on a three-part card system, in my opinion. As it makes no sense. But I may be wrong. I just believe that finding the most absolutely perfect exposure for a well lit scene involves making sure your whites, blacks, and greys are equally apart from each other in the histogram, that none of them go past the 100% point on either side, and that you're shooting flat enough to give you a little bit of room on both ends. Now, I don't even have a three-part card on me to check this theory, but it sounds nice in my opinion!
P.S. I just tested this theory using a grey card, a white card, and a black card (instead of the quick way of using a three-part card), and this test seemed to give me the perfect exposure, in which the camera said everything was 2/3 overexposed but then I panned around the room and used the viewfinder with evaluative mode to check if the exposure test was right, as the viewfinder exposure modes are more accurate, and it seemed to be perfectly correct! I also shot completely flat, in which if my cards are the right tones, caused the white to spike up at 25%, and the black to spike up at 75%, which means that I have 25% of latitude on each side of the histogram to wack off with!
P.S.S. I have no clue why this is in lens discussion, please move it to any section ya'll want, I sure didn't mean to post it here.
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