Day 56 - Photo A Day Challenge - 2-25-2012
Feb 25, 2012 02:43:33 #
Welcome to Day 56 :) Take a deep breath .. get a cup of coffee ... and sit back and relax before reading today's challenge. Today we are going to attempt Understanding the Histogram. Now before you start hyperventilating ... give me a few minutes to explain.
One thing I want to make very very clear. The histogram is NOT the be-all end-all magic answer for exposure problems. It is more of a generalized guide.
Ok so I want to explain how the camera works as far as exposure goes. Picture in your mind 3 paint cans .. all lined up in a row .... and your camera is the painter. The can on the left is full of black paint. The can in the middle is empty. The can on the right is full of white paint.
Now here is the dilema. The painter (your camera) wants to paint everything in a nice medium grey color. Not too dark, not too light. So the painter looks at the big job ahead of him and decides he can make the color he wants by mixing the black paint with the white paint to get just the perfect shade of grey. Should be simple to do right?
So he starts mixing in the empty can ... when the final result ends up being dark grey ... he looks at it and decides he needs to add more white paint ... to get it to be medium grey. If it ends up being light grey .. he decides he needs to add more black paint to bring it back to medium grey.
So that is what happens .. the camera takes all the colors in the scene you are trying to photograph ... mixes them all together ... and tries very hard to end up with medium grey for a color. (figuratively speaking .. not literally)
If your scene is what the camera perceives as too dark it lets more light in.
If the scene is what the camera perceives as too light it lets in less light.
This is why when you shoot in program mode (P) you will notice the settings change all by themselves. It's the painter (your camera) attempting to make medium grey.
When you adjust the exposure compensation .. you are essentially telling the camera ....(the painter) to go ahead and make the color he wants .. but then add this much extra white or this much extra black because that's the color you like ... and he works for you so he should do as you say.
If you are going to look at the histogram to help you adjust the exposure the MOST important thing is that the color does not go off the edge of the display. It can be as ugly or spikey as it wants to as long as the color falls somewhere in between the 0 on the black side and the 255 on the white side.
Here are a couple visual aids to help you understand what you are looking at.
One thing I want to make very very clear. The histogram is NOT the be-all end-all magic answer for exposure problems. It is more of a generalized guide.
Ok so I want to explain how the camera works as far as exposure goes. Picture in your mind 3 paint cans .. all lined up in a row .... and your camera is the painter. The can on the left is full of black paint. The can in the middle is empty. The can on the right is full of white paint.
Now here is the dilema. The painter (your camera) wants to paint everything in a nice medium grey color. Not too dark, not too light. So the painter looks at the big job ahead of him and decides he can make the color he wants by mixing the black paint with the white paint to get just the perfect shade of grey. Should be simple to do right?
So he starts mixing in the empty can ... when the final result ends up being dark grey ... he looks at it and decides he needs to add more white paint ... to get it to be medium grey. If it ends up being light grey .. he decides he needs to add more black paint to bring it back to medium grey.
So that is what happens .. the camera takes all the colors in the scene you are trying to photograph ... mixes them all together ... and tries very hard to end up with medium grey for a color. (figuratively speaking .. not literally)
If your scene is what the camera perceives as too dark it lets more light in.
If the scene is what the camera perceives as too light it lets in less light.
This is why when you shoot in program mode (P) you will notice the settings change all by themselves. It's the painter (your camera) attempting to make medium grey.
When you adjust the exposure compensation .. you are essentially telling the camera ....(the painter) to go ahead and make the color he wants .. but then add this much extra white or this much extra black because that's the color you like ... and he works for you so he should do as you say.
If you are going to look at the histogram to help you adjust the exposure the MOST important thing is that the color does not go off the edge of the display. It can be as ugly or spikey as it wants to as long as the color falls somewhere in between the 0 on the black side and the 255 on the white side.
Here are a couple visual aids to help you understand what you are looking at.
Too dark
Too light
Just right
they don't have to be perfect or even pretty as long as you know what it is you are looking at .. click the download button to see it larger
Feb 25, 2012 02:47:41 #
So with this in mind .. our challenge for today being Saturday and a lot of you will be off work ...
Go out and photograph anything ... check the histogram on the screen after each photo .. and adjust if you need to.
Doesn't matter what you photograph .. the important thing is to Understand the Histogram. :) I look forward to your feedback
Go out and photograph anything ... check the histogram on the screen after each photo .. and adjust if you need to.
Doesn't matter what you photograph .. the important thing is to Understand the Histogram. :) I look forward to your feedback
Feb 25, 2012 03:47:37 #
Good morning, everyone. :D
Sherrie, this one wanted you and everyone else on UHH to know that he has "lady" friends too :-D
Sherrie, this one wanted you and everyone else on UHH to know that he has "lady" friends too :-D
Feb 25, 2012 04:03:37 #
photogrl57 wrote:
So with this in mind .. our challenge for today being Saturday and a lot of you will be off work ...
Go out and photograph anything ... check the histogram on the screen after each photo .. and adjust if you need to.
Doesn't matter what you photograph .. the important thing is to Understand the Histogram. :) I look forward to your feedback
Go out and photograph anything ... check the histogram on the screen after each photo .. and adjust if you need to.
Doesn't matter what you photograph .. the important thing is to Understand the Histogram. :) I look forward to your feedback
well crap - I am leaving and won't be here for the histogram clarification. Well, I may get to check in for a little while tomorrow before i leave. I mean that makes sense and all but I am not sure I can put it into practice yet. I will give it some effort while I am gone - Vivian said she will do the broom jump and let me take pics of her "riding" LOL - it is so good to have friends that encourage your hobbies and have fun with you. :-)
Feb 25, 2012 04:14:07 #
photogrl57 wrote:
Welcome to Day 56 :) Take a deep breath .. get a c... (show quote)
Photogrl...I must say...This is the most I have ever understood the histogram !On a really good picture...will the spike be in the middle??or not nessesarily so...Ok..I understand the clipping part now ! Thanks !
chris
Feb 25, 2012 06:01:45 #
[quote=ces308]
Photogrl...I must say...This is the most I have ever understood the histogram !On a really good picture...will the spike be in the middle??or not nessesarily so...Ok..I understand the clipping part now ! Thanks !
Not always .. It depends on how balanced the colors are in the scene ... just when I think I know what it's going to do it fools me.
To me this photo does not scream perfect exposure ... yet look at the histogram .. that's why I say it is not the be-all end-all magic answer. This photo in my opinion could use an exposure compensation of maybe -1/3 or even
-2/3s of a stop.
But the colors are quite close so there is not much dynamic range there .. so the camera is happy .. but I'm not.
Photogrl...I must say...This is the most I have ever understood the histogram !On a really good picture...will the spike be in the middle??or not nessesarily so...Ok..I understand the clipping part now ! Thanks !
Not always .. It depends on how balanced the colors are in the scene ... just when I think I know what it's going to do it fools me.
To me this photo does not scream perfect exposure ... yet look at the histogram .. that's why I say it is not the be-all end-all magic answer. This photo in my opinion could use an exposure compensation of maybe -1/3 or even
-2/3s of a stop.
But the colors are quite close so there is not much dynamic range there .. so the camera is happy .. but I'm not.
Feb 25, 2012 06:13:56 #
Well PG, I was out yesterday and did some compensation work which I will use this morning on the histogram project, hopefully.
Now up here the old timers, I mean the old, old timers ,those who were old timers before I became an old timer would use brand names for things to identify them, f'instance a snowmobile was never a snowmobile, it was/is a Ski-Doo, the name that Bombardier, the inventor, gave it. Back then not everyone had a camera and those who were lucky got ''Kodaked''. no one took pictures, they ''Kodaked''
We are in a pretty good snowfall, about a foot so far, a sugar snow (snow that sticks to the trees) and you can bet what you're sitting on that I'll be be out Kodakin' and Histogrammin' this morning
Now up here the old timers, I mean the old, old timers ,those who were old timers before I became an old timer would use brand names for things to identify them, f'instance a snowmobile was never a snowmobile, it was/is a Ski-Doo, the name that Bombardier, the inventor, gave it. Back then not everyone had a camera and those who were lucky got ''Kodaked''. no one took pictures, they ''Kodaked''
We are in a pretty good snowfall, about a foot so far, a sugar snow (snow that sticks to the trees) and you can bet what you're sitting on that I'll be be out Kodakin' and Histogrammin' this morning
Feb 25, 2012 06:18:08 #
Roadrunner wrote:
Well PG, I was out yesterday and did some compensa... (show quote)
Awesome I look forward to seeing that ... I remember those days as well I still call them Kodak moments.
Feb 25, 2012 06:33:36 #
#3 is only to show the histogram as it looks like it had a Rivernan night
1/250, f.9, 0 comp ISO: 100
1/250, f.8 -1/3, ISO: 100
1/320 f.10 -2/3 ISO: 100
Feb 25, 2012 06:33:50 #
Chris it actually took me a while to find one that did spike in the center. By looking at this photo you would think it should be perfectly exposed. The histogram is very pretty.
This one is a perfect example of why we need to *fool* the camera. The painter (your camera) is very happy with this scene because all the colors are quite similar in range so he didn't have to work very hard to get the medium grey.
But to me there is nothing to get excited about here .. nothing pops. As it is I would post process this one. But If I had it to shoot over again I would go down probably -1 full stop.
This one is a perfect example of why we need to *fool* the camera. The painter (your camera) is very happy with this scene because all the colors are quite similar in range so he didn't have to work very hard to get the medium grey.
But to me there is nothing to get excited about here .. nothing pops. As it is I would post process this one. But If I had it to shoot over again I would go down probably -1 full stop.
Feb 25, 2012 06:36:06 #
Feb 25, 2012 06:38:54 #
Roadrunner wrote:
#3 is only to show the histogram as it looks like it had a Rivernan night
Snow is difficult .. because of the ton of white in there you might think about starting out at -1 instead of base 0.
and I'm sitting here laughing at the Rivernan night.
However all the color is in range .. so it doesn't have to be pretty to be good. If you begin with a -1 it's quite possible you won't need any more adjustment on it.
Feb 25, 2012 06:39:54 #
Roadrunner wrote:
Just a weird out...
brrrrrr it looks cold .. too bad it won't get up into the 50s and sunny today for your photo shoot.
Feb 25, 2012 07:16:48 #
In snow I switch back and forth, the nthe sun comes out and I put on a polaroid and it startsdall over again
Feb 25, 2012 07:46:41 #
Good morning, All. No funny picture today. Got some more nice morning snow shots, but might not even get them off camera today. (That KILLS me) Picture wasn't in today's newspaper. I am thinking tomorrow's, Sunday, because the submission was to the Outdoor section of the Sunday paper. Histograms. Yup, checked and I surely do have them, read them often, and know what they are suppsed to mean. Sometimes I don't like the corrections. Bye for now. Boys are calling.
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