Camera Labs

Hi,
As somebody who still has lots to learn, to improve images is it important to understand the actual mechanics of a histogram graph?
Would it help with under/over exposure or high and low key images?
Just wondering if it's worth really studying this or just let the camera do the work.
Are there more important aspects to concentrate on, perhaps composition?
It seems to me histograms are everywhere, on the camera and software, so is it just for pros or can it benefit everybody if only they took the trouble to find out a bit more.
I would be interested to know if it's a sizable part of lengthy courses at uni or such like.
regards John

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Nikon D80, D40 and various lenses.

No offence but somehow I doubt that learning how to read a histogram would be a lengthy part of a course at uni

There's not really much to reading a histogram even thought I don't really bother, purely because I know that I have the time to review the image after i've taken it, and retake it. If however you have the preview set to show the histagram, then it could shave off a few miliseconds and mean you getting a second shot thats of the right exposure, before the shot is lost if you get what I mean. Otherwise it's just a surefire way of seeing if the shot is exposed properly in conditions where you can't rely on the screen. I.e in bright sunlight, or in darkness where you might think the shot is exposed fine and isnt.

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I've upped my Iso, now up yours.
Nikon D700, Nikon D80, Micro Nikkor 105 f2.8 AI-S,Nikon 85mm 1.8D, Nikon 50mm 1.8D, Nikon 35mm F2D, Nikon 16-35 f4 VR, Nikon 24-70mm F2.8 AF-S, Nikon 70-200VRII, Nikon 70-300mm VR, 300mm f2.8 AI IF ED, SB-800, SB-900. Noiseware pro,NIK Dfine, Nik Colour Effex, Nik Sharpener Pro

If you want to know more about understanding histograms you should find these two articles over at Cambridge in Colour quite interesting:

http://www.cambridgeincolour.com/tutori ... grams1.htm - I suggest you read this one first.

http://www.cambridgeincolour.com/tutori ... grams2.htm

Mark

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Canon EOS 40D / EF-S 17-85mm IS / EF 50mm f/1.8 / My Flickr

thanks guys,
Mark they are really useful links thanks alot mate.
John

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Nikon D80, D40 and various lenses.

I have started to use the histogram on my camera recently as I was fed up with dark corners and white skys. It took me a while to understand it but I think I may have summed it up by saying " too much right = too bright" or maybe I have it wrong.

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Life through a lens but not as it seems Jim.

I general, that's correct. Although it varies greatly from image to image.

Mark

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Canon EOS 40D / EF-S 17-85mm IS / EF 50mm f/1.8 / My Flickr

The thing is too, is that you can see, on the fly, if you'd be able to save the image in PP, as long as you haven't blown your highlights too much (washed out skies, water, metal, etc). Too much white/right, delete and try again!

Of course being able to know if you have a 'decent spread' of colour is valuable too, as well as under-exposed areas which in PP will give you too much noise.

Basic histogram interpretation to me is an invaluable ability.

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Canon EOS 5D MkII | Canon EOS 7D | Canon Digital Rebel XSi | EF 35mm f/1.4L | EF 50mm f/1.8 II | EF 85mm f/1.8 | EF 100mm f/2.8 Macro USM | EF 135mm f/2L | EF-S 18-55mm f/3.5-5.6 IS | 580EX II | LumoPro LP-120

My Flickr

I use histograms more after-the-fact in post-processing where I can lighten and darken in Photoshop and get instant feedback. We do 4-color process printing where I work and they come into play in relation to the press. RAW saves the day for me. Plymer pointed out that use of the RGB histogram may prove helpful as well, which is what I use in tandem with brightness.

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http://www.flickr.com/photos/nursediesel
Canon EOS 5D & 5D2 | EF 70-200 f2.8 L IS | EF 100-400 f4.5-5.6 L IS | EF 24-105 f4 L IS | EF 17-40 F4 L | 580 EX II | Fujifilm X10

Very interesting guys. Still struggling to find an instant correlation between the image and histogram but I'm trying.
regards John

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Nikon D80, D40 and various lenses.

GCJ: The thing I keep in mind is left is dark - right is light - it's best to have a balanced image with the curves spread evenly over the entire span of the histogram instead of bunched at one side or the other. If they're bunched at the left use +EV if at the right -EV or adjust your ISO up or down, shutter speed up or down, etc. Any of these things can help to even out your image. Hope this was helpful.

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http://www.flickr.com/photos/nursediesel
Canon EOS 5D & 5D2 | EF 70-200 f2.8 L IS | EF 100-400 f4.5-5.6 L IS | EF 24-105 f4 L IS | EF 17-40 F4 L | 580 EX II | Fujifilm X10

The most important direct correlation is that whenever you see the histogram being 'bunched up' against the right or left edge of the histogram that means you will lose dynamic range in either the light or dark part of the shot you are about to make that you will NOT be able to recover in PP. That will be lost forever. You'll get ALL WHITE where there should be 'shades of white' or ALL BLACK where there should be 'shades of black'.

Ben
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When in doubt..... Press the shutter.

thanks

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Nikon D80, D40 and various lenses.

I don't normally look at my histogram but if shooting in bright sunlight, it is invaluable. The image isn't always fully visible in bright light but the histogram can still be seen fairly well, well enough to warn me of clipped highlights and shadows. I also use this with indoor flash photography so I can watch my highlights.

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Graham
Flickr