Hi there.

The histogram as you might know is basically a recording of the light levels that the camera recorded when the sensor was exposed.(to the light,image).

If looking at your histo and most of the detail is to the left of the centre... it means that you either had a short exposure time and the shot will tend to be underexposed (shutter speed very quick,relatively speaking) or the apeture used ,chosen, was too small, i.e not 1.4 or 2.8 but more to the 11,16,22 side of things..

If however the histo shows detail on the right side of the centre the exact opp applies, overexposure.There is not really a right and wrong as long as you are not too extreme with these settings i.e over exposing or under exposing..

Getting to know shutter speed and aperture will be the key to better understandind the histogr..

Hope this helps you.

Good luck with the shooting.

Don..

Here's the tutorial I read back in the day to understand histograms. It's written by Shay Stevens who used to visit these forums a lot. This tutorial focuses on the Sony F717 and the spot meter, but should be good enough to gain a basic understanding of using the histogram and the zone system of exposure..

Http://www.digitalsecrets.net/Sony/AdvancedKnow.html.

Joe.

My craptacular photos: http://www.pbase.com/pyogenes/favorites.

Any perceived rudeness, condescending tone, or insults are not intended, but rather the result of my inability to properly express myself with the written word...

Don Ross wrote:.

If looking at your histo and most of the detail is to the left ofthe centre... it means that you either had a short exposure timeand the shot will tend to be underexposed (shutter speed veryquick,relatively speaking) or the apeture used ,chosen, was toosmall, i.e not 1.4 or 2.8 but more to the 11,16,22 side of things..

OR it could also mean that the object you photographed was very dark in shade..

If however the histo shows detail on the right side of the centrethe exact opp applies, overexposure.There is not really a right andwrong as long as you are not too extreme with these settings i.eover exposing or under exposing..

OR it could mean that you object you are photographing is very light in shade.

In normal light with a mixed scene you would expect a mound in the middle which should extend outwards and almost touch extreme left and right but not quite..

Historograms are a guide. They are not 100% accurate. If you look at the same shot in camera and then on different processing programs you will have the same basic shape but the exact contours will vary slightly.Chris Elliott.

*Nikon* D Eighty + Fifty - Other equipment in Profile.

Http://PlacidoD.zenfolio.com/..

Sondrad wrote:.

I'm such a newby. I understand what histograms are, just not surehow to use them. Are there any good tutorials?.

We were all starting out at some point in time, so you're not alone. So many nice people have helped me in the past in these forums and it's a kind of pay-it-forward scheme, so I'll grab the rare chance to contribute. Here're are a bunch of the best links- all of them about histograms! Do take your time to read and assimilate the idea..

Http://www.cambridgeincolour.com/tutorials/histograms1.htmhttp://www.cambridgeincolour.com/tutorials/histograms2.htmhttp://www.ronbigelow.com/articles/exposure/exposure.htmhttp://www.sphoto.com/techinfo/histograms/histograms.htm.

Http://www.luminous-landscape.com/...ng-series/understanding-histograms.shtmlhttp://www.dpreview.com/.../learn/?/Glossary/Digital_Imaging/Histogram_01.htmhttp://www.ximinasphotography.com/lessons/lesson04/lighting_3.htmlhttp://www.outbackphoto.com/workflow/wf_41/essay.htmlhttp://www.shortcourses.com/how/histograms/histograms.htmhttp://www.digicamhelp.com/...amera-features/advanced-settings/histogram1.phphttp://www.bythom.com/histogram.htmhttp://500th.net/histogramhttp://www.earthboundlight.com/phototips/histogram.htmlhttp://www.outbackphoto.com/workflow/wf_56/essay.html.

Here're some other ways in which histogram can be your good friend-.

1. While shooting one cannot trust the camera LCD display to make exposure evaluations reliably. This is because of variable LCD brightness relative to outside light, limited LCD viewing angle, insufficient zooming capability, etc. Rely on the histogram even if your eyes tell you otherwise when you look at LCD image in playback mode. Also, if you shoot RAW, the histogram shown on the camera LCD is an approximate one since it is usually computed based upon the in-camera jpeg data..

I have even seen claims from users that their camera histogram is most accurate while in Adobe RGB color mode ( the accuracy of in-camera histogram as compared to histogram as seen in say, photoshop ). Practically, camera histograms should work quite well even in sRGB mode..

2. I have LCD screens on my desktop and laptop as well, and they both do a poor job of showing accurate colors and brightness levels. Laptops are more problematic because the screens can be tilted, and also they can be carried away to another place where ambient lighting has changed- so are harder to calibrate. Again, histogram can come to your aid here..

Hth,AP..

Great information by all...I had the same question and took a 4 week class from betterphoto.com and now I have a much better understanding and know why my photos are turning out the way they did and the way the are now. Very good course. The other urls posted in this thread were good as well. One key to understand is to know what it means by shadows - underxposed and highlights which is overexposed. There are different theories in regards as to where the bulk of your histogram information should be along tonal...it really depends on what you are shooting, something dark or majority dark background may be perfectly composed witth shadows, for example...

....it really depends on what you are shooting, something darkor majority dark background may be perfectly composed witthshadows, for example..

So, to expand on my earlier answer, a historogram with a hump to the right WITH A DARK SUBJECT would be overexposed..

The metering system on your camera assumes everything is mid-gray and should have a large mound in tne middle with anything that is. It tries to lighten anything darker whixh it assumes to be underexposed and vice versa..

But your photo is colour. You really need to check all 3 channels separately if possible. Typically blue and green will be fine but red may be blown. That will affect the colours of your photo. E.G. You shoot a scene with bright blue sky and deep deep shadows.

If you try to adjust the image post processing it likely your sky will turn light gray because there will be no information in the clipped section of the blue channel to fill the gap..

Small footnote: Traditionally a historogram is shown with a scale 0-256. Even if you shoot RAW (commonly 12 bit) the graph will use that same scale..

Do remember the graph is a good guide but not 100% accurate.Chris Elliott.

*Nikon* D Eighty + Fifty - Other equipment in Profile.

Http://PlacidoD.zenfolio.com/..

OMG! Thank you so much. I'll be sure to pay-it-forward some day, too...

Great answers above. Also see my photographer's notebook page on histograms: http://halley.cc/photo/histogram.html with some image examples..

[ e d @ h a l l e yc c ] http://www.halley.cc/pix/..