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How to use live Histogram in effective way

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How to use live Histogram in effective way
« on: 04 / January / 2012, 07:43:20 »
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I have read some article about using live Histogram.
I didn't get it actually, How to use this feature while you are shooting.

I understand that if the curve is in left side that means black dots are more and white dots are less or vice versa but if I am taking picture what should  I care about in histogram  ::) ??? ???
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Re: How to use live Histogram in effective way
« Reply #1 on: 04 / January / 2012, 08:01:08 »
The x-axis (horizontal line) represents the different tones, ranging from the shadows (dark parts of the image) on the far left to the highlights (bright parts of the image) on the far right, with the midtones in between (thus the name).

For most scenes, the best exposure would be where the histogram shows a bell curve, with the highest part in the middle and getting lower on both sides. However, as stated, this depends on the scene, and might not be ideal in particular circumstances (for example when shooting the moon which is surrounded by total darkness, or when shooting a very bright object such as bride's white dress, sand or snow).

It is helpful in 2 ways:
  • Firstly, it allows you to judge whether the photo is exposed correctly since sometimes this might be difficult on the camera's LCD.
  • Secondly, it shows you whether you are clipping the highlights or the shadows. Clipping means that you are loosing details in those areas. For example if the image is overexposed (image is too bright), the highlights are clipped and details are lost in the brightest areas.

Have a look at this link for a detailed explanation:
http://www.luminous-landscape.com/tutorials/understanding-series/understanding-histograms.shtml
« Last Edit: 04 / January / 2012, 08:03:29 by mdebono »

Re: How to use live Histogram in effective way
« Reply #2 on: 04 / January / 2012, 09:43:13 »
Good idea is just to experiment - try to use different exposures and then look, when your pictures are best.
As mdebono said - sometimes you might be not able to judge wheter the exposure is correct basing only on LCD display. For example it the sunny day it might be difficult to see it on LCD - it's not enough bright. But you'll see histogram at least and it can help you:)

BTW - remember, that CHDK histogram is based on LCD live view. And camera creates live view basing on settings you have set - shutter speed, aperture and ISO. If you use CHDK overrides, then camera don't know about that until it get shot, so live view will be not acurate. According to this - CHDK histogram will be not very usefull in that cases.
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Re: How to use live Histogram in effective way
« Reply #3 on: 05 / January / 2012, 02:06:43 »
I have read some article about using live Histogram. I didn't get it actually, How to use this feature while you are shooting...what should I care about in histogram...
Here are a few links that may help:

A PRACTICAL GUIDE TO INTERPRETING RGB HISTOGRAMS
http://www.sphoto.com/techinfo/histograms/histograms4.htm

How to Use Histograms (KenRockwell.com)
http://www.kenrockwell.com/tech/histograms.htm

How to use the histogram to get a better exposure
http://photonaturalist.net/how-to-use-the-histogram-to-get-a-better-exposure/

Digital Photography School: Understanding Histograms
http://www.digital-photography-school.com/understanding-histograms

 

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