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I heard that RAW Data is not the rendered data, which means it can’t be influenced by white balance, saturation, and all other settings.

I believe that “RAW Data” is influenced by the intensity of light but not the color (colors can be altered later as they are not the part of “RAW Data”)

Which means “RAW Data” can be influenced by “Exposure Compensation”

Now my question is, if the camera can show histogram which is rendered which means already influenced by color and other settings, then how can we decide correct level of light intensity (Exposure) which is relevant for RAW shoot (RAW Data) based on this camera Histogram (JPEG Histogram)

What Approach we will use to analysis camera Histogram (JPEG Histogram) for taking decision for RAW Shoot ?

There are 5 types of Camera Histogram (JPEG Histogram)

  1. Luminosity (Light),
  2. RGB (composite Light),
  3. Red,
  4. Green,
  5. Blue

Do we use Camera histogram - “Luminosity (Light) histogram” and “RGB (composite Light) histogram” out of 5 histograms for RAW Data exposure analysis purpose as this gives a rough idea of exposure level which is actually required for RAW Data Shoot ?

----------------------------Updated question in simple words--------------------

"To above question, I am adding more filtered/sorted line to understand easyly :"

What approach (things we do/any setting in camera?) while shooting in RAW to decide correct exposure and our Camera/JPEG Histogram shows the nearest graph for RAW ?

Please tell me in very easy layman language example : so and so setting name/terminology what camera manufacturer used as I will be searching those terms in manual to do settings you can take base as Sony A6500 or Panasonic G9

Thanks.

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In short: using the histograms correctly requires experience.

Though your assumption that raw data isn't influenced by colour is not correct, in the sense that colour information is stored through the effect of the bayer filter matrix. So light of the same intensity, but different colours (spectral compositions) will give a difference in the raw data.

And of course the raw data is influenced by the exposure compensation, as that changes the exposition parameters (time, F-stop and/or ISO, depending on shooting mode).

As for the histogram, it is based on the processed jpeg.
But in the normal shooting modes (PASM*), that processing is rather straight-forward, so with some experimentation (and perhaps modifying the camera settings) you can get a very good idea how much headroom you have left. E.g. after testing, you know that if the histogram is just not clipped, you can safely over-expose by 1.5 EV relative to the non-clipping exposure. But, your out-of-camera jpeg will look seriously over-exposed...
In addition, depending on your subject, you may not mind over-exposing parts of your image, if that means you get a better rendition of the shadows.

Note that to get the most reliable results when using the histogram to "expose to the right", you shouldn't use any setting that increases the apparent dynamic range of the processed image, you want your in-camera jpeg to get as little processing as possible.
(Those increases in the dynamic range are obtained through manipulation of the highlights in jpeg processing, exactly the part of the histogram you want to use to judge your exposition...)

I never use the scene modes, as they are largely irrelevant for my raw processing (many raw converters can't use the scene settings), so cannot comment on what happens there.

For normal situations (i.e. no predominant colour in the scene), the "luminance" or "composite light" is the histogram I usually use. If an important part of the image is occupied by a strong colour (e.g. a close-up of a red flower), I prefer using the individual channels. Especially red can be problematic here, and blues at the far end of the spectrum.

(*: P - programmed, A - aperture selection, S - shutter selection, M - full manual)

  • A few days back I posted on dpreview regard difference between RAW and JPEG all told me that White Balance doesn't affect RAW data itself but they are just the settings to present RAW in viewable form. so does WB affect RAW Data ? as you told in the first paragraph. – user74181 Mar 24 '18 at 10:43
  • No, WB settings don't affect raw data, but colour (of the incoming light) is visible in the raw data – remco Mar 24 '18 at 10:49
  • I heard WB is used to influence RGB does that mean colors after sensor Bayer Filter RGBG already taken which means that WB is not influencing sensor Bayer filter RGBG so it is not influencing RAW DATA ? Pease say "yes" or "no" because no body is answering me in simple words every answer is googly of words – user74181 Mar 24 '18 at 10:57
  • can you please... explain me in simple words "please..." that what settings I have to do in camera to make Camera/JPEG Histogram appear losest for analysis RAW Data exposure – user74181 Mar 24 '18 at 11:04
  • @Tushar: I'd rather suggest you try a series of test shots (ideally with the camera on a tripod) with different amounts of exposure compensation, and then look at what the result is. Shoot in raw+jpeg mode (in one of the basic modes, and without what Sony calls 'Dynamic range optimizer) , so you can look at the results after downloading the images. – remco Mar 24 '18 at 12:10
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You basic question is pretty much a duplicate of several we already have here, including How to avoid overexposing image using RGB histogram when shooting RAW and using different Picture Controls?

But there are a few misconceptions in the question that should probably be addressed before sending you to those other questions/answers for the information you seek.

Which means “RAW Data” can be influenced by “Exposure Compensation”

Only indirectly. Exposure compensation only alters the exposure values the camera uses to take the shot: shutter duration (Tv), aperture (Av), or sensitivity (ISO). It does not alter the raw data collected by the sensor using those three exposure parameters in any way.

It seems that some folks think that entering an EC value results in the raw data from the sensor being processed differently than if the same ISO were selected with a different EC value.

This is not the case at all!

The only thing that controls the amount of amplification of the analog information coming off the sensor before it is converted to raw digital data is the ISO setting. An image taken using [-3 EC] that resulted in the camera using ISO 400 will result in the exact same sensor amplification as an image taken using [0 EC] or [+5 EC] that resulted in the camera using ISO 400.

What matters with regard to sensor amplification is what the ISO is set to when the image is taken. Period. How a particular ISO is selected matters not: whether chosen by a manually entered ISO setting or by an automated program resulting from use of EC, a specific ISO value will always result in the same amount of sensor amplification. ISO 100 has the same signal amplification regardless of whether EC is set to -5, 0, or +5 at the time the image is exposed.

For a more thorough explanation, please see this answer to What is exposure compensation? as well as Why did the shutter speed increase when I raised ISO and lowered exposure compensation in Aperture Priority mode? and How does a film camera perform exposure compensation?

I believe that “RAW Data” is influenced by the intensity of light but not the color (colors can be altered later as they are not the part of “RAW Data”)

Not exactly. Since the imaging sensor of the vast majority of digital cameras have Bayer color filters arrays in front of them differences in color can influence exposure. This is particularly the case if the light being captured is much brighter in the center of one color channel than the other two.

For more, please see:
Blown out blue/red light making photos look out of focus
Why is it that when the green channel clips, it turns into blue?
Do I still need to use color filters for images that are to be presented in monochrome (B&W)?

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