17

Simple: the color of the sky is comprised of the mix of all three channels. If it were gray, there would be equal amounts of red, green, and blue. It's not, though — there's a lot more blue, a little less green, and very little red. Pretty much like this: Check out how the arrows on the slider are pretty much exactly at the same percentages as the spikes in ...


15

You activated by mistake an advanced view mode. You can switch between view modes by pressing "info" (or maybe "display" for you) when in view mode. The view switchs in that order (sorry for image quality) : Classical View : your photo and some settings and nothing else Classical View with more information : your photo, some settings image quality (JPG/...


13

The general rules for histograms still apply, it's just that most of the "weight" of your histogram will be leaning to the left: Your aim will be the same: keep as much of the data in the histogram from clipping at the right hand edge, without leaving too much way down the left hand side. You should be able to see some data reaching all the way across the ...


13

Why don't cameras show a histogram based on the RAW data rather than on the JPG preview? My notion is this: Because it would not be useful, because raw images don't yet have white balance in them, but the JPG images do have WB. For example, Daylight white balance will shift the red channel substantially higher, and the blue channel substantially lower. ...


13

It's all to do with the profile applied to the raw files and guesses other software makes as to what that profile ought to be... RAW is not an 'absolute' format in terms of the image displayed, it's raw data to which an 'opinion' of what the image ought to look like can be manipulated from. It will already contain several view options added by the camera, ...


11

It doesn't exceed the top of the histogram scale. That may appear common, only because histograms are always normalized. Data is intentionally scaled so that the peak value reaches the top (this shows low values better). And the exact count is unimportant. The range of distribution is the only thing important. So all histograms approximately reach the full ...


9

The scale is somewhat arbitrary, and it is adaptive. That is, it's automatically scaled in an attempt to remain as useful as possible, given the image and its current adjustments. If you create an image in Photoshop that has a perfectly even distribution of colour or grey tones (let's say a 256-pixel image with one pixel each of every shade of grey from 0,0,...


8

I don't think this technique is used widely if at all. Aside from giving broad information about exposure, the particular shape of the histogram is very specific to the image content, so forcing an image to conform to the histogram of a different image would be pointless and quite likely eliminate detail in certain areas. The only possible use would be if ...


7

You will always have one value touch the top of the graph because the scale is set to match the max Y value. It's not important what that Y value is, only it's relative proportion to the other Y values (hence, no numbers, ever). Below is an image that is 50% black and 50% white and you can see the graph is peaked on both sides. You can't see it in the ...


6

Histogram is the best way to judge. How are you shooting? If you're shooting in JPEG, you should check your camera settings to see if you have the brightness turned up or contrast down or something strange like that. Assuming you're shooting in raw and opening the files in something like lightroom, then you're probably actually overexposing. Because ...


6

Without referencing a white object in your photo, we cannot decide which one has a better white balance. In short, white balance is process of removing unrealistic color cast on your image, i.e., correct the white area in your image that captured as gray. So it cannot be judged by histogram. If you know what part of your image should be white and the image ...


5

The histogram in Lightroom 3 does change. Here's an example: Full frame Cropped You'll note that the cropped image has more image information in the top third of the histogram, whereas the uncropped one has more in the lower third. That's what you would expect. So the question is, why aren't you observing this? Are you using Lightroom 3?


5

Entangle shows the histogram of the JPEG image embedded in the RAW file, in logarithmic scale. RawTherapee, on the other hand, shows the histogram in linear scale, shows the histogram of its pre-processed form of the RAW file, not of the embedded image. This explains the difference. To see histogram of raw data just enable the Show/Hide raw histogram ...


5

Raw image files contain enough data to create a near infinite number of interpretations of that data that will fit in an 8-bit jpeg file.¹ Anytime you open a raw file and look at it on your screen, you are not viewing "THE raw file." You are viewing one among countless possible interpretations of the data in the raw file. The raw data itself contains a ...


4

Simple answer: You can't tell how the photographer exposed the images and you won't learn anything about that from looking at the histograms of the processed photos. Chances are that the photographer is shooting in RAW and that the photos are post processed quite a bit. In post you can drag the exposure (that results in a pushed histogram to the left or ...


4

The human eye is more sensitive to green light than red or blue. For that reason, digital sensors have twice as many green photosites than red or blue. The overall luminance of an image, then, is more dependent on the green channel than red or blue. So the luminance histogram will look most like the green histogram. So if the dominant colours in the ...


4

Have you check RawDigger. As far as I know it show really raw histogram


4

The majority of cameras use the JPEG preview (with picture styles applied) embedded in a RAW file as the source data for the histogram and blinkies. In other words, it's just using what's sent to your LCD display for review. This is probably due to limited processor load and data paths, and is a cause for complaint among photographers--that the data they're ...


4

Yes I would agree the left image has more contrast, for two reasons. The main one is that because the right image is underexposed, there is lost detail in the blacks and the highlights don't extend to the edge of the histogram, so no pure whites, while the first image covers the full extent between 0-255. Also there is a larger peak in both the shadows and ...


4

I always attempt to bring the image to what the scene looked like with the naked eye when I was there. Basically, I’m wondering if I am capturing all the necessary data to achieve this in post processing when the histogram shows there is no clipping at either end. For example if the sky was a very saturated orange, is it necessary to add a shot that is ...


4

First thing to do is to check the "mode" of your histogram. Darktable has three ways to visualise the histogram. One is the 'normal' one, which is linear in intensity, the second is logarithmic in intensity, and the third is a "waveform" display (I never figured out what the use of that one is). To see which mode is displayed, hover your mouse over the ...


3

A histogram is useful in two general areas: When taking a photograph, one can use it to judge exposure and dynamic range. When evaluating a processed photo, one can use it to help deduce some information about common post-processing techniques. First, quick background: a histogram is a special kind of bar graph where, for a set of data, similar values are ...


3

My question is - can I tell which photo has more contrast from the histogram? You can and you can't. You can tell to the point. A narrow histogram generally indicates a fairly flat image, while a broad histogram generally indicates good contrast. So your image on the left has better contrast because it extends further into the Whites than the image on the ...


3

The width of the histogram shows the dynamic range (contrast) of the image. There are 255 columns. One column each for 255 different values from black to white. Wider is more contrast. If you have a column in the black and a column in the white, you have the maximum contrast image that the histogram is capable of showing. The height of the histogram ...


3

Let us see what the axes of the histogram represent. I started with a simple gradient which has overall the same amount of pixels of each luminosity or brightness intensity. Then I am adding a single zone of one gray, therefore more pixels of that particular gray are present on the image. The gradient is the same, but as I add more gray pixels the ...


3

That looks to me more like noise, particularly chrominance noise, than posterization or banding. But the two things can look very similar at times, particularly if too much compression was used when converting to JPEG.¹ There are some noticeable compression artifacts near the edges between the red sleeve and the background. When one underexposes a shot and ...


2

The trouble with UniWB is that you sacrifice color display for histogram accuracy. It is a bit too much for my taste, I leave WB on auto usually. Instead of using a neutral setting, I even set contrast and saturation to lowest settings. The result matches the RAW relatively well on my camera. Just give it a try.


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