Histogram difference - camera vs darktable.

I don’t have a Canon - so I’m guessing here - but on my Sony, using ‘DRO’ (dynamic range optimizer I think) has the effect of lowering the exposure, then the camera pushes the shadows and midtones back up.
So the jpg looks like a normal exposure, but with more highlight detail. But the RAW in dt is darker, as dt obviously doesn’t recognize Sony’s exposure tinkering.
Maybe your Canon’s D+ is doing something similar?
I don’t know much about the histogram in dt…

Hi

My understanding of natural live view is that it provides a optical viewfinder like view (DSLR if you will) in the electronic viewfinder. Quite useful if you are working in very low light, otherwise not (in my view, YMMV). Film simulations are not turned off and any other tweaks (higlight tone, shadow tone etc) are as set by you in settings.

The nearest thing you can get to a raw histogram (and raw blinkies) is to set up a custom profile as below:

Settings > IQ settings > edit save custom settings
DR100
D range priority off
Film sim Pro neg std ()this is a very flat simulation)
Grain OFF
Highlight -2
Shadow -2
Colour 0
Sharpness whatever
NR whatever

Hope this helps.

Not sure where you got that idea from, but Fuji’s own literature suggests differently:

Choose whether the effects of film simulation, white balance, and other settings are visible in the monitor.

OFF: The effects of film simulation, white balance, and other settings can be previewed in the monitor.

And

Turning Natural Live View ON disables the visual effects of in-camera JPG processing. This includes film simulation, white balance, shadow/highlight adjustments.

Yes, in the viewfinder. Not what’s recorded in the file - that keeps film sim, and other adjustments. Apols for not making that clearer. From the X-H1 manual in front of me.

I can’t see how (in effect) artificially boosting shadows and back lit subjects is going to help you get a more accurate result, since the raw file will not have those areas artificially boosted.

Another Fujifilm oddity you may not have noticed. With natural live view off (which is where it should be almost all the time) the only time you have true what-you-see-is-what-you-get (in terms of exposure) in the EVF is if you are in full manual mode. If in full auto or aperture or shutter priority the EVF shows you what the camera thinks you probably want.

This… A thousand times this.

Almost always the ‘embedded JPEG’. i.e., what your camera would call ‘the final picture’. Like others have said, maybe with alternative firmwares, but I don’t know of a camera that has a RAW histogram out of the box.

My easy - and harsh - answer is: ‘you cannot relate’. And maybe you shouldn’t even try.

Things like that ‘D+’ setting you talk about. Some cameras have modes like this that actually alter the exposure and compensate in the ‘developing the picture’ step (so they actually shoot darker than you think, but compensate the final JPEG file. This way you preserve highlight data, also in your RAW file). Others just adjust the curve they use to make the JPEG (so the tone curve they apply will leave more detail in the highlights, but the shot itself is not technically different, so the RAW file should be the same, which means you still need to be careful not to clip your highlights).

See it that your camera has a ‘built in RAW converter’, and the histogram you are seeing is for what the camera is doing ‘in the edit’. Darktable is another RAW editor, so will do different things to your captured light-data, so will display a different histogram.

I always walk around at -1EV or even more by default on sunny days. But I know that I’m more allergic to clipped highlights than to noise, and my cameras doesn’t add a lot of noise in the shadows.

Your D70 is one of the older Canon’s that’s notorious for noise added to the shadows, even at low ISO’s. So what you might want to do depends on how allergic you are to noise or to clipped highlights. That’s something only you can decide.

But that D+ mode is a typical ‘make shot too dark, compensate for it in the edit’ from what it seems like. So it’s only natural that you have to do the compensating yourself when you open the RAW in Darktable (because the camera only did the compensating in JPEG, not in RAW so to speak).

I would happily use something like that, but as I said, I don’t mind a bit of noise, or I’m not afraid of it. I can’t decide if that’s true for you, or how big the noise problem is on your camera, etc…

Try it out, is all I can say. Experiment a bit.

The image you chose at least as far as I can see is from here ??

Not this thread but I may be missing something in a historical reference???

Yes, my point was that it effects what you see on screen, including the histogram, but not the raw data. So when I was usinf this feature I ended up clipping all the highlights. It makes no sense to me why it even exists, I only shoot in manual mode.

@Terry I didn’t provide an image actually - just screenshot of the histogram and link to a previous post that the user was having some challenges too.

The screenshot b/w with histogram in the middle is how my image looks on the LCD - in essence - centered histogram without visible clipping left or right

Thank you!
This video is very informative!
I think I will have to go for a manual adjustment to handle properly the highlights.

@jorismak Thank you!
I think I will have to experiment more with it. Yes - I’d rather have the noise than the highlight clip. Even when I don’t like the noise either.

Canon’s “D+” , Fuji’s “Dynamic Range” … They do the same thing - underexpose, without you even knowing, in order to save extra highlights and then raising darker parts “in post” , i.e. when baking JPG (or RAW thumbnail).

Please notice - when you use D+ in Canon or DR in Fuji, you are no longer able to select the lowest ISO.

(Well, in Fuji you can, but then DR goes back to DR100%, which is the same as “OFF” )

Plus, the histogram shown in camera is based on embeded JPG thumbnail, which in turn is based on the “Picture style / Film simulation / Picture control / etc” you had chosen before.

Darktable alwyas shows the real RAW, while most commercial software reads the EXIF tag of dynamic range modes and silently adjust the image’s brightness.

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I think that many people set up the highlight warnings and then take some test shot increasing the EV in small increments and then come up with a fairly good guide of how far they can push the DNR of their camera…maybe this changes for different lenses not sure but it seems like a robust and quick way to be able to work quickly without too much fiddling…

Thank you…
My photos were vacation photos - often on the go with few sec. time to adjust…
Didn’t have time to properly assess.

I think this is what happens indeed. I will try to turn OFF D+ then manual adjust to slightly under expose -1/3 to -2/3 to deal with the highlights.

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I’d hope that once you get all the wacky jpeg-first stuff disabled that you’ll find that you generally have +1/2-1stop of headroom from the jpeg. That’s how its been for the other systems I’ve shot on.

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One item not discussed is the metering modes on the camera. Those will have a big effect on the exposure compensation.

I recommend switching your camera to M (manual mode). Keep the iso at 400 and learn how to expose on your camera. Keep it there for a month or more. Correlate to darktable and then eventually switch to A (aperture). If you do this, you won’t be looking at camera histograms.

My answer to this problem is to set the camera to auto exposure bracketing of 1EV. With continuous drive the camera quickly gets the three shots and this covers me in most situations. Also reduces the chance of a person having their eyes closed because of blinking. Camera sounds more professional as well so the BS factor makes you look like a better photographer.

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:grinning:
I’ve done this quite a bit. Have 9k photos to sort :shushing_face:

My information regarding Fuji cameras, differs from yours: as I understand it the ‘L’ histogram is directly taken from the display/JPG data but the R.G.B. histograms are from the RAW data.
I follow the advice from AP and allow the camera to establish the exposure ‘pivot-point’ (mid gray). My Fuji underexposes this value by a full (protective) stop, which I reverse automatically in processing. The only other exposure correction that I make is through the camera’s compensation control which again is automatically reversed as a part of the exposure preset.
In general I find that only very rarely do I need to mess further with exposure during the development process.
I believe that this way my exposure/development pivots around the 18.45% and filmic takes care of the tone mapping as needed. Using ETTR as a basis for exposure appears to me counter-productive with this ‘modern’ system.