How do influence a raw image creation?

[RalphLambrecht]

What camera settings, other than shutter speed and aperture, affect the raw image file? In the case of my Nikon D700, how about:

1. active D-lighting
2. contrast changes
3. color modes

Are they all for just JPG and TIFF output or do they affect the raw image file as well?

 

[2F/2F]

Hi,

Active D-lighting (different than D-lighting) actually applies negative exposure compensation in the camera (which is what makes it "active," I believe), in order to help you hold the high tones. Then if you convert the NEFs in a Nikon program, the lower tones are brought back up the same amount, while the highs stay where they were exposed. I don't think the lows are raised in tone in anything but Nikon software, but I may be wrong on that count.

You can set it manually in three intensities, or put it on Auto (or Off, of course). If I had to take a guess, I would assume that Low is -1/3 stop, Medium, is -2/3 stop, and High is -1 full stop EC, while auto picks one of the three for you, depending on what the meter is seeing. I'm really not sure how much is the maximum that it will underexpose on Auto mode. It may be the case that on Auto mode, it will go beyond 1 stop; but I think this is doubtful, as Nikon probably doesn't want people getting badly underexposed shots, even for the purpose of retaining high-toned texture and detail.

So, basically, Active D-lighting is a built-in way to do what digital photographers have done for as long as there have been digital cameras: underexpose to retain highlights, and then raise the shadows in the computer. It is a reverse method of achieving what is done when you overexpose and then underdevelop a piece of film (though due to the possibility of noise and loss of low-end detail and texture, I would argue that the film method will provide "better" results, as nothing is thrown away from the low end that way).

Contrast changes affect the LCD image, tiffs or jpegs (if that is what you are shooting), and carry over into the editing controls of a Nikon raw program. But they do not change the actual sensor information stored in a raw file (though they do encode the camera settings in the raw file so that they can be read by a conversion program); you can change them after the fact if you made the wrong choice with the camera settings. (AFAIK, actual changes to a raw file are impossible. A raw file is simply exactly what the sensor caught, which is used to build an actual image file.) This statement is based on my general digital knowledge, and not the D700 specifically.

Color modes are probably the same as contrast changes.

(Boy, wouldn't it be nice if you actually could change the sensor's physical response to contrast and color! (That is what would be required to actually control what becomes a raw file in the camera.) If that is ever accomplished in a smart way, it will be the thing that truly pushes digital beyond film in almost all areas, in my mind. Wouldn't it be nice to simply dial in the ideal dynamic range to capture the brightness range of each composition, in the same way you would select different films and development routines?)

Unfortunately, in-camera color and contrast settings have no connection to the light meter, as does Active D-lighting. For example, if you were shooting using high contrast and Vivid settings, for the most ideal exposures, you would probably want to expose differently than if you were shooting Neutral or Standard, just like you might expose E100SW and E100VS differently. A workaround to achieve underexposure in these situations would be to apply manual exposure compensation or manual Active D-lighting. Still, more button mashing than should be necessary.

In any digital camera, I always keep the color and contrast settings as flat as possible if I am shooting raw. I want to see the closest possible representation of the "flat" raw file on my LCD, and that is where I want to start when I open the files on my computer. I do set white balance, however. (Never auto; I'd rather have 50 shots with all the same white balance in need of adjustment than have 50, each with a slightly different automatic white balance, most of which need adjustment.)

 

[keithwms]

Hmm I didn't think any of these things could change the RAW file. I mean, active D-lighting affects it in the same way that any exposure decision would, but I don't think it in any way reduces the total captured information.

Awaiting further input.

 

[markbarendt]

To the best of my understanding the raw sensor data is never manipulated, nor can it be viewed as an image directly.

That raw data must be processed through various layers of software to render an image visible.

Some of that software is fixed, like the Bayer pattern, but camera settings are not.

In fact many proprietary things like d-lighting may be totally ignored by Adobe software.

To get the d-lighting effects into Adobe you may have to "save as" a tiff or jpeg from Nikon software first.

 

[2F/2F]

In fact many proprietary things like d-lighting may be totally ignored by Adobe software.

To get the d-lighting effects into Adobe you may have to "save as" a tiff or jpeg from Nikon software first.

Hi,

In the case of D-lighting (not Active D-lighting), it is just a feature of the Nikon software that boosts the shadows in tone. But with Active D-lighting, there is actually an exposure reduction in the camera. This, of course, will carry over into any raw converter, whether or not the shadow boost does.

 

[markbarendt]

Hi,

In the case of D-lighting (not Active D-lighting), it is just a feature of the Nikon software that boosts the shadows in tone. But with Active D-lighting, there is actually an exposure reduction in the camera. This, of course, will carry over into any raw converter, whether or not the shadow boost does.

So does it adjust exposure that reaches the sensor?

Edit, duh. Misread your post the first try.

 

[donbga]

To the best of my understanding the raw sensor data is never manipulated, nor can it be viewed as an image directly.

That raw data must be processed through various layers of software to render an image visible.

Some of that software is fixed, like the Bayer pattern, but camera settings are not.

In fact many proprietary things like d-lighting may be totally ignored by Adobe software.

To get the d-lighting effects into Adobe you may have to "save as" a tiff or jpeg from Nikon software first.

Nikon manipulates the data that gets written to the RAW file on some of their camera models. For example, in some cases sharpening is automatically applied without the control or intervention of the photogrpaher. I was surprised to learn about this, though I can't recall where I read that. By and large settings that are applied to in camera JPGs are not applied to RAW data though, although certain settings that can be torned off or on can modifiy the RAW data such as highlight compression or automatic HDR adjustments such as found on the Canon G12.

 

[2F/2F]

So does it adjust exposure that reaches the sensor?

Edit, duh. Misread your post the first try.

Hi, Mark.

It doesn't adjust it once the shot has been taken, but it affects your meter reading while shooting. Just like -EC, or uprating transparency film. Your meter needle will point down the middle, but the shot will actually be underexposed. That means that if the Active D-lighting is turned off, and the composition, shutter, aperture, and ISO are kept the same, the needle will no longer point down the middle, but will be on the "-" side of the scale.

Same thing many people do manually in contrasty light, but built in, so you can read your meter directly. Personally, I think it only makes since to use it on Auto mode. Going into the menu and manually choosing Low, Medium, or High is exactly the same as manually underexposing either a little, a little more, or even more than that, and it takes much more time and effort than simply clicking your shutter speed faster or your aperture smaller without ever lowering the camera from your eye. The only benefit setting it manually if shooting raw would have would be the automatic boosting of the low tones by the corresponding amount of underexposure in your raw converter; and I believe that would only happen if using Nikon software. If using Adobe Camera Raw, the equivalent would be manually increasing the amount of Fill Light.

Of course, it makes a lot of sense to use it manually if shooting TIF or JPG, but the OP was talking about raw files specifically.

One great feature of the camera (and maybe a few other Nikons) is that you can assign custom controls to three different buttons on the camera; each of which can be made to control a plethora of features. I kept my DOF preview where it is, made the button below it an instantaneous spot meter, and set the AE/AF lock button to be the electronic level. Having the on-off spot meter there makes it really easy to place high tones in contrasty light, without actually having to flip the rear switch to spot mode and then back to CW-avg. or evaluative. It just takes a little experimentation to see how far above center to place something in order to hold texture or detail there. Having the electronic level there in a comfortable spot makes it easy and quick to level out a pic when shooting hand held. It is a very well designed and user friendly camera, without a lot of fluff. And what fluff is there doesn't impede.

 

[2F/2F]

Nikon manipulates the data that gets written to the RAW file on some of their camera models. For example, in some cases sharpening is automatically applied without the control or intervention of the photogrpaher. I was surprised to learn about this, though I can't recall where I read that. By and large settings that are applied to in camera JPGs are not applied to RAW data though, although certain settings that can be torned off or on can modifiy the RAW data such as highlight compression or automatic HDR adjustments such as found on the Canon G12.

That is interesting. I did not know that. I would be interested to know which models do that, and what changes are made before the raw file is stored on the card.

Given the OP's high level of technical prowess, I am also wondering whether this is a genuine search for knowledge on his part, or just a way to start a discussion. That's not criticism, either way, Ralph – just curiosity.

 

[David A. Goldfarb]

Not a camera setting, but filtration. In theory we believe we can reproduce the effects of filters in software, but when you actually try to do it, it is not easy to duplicate the results exactly, and I think that is interesting.

Try setting the WB to daylight and shooting a landscape with a medium yellow or orange filter and then without, desaturate the filtered image, and then try to achieve the same B&W result with the unfiltered image and channel mixer, and it isn't so easy, I've found, without also starting to work with curves and other tools, and often the result with the filter is better. I'm not entirely sure why, but it may be that the glass is also filtering UV in a way that doesn't happen when you try to adjust with software alone, and also I think the compensation for exposure when metering through the filter has an important effect. You can even test this with an iPhone.

Filtering for white balance also sometimes works better than adjusting in software, surprisingly. On the one hand, it's convenient to be able to adjust the RAW file later on a calibrated monitor and not to have to carry color conversion filters and not to be adding filters to the optical path, but it's worth comparing results with, say, the camera set to daylight and daylight fluorescent lighting and an FLD filter and maybe a slight adjustment in software to get it exactly neutral, and using software alone with no filtration to get the same white balance.

 

[RalphLambrecht]

Nikon manipulates the data that gets written to the RAW file on some of their camera models. For example, in some cases sharpening is automatically applied without the control or intervention of the photogrpaher. I was surprised to learn about this, though I can't recall where I read that. ...

That's my understanding too. Camera manufacturers try to compensate for the softening of Moir filters by adding automatic sharpening without user intervention, because they feel that it is a processing step and in a way part of the Moir filtering.

In fact, I don't believe that raw files are as raw as we are made to believe, hence my question. On the other hand, some raw conversion is probably very useful. A straight 'raw' file is most likely not very pretty to look at. It needs some gamma correction and so on to be useful to people who are not image software engineers. But it would be nice to understand what all is modified, how and why.

 

[donbga]

That's my understanding too. Camera manufacturers try to compensate for the softening of Moir filters by adding automatic sharpening without user intervention, because they feel that it is a processing step and in a way part of the Moir filtering.

You are reaching a conclusion that isn't generally true. One of the reasons for camera sensors having an AA filter is to eliminate the Moire pattern which tends to soften the image (the AA filter that is).

For example the Leica M9 doesn't have an AA filter which results in RAW files that may have Moire patterns. This can be easily removed in post processing. The effect of not having the AA over sensor receptors results in a much sharper image. I recently looked at a 24x36 inch print made by an M9 that looked like it was made with a LF camera. Of course using Leica lenses help as well.

As I said in my first reply I've only heard about Nikon sharpening RAW images on some models automatically. I'm not sure why they do this but it's probably not a bad thing since they are doing it to begin with.

Let's also not forget about the effects, good or bad, that specific RAW processing software has on the rendered image. In fact there is no image in a RAW file (not counting the small JPG that is often included in the file which is used to preview the image to the photographer at exposure time.)

What ever internal image processing camera makers and RAW software makers do, they do. And these days it usually results in excellent output or at least most of the time. But color film photography was never perfect either nor absolutely predictable, especailly in critical color reproduction applications.

 

[RalphLambrecht]

You are reaching a conclusion that isn't generally true. ...

None of my statements are generally true!
Photography has too many exceptions for that.

 

[markbarendt]

Nikon manipulates the data that gets written to the RAW file on some of their camera models. For example, in some cases sharpening is automatically applied without the control or intervention of the photogrpaher. I was surprised to learn about this, though I can't recall where I read that. By and large settings that are applied to in camera JPGs are not applied to RAW data though, although certain settings that can be torned off or on can modifiy the RAW data such as highlight compression or automatic HDR adjustments such as found on the Canon G12.

I'd be interested to know the source here.

I do know that Nikon's software, like Capture NX, can/will/would typically read more of the instruction set that the Nikon cameras write to their files. The default in NX is to apply all the camera settings, camera nef's & jpeg's are nearly indistinguishable when viewed with NX.

Adobe, in contrast, only reads part of the instruction set and applies it's own or user defined defaults/presets so RAW files display differently than camera jpeg's in LR and PS.

This was driven originally by a licensing/copyright/patent tiff between Nikon and Adobe.

It is not a one way is better than the other thing, just the way it is or was.

I don't know if that tiff was ever resolved legally or technically.

That tiff combined with a lot of wishful thinking and mis-understandings about RAW and it's workings have spawned lots of urban legends and conjecture.

 

[markbarendt]

Hi, Mark.

It doesn't adjust it once the shot has been taken, but it affects your meter reading while shooting.

That's what I was thinking.

The programable control that I like the most is actually getting to set focus exclusively with my thumb on the back of the camera "AF on" which frees up the half-push of the trigger to lock exposure.

 

[2F/2F]

That's what I was thinking.

The programable control that I like the most is actually getting to set focus exclusively with my thumb on the back of the camera "AF on" which frees up the half-push of the trigger to lock exposure.

Hi,

I cannot stand having AF connected to the shutter. When I shoot with AF (and I only do it with two cameras: Canon EOS 3 and 10D), I want AF to be a motorized version of manual focus, and nothing more. I want the same exact thought process I use when shooting manual focus: pick a thing to focus on, and then focus on it. With AF, I just want the camera to do the busy work of actually moving the elements for me, because it is less error prone while focusing quickly. This means I use a single AF point and a dedicated "focus" button, in all cases. I never have my AF set any other way. Having one button do more than one thing is an annoyance and an impediment to me when shooting.

But this is not a unique feature, being able to remove the AF command from the shutter button. Canons have had it since before they made digital SLRs, and I assume Nikons have as well. It really ought to be the default, though, at least on "professional" models.

However, with all this talk about AF, I don't use the D700 with AF lenses. It's the main draw of the camera in the first place IMO: no need to buy new, expensive, shoddily-built lenses for it. You can just thrown the old, inexpensive, well-built, reliable lenses on it, and they feel and look just like they do on a film camera.

The only thing my shutter button does is fire the shot...just the way I like it. I love Nikon digitals because they really feel like plain-old cameras, not like "Digital Cameras." I spend almost no time at all mashing buttons in the menus. My thought process is pretty much exactly what it is when shooting film. It's seamless. I turn the screen on only to 1) format my cards, 2) choose different non-CPU lenses, and 3) turn the grid lines on or off, or 4) look at histograms or show pix to people. And since the meter and the Auto Active D-lighting are so good, number 4 is rarely necessary.

 

[markbarendt]

I originally found the AF on method on an F100 that I had years back, really regret selling that camera. Used that setting on my D200 ever since. That is about the only feature that my N90s's lack.

That isn't much of an issue though because most of the glass I really like using is manual focus, 35mm f/2 Nikkor-o, 105mm f/2.5 Gauss, and 50mm f/1.4.

Being able to use the lenses for digital and film and to mix and match bodies to lenses is great.