Best capture technhique and processing tools ?

[Marpel]

Hmmm, interesting. I wonder if the quality gain made in ETTR for a jpeg is so minimal (comparing an 8 bit 256 level jpeg to a 12 bit 4096 level Raw as an example - using the math that is used in the LL article, the brightest f-stop of a jpeg is 1/2 of 256, or 128, whilst the 12 bit equals 2048) that the subsequent processing of the jpeg to "bring down" the exposure negates the benefit or even causes more damage (layman's term) than is worth the effort. As Dieter suggested, perhaps a real world comparison of images is in order.

Doug, I, like you, made some assumptions, with one being that ETTR was of value only for Raw files. This assumption was made after reading the Michael Reichmann article, in particular his comment under the caveat heading. At the time, I actually wondered if he was making that comment because he only/mainly shoots Raw and hadn't done any testing with ETTR and jpegs, so the article was only about Raw, or he (or others) had done testing and discovered ETTR gives greater benefit to Raw over jpeg (with still some benefit to jpeg), or he (or others) had done testing and discovered ETTR is only for Raw and is of no benefit to jpeg. I re-read the caveat a couple times and, as it seemed to be quite specifically worded, assumed that he meant the latter. Perhaps I will go on that forum and ask for clarification.

Den, I am curious why you suggest two camera exposure methods for ETTR - one for jpeg and the other for Raw. Wouldn't method 1 work just as well for both (once you figure out how much compensation is necessary to reach just below the highlight clipping point, with a bit of headroom, for your particular camera)?

Marv

[den]

Marv...

Den, I am curious why you suggest two camera exposure methods for ETTR - one for jpeg and the other for Raw. Wouldn't method 1 work just as well for both (once you figure out how much compensation is necessary to reach just below the highlight clipping point, with a bit of headroom, for your particular camera)?

Short answer: Yes... but... (and the long one...)

...In order to implement a preset "'Spot" +2EV Compensation', you must:
(1) change the camera meter mode from 'Evaluative - Multi-zone' to 'Spot'...
(2) center 'spot AF' on the scene's in-frame whitest spot and lock the AE... ...perhaps a cloud edge 'high' highlight...
(3) compose and AF on the scene's main visual element... ...perhaps the 'eagle' sitting on the branch that you had sighted took flight while you doing (1) and (2)... ...ugh!!!!
(4) repeat (2) and (3) for each in-frame composition... ...not easily done when rapid frame sequences are needed... perhaps the 'eagle' in take-off with wings spread grabbing air and talons extended.

Also, the LL author was making a point that ETTR could easily be done if the in-camera processers were modified by manufacturers and that manufacturers are perhaps using outdated 'film' methods for exposure settings/calculations for the modern current-day digital cameras... and also that ETTR of a RAW file can/could be easily done post-camera with a RAW converter where the data is still linear... ...PWP5's RAW Dialog, for example.

Noise suppression aside... for my two camera's [Canon EOS-350D and PowerShot45], the "'Spot" +2EV Compensation' method will generally provide the better out-of-camera overall scene exposure, than 'evaluative or zone' metering as illustrated here: http://www.dl-c.com/discus/messages/2/3622.html, if the scene remains static for the set up. Note that the illustrations are for near full dynamic range landscape images with two main histogram peak sets separated by a minimum, one set for the sky and one set for the foreground. The top illustration is where the dark foreground comprises more than 50% of the scene and in the bottom illustration, the dark foreground comprises less than 50% of the scene... and that the "'Spot" +2EV Compensation' RGB histograms are much fuller [Equalized] in each case than the same scene compositions recorded with 'Evaluative - Multi-zone' metering.

[Marpel]

Thanks Den. I actually like those "long answers" as they help me better understand issues.

And for those who have participated in some of the preceding conversations, or are just wondering, I posted a question on LL about ETTR and jpeg images and, to date, have received two responses. Both are fairly short but I will provide some quotes which give you an idea:

"JPEG is a finished output format, never intended for post processing. So conceptually JPEG-ETTRing is crazy." and

"Jpegs are far from linear (gamma encoded, color space encoded, white balanced to name a few) The best you could do with Jpegs is to aim for precise exposure and correct white balance, not needing post processing, just as Guillermo said."

Marv

[tomczak]

At the risk of being ostracized, here is an image that Guillermo Luijk posted in one of the LL discussions on ETTR - I just couldn't help myself...:

http://www.luminous-landscape.com/forum ... ic=56863.0

[tomczak]

A link to a treatise on noise and bit depth - quite academic and thorough, but well written, I think; may address several question posted in this thread.

http://theory.uchicago.edu/~ejm/pix/20d ... index.html

[doug]

I just love the LL forum response, "JPEG is a finished output format, never intended for post processing."
What a dramatic contrast to Jonathan's use of a "Bird" JPEG in the tutorial that showcases his post processing software. LOL

Anyway, Marv. Thanks for going to the trouble to delve deeper into this issue. In the total scheme of things, it may not be particularly momentous. But the fact that digital photography captures exponentially more tonal information at one level of brightness than it does at another seems to me to be one of the most significant differences between it and the way that film (which I dealt with since the early 1970s) reacts to light. That curiosity, and its implications for selecting exposure, has intrigued me ever since I learned of it.

[Dieter Mayr]

Maciej, unfortunately i'm in lack of a black cat so you I just could take a pile of (char)coal as a example.
Setup is: Camera set to ISO1600 to get a good amount of noise to easily see a difference in S/N ratio.
Camera as a Fuji S9600 bridge, JPEG in maximum quality, quick and dirty tabletop setop, the coals placed on a piece of sheet metal (due to the mostly dirty nature of the coal in the quick and dirty setup I did not want to spoil a piece of textile or paper background, so the less optimal solution with the sheet metal.).

First a over all, resized picture:

DSCF3817.jpg (29.92 KiB) Viewed 4237 times

A 1:1 crop of a "correct" exposed image ( F 4.0, 1/15 sec.)

DSCF3817_1.jpg (45.49 KiB) Viewed 4237 times

A 1:1 crop of a "ETTR" exposed image, brightness shifted back to "correct" (F 4.0, 1/6 sec.)

DSCF3823.jpg (36.64 KiB) Viewed 4238 times

No other editing is done, just the shifting of brightness at the ETTR image and cropping.
I think it can be clearly seen that the noise is considerably lower.

[JvdW]

In the ETTR discussion I can only add from my personal experience that it does indeed depend on the subject. As a photographer I have to decide wether the highlights or the shadows are more important and expose accordingly to the right or the left (in most cases it is to the right)

About best capturing techniques I think it is worth to mention the use of filters.
As a landscape photographer I am often confronted with scenes that exceed the dynamic range of my camera. One way to deal with this is multiple exposure and software HDR stacking, but personally I don't like this aproach (the results can be beautifull, but I find it very difficult to get what I want whith HDR). Instead I make frequent use of neutral density graduated (NDG) filters placed before the lens to darken the sky during capturing. These filters help to make the dynamic range of the scene smaller, resulting in photographs with no (or less) blown highlights and more details in the shadows. (The ETTR decision remains the same of course)
Compared to HDR the NDG filters have the benefits of instant preview and no problems with moving objects. As the NDG filters have a linear gradient they are most useful for scenes with lighting from one direction (sky and sun in landscapes). For indoor photography whith local light sources and windows HDR is more versatile.
Another useful filter is the polarizer which effectively filters reflections from non metalic surfaces. In landscape photography this results in more saturated colors.