RAW capture and processing: exposing to the right

Nice link. I used to ETTR with my GH2 and it did help me to better control the noise. I set the camera up so that it showed a short preview picture with "blinkies" turned on and from previous experiments with Photoshop RAW I got to know what level of "blinkies" I could recover in processing. I've yet to try out similar experiments with my 5N or GRDIV - must get around to testing them out.

Something else I'm curious to explore is adjusting contrast, sharpness and saturation in camera and seeing just how much they affect the raw file..
 
hmm
I've been struggling to "get" this technique since I first got my E-P2 and have read a few articles ... I think I'm finally getting there.
I liked this chap's style, although I found his English a little confusing occasionally (although I'll criticise properly when my Finnish is as good ) ... plus his E-P2 seems to have settings mine doesn't?
 
hmm
I've been struggling to "get" this technique since I first got my E-P2 and have read a few articles ... I think I'm finally getting there.
I liked this chap's style, although I found his English a little confusing occasionally (although I'll criticise properly when my Finnish is as good ) ... plus his E-P2 seems to have settings mine doesn't?

Paul I think he started out with the EP-2 but writes this article from the perspective of his EP-3. Could be wrong but that's the impression I get from his opening preamble.

Nice link. I used to ETTR with my GH2 and it did help me to better control the noise. I set the camera up so that it showed a short preview picture with "blinkies" turned on and from previous experiments with Photoshop RAW I got to know what level of "blinkies" I could recover in processing. I've yet to try out similar experiments with my 5N or GRDIV - must get around to testing them out.

Something else I'm curious to explore is adjusting contrast, sharpness and saturation in camera and seeing just how much they affect the raw file..
Thanks for the blinkies tip Norman. Let us know how you get on with the adjusting your contrast, sharpness and saturation in camera. I would have thought this shouldn't have any affect on the RAW file, but be very curious to know if your results yield anything different....as this would open the doors to another world of in-camera micro-adjustment, and possibly more latitude with the ultimate RAW files.
 
He gives E-p2 settings first then goes onto discuss how he works it on the E-P3 ... maybe I'll drop him a line for clarification
 
The noise reduction example doesn't really add up for me. If he can afford to hand-hold the ETTR image at 1/15 sec using ISO 1600, why does the non-ETTR image need a shutter speed of 1/50? Surely it could be shot at 1/15 and ISO 400 which would dramatically change the noise levels (certainly on a 12MP m4/3 camera!). The theory appears correct: less noise for equal ISO values, but in practical terms you can use lower ISOs when you aren't over-exposing anyway.

I can only really see the technique working for images which don't have a large variance in exposure across the frame i.e. where you CAN overexpose without seriously clipping highlights.
 
The most interesting thing for me was the emphasis he put on the camera histogram not being a true reflection of the raw data ... never seen that stated before in ETTR articles, and I wondered if it was definitively true for all cameras ...
 
^ I've read it before (it's been mentioned in several articles on luminous landscape), and I believe it is true for my EX1 although I haven't tested it specifically.

I must say I've started using the image on the screen more than the histogram to judge my exposure, since the histogram disappears as soon as I start dialing in exposure compensation, so I'd be going into EV comp, dial in a bit, go out of EV comp to see the histogram, possibly go back to adjust more, see if it was enough again... well you get the picture, it's a PITA. Only in manual mode is the histogram displayed at all times.

The way I understand ETTR, it's not so much about noise control but more about giving you (even) more options to get a contrasty scene than a normally exposed raw file does.
If the image data is bunched up relatively tightly in the tone-rich higher stops, you can apply a steep contrast curve without any banding or sudden tonal transitions: in a 12-bit sensor, like the article says the lightest stop has 2048 possible values and the darkest stop has 2 possible values. Already the 9th lightest stop has only 16 possible values.

Therefore, if you have a 6-stop scene exposed right around the middle of the tone curve, the darkest stop in this scene falls into this band with only 16 possible tonal values. Even if you adjust the exposure in post-processing to stretch the 6-stop scene to go from pure black to pure white (drastically increasing contrast), all the data in the darkest stop will still be divided over only 16 tonal values, giving very abrupt transitions or banding (and lots of noise). If you had exposed to the right, the darkest stop in your scene would have 64 possible tonal values, giving a much smoother look if you apply the same strong contrast.
 
The noise reduction example doesn't really add up for me. If he can afford to hand-hold the ETTR image at 1/15 sec using ISO 1600, why does the non-ETTR image need a shutter speed of 1/50? Surely it could be shot at 1/15 and ISO 400 which would dramatically change the noise levels (certainly on a 12MP m4/3 camera!). The theory appears correct: less noise for equal ISO values, but in practical terms you can use lower ISOs when you aren't over-exposing anyway.

I can only really see the technique working for images which don't have a large variance in exposure across the frame i.e. where you CAN overexpose without seriously clipping highlights.

Funny I also wrote the same concern on that blog link. The technique to me is really not holding much benefit to acheive the lower noise at higher ISO, specially when ISO is increased for quick exposures (freeze motion, hand-shake reduction etc) however it can be used even on very low ISO or base ISOs to reduce noise in latest M4/3 where base ISO is already high (starting 200 in some case) AND specially where you are not already worried for blown-up highlights, again mostly in Oly Pen sensors.

So in nutshell I would only use ETTR when light is mostly uniform accross the frame and I have enough available light to get more exposure for intended subject and I want to get still better contrast and safeguard for my post-processing recovery.

Otherwise there were many times I even went for ETTL =]] and leave the noise to be picked later in PP :p
 
Thanks for the blinkies tip Norman. Let us know how you get on with the adjusting your contrast, sharpness and saturation in camera. I would have thought this shouldn't have any affect on the RAW file, but be very curious to know if your results yield anything different....as this would open the doors to another world of in-camera micro-adjustment, and possibly more latitude with the ultimate RAW files.

Your right, I tried numerous combinations and shot the same scene - all pictures looked the same! So I guess these adjustments are purely for your previewing pleasure only.
 
Using a spotmeter

Here is the most recent LL article on this subject.

I first became aware of the article quoted by olli some time ago. With some nice cloud formations today I decided to use my Sekonic L-508 spotmeter and then manually set the exposure on my GF1 with the data obtained from the spotmeter which was set to the same iso as the camera.

I metered the whitest area of the cloud that I could locate and then dark shadows, getting the meter to then average the readings. I also tested the incident lightmeter feature with the Sekonic. However I found that the best method was to take the highlight reading and then reduce that exposure value by 2.5 stops. Any more and I started to get burnt out areas, although usually slight, in the image. Often the average reading and the incident reading above also resulted in the brightest areas beginning to burn out, in other words the average reading resulted in the highlights being placed just beyond the peak of the tone curve for the Panasonic sensor.

I then used curves to try and slightly lift the shadow values, detail had been recorded in the shadows but too much lifting of the shadows would result in some posterisation of the shadows.

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All taken using a Panasonic GF1 with Voigtlander 15mm f/4.5 Super Wide-Heliar lens, exposure settings derived from data obtained using Sekonic L-508 Zoom Master

Barrie
 
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