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Controlling digital highlights

Paul L

coffee lounge for me
Rather than troll the Olympus Pen micro 4/3 thread I thought I would separate out the discussion (with Cliffpatte and Anex in that thread) about dynamic range and general digital struggle for me since giving up film.

You read a lot about poor dynamic range of digital plus sensors struggling in low light. Here's a shot of my daughter at her beloved weekend escape (low res 'Easycapture' file from 4mb jpeg which in turn is from 10mb ORF raw. I can link to a higher res file but assume it suffices to show the problem).



This shot is less overblown than most of them but is as good as I get and daughter's sleeve is not a white top, it is a fawn and blue striped top. I never used to get this problem with my 35mm slides. I have read that you should underexpose digital and then use software to recover. Streuth, surely not, what a ball-ache, especially checking after each frame when you are reeling off some shots unless you have to get through a learning curve to know what to expect.

So, how do you control the highlights with digital in a sensible manner?
 
Paul,

You do what you suggested - the shot you've posted has quite a bit of dark near the centre of the frame so the camera will probably use a centre-weighted exposure and mess this up by over-exposing. You can't recover the colours from over-exposure.

So, you either want to dial in some exposure compensation, or use a manual mode.

The idea that you should then recover something by munging the shot in software is wrong advice - the problem is simple, you need to get the exposure right when you take the shot and there is nothing else to do.

Personally I tend to use manual mode when conditions get difficult, take a test shot, check exposure on the screen, then adjust and use this setting for a number of shots. I shoot RAW which means I can drop the exposure a little in my raw processor if I get things wrong, but mostly I don't.

Cesare
 
I guess what I have found from the outset (Oly E510 14-42 and 50-150 4/3 lenses and now Zuiko 50mm 1.8 manual 45mm len being my first digital outing) is that shots I would not have expected to be difficult are in fact difficult.

With 35mm slide I would have confidently taken shots outdoors in sunshine. So, assuming I grey card, use a lightmeter or pick a skin tone or perhaps even grass for a reading would the shot be expected to expose okay or would the format (or individual sensor) struggle to streeeeetch from the dark and the light? I guess I need to take a lot of shots this summer and experiment.
 
I'd say it looks more down to the light. Your daughter's face has prominent shadows from the hat, and there's a strong shadow directly underneath the fence at the back. I think film would probably struggle too, and you'd print on less contrasty paper to improve things. The digital equivalent is to shoot raw and adjust in the 'developing' to jpeg.

I don't think the exposure is too far out, because the horse looks well exposed.

I don't think you ever get great shots unless the light is good, and if you have to work with what light there is, it's always a bit of a compromise.
 
Responses appreciated and food for thought. I reckon I leaned on my Nikon film set-up an awful lot and the slides, metering et al probably meant I did not have to think hard enough about the problems. I don't have my old slides scanned to show a comparison but don't think they struggled as much. It reminds me of my first SLR and proudly taking shots all the way around France only to find on return that shot after shot was flat. No shadows in the scenes, no impact to match the visual feasts I was trying to capture.
 
The camera has several modes built in that you get at via the menu system - you may be able to select a less contrasty mode. You can also under expose as suggested earlier. You could also get the camera to take a series of pictures with a different exposure - do this as part of the learning process to get to understand how the camera works.

Also what meter mode were you using - again experiment with the different modes.

In very contrasty light I often use fill in flash to even out the lighting and brighten up the shadows.
 
I have but I think it's only now that the questions are starting to form and I have no doubt filtered out solutions to problems I have not even been aware of. Our brains can be too good at that.
 
Hi Paul

I don't know what the option is on the Olympus system, but Nikon digital cameras (well the higher end ones) have a system called Active D-Lighting. If you enable this and shoot RAW you can use Nikon Capture NX to recover highlights or switch it back to as though you hadn't used it in the first place. Shooting 14bit RAW also helps by giving you a bandwidth of something like 3 stops over and 2 stops under whatever you shot originally.

See if you can find the Olympus equivalents and then try that.
 
So that's what 14 bit does. With monitors and printing allegedly showing only 8 bit you wonder why bother but the bandwidth sounds good. If pixel-pushing works the sensor harder then 10mp is more than enough. Wrotniak does talk about the E510 blowing out the highlights (when saying the E30 improves here even though that's working the sensor to 12mp) so I might just email him and se what he says to do. If the answer is get a better lens then fine, if it's use certain apertures or metering also fine. If it's asking too much for an action shot on a sunny day then I will start form scratch. In the meantime I will start bracketing shots, some or all of the issue will be me learning to work in a different set of compromises to those I previously learned to take in my stride.
 
Tried a few shots with the D50 last week, and couldn't believe how utterly crap the DR was compared to neg film. In normal subdued sunlight and with -1.00 exposure, everything was still blown to buggery. Even with faffing around with vignetting and variable filters in ACR, it still looked like shite. And it's not just the blown highlights, it's the fugly colours anywhere near the highlights that destroy the look.
 
Guy, if you want to shoot the odd digital shot, get yourself a 2nd hand Fuji S5 Pro. The extended dynamic range over the D50 is real.

Paul, 14bit adds principally to recovery of shading gradations in shadows. So to exploit this you would shoot typically at -1 ~ -1.7 EV and then use a RAW editor to recover the details. I leave my D700 in 14bit mode all the time and the D300 in 12bit mode as 14bit mode makes it a bit lethargic.

From what I have read about the E510 it probably errs on the side of overexposing by default so you might want to set it at -0.3EV as a default and then bump this to -1EV in bright sunlit shots. If you can auto-bracket you might want to pick -0.7EV and bracket +or - 0.3 around that figure - see how it works.

One advantage of always shooting slightly underexposed is that you get a shutter speed increase, but you need to adjust your workflow when processing the RAWs.
 
Guy,

I traded my Nikon D2H for a Fuji S5 a couple of years ago because of the advertised extended dynamic range and film-like colours. The first claim is true and second is true-ish.

Film is still film, but if you need an extra stop or two of latitude over your D50 and prefer the look of film the Fuji comes reasonably close for a digital camera. But it ain't a Rollei loaded with Fuji Pro 400H, and that seems to be your calling in life. Quite honestly, your D50 shots were good but you've hit a new zenith since you've framed the world in 6x6 squares.

Joe
 


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