2010-02-07

Winter time, underexposure time

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As I browse through photos on Picasa Web, Flickr and who knows where else I can't help but notice that too many people trust their camera's automatic metering too much. This is especially problematic in winter - on overcast days it might be relatively gloomy, but nevertheless, the subject we're taking photos of are in fact brighter than average.

This leads to a lot of underexposed photos being showcased on the web - our perception is mislead by the dark and gloomy winter days, the camera's LCD can't be trusted anyway (except for the blinking highlight warning or histograms). Here's a JPEG directly out of my Fuji S5pro in Aperture priority mode:


Trees (auto) (FinePix S5Pro, 1/70s @ ISO 100; f/8, 116 mm DX)

On the dark background of the blog it might not immediately look too much underexposed - but it is (if you click on the photo you'll get a 912px wide version with a white border, just check how much the bright - foggy - sky differs from the plain white of that border). The problem is of course the camera's metering: it treats everything it "sees" as being 18% grey (which is about the same as reflecting 50% of the light) - but for a winter scene like this, it's clear that it is not 18% grey!

In situations like these, I set an exposure compensation of +1 stop (even though "they" always say that it is not necessary with matrix metering yada yada yada because this "intelligent" metering technique "knows" the scene...) and the result (again, JPEG straight out of my Fuji S5pro) looks like this:


Trees (+1) (FinePix S5Pro, 1/35s @ ISO 100; f/8, 116 mm DX)

Of course, you can simply adjust exposure in post processing. But that's lame, and the most important part of a correct exposure in the digital domain is: capture as much light as possible without blowing out the highlights (hmmmm, I think I should have this as a boilerplate to insert into every other blogpost:-) because the right side of the histogram (the lights!) contains more detail!

And that of course means: the photo contains more data to work with in post processing. JPEGs with their limited bit depth will benefit from that a lot if you need to post process them (but in reality of course - here's my other boilerplate - you should shoot raw all the time).

Both of these photos where taken with the 70-300VR lens with the camera on my Giotto's 9970 monopod with Manfrotto RC234 tilt head. They are not exactly pieces of art, I just thought about this problem on my Sunday morning walk with Toni & Fuji and wanted to have illustrations. :-)

4 comments:

  1. Hi Alex! It's been a while that I noticed how my EOS 1000d exposure meter tends to underexposure to preserve details in light areas. Do I get it well? Inconsciously I should already knew that, because I always shot with -1 stop, but I have never taken photos in conditions of high lights just you did here. I should take notes! Thanks!
    By the way, a question.. how did you get the "TAGS CLOUD" and the pop-up of the photos???? :D
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  2. This is one thing that hasn't changed since the analogue metering of film cameras. Or has it? How should I know, I have such an old camera (Canon EOS D60, 2001). I learned this underexposure issue in the 80's from my father, who taught me to compensate exposure on snowy scene, and I still didn't compensate enough. Camera had the meter, I had the "matrix", and we both failed, LOL! Experience is easy to gain with digital cameras. But I still don't believe in matrix metering. Haven't seen the effect yet. Old cameras, old brain...

    Okay, I actually had one thing to say about exposure and correcting the exposure. Digital cameras do benefit from exposuring "to the right", that's clear. However, when you're developing your raw images, you can correct the exposure back, if needed, depending on the subject. Who said you must crank the levels all the way up, on every photo? For example, one morning I took some snowy landscape images, and if I corrected the exposure to the max, the authentic feel of the morning light was lost. "It was not that bright!". Thinkin about it now, if I had a tripod that morning, I could have had all the light I wanted, and the negative exposure correction would have made the photo look even better - less prominent noise in the final 8-bit JPG. But, I was riding my bike to work, it was -28C, the lens has enormous vignetting...

    P.S: The matrix has you!
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  3. It depends, Sami... if you want a photo right out of cam that looks realistic... go for JPEG and try to get the best "real life" exposure. If you want maximum details and dynamic range... then shoot raw and expose to the right. And read that article on LL that I linked (again;-).
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  4. yes, exposure to the right, and then process it to the left if needed. this is what i tried to say... thanks for the jpg tip, but no, i will not try jpg for the beautiful landscapes, or much anything, except for timelapse and some random documentary images that need to be forwarded quickly. how come i can't get capital letters? (using now opera mini beta)
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