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This afternoon, I wanted to undertake a bit of an impromptu project down at St Leonards Park (where North Sydney Oval is) to try to catch the afternoon light with only the 20mm lens.

I bracketed like crazy and had a lot of trouble trying to merge different exposures of the same shot to get better exposure in the foreground (relevant for shot no 3).

I wasn't happy with the results, but would appreciate C&C.

This first one was actually an accident.





The use of the erasure tool in this one was pretty ordinary.





One thing I want to know is the techniques you use to get a well exposed foreground and background (sky) when there is something like 3-4 stops of difference between the two.

Cheers

P

Reschsmooth wrote:One thing I want to know is the techniques you use to get a well exposed foreground and background (sky) when there is something like 3-4 stops of difference between the two.

3-4 stops shouldn't be an issue. IIRC, most digital SLR sensors have a 6+ stop range (more than chromes, less than negs).

This gives me an idea for a nice rainy-day project: shoot a gray-patch strip and see what the real dynamic range in the RAW file is...

Cheers
Steffen.

Steffen, it is very likely I am missing something basic, but when the shot is exposed for the foreground (say the trees in shot 3), the sky is totally blown.

I tried masking and using layers of differently exposed shots, and I couldn't get a decent result (again, as per shot 3).

P

Reschsmooth wrote:Steffen, it is very likely I am missing something basic, but when the shot is exposed for the foreground (say the trees in shot 3), the sky is totally blown.

I tried masking and using layers of differently exposed shots, and I couldn't get a decent result (again, as per shot 3).

P

If you expose for an image part that lies on either extreme of the range you'll lose out on the opposite end. Properly exposing that part means putting it in the middle of the histogram.

In theory, putting the darkest and lightest part of the image at the extreme ends of the histogram should get everything important captured. The rest is curves work. Unfortunately, with digital you lose a lot of numeric precision on the dark end, which limits your ability to amplify dark parts of the image (you get posterisation). For that reason, you shouldn't expose anything important below the left quarter of the histogram, or lose the ability to lighten it up. Therefore, I guess your 3-4 stops are the practical limit after all

Cheers
Steffen.

Wow, Steffen, that actually made sense to me! I guess I have to learn how to expose the extremes properly. But thanks for the explanation.

P

Pat,

Following what Steffen said, on the practical manner.

On your D200, you can have your setting bank for "scenery" on your custom FUNC button set to "spot meter". Each time you use this along with a default set matrix meter, you simply have to press hold the FUNC button and it will turn itself into spot metering mode, very handy for these tricky sceneries.

Take the normal matrix metering, then press and spot meter the brightest area. You should read +2.0 or +1.5, depending on your purpose and scene, then take spot meter of your darkest shadow, should now read -2.0 or -1.5. Back now to your 'subject' and it should read +/- 0.3 EV. If you have got this, snap away and your exposure will be simply near picture perfect.

Tho if the spot meter is reading too far out EV that it can show, you will have to sacrifice either the shadow (totally black) or highlights (blown outs). PS. You will need to be in manual mode to do this.

Thanks Yi-p. I will give it a go.

Cheers

P