What exactly is spot metering good for?

[clkgtr37]

I have been reading many forms on metering with Canons compared to Nikons, and all of them praise Canon. Why you ask? Not because it is a far superior camera in every aspect, but because it has spot metering. I have been getting pretty decent with all the functions of my D30, but one that still escapes me is spot metering, when do I use it and what do I meter off when using it?

[Pekka]

Spot metering merely reads a smaller area than other modes. This way you can tell what exposure a certain highlight (e.g. forehead, nose) will require and if you check shadows and highlights you can determine the wideness of the exposure (dynamic range) and decide what part to capture from it if you can't capture it all. Spot metering is also useful when using a small white or gray card for exposure desicions - it's reading does not "bleed" false info in.

[Ken Fong]

I'm new at digital photography and just learned a very helpful technique in class that uses the spot meter. The D30/60 does not have a spot meter, but rather, a 'partial meter', which is slightly larger than 'spot' (9% of the total area)...for most purposes, it's the same.

I've been using the partial meter to make composite images...the same picture taken twice: one with the meter in the shadows, the other with the meter in the highlights. Using photoshop to combine the two, you achieve a photo that you cannot capture in one shot (you will see the details in both the shadows and in the highlights...nothing will get blown out.) John Paul Caponigro's book "Adobe Photoshop Master Class" touches this technique fairly well. Great for shooting mountains and sunsets...any subject where the light levels span a wide range and you want to capture all the detail...but it only seems to work if you have 2-3 areas of contrast in your photo at most.

Autobracketing does something similar, but you have less control over what you want to meter...but it seems to be a quick and dirty way to capture more data upfront (a wider span of light and detail), which seems to be the key in digital imaging.

Of course, I'm open to more suggestions (or correction) from experienced photographers.

[formal]

Spot metering can be used with the "Zone System" for exposure control. This system was designed by Ansel Adams for black & white film photography, but can be adapted to digital photography. Spot metering is not absolutely necessary, but it makes the system a bit easir to use.

The Zone System is relatively easy to understand and I have used it with a Minolta Dimage 5 (which has spot metering). You can use it with partial metering on the D30/60, but since the basic idea is to meter a single tone in the original scene, the bigger area of the D30/60 makes it a bit more difficult - you need a longer focal length or move closer.

David