I got a 30D and I want to learn to expose my photos well. I read all about spot metering and I understand the theory and the idea.
I just don't understand exactly how to do it in real life. Could someone give me step-by-step instructions on what I would do to spot meter a picture?
Let's say I want to take a picture of a white egret in a dark lake. I want to expose correctly for the bird, not the water. So what exactly do I do?
I need practical advice on how to actually do this.
SPOT metering works best when you have something in the image that is 18% grey toned to spot meter, and which is big enough to more than fill the spot mettering circle or that you can zoom into to meter
Now to your question:
I don't know the right answer but this is how I would do it:
I wouldn't use the spot metering in that situation,(unless it was in a different light to me and I couldn't use incident readings) but if I had to I would either zoom in real tight on the whitest bit of the feathered friend (not it's eye or beak) and note that reading, and open up 2 stops, Same technique as for shooting snow scenes and white beaches; or I would zoom right in on the face , esp. eyes and beak and provided it was averagely mid toned would just use exactly that exposure setting
What I would do if I didn't have to use spot is to use partial metering ( spot might be swayed by sweat reflection highlights)and get an incident reading off my palm
I.e. get a reading of the same light that is falling on the bird [an 'incident' reading] and so I'd meter the palm of my (caucasion) hand in the same light as is falling on the subject and open up one stop, or as I have a 18% grey card in my bag exactly for this sort of situation I would meter off that. That really is the simplest slution to the scenario you describe
If the bird is moving in and out of shade this is a tricky on ebut you could try to use exposure compensation (EC) combined with a spot reading, i.e , take a spot reading of beaky at the approximate framing you want, adjust for correct exposure using EC, and make sure you spot read before firing
When is it best to use spot metering?
Get and read a good book on the 'Zone System' first written about by Ansel Adams
Basically you need to be able to visualise and recognise a tone and then meter to place that tone where you want it within the latitude of the film.e.g you may decide you want the birds feathers to be pure white with just visible detail. As has already been mentioned this will be at about 2 stops above 18% grey. Whereas if you were shooting a football game and the players were wearing grey shirts you could spot meter off the shirts and keep that reading to use without altering
As has already been mentioned by other posters most people use one or two methods or a combination of both for the situation you describe , which is after all probably the hardest to meter (but just try evaluative metering for that scene - you might be surprised!)
1- GET AN 18% GREY CARD
2 -meter off the palm of you hand and open up one stop (if caucasion, if not metter off the palm of your hand and compare to an 18% grey card so you will always know how much to adjst the reading when out in the field. make sure the sun isn't being reflected directly back into the lens off your hand, you want to meter the light falling on your hand not how much it can reflect back into the lens especialy if sweaty )
3- metter off lush grass. As long as it is fresh healthy lush grass it will probbaly be pretty close to 18% gey tone. Dry grass or old grass needs opening up by one stop approx (experiment)
4- meter off the darkest bit of a completely cloudless sky opposite the sun ( without polariser) [DON'T POINT ANYWHERE NEAR THE SUN OBVIOUSLY, UNLESS YOU WANT TO GO BLIND]
5- meter off a tarmaced road provided it is around mid gery not too dark or light
6- meter off anything else that looks mid grey toned (a wall, rusty metal, tree etc)
Exposure tip: When shooting people against the light (distinctly backlit) and the framing is bigger than a portrait, spot meter some shaded skin (Caucasian), and manually expose at the indicated (center null) value. The scene will then record in best balance. Open up one stop only for a tight portrait.
Just thought I'd mention that link - lots of useful stuff there!