aborr wrote:
Wilt,
You make a good point in your spot metering example, but I think that what you're really showing is why it's often bad to rely on a camera's autoexposure system, regardless of the meter pattern selected.My strategy, most of the time, especially when shooting action, is to meter off an 'easy' target, like a patch of sunlit grass on a playing field, and then use that as the basis for manual exposure settings. That way you don't have to be concerned about the camera making bogus exposure changes for shots containing a changing mix of light and dark faces, light and dark team uniforms, etc.
I don't disagree with your bolded statement.
Having said that, my dislike for Evaluative is simply NOT KNOWING WHAT IT IS GOING TO DO is my major dislike of the mode! With Spot, I know what I am reading (and ignoring) and I know the fundamental tonaliity of the area that I am reading, so I know exactly what the reading tells me, and how that will show up in the exposure. With Evaluative, that gray card reading will expose differently under that backlight situation, and because I do not know the brightness difference of the surrounding zones to the focus zone, I do not know how much they will wrongly bias my reading.
IdahoBob wrote:
Question: Same cameras. Going to the Space Shuttle launch next week. Which metering should I use. Daytime launch. The rocket flames are incredibly bright. Will be 6 miles away, using the 1DIV and 800mm. Thoughts?
No metering. Read my photo advice, I have been only to a dozen or so launches. In short - meter as if you would before launch, then stop down by one stop.
Don't run out of buffer. Most people do. It moves rather slowly...
When I first got an SLR, I usually used evaluative and sometimes the spot mode. I don't know when I switched, but now I almost exclusively use centre weighted metering. I just know how it will react. I'm not perfect, but usually I can effectively judge the exposure of most scenes with this mode. Evaluative isn't quite as consistent for me because it's doing a little calculating, and I have not yet learned how to read its mind.
I use the chimp method: Shoot in Manual mode, glance at the meter (Evaluative),
shoot, check histogram and adjust. The next shot is pretty close to right on.
Obviously, I'm not shooting much where the scene changes quickly.
Ghost wrote:
There's a reason why there are different metering modes. There is no one "correct" mode. You select them based on the type of exposure you want.
Having said that, I almost virtually nearly 99% ever use evaluative/matrix.
+1.
Your mileage may vary as they say....
Spot/ Centre is generally no use when composing off centre, which do a fair bit.
For most people these modes are fine.
I generally use evaluative, take a shot, check the histogram and go from there.
stanj wrote:
...Besides, centerweighed is the only one that will keep adjusting during a burst. All other metering modes are locked in at the time of the first exposure for the duration of the burst. Not always a welcome thing.
Are you sure about that one Stan? I suppose it might be true if you're using the default half-press to activate AF; I don't know as it's been years since I've done that. But if you're using *, my recollection is that whether AE is locked or keeps cranking during the burst depend on your particular setting of CF4 or IV (depending on the body).
Truth of the matter is, all metering modes are good - effective and reliable. Different situations call for different metering modes. Checking the histogram and exposing to the right is always recommended. And LR-3 is an amazing tool for making exposure compensation and adjustments, and so is CS-5 I am sure.
stanj wrote:
I am all the way for center weighed. I am old school - can look at a scene and know how much EC I need to dial in, without the computer smarts coming in the way.
Besides, centerweighed is the only one that will keep adjusting during a burst. All other metering modes are locked in at the time of the first exposure for the duration of the burst. Not always a welcome thing.
+1!!
I use spot metering 99.9999% of the time. You know what the most important aspect of the shot is, you know if you want it to be a mid-tone, light-tone, or dark-tone, and that's all you can control. Everything else is relative and once you set it you're done.
As for center-weighting vs. averaging, my understanding of center-weighting is that the computer heavily weights the "reflective value" of discrete objects within the frame, while for averaging produces just what one might expect; an average of all elements within the frame.
PS - with spot, you can easily control how light or dark a subject is relative to the background (e.g., back-lighting situations), or when you deliberately want to blow something out or throw it into deep shadow. No EC setting is required because you know, in 1/10 of a second, how much to change the exposure either way.
I rarely, if ever, use EC settings. I do the calculation in my head and change my manual settings.
Sir_Loin wrote:
I was out and about today in the unseasonably warm weather for this time of year in Blighty and I was messing with different metering settings.
I found that I was getting more accurately exposed images with Centre-Weighted metering when there was a high dynamic range within the image. Evaluative metering tended to overexpose a little.
Which made me think, do other photographers change the metering under certain lighting conditions or just leave it set at one or the other all the time?
This was with both my 5D2 and 1D4 in case people were wondering what's this to do with Canon. ...Show more →
Hi Sir_Loin,
Well, it's a choice between neither for me...and I saw no point for casting a vote. It is an interesting discussion though, and I am enjoying reading about how other folks approach things! FWIW, my methods...
Now, I have experimented with the various metering modes that Canon offers since getting my first Digital Rebel, and the only time I purposely use on-camera metering metrics is when I'm purposely looking to create a more candid (read: P&S) look to my images...basically, when I'm looking to create snapshots. Then it's P mode with me enjoining the pop-up flash (with diffuser) at my discretion...yes, that's with the 300D and the 30D.
For my shooting enjoyment, there are those exposures that I seek out to create where I am in control of most parameters of what I am doing with the camera as in Av or Tv modes or all parameters as in M...my metering then is almost exclusively Spot with me deciding how I want my central point of interest to be exposed...and then there are snapshots, where I can free myself of exposure concerns and just have goofy fun behind the lens! And then all mistakes are happy ones...and they're welcome!
stanj wrote:
...Besides, centerweighed is the only one that will keep adjusting during a burst. All other metering modes are locked in at the time of the first exposure for the duration of the burst. Not always a welcome thing.
Nill Toulme wrote:
Are you sure about that one Stan? I suppose it might be true if you're using the default half-press to activate AF; I don't know as it's been years since I've done that. But if you're using *, my recollection is that whether AE is locked or keeps cranking during the burst depend on your particular setting of CF4 or IV (depending on the body).
Nill
I know this for a fact for my 1D series bodies. May have to do with my CFns, but that's the way it is. I use the shutter to focus, if it matters. I know real men use the * button.
I just double checked the EXIF data, and the 1D3, and 1D4, do adjust during a burst, so maybe take another look before you say you know for a fact.
Also there is nothing in the C.Fn's that has anything to do with the camera adjusting exposure or not. The simple fact is the camera will not give you an exposure that is wrong per the data is has in whatever mode it is in.
brede wrote:
...Also there is nothing in the C.Fn's that has anything to do with the camera adjusting exposure or not. ...
Well, actually...
C.Fn IV -1 Shutter button/AF-ON button
0: Metering + AF start
1: Metering + AF start/AF stop
Pressing the <AF-ON> button during AF will stop the AF operation.
2: Metering start/Meter + AF start
This is useful for subjects which keep moving and stopping repeatedly.
In the AI Servo AF mode, you can press the <AF-ON> button to
repeatedly start or stop the AI Servo AF operation. The exposure is set
at the moment the picture is taken. Thus, the optimum focusing and
exposure will always be achieved as you wait for the decisive moment.
3: AE lock/Metering + AF start
Convenient when you want to focus and meter at different parts of the
picture. Press the <AF-ON> button to meter
That's from the Mark IV instructions. There have been variations on this theme for every Canon DSLR body I've owned going back at least to the 20D and original 1D, CF IV in the later bodies, CF4 in the earlier ones (the latter with respect to the function of the * button, as those bodies didn't have the AF-ON button).
There are other CF's that affect metering as well, of course, but this is the one we're talking about in the specific context of locking the exposure for a burst or not.
As for:
...The simple fact is the camera will not give you an exposure that is wrong per the data is has in whatever mode it is in.
OK, I stand corrected, if you have it set to 3. Thank you.
But if you are holding the AF ON button while doing a burst with this setting the camera will adjust. My point was that it was said that only in a certain exposure mode will the camera adjust during a burst, which is not true.
And why during a burst would you want to take an image that isn't exposed correctly?
As for: ...The simple fact is the camera will not give you an exposure that is wrong per the data is has in whatever mode it is in. If only that were true. ;-)
Yeah would be nice, but the camera always thinks that it is right, even if to us it isn't.
And why during a burst would you want to take an image that isn't exposed correctly?
Because if the system reads the exposure as significantly changing during a 9fps burst, it's most likely making an automatonic error.
For instance, if I'm shooting football (either kind) and the system senses an exposure change during a single play, the most likely reason is that a preponderance of one team has entered the scene and the color of their uniforms appeared to the machine to be a change in scene brightness, or as I panned the camera the background changed from predominantly dark-toned bleacher crowd to predominantly light-toned sky.
There might have been a legitimate change in the quantity of light upon the subject, but in the course of a 9 fps burst, the most likely event is merely a change in the reflective values of the objects in the scene.
Yeah would be nice, but the camera always thinks that it is right, even if to us it isn't.
Someone else has already said, "A computer is always certain. It may be wrong, but it is always certain."
I tend to leave it on the setting that gives a new exposure reading for each frame, because I'm often tracking players in and out of sun and shadow in the daytime, or through the abominable cycle of a stadium light at night.
OTOH, one reason I can easily think of for wanting the exposure locked through the burst would be if you wanted the exposures to match, e.g., for a series.
Besides, "exposed correctly" is to a large extent a subjective judgment.
FWIW, my methods...