Light metering HELP please!

AshleyKent

AshleyKent

Messages
400
Name
Ashley
Edit My Images
Yes
right i know how to take a picture <<<< this makes me laugh writing this

but can someone explain the different types of metering and why id use them.

EG... spot metering

any help would be appriciated.
 
You have all that equipment, and yet don't know about metering? :thinking:

The manual should explain each type of metering mode.
 
Spot metering: The meter reading is taken from a small spot, usually from the centre of the frame but on higher end models can be combined with the focus point. Usually this would be used by someone who is aware of what tone he is metering and where he wants it to fall on the tonal scale in the final image.

Matrix metering: This would typically be used for most other shooting. The whole area of the focussing screen is typically used and split into a number of areas, these readings from all these areas are averaged out to give a reading. On higher end cameras this metering can be combined with a sensor.which will then identify the orientation of the camera and have an algorithm installed to inform the processor where the sky would be and to allow for that when averaging. This is the best metering to use for general walk about photography.

Centre weighted metering: This is the precessor to matrix metering, it was done by having two meter cells one each side of the prism box and their area of cover merged in the centre. This was superseded by matrix metering when processors became more prevalent in cameras.

Averaging. This was the original TTL metering and used a sensor to measure the amount of light coming into the prism. Easily fooled by 'non-average' lighting situations and images with very bright or very dark areas. Rarely used in Digital Cameras but is what is used in a reflected light light meter.
 
Last edited:
EdBray said:
Spot metering: The meter reading is taken from a small spot, usually from the centre of the frame but on higher end models can be combined with the focus point. Usually this would be used by someone who is aware of what tone he is metering and where he wants it to fall on the tonal scale in the final image.

Matrix metering: This would typically be used for most other shooting. The whole area of the focussing screen is typically used and split into a number of areas, these readings from all these areas are averaged out to give a reading. On higher end cameras this metering can be combined with a sensor.which will then identify the orientation of the camera and have an algorithm installed to inform the processor where the sky would be and to allow for that when averaging. This is the best metering to use for general walk about photography.

Centre weighted metering: This is the precessor to matrix metering, it was done by having two meter cells one each side of the prism box and their area of cover merged in the centre. This was superseded by matrix metering when processors became more prevalent in cameras.

Averaging. This was the original TTL metering and used a sensor to measure the amount of light coming into the prism. Easily fooled by 'non-average' lighting situations and images with very bright or very dark areas. Rarely used in Digital Cameras but is what is used in a reflected light light meter.
Click to expand...

wow thanks for the reply... does metering make a difference when shooting in full manaul with the 5DII
 
AshleyKent said:
wow thanks for the reply... does metering make a difference when shooting in full manaul with the 5DII
Click to expand...

If you 'know what you are doing' then the use of spot metering in full manual and selecting the important tone that you want 'perfect' and you understand how to adjust the exposure to put that tone where it needs to be in the final image then yes the metering mode you choose will make a difference, but if you do not know then it probably will either not make a difference or make things worse.

Important tones:

Skin: very Black -1 to -1.5 stops, Black -2/3rds to -1 stop, Asian 0 (as reading), Caucasian +1/2 to +2/3rds stops, Albino +1 to +1 1/3 stops.

Other Tones: Green Grass, Blue Sky (90 degrees to sun), Red Pillar Box, Light Tarmac All as metered.

Then there are the 2 most important tones:

The brightest part of the image in which you wish to retain texture +2 to +2.5 stops.

The darkest part of the image in which you wish to retain texture -2 to -2.5 stops.

Read this:
 
EdBray said:
If you 'know what you are doing' then the use of spot metering in full manual and selecting the important tone that you want 'perfect' and you understand how to adjust the exposure to put that tone where it needs to be in the final image then yes the metering mode you choose will make a difference, but if you do not know then it probably will either not make a difference or make things worse.

Important tones:

Skin: very Black -1 to -1.5 stops, Black -2/3rds to -1 stop, Asian 0 (as reading), Caucasian +1/2 to +2/3rds stops, Albino +1 to +1 1/3 stops.

Other Tones: Green Grass, Blue Sky (90 degrees to sun), Red Pillar Box, Light Tarmac All as metered.

Then there are the 2 most important tones:

The brightest part of the image in which you wish to retain texture +2 to +2.5 stops.

The darkest part of the image in which you wish to retain texture -2 to -2.5 stops.

Read this:
Click to expand...

right im no expert but now im confused haha. will have to read up on general basics i reckon :D... thanks though

Scarecrow said:
Only if you are relying on what the camera meter is telling you when you decide on what settings to use.
Click to expand...

okay so your saying the metering mode tells you the exposure on the bar on the camera... if i change the metering the exposure bar will change different.. i think i know what i mean. haha

WillyB said:
Why, does he have to learn all about it before he buys anything?
Click to expand...

if you learnt before you buy then you wouldnt be better... get the equipment and then self teach :) thats what ive done and im not complaining... just want to learn more about photography and better myself. this is why the question was asked :P
 
AshleyKent said:
right im no expert but now im confused haha. will have to read up on general basics i reckon :D... thanks though
Click to expand...

The most important thing you can learn is how to expose correctly.

The camera's meter does not know what you are aiming it at, it is calibrated against 12% reflectance so it always thinks it is looking at a subject with 12% reflectance.

If you point it at something brighter or darker than 12% reflectance it will under or overexpose the subject.

Whilst spotmetering, if you point the camera at a tyre of a car and make no adjustment to the reading obtained, the tyre will come out grey and everything brighter than black will be overexposed! If on the other hand, you take that same reading from the tyre and then adjust your exposure by -2 stops (making the aperture smaller, selecting a faster shutter speed or lowering the ISO or any combination of those) then the tyre will come out almost black and the other tones should be correctly exposed.

In this case above you have selected your tone (Very dark but with some texture), know where you expect it to fall on the tonal scale (next to black)and made an adjustment to the exposure to place it there (all other tone will fall into place).
 
You must log in or register to reply here.
Back
Top