Spot Metering, Exposure lock and the 5D

[hjoseph7]

<p>There got to be an easier way of doing this, yesterday I was trying to use spot metering to get the type of exposure I was looking for without relying on evaluative metering using my 5D.<br>

<br /> I was trying to take a picture of a model with a dark blue hat, her skin was tanned complexion, depending on what you consider tanned. I decided to use Spot Metering because I was not worried about the background, but I wanted the model face and her hat to be perfectly exposed. So this is what I did:<br>

<br /> I set the camera to 'P' and set the metering to spot metering.<br>

<br /> I then metered off the hat and underexposed by about 1 1/3 stops so that the dark blue hat would fall about a stop and half under middle gray. If I would have metered off the model's face then the dark blue hat would have come out slightly over exposed.<br>

<br /> OK then I realized something, because the spot meter is centered inside the viewfinder, the model was also centered, I would have to lock the exposure so that I could recompose the shot otherwise I would not be following the rule of thirds.<br /> OK so I lock the exposure, but now I had to re-focus on the model's face. The 5D does not have a AF button that I know off so I would have to use the shutter to re-focus again. This is while the AE is locked.<br>

<br /> The 5D gives you a wopping 4 seconds to re-compose the shot, focus and shoot before the AE lock cancels out.<br /> To make it worse none of the focusing points falls within the rule of thirds area, they are all concentrated around that small elipsis in the middle of the viewfinder ! That means you have to move the camera around until one of the focusing points lands on the model's face then hold the shutter until you are finished recomposing, then if you are lucky that your finger didn't slip off the shutter or the AE did not cancel out you can take the shot all within 4 seconds time ?<br>

<br />This is fine and dandy if you have all the time in the world, you have a very patient model, or you have very nimble fingers. I just can't imagine trying to do this in a very busy situation or on a tripod. You know what I think, maybe it's time that Canon remove the finance and marketing guys from the decision making process, then again it maybe it's me ?</p>

<p> </p>

[pbalko]

<p>There's a lot I don't understand about metering and exposure (most of it, really) but why didn't you just shoot in Manual: meter the hat, adjust shutter speed or aperture accordingly, focus on the face and shoot? What am I missing?</p>

[davebell]

<p>I've shot plenty of weddings with the original 5D. As long as you're not on top of your subject with a long lens and a wide aperture you can happily just use the centre focus point to focus and recompose.<br>

I generally use evluative metering. I judge the scene and knowing what I want to expose for, I increase or decrease the exposure accordingly. I shoot in a mixture of aperture priority and manual mode. These modes give me more control than P mode in which the camera decides everything for you.<br>

If I was to spot meter I would probably use manual for total control. Select an aperture and ISO and then adjust the shutter to get the reading you want, either centered or maybe 2/3 of a stop over, then recompose and shoot. All done in a couple of seconds max.</p>

[Marcus Ian]

<p>I use spot metering and center point AF for 99% of my work, and did so on the 5D before the 5D2. Generally, I am either shooting M or Av, so adjusting my exposure manually is simple (and fast).</p>

<p>Since the spot metering is only centered, it is fastest to decide what is to be properly exposed, test and lock your exposure, refocus as necesary, recompose and shoot. What I'm not sure I understand about the original description is why you would have P set your settings, and then manually set the exposure to -1 1/3 stops off 'neutral' then focus and recompose<em> instead</em> of simply using M to set the exposure at -1 1/3 of your 'spot' (the bar shows what your settings will result in for that spot) then focus and recompose. ... so much simpler... </p>

[scott_ferris]

<p>M mode and take some readings off the face, set Av and Tv and check histogram, make any adjustments, then spend the rest of your time shooting with the focus, recompose technique.</p>

<p>Why do some people make this so complicated?</p>

[morthcam]

<p><em>The 5D does not have a AF button that I know off so I would have to use the shutter to re-focus again.</em><br>

<em><br /></em><br>

Try CF4 and back button focus<em><br /></em></p>

[bradford_smith]

<p>+1 to what Matt said. This is the way I shoot all the time. CF4 with option 1 (AE lock/AF).</p>

[pmind]

<p>+2 for Matt...I've used that method for years with the 5D MkI</p>

[dan_south]

Harry, first make sure the your ISO is not set to Auto.

 

Put the camera into one of the auto exposure moves (P, Av, or Tv). I use Av exclusively when spot metering.

 

Make sure that Exposure Compansation is set to zero.

 

Spot meter something in the scene. Remember or write down the reading. Example: 1/60 @ f/8.

 

Make adjustments for the tonality. If you want what you metered to be one stop darker than 18 percent gray, for instance,

change your shutter speed from 1/60 to 1/125.

 

If the shutter speed is not adequate to freeze movement or camera shake, translate the exposure using the Reciprocity

Law. E.g. 1/125 @ f/8 = 1/250 @ f/5.6. (Alternately, you could have changed the shutter speed and the ISO setting and left the aperture at f/8.)

 

Switch the camera to Manual Exoosure (M) mode.

 

Dial in your calculated exposure. Example from above: 1/250 @ f/5.6

 

Shoot a frame.

 

Evaluate the results if you are using a digital camera. Adjust if necessary.

 

Shoot frame after frame knowing that your exposure will be correct unless the light changes, e.g. The sun comes out from

behind a cloud.

[hjoseph7]

<p>Thanks for the advice everybody, I'll try CF4 and see how that works, but wouldn't I be changing the AE lock to AF ? Then how would I lock the exposure before recomposing. Another thing in manual mode there is no AE lock, this goes for the 7D also. In Manual the metering needle will jumps all over the place so it is almost impossible to get a proper reading. Try it out and you'll see. </p>

[KenPapai]

<blockquote>

<p>in manual mode there is no AE lock</p>

</blockquote>

<p><br /><br /> YES there is. The exposure is what YOU set: ISO, shutter speed, and aperture. Why would you need "AE lock" in manual mode? YOU set the exposure NOT the meter's CPU.<br>

Like was suggested: <strong>spot meter in Av mode,</strong> notice the exposure. <strong>Switch your dial to M and set the exposure t</strong>o the spot meter settings. Very simple and Occam-razor like.<br /> </p>

[morthcam]

<p><em>I'll try CF4 and see how that works, but wouldn't I be changing the AE lock to AF ?</em><br>

<em><br /></em><br>

CF4 has multiple options, the first (what Bradford said) puts the exposure lock on the shutter and AF lock on the back button. <em><br /></em></p>

[g dan mitchell]

<p>People sometime misunderstand the purpose and intent of spot metering. They think it is so that you can just meter a very small area of the scene and "expose correctly" for that area. It isn't that simple, and that's not really what spot metering is designed for.</p>

<p>Spot metering is a fundamental tool for using, for example, the zone system approach. You would spot meter a very small brightest area, a very small darkest area, and one or more important intermediate areas and then calculate an optimum exposure that you would likely enter in manual mode.</p>

<p>If you spot meter a tiny area of the scene and then let the camera decide on settings, while there are a few situations where this might work, in most cases the result will not be what you want. With DSLRs it is often a better approach to simply "use the camera as a meter" and let it make an initial automatic exposure in whatever mode works best for your intended result. Then inspect the histogram and look for the "blinks" in the LCD display and adjust accordingly from the automatic setting to optimize, probably in manual mode. This is very quick and very effective.</p>

<p>Dan</p>

[tom_berkowski]

<p>I have 5D (original). Here's what I do:<br>

1) Get correct exposure (ISO, apeture, shutter speed) through handheld meter or in camera metering + "chimping" interatively to get right exposure.</p>

<p>2) Switch to "C" on my dial, which I have set to Manual mode + CF4-1 as described above several times. I set the ISO/apeture/speed. I then focus using the * button, recompose & shoot.</p>

<p>As a variation on #2 above, there are times I have CF4 off (so focus button is shutter button). I focus, turn off autofocus on lens (move from AF to MF on lens). I recompose & shoot.</p>

[www.philwinterphotography.]

<p>Sorry, guys, it just ain't that complicated. Set the mode to M (you don't have to bother setting AV first) and meter to spot. Then meter something of know tonality. A white shirt is +2, Caucasian skin is normally +1. Set your exposure accordingly. Then focus and recompose. <em>Your exposure will not change even though your meter will bounce all over the place.</em> You have "locked" your exposure by virtue of using M mode. Then take the photo and fine tune accordingly. The beauty of this method is that you won't have to touch your exposure again unless the light changes.</p>

[scott_ferris]

<p>Phil, that is what I said two days ago, I don't understand why some people make this so complicated. Get a reading, set your values, check your histogram, and shoot.</p>

[KenPapai]

<p>And the OP goes missing again... ;-)<br>

Nothing rocket science at all about using M to "lock in" your exposure.</p>