Metering off Greens

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Anand
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Hello all,

I've recently been reading Understanding Exposure, hence have been sparked with this basic question..

(There has been a technique described in the book (Mr. Green Jeans) for metering off green (grass, plants, etc) the correct exposure is to set it to -2/3)

My question is how do I do this? I shoot on Nikon D5000 and getting used to the Manual mode. Do understand the working and concept of using on-board light meter, however, how much of the pointer do I need to move in order to get -2/3? A more precise question would be how much does each point indicate, there are seven point on each side (-/+)?

Thanks,
Anand
 
There should be big points and little points in between the big points. The little points are 1/3 the big points are 1 full stop. So to get -2/3rds, go two little points backwards.
 
I'm a canon man so the control names might be slightly different but you need to set your metering mode to (ideally) spot metering or if your camera doesn't do spot metering then set it to partial metering. Then aim your camera at the greens in question and assuming you're using Manual mode change either the aperture/shutter speed/iso so the the little mark on your light meter display is set at or around -2/3 of a stop.

Your cameras manual should explain to your what the light meter display on your camera means but generally they're a series of vertical lines that something like this with a little arrow above it

-2 -1 v 0 +1 +2
IllllIllllIllllIllllI

and -2/3 of a stop is about where the red mark in the above diagram would be.

If you hadn't already guessed the -2 -1 0 +1 +2 etc refer to stops so -2 on the light meter display means your currently metering that part of the scene at minus 2 stops below average.

Hope that helps :thumbs:
 
Hello all,

I've recently been reading Understanding Exposure, hence have been sparked with this basic question..

(There has been a technique described in the book (Mr. Green Jeans) for metering off green (grass, plants, etc) the correct exposure is to set it to -2/3)

My question is how do I do this? I shoot on Nikon D5000 and getting used to the Manual mode. Do understand the working and concept of using on-board light meter, however, how much of the pointer do I need to move in order to get -2/3? A more precise question would be how much does each point indicate, there are seven point on each side (-/+)?

Thanks,
Anand

Mr Green Jeans (I'm not a big fan of Peterson's Understanding Exposure book :() is a method of using a reference tone in difficult metering circumstances.

For example, a bride and groom on the grass. If you meter off either of them you'll get a skewed result, but you know what exposure value green grass is, so meter off that, make the -2/3rds adjustment, and you're there. Grass varies a lot though and it's usually lighter than that, requiring no exposure adjustment.

You can do the same off any known tone. Grass, tarmac, brickwork etc, so long as you're confident of the brightness value. A popular one is to use the palm of your hand and add +1.3 or something close to that.
 
Thank you all for your answers. will do some field work tomorrow as got a day off :)..will post here again if I am stuck..determined to go full manual on my camera...
 
Shutterwork, was asking about exposure not white balance.

Edit: Beat me to it Tom.
 
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I use grass to expose at sports... having a set exposure adjustment is plain stupid.. apart from the different shades of grass and different lighting condition sometimes to the extreme..

If using anything like grass, pavement, wall or anything else then it should be a starting point and then a slight adjust accoridngly... IMHO
 
I use grass to expose at sports... having a set exposure adjustment is plain stupid.. apart from the different shades of grass and different lighting condition sometimes to the extreme..

If using anything like grass, pavement, wall or anything else then it should be a starting point and then a slight adjust accoridngly... IMHO

Yes, though to be fair to Byan Peterson this time (much as it galls me :D) the examples in the book are rather more lush darker green foliage subjects, for which -2/3rds would be about right.

To the OP, using reference tones like this is a very handy technique to maintain correct exposure when shooting in manual, especially in changing conditions.

If you were at a motor race for example, the cars will be white, black, red etc, backgrounds will change from sky to grass to shade, and clouds will come and go. Complete nightmare.

So, take a spot reading off a constant reference tone, something that is in the same light as the subject - tarmac, grass, whatever - that you can access easily and reference at any time. Check and adjust the exposure so that it's just how you want it, then go back to that reference tone and note the shift from the spot metered value in the viewfinder. Let's say it is +2/3rds of a stop (+0.6) for sake of argument, though with most tarmac/grass it will close to zero - a nice mid-tone.

Now it doesn't matter what the the subject is, or if the light changes from bright sun to thunderstorm, just point the camera at your reference tone, adjust the exposure to +0.6, and you can't be wrong.*

*PS Except if it rains on your patch of tarmac, that will make it darker and mess things up :D
 
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Check and adjust the exposure so that it's just how you want it, then go back to that reference tone and note the shift from the spot metered value in the viewfinder.

Sorry to be a pain but does this mean that you would take a shot and then adjust the exposure until you liked what you seen on the display?

e.g. take a shot of the grass which is in the same light as your subject and check if it's over or under exposed. Adjust the exposure until the grass looks 'right' to you, then note what the reading is on the light meter in the viewfinder?
 
Sorry to be a pain but does this mean that you would take a shot and then adjust the exposure until you liked what you seen on the display?

e.g. take a shot of the grass which is in the same light as your subject and check if it's over or under exposed. Adjust the exposure until the grass looks 'right' to you, then note what the reading is on the light meter in the viewfinder?

In Manual...Point at the grass.. no need to take a picture... note the settings for a correct exposure ..then set your camera to those settings.. shoot your subject (ignoring what the exposure indicator shows) and it should be pretty close to the right exposure.. if not then adjust up or down...re shoot and check until happy .

In simplistic terms :)
 
Sorry to be a pain but does this mean that you would take a shot and then adjust the exposure until you liked what you seen on the display?

e.g. take a shot of the grass which is in the same light as your subject and check if it's over or under exposed. Adjust the exposure until the grass looks 'right' to you, then note what the reading is on the light meter in the viewfinder?

Yes, exactly that.

In Manual...Point at the grass.. no need to take a picture... note the settings for a correct exposure ..then set your camera to those settings.. shoot your subject (ignoring what the exposure indicator shows) and it should be pretty close to the right exposure.. if not then adjust up or down...re shoot and check until happy .

In simplistic terms :)

That's not quite what I meant. That is more using grass as a good approximation to mid-grey for exposure measurement purposes, when the subject itself is difficult to read accurately. And that works fine :)

What I was on about is a constant reference tone reading, to check that exposure is always maintained. For that, you can use any convenient subject, and gass is a good one because there's usually plenty of it around.

Or the palm of your hand is also good, so long as you are standing in the same light as the subject. Whatever the reference tone, just note the adjustment shift that was needed for correct exposure, and it will always be right.

In fact the palm of your hand (not the back) is double-good because you already know (from previous checks) exactly what it is - very likely about 1-1.5 stops lighter than mid-grey. Mine is 1.3 stops. So, if you are standing in the same light as the subject, take a spot reading of your palm, in manual, and set the needle to +1.3. Exposure will always be correct - it's basically taking an incident light reading.
 
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That's not quite what I meant. That is more using grass as a good approximation to mid-grey for exposure measurement purposes, when the subject itself is difficult to read accurately. And that works fine :)

eeerm yeagh

What I was on about is a constant reference tone reading, to check that exposure is always maintained. For that, you can use any convenient subject, and gass is a good one because there's usually plenty of it around.
.

I ahve read it a couple of times and I still dont see the difference... the only way the exposure will change is if the light changes.. so i recheck the grass.. how is it different?

seriously i cant see what the difference is between the two...

ADDYONBITafter reading again... :) is your example to go back into a semi auto mode like AV so once you took your first reading and compensated then no matter how much the light changes then it will always be the correct exposure?
 
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eeerm yeagh



I ahve read it a couple of times and I still dont see the difference... the only way the exposure will change is if the light changes.. so i recheck the grass.. how is it different?

seriously i cant see what the difference is between the two...

ADDYONBITafter reading again... :) is your example to go back into a semi auto mode like AV so once you took your first reading and compensated then no matter how much the light changes then it will always be the correct exposure?

Not quite. The difference is you are using grass as both a mid-tone for exposure purposes (as you would a grey card) and also as a reference tone.

You said that you don't need to take a picture, which you don't if the grass is conveniently mid-grey, but if your reference is a different subject, like darker tarmac, or maybe a light painted wall, then you do need to take a shot, probably a couple (check the LCD/histogram/blinkies) to make sure the exposure is actually correct. Then note the shift when you aim the spot over your reference target, and that is your adjustment amount.

From the top then (and I know you know this - for the benefit of others ;)) this is how it might work. At a motor race, cloudy windy day, cars all colours of the rainbow and you're shooting and panning all over the place. Exposure nightmare, and because you've got a long lens fitted, taking a reading from the palm of your hand is quite difficult.

So you set up in manual, and by trial and error get the exposure just as you want it. Now right in front of you is a nice clean patch of tarmac, which you can see from wherever you're likely to be shooting from. Take a spot reading off it, and note that the needle indicates -0.3 (or whatever it is, it doesn't matter). You now know that whatever happens to the light, if you just take a reading from that bit of tarmac and adjust the exposure to -0.3, you'll be right on.

You often see pros at events like this pointing their long lenses at the ground for no apparent reason - they're just checking their reference tone.
 
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You often see pros at events like this pointing their long lenses at the ground for no apparent reason - they're just checking their reference tone.

Just like I do when I point at the grass in the middle of the pitch to check the exposure part way through a match.. :)
 
Thank you all for your inputs..especially Richard for a detailed explanation...do like your knack of explaining things as always :)..Sure this thread has opened more discussion about the actual metering technique when all I really wanted to know is the value of each pointer on Camera's built in light meter..based on answers here (especially Tom's) and my manual I guess each point has a value of 0.33 on my Nikon D5000, so if I need to set 2/3, I'll need to move 2 points on the scale - hope I have got this right?

Now coming back to metering technique since this is being discussed here - I tried using Sky Brothers (as Mr. Peterson swears by this) during my recent visit to Southport Airshow. Tried metering off the blue sky (half-way between the son and the farthest horizon), unfortunately was really disappointed with the results. The underside of the planes (e.g. Vulcan) really looked underexposed losing details) whereas these came alright when I shot on Shutter-Priority mode. So what went wrong? Is it better to shoot air-planes on S modes. Alternatively, what should I meter off when shooting airshows in M mode?
 
Just like I do when I point at the grass in the middle of the pitch to check the exposure part way through a match.. :)

:thumbs:

Thank you all for your inputs..especially Richard for a detailed explanation...do like your knack of explaining things as always :)..Sure this thread has opened more discussion about the actual metering technique when all I really wanted to know is the value of each pointer on Camera's built in light meter..based on answers here (especially Tom's) and my manual I guess each point has a value of 0.33 on my Nikon D5000, so if I need to set 2/3, I'll need to move 2 points on the scale - hope I have got this right?

Now coming back to metering technique since this is being discussed here - I tried using Sky Brothers (as Mr. Peterson swears by this) during my recent visit to Southport Airshow. Tried metering off the blue sky (half-way between the son and the farthest horizon), unfortunately was really disappointed with the results. The underside of the planes (e.g. Vulcan) really looked underexposed losing details) whereas these came alright when I shot on Shutter-Priority mode. So what went wrong? Is it better to shoot air-planes on S modes. Alternatively, what should I meter off when shooting airshows in M mode?

Your're welcome Anand. Sorry for opening another can of worms here, which is a bit off your topic, intending to be helpful ;)

Yes, your camera's meter default with be in 1/3rd (0.33) stops increments, though you can probably go into the custom functions and reset that to 0.5 stops if you prefer.

As I said, I'm no fan of Mr Peterson and his book inexplicably popular book Understanding Exposure. Just forget the damn Sky Brothers! Though they have nothing to do with shutter-priority or other shooting modes - they're supposed to refer to key metering tones... Like Mr Friggin Green Jeans :cuckoo:

When shooting planes, you often have a problem, especially in bright sun. The underside of the aircraft will be much darker than the top, and there's nothing you can do about that except choose the best compromise. If it's a bit cloudy or overcast, you'll get better results on that score.
 
Thanks Richard...Please no need for apologies...it's all part of learning and will do me good..honestly.

Will try forgetting Sky Brothers...TBH it was a bit confusing as I didnt feel that chapter was well written IMO.

So Richard, would you ever shoot planes in Manual mode then? If so what do you take meter reading off in obvious absence of tarmac? Grey cards or palm technique? Thanks.
 
Thanks Richard...Please no need for apologies...it's all part of learning and will do me good..honestly.

Will try forgetting Sky Brothers...TBH it was a bit confusing as I didnt feel that chapter was well written IMO.

So Richard, would you ever shoot planes in Manual mode then? If so what do you take meter reading off in obvious absence of tarmac? Grey cards or palm technique? Thanks.

Yes, I would definitely shoot planes in manual - prefered mode, because the brightness of the sky is going to vary a lot as you pan around, towards the sun etc, whereas the light on the plane will be the same. Think of manual as a Set & Lock mode - it won't change unless you change it, regardless of the light.

As for establishing correct exposure, that's difficult with planes as the top is in bright light, possibly direct sunshine, and the underside is in shade, and always surrounded by bright sky.

So I would establish exposure by trial and error, as I often do with tricky subjects, by taking a test shot and checking the LCD, the histogram, and always with blinkies (highlight alert) enabled. Then when I've decided what I want, set and lock it in manual.

You still have tarmac! And grass, and the palm of your hand! The point is, you would use these as a reference tone, to check if the light changes. If a cloud comes over, then the reference tone gets darker, just as the plane gets darker - the relationship between the two in exposure terms remains constant.

So, as described above, when you have decided on your exposure you take a spot reading from the runway as your reference tone and note that when you do the meter indicates -0.3 (for example). You now know that whatever happens to the light, if you take a spot reading of the runway and adjust the exposure so that the meter reads -0.3, then exposure is correct. If a cloud comes over for example, your overall exposure could drop by maybe a couple of stops, but if you always maintain that -0.3 differential, you'll be okay.
 
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Thanks for your very detailed answer Richard. Does make sense. TBH from the time I've started shooting in Manual mode have started really enjoying photography. So just need to keep it up.

Thanks once again.
 
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