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becca
24-01-2009, 2:21pm
I am currently doing an assignment on the f/16 RULE. So far, the info i have is:

The rule states that if working in full sun, set the aperture to f/ 16 and the shutter speed will be equal to the reciprocal of the ISO. In practice, for example you are shooting at an ISO of 100 in full sun; simply set the aperture to f/ 16 and the shutter speed to the reciprocal of the ISO, which is 1/100 second.

You can of course use any combination of shutter speed and aperture as long as it converts back to f/ 16 at 1/100, such as f/8 at 1/400 or the like. This trick generally works quite well, but be mindful that if the scene is a bit shadowed then you must do a bit of interpretation and make some exposure adjustments

I sort of understand it but the maths gets me a bit muddled up! Does anyone have an easier way of explaining it? Would that mean that f/4, would be ISO 1600, taken at 1/1600 ?!!

clcollins
24-01-2009, 3:43pm
No idea about this myself
However I had a lot of difficulty reading your post as you coloured your writing yellow and I have the white skin/background set for this site, meaning your text comes up as yellow on a white background, makes for hard viewing. Just so you know in future posts
Cheers
Cath.

becca
24-01-2009, 3:45pm
Thanks - I'll change it.

The f/16 RULE
I am currently doing an assignment on the f/16 RULE. So far, the info i have is:

The rule states that if working in full sun, set the aperture to f/ 16 and the shutter speed will be equal to the reciprocal of the ISO. In practice, for example you are shooting at an ISO of 100 in full sun; simply set the aperture to f/ 16 and the shutter speed to the reciprocal of the ISO, which is 1/100 second.
You can of course use any combination of shutter speed and aperture as long as it converts back to f/ 16 at 1/100, such as f/8 at 1/400 or the like. This trick generally works quite well, but be mindful that if the scene is a bit shadowed then you must do a bit of interpretation and make some exposure adjustments.

I sort of understand it but the maths gets me a bit muddled up! Does anyone have an easier way of explaining it? Would that mean that f/4, would be ISO 1600, taken at 1/1600 ?!!

ricktas
24-01-2009, 3:53pm
Thanks - I'll change it.

i changed it for you Becca. Members can only edit posts for 60 minutes after the original post time

The Sunny 16 Rule, which like many photographic rules, is more a guide than a definitive Rule!

Basically you have sunny 16 right. On a sunny day set your aperture to f16, then select your ISO, then set your shutter speed to 1/ISO. So if you set your ISO to 800, your shutter speed using the Sunny 16 Rule would be 1/ISO or 1/800th of a second.

Aperture ::: Lighting Conditions ::: Shadow Detail
f/16 ::: Sunny ::: Distinct
f/11 ::: Slight Overcast ::: Soft around edges
f/8 ::: Overcast ::: Barely visible
f/5.6 ::: Heavy Overcast ::: No shadows

The above table expands on the Sunny 16 Rule for other light conditions (ie Not Sunny).

Here is a link to more information on this : http://guidetofilmphotography.com/sunny-16-exposure.html

bigbikes
24-01-2009, 4:11pm
Great tip Rick.
I will have to give that a try.
I hadnt heard of it before.
Cheers
Peter
:th3:

learning
24-01-2009, 4:26pm
Thanks - makes sense, I have got something to work with.

reaction
24-01-2009, 6:18pm
interesting. but wouldn't you just check your exposure as you do the shot and adjust?

ricktas
25-01-2009, 8:07am
interesting. but wouldn't you just check your exposure as you do the shot and adjust?

Yep, but remember we are dealing with newbies, and its all part of the learning curve. This 'Rule" has been around from way before we had metering in cameras.

becca
25-01-2009, 4:17pm
Thanks Rick. That's really helpful.

Kym
26-01-2009, 1:54pm
Sunny 16 Rule
The basic exposure rule for an average scene taken on a bright, sunny day is to use f/16 at a shutter speed equivalent to one over the ISO setting; that is, f/16 at 1/100 sec (or the nearest equivalent, 1/125) at ISO 100, etc. In other words, the shutter speed will vary according to the ISO you are using. From this you can interpolate other exposures.

Here is the Sunny 16 rule laid out in tables for common settings.

dbax
26-01-2009, 2:38pm
thats a handy little table Kym.
Cheers:th3:

Ian
26-01-2009, 3:24pm
thanks for bringing this up Becc, and thanks to those who replied because it handy to recap on things to jog ones memory. so thanks again to those folk. :food04: :) ian

TOM
26-01-2009, 6:41pm
interesting. but wouldn't you just check your exposure as you do the shot and adjust?

Remember that not everyone has a light meter in their camera and sometimes they don't have a hand held light meter. The sunny 16 rule is suprisingly accurate, good enough for transparencies. When shooting print film, then there is plenty of latitude to be even a couple of stops out on your calculation. It is also quite a buzz to shoot without a meter, without autofocus, manually setting all parameter with no electronics, and nail the shot.

Some lenses, like those found on a Carl Zeiss Hasselblad lens, will allow you to set the shutter speed and aperture then lock the two together. This allows you to set any aperture or shutter speed desired, whilst keeping the original combination juxtoposed. This makes the 'maths' easier.