Exposure Tutorial

[JMSetzler]

Greetings to the Group :)

I have recently completed a free tutorial on 'Exposure' that I would like to share. It's a 1.1mb Adobe Acrobat document and it's available here:

http://webpages.charter.net/setzler/exposure.pdf

I am a Canon 10D owner (or I will be as soon as it arrives in the mail) :)

Cheers

John Setzler
Hickory, NC

[Jesper]

Here are some more links to interesting articles about exposure, that you can read while you're waiting for your 10D (by the way, I've also ordered one and I'm waiting too..... :-):

Understanding Exposure
http://www.luminous-landscape.com/tutorials/understanding-series/understandexposure.shtml

Expose (to the) Right
http://luminous-landscape.com/tutorials/expose-right.shtml

The Ultimate Exposure Computer
http://www.fredparker.com/ultexp1.htm

[JMSetzler]

I have seen most of those :) I wrote the one that I linked above... just wanted to share it...

[spaceman]

JMSetzler wrote:
I have seen most of those :) I wrote the one that I linked above... just wanted to share it...


Thanks for sharing. The info will be extremely helpful, as I am a new to the world of manual photography.

[Ikinaa]

JMSetzler wrote:
Greetings to the Group :)

I have recently completed a free tutorial on 'Exposure' that I would like to share. It's a 1.1mb Adobe Acrobat document and it's available here:

http://webpages.charter.net/setzler/exposure.pdf

I am a Canon 10D owner (or I will be as soon as it arrives in the mail) :)

Cheers

John Setzler
Hickory, NC


As you are the author of this document, I have one small remark.
On page 9 (concerning the F-Stops) You write "When we look at this chart for the first time, it probably won’t make much sense. The numbers here don’t seem to have any real meaning."
I think it makes sense.
2.8 ~= sqrt(2) * 2
4 ~= sqrt(2) * 2.8
etc.
[nb : sqrt = square root]
This is because the size of a disc.
If you double the surface of a disc (= pi * (r ^ 2)), the diameter is multiplied by sqrt(2).
The surface of the disc of the aperture is in this case the quantity of light that enters the lense.
Another part : One could say why does the f-number increase when the light gets less. You noticed that the aperture is written f/2.8 (f divided by 2.8 ).
So light gets less because it is divided by a bigger number.
This is how I make it up.
Anyone's got a better explanation?
Any objections by professional mathematicians or physics?

[JMSetzler]

It makes sense to us but probably not to a beginning photographer or anyone who doesn't know the math behind the madness :)

[Ikinaa]

Does anyone know a book (paper or e-) about the mathematics or physics behind photography?
I think things are easier to use when you know how they work... :D

[msvirick]

Woh, what a help.
Thank you all for your help in educating all of us.