Exposure 101

[gstark]

This is the first of a number of tutorials that we'll be creating and making available to you.

Many thanks to Cricketfan for all of his hard work in preparing this.

Please PM me with suggestions of other tutorials that you feel may be useful (or offers to prepare some).

Enjoy.

[Kristine]

Hi Gary

This tutorial was a great idea and will be very useful to us members



Cricketfan

Thanks for taking the time to make such a valuable resource - this is much appreciated.

[ru32day]

Thanks, Cricketfan for this tutorial.

I was trying to explain the relationship between shutter speed and aperture to my son last week. He looked quite confused. I'll go back with your hosepipe example, which is much clearer

[Glen]

Thanks Cricketfan, very impressive

[phillipb]

Good work, the only other thing that I would suggest is to wherever possible add some photos to illustrate the example.
This series should become compulsary reading.

[brembo]

Looks like some valuable information, and as suggested, some photos to go along with the examples would work a treat.

I'll have to give it a more thorough read over when I'm not so tired.

[W00DY]

Will read this tomorrow (hoping for a slow day at work!!!).

This is a great idea for the forum and look forward to one day maybe knowing enough about something (does it have to be photography specific?) to write one myself

W00DY

[christiand]

Thank you very much for starting the tutorials.
This will be a great source of photographic knowhow.

Cheers
CD

[birddog114]

We have few tutorials in Important link section, it might worth to re-post or re-direct to this section.

[gstark]

Will read this tomorrow (hoping for a slow day at work!!!).

This is a great idea for the forum and look forward to one day maybe knowing enough about something (does it have to be photography specific?) to write one myself :D

W00DY

Woody,

theywould need to be relevant for the members of this forum.

[gstark]

We have few tutorials in Important link section, it might worth to re-post or re-direct to this section.

Birddog,

Yes we do, but those are not original content, and they're mixed in with other links as well.

The intention is that these are going to be original content only, and only one thread per tutorial, thus hopefully making it easier for people to find what they want.

[Geoff]

Cricketfan - this is brilliant, GREAT work. I might show this to my fiancee who is always interested in learning more about the camera and how it works, I can tell her but to be able to read what you've compiled in a very simple to follow format, it's a real winner. Thanks for your worthy contribution!

Geoff.

[bwhinnen]

Great work Cricketfan, do you actually run workshops and so forth, I may possibly be interested?

One thing that I know someone, my wife for example, may find confusing is that f3.5 is larger than f22, maybe a reference to the fact that f3.5 or f# is actually another way of representing f/3.5 or f/22. Then explain that the f is the focal length and that is the reason those telephoto lenses with a bigger f-number have such a big barrel diameter. Or am I off the mark and you'll do an article specifically on aperture and so on?

Cheers
Brett

[the foto fanatic]

Hi Brett & thanks for the note.
Instead of a formal workshop, why don't we have an informal one with all the Brisbane D70 community? Everyone can ask questions of each other in an atmosphere of friendship & learning.
I believe we have contemplated a couple of dates after the festive season when we can all get together.
I'll look forward to meeting you then.  PS - I am going to do a more detailed article on Aperture & Depth of Field, as well as another on Shutter speed & motion.
Cheers
Trevor

[bwhinnen]

Hi Brett & thanks for the note.
Instead of a formal workshop, why don't we have an informal one with all the Brisbane D70 community? Everyone can ask questions of each other in an atmosphere of friendship & learning.
I believe we have contemplated a couple of dates after the festive season when we can all get together.
I'll look forward to meeting you then.  PS - I am going to do a more detailed article on Aperture & Depth of Field, as well as another on Shutter speed & motion.
Cheers
Trevor

That'd be sweet Trevor. I'll be up for an informal meet and greet.

Can't wait for your other articles.

Cheers
Brett

[dooda]

Cricket Fan,

I did as you suggested in your tutorial and sent water into my camera from a hosepipe to an interesting effect. However I wouldn't recommend this to anyone else as my camera doesn't seem to work as well anymore. The rest of the tutorial seems to be pretty good advice though.

[the foto fanatic]

hi dooda
Sorry to hear about your bad luck with the hosepipe!
Maybe you have a faulty stop-cock!

[birddog114]

Cricket Fan,

I did as you suggested in your tutorial and sent water into my camera from a hosepipe to an interesting effect. However I wouldn't recommend this to anyone else as my camera doesn't seem to work as well anymore. The rest of the tutorial seems to be pretty good advice though.

dooda,
Sorry to hear it! but how?
Anything can be fixed? hope you'll have the solution for it!

[ajax]

Gary,

great idea. Thanks for implementing it. Very handy for novices like me. Cricketfan thanks for the article and the efforts you have put in.

cheers,
ajax

[ru32day]

It worked! Used the tutorial to explain this stuff to my son, then explained the confusing stuff about F stops being 1/whatever. Even asked him some relevant questions - how would you get a shot that had was clear front to back of the shot - how to pick out a person and blur the rest etc (just big or little, not exact settings) and he got it all correct.

One further thing that I use as a memory check - Bigger DOF requires a bigger number on the guide, smaller DOF a smaller one. I know it's actually a smaller aperture and a bigger one respectively, and the numbers are really fractions and therefore the numbers aren't really bigger, but smaller (trip over tongue again) but I find this an easy memory check (yes, I always liked My very easy memory guide seems useful naming planets as well).

[shakey]

Gotto get a few posts up so I can post some photos!
AutoISO, as an additional tool in getting correct exposure, seems to be neglected by most, dismissed by others and then damned by faint praise by the rest. I think it is a valuable tool when you want to have absolute control of the speed and the aperture you want to shoot at. I'm thinking outdoors action shots. It is a tool unavailable to film photographers.

shakey

[gstark]

Gotto get a few posts up so I can post some photos!
AutoISO, as an additional tool in getting correct exposure, seems to be neglected by most, dismissed by others and then damned by faint praise by the rest. I think it is a valuable tool when you want to have absolute control of the speed and the aperture you want to shoot at. I'm thinking outdoors action shots. It is a tool unavailable to film photographers.

shakey

Shakey,

Welcome. You can post images at any time; there's no restriction on post counts for that.

There was a recent discussion on auto-iso - maybe 4 weeks or so back? might be worth looking for that too.

I personally think it's almost worthless; you have no idea of when it's going to change, nor what it's going to change to. If I need a fast ISO, I should be able to recognise the situation and adjust my shooting technique as appropriate.

[the foto fanatic]

Hi shakey & welcome

Yes, be wary of auto-ISO. If you want to use it, my tip would be to use it in Manual mode only. That is the only way you retain full control of aperture and shutter speed. Even in this case, you are giving the camera carte-blanche to introduce noise to your shot at whatever level it wants. Not desirable, IMHO.

If you use auto-ISO in Aperture-preferred, the camera actually changes shutter-speed before it changes ISO.

So, at best I believe it to be a tricky setting, and wouldn't recommend its use in normal circumstances.

[shakey]

Shakey,

>Welcome. You can post images at any time; there's no restriction on >post counts for that.

..Thanks for that. I was really thinking of the "challenges" which require a 5 post threshold

>There was a recent discussion on auto-iso - maybe 4 weeks or so back? >might be worth looking for that too.

>I personally think it's almost worthless; you have no idea of when it's >going to change, nor what it's going to change to. If I need a fast ISO, I >should be able to recognise the situation and adjust my shooting >technique as appropriate.

...For the most point I agree with you, but I disagree that it's "almost worthless". I think its useful in fading light (or rapidly changing light) when you are trying to freeze action ( eg a rodeo as dusk falls, or as clouds pass across the sun). I only use it in S or M mode, and only in certain situations. It only kicks into action when correct exposure is not achieved at the default ISO. I believe (but can stand corrected) that auto ISO will only bump the ISO up to the number which gives correct exposure. If it's a choice between an underexposed shot or a "noisy" well exposed shot I'll usually take the well exposed shot anytime, and use Noise Ninja to reduce the noise if necessary.

So taking it point by point
1. You DO know when it is going to change. It will change when your selected shutter speed, aperture and default ISO will result in an underexposed shot.
2. You DO know what the ISO will change to...it will change to lowest ISO which will lead to a correctly exposed shot

I see auto ISO as a "last chance" option to get correct expose in photographically inclement situations. Used appropriately I think it's a useful tool.

Anyway I'll get off the soapbox now and congratulate you on a wonderful site and resource for dSLR users.


shakey

[gstark]

1. You DO know when it is going to change. It will change when your selected shutter speed, aperture and default ISO will result in an underexposed shot.

As the person behind the camera, I'd expect that one's eys should be able to recognise the changing light conditions, and one should be able to adjust exposure parameters as required.

2. You DO know what the ISO will change to...it will change to lowest ISO which will lead to a correctly exposed shot

So, that's, er, um, 400? 600?? 1320? 800??

The reality is that you don't actually have a clue.

I see auto ISO as a "last chance" option to get correct expose in photographically inclement situations. Used appropriately I think it's a useful tool.

I agree that it's a "last chance" tool. I suspect my interpretation of "last chance" may differ slightly from your's.

[Big Monkey]

Thanks for writing such a informative article. Having read "Photography in a Nutshell" and this one, I am starting to think I may be learning something! Really useful for beginners and definitly gives me more confidence in understanding DSLR's.

Great Work, keep it up.

Cheers
Ryan

[tanmoy1048]

Very useful links...

http://digital-camera-tutorial.blogspot ... l/Exposure

[Victor03]

Gary,

I notice that the URLs for the older tutorials no longer work.
Have they been replaced by other material? I could not see any replacements in the DSLRUSER website.

Perhaps they could be refreshed?

Cheers.