Tuesday, October 02, 2007

Lighting 102: Assignment - Balance

We have spent the last three weeks studying light balancing and producing photos in fairly restrictive exercises. We have a lot of people doing the work it takes begin to understand the complete and subtle controls you have over the dance that happens in your photos between strobe and ambient.

You have shot into sunsets, flashed against harsh sun and built up your backgrounds with ambient indoor light. These were three very specific techniques, but they all point to a better understanding of ambient/flash control and balance.

Later, we'll be playing with more than one strobe at a time. But for now, this balance stuff should start to be getting intuitive if you are using one strobe.

I want to detail the techniques for balancing flash and ambient as they relate to actual camera operation, and this send you off on an assignment with a little twist -- and a nice, long deadline.

(More after the jump.)
_______________________


Controlling Your Light from the Camera

Assuming just one flash and ambient light, there are only three combinations with which to control the two variables.


1. To alter flash and ambient levels together:

Remember, flash cares about the aperture and ambient cares about both the aperture and the shutter speed. So to lighten or darken both at once, we adjust the aperture.

If, for instance, our whole scene (flash and ambient) is too dark at f/8, we could move to f/5.6. This would lighten everything by a stop -- flash and ambient alike. Conversely, we could darken the entire scene by going from f/8 to f/11.

2. To alter the ambient level but not the flash:

As we said, flash cares about aperture and ambient cares about both aperture and shutter. So to control the ambient only, we will adjust the shutter but leave the aperture as is. Assuming you are within your sync speed, this will alter only the ambient-lit portions of your photo, as in our coffee table camera shots.

3. To alter the flash-lit area but not the ambient:

This is the most complicated of the three, but only as much as "chocolate/vanilla twist" ice cream is more complicated than either of its components.

Flash cares about aperture, and ambient cares about both aperture and shutter speed. So to alter flash only, we are going to adjust the aperture (which alters both) and compensate for the ambient by adjusting the shutter the other way.

(Sound of 2,000 heads exploding.)

This is not hard at all. Say our ambient is fine, but our flash is not bright enough. Aperture is at f/8 and shutter is at 1/60th, for the sake of argument.

So we open the flash up to f/5.6, which brightens the flash-lit area -- and the ambient, too -- by one stop. Then we close down the shutter to 1/125th, which brings the ambient exposure back to its original exposure value. (1/125 @ f/5.6 = 1/60 @ f/8, right?)

Piece of cake.

To darken only the flash but preserve the ambient exposure component, we would close down the aperture and open the shutter speed by the equal amount.
_________________________

Three slick moves which add up to total control of your lighting world. All in manual. All from the camera.



And Now for the Twist

Everyone will be doing this assignment in the nude.

No, no -- kidding. But I had you for a minute, huh?

No, the twist in this assignment is akin to the difference between algebra and physics. Stay with me on this one.

Algebra is pure math -- or pure torture if you were not a "math person" when you got to algebra. Math as an end to itself. ThisCrapWon'tEvenHelpMeBalanceMyCheckbook math. Math for math's sake.

Whereas physics is math with a purpose. Physics is math getting something done. We are talking "1/2 AT squared tells me where the water balloon will land" math. And that's cool. And your third assignment will hopefully get something done, too.


Assignment #3: Balance

Two of my friends, Rissa Miller and Nathaniel Corn, are both photographers who also happen to be married to each other. A few weeks ago, Rissa sent me an email about a project that she and Nathaniel had been working on along with two other people who I have not yet met. It's called the Thank You Calendar. It is a calendar designed for (and to raise money for) members of the armed services who are recovering from wounds sustained in a very politicized war.

Politics and opinion are the last things on Rissa's and Nate's mind. In fact, they make it a point for the Thank You Calendar to be politically neutral. Which makes this project all the more special, IMO. They are not doing the calendar for the war, or against the war. They are doing it for the people who are caught up in the war. They are neutral, yet they are trying to do some good. (Boy, that's a 180 from most people with a "for" or "against" stake in this thing...)

One hundred percent of the money raised by the Thank You Calendar will go to wounded service members recovering at Walter Reed Medical Center and to their families. The money will go to help fund visits, and buy personal items that they may need as they recover, etc.

What a neat idea. Isn't it amazing what a few people with the ability to make cool pictures can dream up? And here's the thing: There are easily 10,000 people reading this post who are working at this level, photographically. The trick is to look beyond taking pictures of, say, a camera on a coffee table and figure out how you can make the world a little better place with your camera.

So, here's your assignment with the twist:

Photograph someone in mixed flash and ambient light, using what you have learned in the Balance section to control your variables in the manner that you choose. But more important, produce a photo that makes a difference to someone. How it makes a difference, and for whom, is completely up to you.

Try to look beyond the technique to make a photo that is special in some way. Do not get so hung up on the technique that you fail to make a real picture.

Maybe there is a local organization (like a charitable foundation) whose director could use a nice portrait for an annual report.

Perhaps there is a family you know -- a single parent facing tough economic times -- who would love to have a high-quality family portrait for the holidays.

Maybe there is a centenarian in your town that deserves to have their achievement marked with a photograph.

The specifics do not matter. The magnitude of the result is not what is important. The idea matters. And the idea is, what a waste it is to be learning to do such great work only to have it sit on a Flickr page as an end-all.

If you don't want to do this, it is completely your choice. But in the same way it would be a waste of your ability to do a fine photo of a mannequin as an exercise, it would be a wasted opportunity for me not to at least attempt to harness the wonderful pool of talent and goodwill we have built together in this community in such a way as to do some good.

You want time? You got time. The single photo is not due until November 3rd. That's plenty of time to put some thought into it and pull off something neat. We'll take a little breather on the L102 new material to give you time to concentrate on applying what we have learned to an assignment with a little more depth and potential than he first two had.


Here are your tags:

Strobist
Lighting102
Assignment
Balance

and for your best shot, include the tag:

Final

You can see all of the take here. You can see the final edits here. Discussion is here -- and please use this as a clearing house for ideas. You are spread all over the world -- people from 176 countries logged on in September. Duplication of good ideas is fine, even encouraged.

It's a really good feeling to make a good picture. It is a much better feeling to make a good picture that makes a good difference. Thanks for your consideration.

And if you have time, please take a moment to check out the Thank You Calendar as an example of what a few photos can potentially accomplish.


NEXT: Balance Assignment: Discussion


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23 Comments:

Anonymous Mark Sirota said...

It's not a single image, but my "Happy Birthday" Project from two weekends ago seems to meet all the other requirements.

October 02, 2007 11:27 AM  
Anonymous Ron said...

This is perfect timing. I will be traveling to New Orleans with a group to help with home rebuilding. I planned to bring my camera, flash and PWs and take some photos of the rebuilding efforts as well as capture some of the residents' images too. I was looking forward to doing lots of balancing of flash & ambient light in order to add some nice punch to the images.

I'll be running a daily photo/story blog while we are gone so our families at home can follow along. I'll post some images at the strobist pool during the trip, too.

I'm psyched!

October 02, 2007 1:17 PM  
Blogger Q. Guillory said...

well, the Thank you calendar is a wonderful idea. And i really hope the creators can read this so i can say thank you! to them. Seems like alot of time people focus so much on the war and Bush. They forget about all the wonderful young men and woman who serve this country faithfully regardless of there feeling about the war.
AGAIN! THANK YOU SO MUCH!

QGuillory
HM2(FMF) Q. Guillory
US NAVY Hospital Corpsman ( Medic )
100 % Disabled Vet.
Hurt in Iraq with back injury currently doing much better except for paralyzed right foot.
Thank you for letting me share.
This strobist forum is great, since i can't work it gives me something to do and look forward to and keep my mind off my condition and friends and family enjoy seeing what i have learned. Thank you Strobist.

October 02, 2007 1:49 PM  
Blogger ExNihilo said...

As a math and physics student in college - I laughed seeing your references to math and physics. Awesome. Although I'd have to get with the other math majors and trash your camera for suggesting that math unto itself isn't enough. ;)

October 02, 2007 2:01 PM  
Anonymous ogalthorpe 2.0 said...

i was talking to a jr. strobist a couple weeks ago. I said "change the aperture to f/8". He said "that's 3 stops". I said "I don't care how many stops it is, just change it to f/8".

I just can't do the math. And I have a mathy-sciencey education and "career" (job). Simple math escapes me.

October 02, 2007 4:45 PM  
Anonymous Anonymous said...

Thanks for this in-depth lighting lesson. It answers my posted question to your last lesson re. the fireman and how to fix the lighting on the fireman after getting the settings correct for the ambient/background lighting. I need to re-read these several times now to sear the concepts into my brain. You do a great job explaining the nuances.

October 02, 2007 5:57 PM  
Anonymous Anonymous said...

I've been doing all my assignments in the nude!

October 02, 2007 6:27 PM  
Anonymous torarnv said...

For people struggling with the relation between shutter speeds and f-number and how many "stops" up and down you move check out the Wikipedia articles on the subject:

F-number

Shutter speed

The full stop scale is:

(more light)
* 0.5
* 0.7
* 1.0
* 1.4
* 2
* 2.8
* 4
* 5.6
* 8
* 11
* 16
* 22
* 32
* 45
* 64
* 90
* 128
(less light)

And for shutters it's:

(more light)
* 1 s
* 1/2 s
* 1/4 s
* 1/8 s
* 1/15 s
* 1/30 s
* 1/60 s
* 1/125 s
* 1/250 s
* 1/500 s
* 1/1000 s
(less light)

So if you move from f/8 to f/11 you get one stop less light. To compensate you move from 1/125s to 1/60s, which is one stop more light.

Someone correct me if I'm wrong please :)

Tor Arne

October 02, 2007 6:59 PM  
Blogger Jan Klier said...

Nice assignment. One thing wasn't clear: will any of the best finals of this assignment be used in this Thank You calendar, or was that just illustrate the point? And if not, should we be using some of the best to create a similiar calendar for a charitable cause?

That would give this community a whole new meaning :-)

October 02, 2007 9:20 PM  
Blogger David said...

Jan-

Nope. This is an individual thing. Just wanted to get people thinking a little bit beyond pictures for pictures' sake.

-DH

October 02, 2007 9:38 PM  
Anonymous Geoff Ball said...

Well done, David! It's nice to see a person in your position (a very frequented blog) suggesting such a community-oriented endeavour. There will be a lot of happy people over the next month, with many thanks to you.

October 03, 2007 1:31 AM  
Blogger Michael Shattuck said...

Great idea for this project. I think it's a great challenge for us all to consider how our passion (and if we're reading all of this it surely is a passion) can be used to impact the people around us. I think for me sometimes I'm a bit afraid that I'm just not good enough yet. But I'm not sure what I'm waiting for to feel "good enough"...maybe to be proclaimed the next Ansel Adams or something? Haha!!

Thanks for the post David.

October 03, 2007 7:39 AM  
Anonymous Anonymous said...

Dude, if in the scenario that your fill/ambient was ok, but your strobe looked weak, instead of opening up your aperture and changing your shutter speed accordingly faster, could you not just increase the power coming out of your strobe unit and stop down?
Don't you run the risk by using that technique, especially outside, that you will have maxed out your sync speed? Just curious. Thanks, SRE071003

October 03, 2007 7:53 AM  
Blogger Michael said...

Funny Universe. I quietly read this post at work yesterday. Went home last night and before bed whilst I contemplated that universe on the "Throne of Ultimate Thought". ;) I was leafing through the August 2007 issue of Rangefinder and stumbled on an article that I thought was topical on both subject and, if you can read between the lines, the assignment.

"Real Reciprocity" a different way to say Balance -- from the article "What is reciprocity? It is a relationship describing what happens when one action is coordinated in some way to another action."

http://www.rangefindermag.com/magazine/Aug07/112.pdf

October 03, 2007 8:30 AM  
Anonymous Anonymous said...

This is a cool Assignment! I know that it would be difficult at best, but what if we could come up with some kind of deal like this that could actually impact a group of people, a government, a nation!
a calendar, website, book.....with all the brains, and skill sets of the strobist group together for one cause. now that would be amazing!

October 05, 2007 2:20 PM  
Anonymous Anonymous said...

this maybe kinda newbie question, for situation 3, where the ambience is ok, flash is too weak/strong, can we dial the flash power up instead? will there be any difference with the method as suggested?

October 06, 2007 6:43 AM  
Anonymous Anonymous said...

Thank you Calendar, to benefit Veterans, what foundation are they giving the charities to?

October 31, 2007 12:05 PM  
Anonymous Martin Stephens said...

The URL has changed since the Assignment was posted. It is now at "www.thankyoucalendar.com/"

Cheers,

Martin

September 20, 2008 8:24 PM  
Blogger Dennis Pike said...

proof positive that 1 person can indeed make a difference, I find it very admirable to take the voice that you have to influence others to do some good, think how many people this has had a positive influence on. cheers

September 23, 2008 3:01 PM  
Blogger Rob said...

David,
In single strobe shots, seeing you can change the the brightness of the flash, ambient and both, would you ever need to change the strength of the flash? ie go from 1/4 power to 1/2 power?

Rob

May 11, 2009 1:50 PM  
Blogger Karen Engel Photography said...

This bit - "To darken only the flash but preserve the ambient exposure component, we would close down the aperture and open the shutter speed by the equal amount."

I just don't like the idea of "opening" shutter speed. An aperture can be open and closed, and I think it confuses the point. A shutter speed setting can only be faster or slower - not opened or closed. That's the part that made my head explode. LOL

October 26, 2009 11:10 PM  
Blogger Wil said...

David, you might want to update the links in this old post. The "Thank you" calendar URL isn't valid anymore. Just a heads-up.

February 22, 2014 3:32 PM  
Blogger David Hobby said...

@Wil- Indeed, L102 is in the process of a complete retrofit. With a lot more than fixed links. :) Coming soon.

February 24, 2014 1:39 PM  

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