Lighting 102 - 7.2: Time in a Bottle

Before we get to the assignment for this last unit in Lighting 102, I have one more technique for you to consider when using time as a variable for your flash photos. It's very useful, because it acts as a gear multiplier for those of you who may not have as many strobes as you'd like.

Given that a flash can record it's subject in an instant -- even if the exposure is spread out over a long time -- there are several ways to stretch a flash into looking several light sources when shooting a static object.

You'll remember Jonathan Boeke's cool shot from July in which he ran around during a time exposure popping his green-gelled flash from behind several trees to create this photo. It's a great idea, and you can easily see how it can make one flash look like a whole bag full of lights.

But you'll need a very dark environment and a long shutter to have time to make all of your locations for popping the flash. And if you screw up one pop, your whole photo is shot.

Another way to approach this is to use your camera's multi-exposure setting, if it has one. Some do, some don't. If your camera is so equipped, this gives you great flexibility and time to spare when you are lining up your various light locations.

If you do not have three PW's (one to manually trigger, one on the camera in relay mode and one on the flash) you'll want to wrangle a button-pushing friend to help. The camera, obviously, should be on a tripod.

If you'll remember, we set up a tag cloud for others who wanted to try this technique. You can see their resulting photos here.


For my take on Jonathan's night woods shot, I chose the multiple exposure route because it allowed me to control the ambient light. There was still plenty of twilight when this photo was taken, but since I shot each multi-exposure pop at a 250th of a sec, I could totally control my ambient.

I could even have chosen to lay down a, say, three-stop-underexposed ambient frame to flesh out the rest of the photo if I wanted. But I liked it better on black.

I tried the straight multiple exposure method about ten times (all pretty time consuming, too) and never got one I liked. So I decided to cheat. I use that term loosely, as there are no real "rules" for this kind of shot.

As far as I am concerned, any tool you have is fair game. So I decided to do this multi-exposure on separate frames and combine them in Photoshop. I shot each frame separately, and added each new photo a layer at a time, and combined them using the lighten mode. This simply compares the two layers, pixel by pixel, and the lightest pixel in a given location wins.

Which means it pretty much works like a multi-exposure -- except you can tweak each layer / flash pop before you add it to the final photo. You can shift the color, exposure, etc. It's a fantastic trick for shooting large scenes with one speedlight. I used my single loaner SB-900 for this one. (It turned back into a pumpkin last week and had to go back to Nikon.)

Thanks much to Photoshop Honcho Ben Willmore for the heads-up on the lighten technique.


The best way I can explain the advantage of being able to build this exposure around the totally controlled ambient is to say that I shot the photo at left almost an hour after the multi-pop photo. I think that kind of control is pretty cool, when you consider you are getting it with just one speedlight.

The soft look in this photo came from the fact that I used a plastic Holga lens (more on that here) on my D3. Kind of ironic, really - a $50 Holga lens on a D3. But I love the look, when combined with hard strobe.

And that's exactly what I did here -- camera on tripod, ambient underexposed a stop or two and a 30-second exposure. Just tripped the shutter and walked up to the side of the tree (out of the frame, tho) and popped the flash manually.

My choice of shutter for the multi-exposure shot above turned day into night, and the long shutter for this one turned night into day. Understanding flash / ambient control lets you do some cool stuff.


Speaking of Doing Cool Stuff

Now, it's your turn. You have just about everything I have to give on time manipulation of your flash photography. So for this, our last L102 assignment, your job is to shoot a still life. Your photo should contain a combination of flash and some form of time-based manipulation.

That's pretty wide open, I know. I wanted it to be that way because I thought we would make this one a little more interesting.

At the close of this assignment I will choose one shot, and the winner gets a set of Lighting Seminar DVDs, shipped anywhere in the world. Hopefully that will add a little layer of fun to the last assignment.


The Details

The deadline for this assignment is midnight, local, September 20th. Please make sure your photos are in Flickr and tagged before then. If you are a newb to Flickr, go ahead and sign up now (it is fast and free) and drop some photos in so you can get through the week-or-so waiting period before they let your tagged photos show up.


Here are your tags:

Strobist
Lighting102 (Note: no spaces)
Assignment
TimeInABottle (Note: no spaces)

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.

Judging will be by a committee of one (yours truly). I will choose based on technique, creativity, how badly I wish I would have taken it myself, my general disposition at the time, what I may have had for breakfast in the morning, etc.

PLEASE NOTE: Please do not enter pre-existing photos into the running for the DVDs. I would like to award them to the best photo shot specifically for this assignment. We are doing this one on the honor system, but make sure your EXIF can back you up...

Best of luck to all, and I am looking forward to seeing what you come up with!

Posted in: