Tuesday, June 28, 2011

Flash Sync At 1/320 With The Nikon D7000

 
Most modern SLR Camera bodies have a flash sync speed limit of one 200th or 1/250th of a second. Of course, using high-speed sync, which is available on both Canon and Nikon bodies, you can synchronize at whatever shutter speed you like... sort of. The price you pay for the privilege of higher sync speed is a substantial loss in flash power. That is because it does the continuous, low power flashy thing repeatedly as the shutter moves across the image plane. Instead of getting one nice big pop of power from the flash, you get a whole bunch of little weak pops of power. That is okay if you are shooting something indoors or in the evening, but not great if you are shooting someone outside at noon. I will confess that if you use bare flash close enough to your subject in full sun on high-speed sync you can get some decent results. But, put a standard modifier like an umbrella in front of, let's say, three of those expensive flashes you own and let me know if you are able to overpower the sun. Not likely.


Why does this matter? Well, what most "people" photographers want to accomplish is to make their subject stand out from the background. An excellent way of doing this is to darken the surroundings including the sky, if there is a sky in the picture. It just looks cooler, the client loves it and it is a look that screams professional.
Notice the photograph below. I do not usually do weddings but this day was an exception. And of course, they had to have a picture on this fence at 12:30 PM. Oh well, time to pull out a few extra flashes.
This image shot on D7000 with off-camera flash @ F11 and 1/400th of a second shutter.
I used a wide-angle lens in this photograph. I was standing about 8 feet away from my subjects. As a key light, I used three 1/4 CTO gelled Lumopro LP160 Speedlight's at full power on a light stand behind a shoot through umbrella. (keep in mind that both the umbrella and the gels take away power from your flashes.) The light stand was about 8 feet from my subjects. To trigger my flash I connected a Cybersync radio trigger CSRB (same thing as a PocketWizard) to one of the flashes on the stand.  The other two flashes are slaved. On the opposite side, I had one LP 160 at full power as fill. By the way, the Lumopro LP 160 has one of the most sensitive optical slaves I've ever seen on any flash. And for the price, I can buy about three of them for the price of one SB-900. They are an excellent manual flash, very easy to use and have a decent recycling time of only 4 seconds at full power. I usually try to stay at one half power or below when I shoot, but this time I needed more umph.
Here is the setup for the above shot.

 I always shoot this kind of thing in manual mode on whatever camera I'm using. This time it was  a D7000. I set the aperture at f/11 and my shutter speed to 1/400th of a second. How could I be at f/11 if it was 12:30 in the afternoon? What you can't see in the picture is that I was taking advantage of a tiny bit of shade that the palm tree was providing. Had there been direct sunlight hitting their heads, I would've added one more flash to my key and maybe would have moved the light a bit closer. "But how could you have the camera set at 1/400th of a second with flash? The D7000 only syncs up to 1/250th" you say. That's true if you have a Nikon flash connected to the hot shoe and you're not using high-speed sync. However, when using a wireless radio trigger such as the Cybersync and off-camera flash, it syncs at 1/320th of a second with no hint of the curtain in the frame! Nice! How was I able to get 1/400th of a second on this shot with no black curtain at the bottom of the frame? Notice that the ambient light is very strong at the bottom of the picture on the concrete. The ambient matched my flash output.

The setup for the bride and groom only took about five minutes lights and all.


Notice that Manfrotto 175 Justin clamps that I'm using. If you don't have any, you should get four or five. you won't know how you survived without them!

Wednesday, June 22, 2011

Quick DIY softbox grid

One of the things I love about being a photographer is I have the privilege of spending hundreds of dollars on accessories for my lighting equipment and cameras..... Not exactly. Actually it doesn't hurt to have a few carpentry skills if you are a photographer, or at least you should know how to cut cardboard with a utility knife;)
But seriously, there are quite a few things that you can do on your own, in a reasonable amount of time, that can save you some money.
What is the point?
So what's the point of a soft box grid? Well, Grids are essential in order to alter the shape and intensity of the light output from your modifier when mounted to your Speedlight or strobe.
A soft box grid will help you to center your light, making a more intimate style portrait.
As just a cut and dry example, look at the pictures here. Both pictures were taken at the same settings using a 20 inch soft box,like the one here or here, mounted on a light stand, I had a Lumopro LP160 Speedlight on one quarter power about 6 feet from the wall.

The picture on the right hand side was taken with a homemade grid attached to the soft box.
You will notice two things about the picture taken with the grid. First of all, the light is very centered and feathers out nicely. Secondly, because you are effectively blocking some of the light by putting a grid in front of the softbox, you will lose maybe a quarter to  half a stop of light.

How to build
My homemade grid in action
I'm not going to lie, this will take you about an hour to do. So if you have the money to plunk down $200 for a factory made grid, go for it. As for myself, I like to do it the six dollar way.
You will need:
Black Coroplast, black electrical tape, and a utility knife. By the way, Coroplast is basically plastic cardboard that sign makers use for outdoor signs. You can purchase Coroplast from many different places online including sign supply stores.  It costs a little more than two bucks for an 18"x 24" sheet if you buy it a piece at a time. This place sells it for $1.29 each if you buy 10. Of course you can get larger sizes if you need that. It cuts very easy with a knife but is very durable in use.
 For This soft box, I cut 10 strips of Coroplast 3 inches wide by 8 inches long. I did it using a simple straight edge and utility knife.
Now you need to cut the slots. The slots are 1 1/2" x 3/16". One slot every 2 3/4 inches.
You can see here how they're joined.

To save time cutting, you can stack three of your 3"x18" lengths together, tape them, then start cutting. ( see picture below). The slots don't really have to be perfect, as long as they're basically wide enough and deep enough you're good to go.

Pretty much all that's left to do at this point is to secure the strips together. Use a little black electrical tape or some other black tape and put a little piece on each joint ( one side only).You are basically done making your grid.
    There are a variety of ways you could attach this to your softbox. You could use gaffer's tape or maybe drill some small holes and use some 1/8" bungee cord, or you could do what I did. I decided to wrap Velcro around the ends of my grid so that it would naturally attach itself to the Velcro on the sides of my softbox. Most soft boxes have hooked Velcro on the front diffusion panel wrapped around both sides. Anyway, this worked perfect for me.
Velcro wrapped around the edge of the grid
This is how it folds up. This one folds to 30 inches long.
 So there you have it, a pretty cheap, pretty easy to build, pretty cool addition to your lighting kit.
Also, I forgot to mention that you can make snoots, gobos and all kinds of other things out of this very lightweight plasticky cardboard.

A Little Sunlight On The Subject

So many of us regularly use small flashes as strobes in our work. Just like any other tool, an SB-800 or SB-900 has it's limitations. The question constantly pops up in the forums about overpowering sunlight. What the photographer should not forget though, is that the big light in the sky makes a really good main light for your subject. It's just a matter of doing proper set up and picking a location with enough natural diffusion for the light. With the sun as the main light, you can very easily use one or two off-camera flash to work as fill light and hair light, both of which small flash can do easily at less than 1/2 power.

Check out this video from Bert Stephani. It is a good example of not ignoring the sun.


Friday, June 17, 2011

A Better Grid Hack



I'm sure many of you have learned the advantage of using grids for your off-camera flash. There are a few companies that make them for small flashes including Honl Photo and Opteka. The Opteka ships with a velcro speed strap which is nice. Honl photo sells a speed strap separately. Either way, in both cases you have these Velcro flappy things that you're supposed to attach the grids with from the sides. It's a pretty clunky way of trying to attach them, it is kind of hard to get them on firmly and straight.
 So, Speedlight grid really cool, installing the Speedlight grid, not so cool. There's a much better way and it's cheap and easy.
What you need:
 Drill with a 3/16 drill bit
1/8 inch size bungee cord
Two pieces of Velcro (hook side)
First of all, on eBay you can buy about 50 feet of 1/8" bungee cord for about eight bucks including shipping. Why would you want 50 feet of 1/8 inch bungee cord if you only need about 20 inches to do this hack? Because once you have it, you will use it for a thousand things. Trust me.
How to do it
You will drill your four holes through the outside casing of the grid top and bottom, the separation of the holes on each side being about 2 1/2 to 3 inches in between. Now cut yourself two pieces of bungee cord about 10 inches long each. Burn the ends with a match to stop them from fraying. Make a knot on one end, then thread the cord through both holes, leaving about three quarters of an inch of slack finish up by tying the other end in a knot.

Then, you just cut a piece of Velcro (hook side) about an inch and three quarters long and however wide you think is necessary. Wrap it around the Velcro cord and stick together, adhesive to adhesive.

Now when you install it onto the speed strap of your flash, the bungee cord will provide a slight bit of tension and hold it firmly in place. Waaay better than what the manufacturers give you!
Nice!