You are watching Digital Photography One on One, where we answer your questions. Here is your host Mark Wallace.

Hi, I am Mark Wallace and you are watching another episode of Digital Photography One on One. In Episode 1, I showed you how the shutter works and how you can balance flash and ambient light. Well, since that episode was posted I have had hundreds of emails from people asking me to do a better job of explaining the metering portion of that video. Well, that is what this episode is all about, learning how to use your lightmeter to determine the balance between your flash and ambient light.

In this video I am going to be using the Sekonic L758. And the reason for that Sekonic has this really neat feature that shows you the exact percentage of light that is coming from your flash. So, this will work with the 758 or if you have an L358, the same thing will work. It is very common on both Sekonic lightmeters. The other thing I am going to do a little bit differently in this video is instead of using a studio strobe I am going to be using an on camera flash. I will be using my Canon 580BX. Now, I have asked Caroline to come join me and help me demonstrate this technique. We are going to be shooting in an office space that has really nice light coming from the side and we are going to be using some fill flash to balance out that light. So, let us get going.

We are in this office and we have some really nice light coming in from the right side of the room. Now, although this light is really nice we do not have light coming from the opposite side of the room. That means that if we take a shot with Caroline the left side of our face is going to be a little bit dark. Now, for this episode I am going to assume that you know a little bit about basic exposure and the relationship between ISO, aperture and shutter speed. If these are new terms to you then I highly recommend that you read the book Understanding Exposure by Bryan Peterson.

Okay, the first thing we need to do is set up our camera and our flash. For complete exposure control, we are going to set our camera to full manual mode and at this point just leave your flash turned off. Once that is set, we are going to take a basic ambient light reading. Now, this will just help us understand, give us a starting point and helps us understand what kind of ambient light we have. If the ambient light is low then we will know that either a tripod or a higher ISO is going to be needed.

Now, I like to start out by metering at a 60th of a second to see if there is enough ambient light to support that shutter speed. And if there is not, well I know I either have to increase my ISO or just be satisfied that there is not going to be as much ambient light in the scene as I would like. So, let us give it a try. I will set my meter to ambient mode, select shutter priority and set my shutter speed to 1/60th of a second. My ISO is at 100. I am using a lens with a maximum aperture value of 2.8, so if my meter reading is below 2.8 that means I cannot shoot at ISO100 and a 60th of a second. Now, ideally I would like to have my reading to be a 60th of a second and around F6. Now, F6 is totally subjective. I just like that because it gives me a nice depth of field. So, let us take a meter reading and see how these things all come together.

All right so let us take our first meter reading here. So, I am going to point this directly at the camera, take a reading and this is 60th of a second at 3.2 at ISO 100. So, really I want to have my aperture value to be a little bit smaller from my depth of field. So, what I can do here is I can make adjustments in the meter to see how that impacts my exposure. So, I am going to push my ISO button and I am going to increase my ISO until I see around F6. So, here we go at ISO400 my meter is saying well that would be a 6.3 aperture value which is about what I want. So, just to make sure I am going to take another meter reading here and it is telling me 60th of a second at 6.3 and my ISO is 400. So, let me set up my camera to these settings and we will take a test shot here to see exactly how that looks. We had the 60th of a second, our aperture value is 6.3 and our ISO was 400. Okay now that that is set remember my flash is off and we are just doing this to get a nice starting point to see what our ambient light looks like.

So, let me take a quick test shot and we will take look and see how that looks. Okay and let us look right this way, great Caroline, look right at me, excellent. Okay, this image looks pretty good, but it is just a little bit dark on the right side of the image. So, let us add a little bit of fill flash to serve even things out. Now, it is time to turn on your flash. For total exposure control make sure that you have your flash set to manual mode. I am going to start with—I am going to set this flash to about an eight of its total power. And we can adjust that up or down as we start playing with the exposure. I will show you that in a little bit. And the thing I am going to do here is instead of having my flash pointing straightforward I do not want to blast Caroline, I am going to raise this, so it bounces off the ceiling and gives us a nice soft fill flash. Well, that would be a much more flattering to Caroline and give us so much more realistic look to our exposure. Now, it is time to take our combined flash and ambient light measurement. Now, to do this I am going to set my Sekonic lightmeter to the Auto Reset Cordless Flash Mode. And I am doing this because I am using an on camera flash and there is no way for me to use a same cable to connect from my meter to my flash to trigger it. So, what this allows me to do is I can press my measurement button, the meter weights up to 90 second for a flash to fire. Once the flash fires it gives me the correct read out then I can look at that which is really cool if you do not have something to connect your flash to your meter.

Okay, the other thing I want to do is to make sure that my meter is set to the same settings as my camera. So, I know my shutter speed is at 0th of a second and my ISO is at 400. I have set that up. I have it on the right mode. And I want to come back here and I have Caroline to press the measurement button then I am going to trigger the flash. So, if you could press that. I am going to come over here and I am going to press the test button here. Now that is fired. Now, we have a reading. And the magic of this meter is that this will not only give us the correct meter reading, but it tells us exactly what the percentage of the flash is. So, this is telling me that my meter reading is at 1/60th of a second at F8 and I have 40% of the light is coming from my flash. Now, I would like to have 50% of a light coming from my flash. So, all we need to do is just increase the power of my flash just a bit and we will have that nice even match ratio. So, let me do that I am going to come over here and change this from a 1/8 up to a 1/4. I am going to have Caroline again push this measurement button. Once she does that I will fire the flash, that is fired. And now, we have exactly 50%. The Sekonic is telling us that we already have a shutter speed of a 60th of a second, F10 and we have 50% of the light coming from our flash. So, let me set my camera to those meter readings and we will take a picture and take a look and see what it looks like. Caroline?

Okay now, the really cool thing is that the meter will do all the calculations for us now once we have our initial reading they will calculate anything for us if we want to change the ratio of flash to ambient light. So, right now we are at 50%. But let us say I wanted to go up to 60 or 80% flash. Well, all you need is use the jug-will and change the shutter speed. And when I do that as I go up in shutter speed up in the upper right hand corner it is saying 60%, 70%, 80%. Now, let us say we wanted to do the opposite. We wanted to have less fill light. So, what I can do is I can take my shutter speed and roll it back. I am going down and I want to hit 20th, 15th of a second. My meter is telling me that now only 20% of the light is coming from the flash, so it does all of the balancing for you and it will tell you exactly how much light is coming from your flash in each exposure. It is really, really cool. So, let us try this. Let us try one of 20% and we will try another one at 80% and we will take a look at those.

Well, that is about all there is to it. It really comes down to three basic steps. Step one, take an ambient light reading and then adjust your camera accordingly. This will give you a great starting point. Step two, turn on your flash and take a new meter reading. Then adjust the output of your flash up or down metering along the way until you get the perfect balance between flash and ambient light. Step three, use your Sekonic meter to automatically calculate shutter and aperture values for new ratios between flash and ambient light. The Sekonic meters make that super easy with the percentage output right here on the meter itself.

Okay well, that is all we have time for in this episode. Remember, if you have a question you like us to answer, send it intostudionlighting@gmnail.com. I will see you next time.

This episode is brought to you by snapfactory.com and studiolighting.net.