Light meters - do they tell you flash power?

I was confused while doing some research on light meters. I'm highly considering buying a Sekonic L-358, as I'm getting more and more into strobes.

I understand a incident meter reading from a light meter tells you what your exposure should be for a perfect exposure, but does it take into account the power of the flash? For example, I know I can input the aperture and ISO, or the shutter speed and ISO, and it will spit out one or the other depending on the mode that the meter is in. But does it tell you what power setting the strobe should be at in order to achieve a proper exposure?

Or, say, in a situation where I want low ambient light, but a lot of fill flash (think dark background, bright subject), will it tell me the flash power I'd need to achieve that, or am I thinking a little too much about it?

quadwing wrote in post #17059533
I thinking a little too much about it?

yes.

or not enough.

distance from light to subject, and the type of light modifier play a huge part in this equation. Not to mention the huge range of strobes and flashes, there is no practical way a light meter could factor all this in.

also, the light meter does not give you the numbers for a perfect exposure, it gives you the numbers for exposing to middle grey. You have to decide what the perfect exposure might be.

Yes, the 358 will measure your flash. It'll even give you the % of flash vs. ambient in your exposure.

For strobes, you'd set the ISO and shutter speed (usually sync speed) and the meter will tell you the correct aperture. It doesn't tell you "use 1/16th power" since it doesn't know anything about your strobe. If the aperture it tells you to use isn't want you want, you'll need to adjust your strobe power as necessary.

hes gone wrote in post #17059544
=he's gone;17059544]yes.

or not enough.

distance from light to subject, and the type of light modifier play a huge part in this equation. Not to mention the huge range of strobes and flashes, there is no practical way a light meter could factor all this in.

also, the light meter does not give you the numbers for a perfect exposure, it gives you the numbers for exposing to middle grey. You have to decide what the perfect exposure might be.

So basically, it gives me a reference point to go from? Like, "Here's the general area you want to be. Work with it."

quadwing wrote in post #17059573
So basically, it gives me a reference point to go from? Like, "Here's the general area you want to be. Work with it."

sort of. Generally you should already know what aperture and iso you want to shoot at. You set your iso and shutterspeed in the meter and then test the light. The meter will tell you what aperture will expose correctly for the level of light. Adjust the light until you get the desired aperture.

Figure out what part of the scene you want to be "correctly" exposed, meter from there with the meter aiming towards the light. The process is very quick when working with remote controlled lights.

Another thing to remember, when using your meter remember that 2 1/2 stops up from "correct" will render white and 4 1/2 stops down will render black. Knowing this will allow you to test light falloff and determine where your highlights and shadows will be before you ever even fire off a shot. You can also use the meter to ensure even coverage over a background or to find the hotspot of your light when aiming at a subject, to make sure you're not metering outside of the brightest part of the light. Imagine using a beauty dish, metering at the chin, and the forehead keeps coming up overexposed, using a lightmeter you can quickly find the "hotspot" and put it where you need it.

http://www.youtube.com​/watch?v=f3CTJJ2uVyg

quadwing wrote in post #17059573
So basically, it gives me a reference point to go from? Like, "Here's the general area you want to be. Work with it."

sure. But of course it depends on what you are shooting. My biggest use for my handheld light meter is testing in studio for product photography. In that case I want the exposure as close as i can get it to "perfect". I also include my color checker passport and test the grey values before i place the first product.

i get the impression there aren't many product photogs active in the lighting forum.

for a portrait, or fashion, or even some types of product shots you have a lot more latitude. Artistic vision, so to speak. So you take a meter reading and say, "Hmm, i want that light a little under, and that light a little over."

in a shot with more latitude, and controlled ambient, i would go into it with the camera settings in my head and then use the light meter to tell me where the power levels of the flash should be. The opposite being, testing the lights and then setting your camera to match.

quadwing wrote in post #17059533
I was confused while doing some research on light meters. I thinking a little too much about it?

I use an L-358 light meter to balance my speedlights with ambient light, or when using only speedlights.

For the former, I take a meter reading of the ambient light and then set my speedlight to the settings on the light meter. Take a shot, and tweak my speedlight power if necessary to get the look I want.

For the latter, I meter each lighting group separately ( A group, key light; B group, fill light; C group, rim/hair light) and set each aperture as directed by the L-358. I then turn on all the lights, take a meter reading, and set my aperture as directed by the L-358. I normally get a "perfect" exposure that way.

This works well for me. I'm a hobbyist, and by no means a pro.

quadwing wrote in post #17059533
I was confused while doing some research on light meters. I'm highly considering buying a Sekonic L-358, as I'm getting more and more into strobes.

I understand a incident meter reading from a light meter tells you what your exposure should be for a perfect exposure, but does it take into account the power of the flash? For example, I know I can input the aperture and ISO, or the shutter speed and ISO, and it will spit out one or the other depending on the mode that the meter is in. But does it tell you what power setting the strobe should be at in order to achieve a proper exposure?

Or, say, in a situation where I want low ambient light, but a lot of fill flash (think dark background, bright subject), will it tell me the flash power I'd need to achieve that, or am I thinking a little too much about it?

Ummmm,, no.

In my opinion you are over thinking this. What a flash meter will tell you is the aperture required for the relative distance from flash to flash meter.

I suppose you can kinda work backwards as Guide Number (flash output) = Distance x f-number.

quadwing wrote in post #17059533
I was confused while doing some research on light meters. I'm highly considering buying a Sekonic L-358, as I'm getting more and more into strobes.

I understand a incident meter reading from a light meter tells you what your exposure should be for a perfect exposure, but does it take into account the power of the flash? For example, I know I can input the aperture and ISO, or the shutter speed and ISO, and it will spit out one or the other depending on the mode that the meter is in. But does it tell you what power setting the strobe should be at in order to achieve a proper exposure?

Or, say, in a situation where I want low ambient light, but a lot of fill flash (think dark background, bright subject), will it tell me the flash power I'd need to achieve that, or am I thinking a little too much about it?

This guy explains using a Sekonic Meter and Ambient Light mix like a CHAMP.....
It's an hour long video but it's so informational that it keeps you captivated and it goes by smoothly.

https://www.youtube.co​m/watch?v=022pa16NC5E

.

The Loft Studios wrote in post #17060378
This guy explains using a Sekonic Meter and Ambient Light mix like a CHAMP.....
It's an hour long video but it's so informational that it keeps you captivated and it goes by smoothly.

https://www.youtube.co​m/watch?v=022pa16NC5E

.

Just sat through the full video, absolutely worth it. Thanks for the link

Set your light, meter. See what the meter says. If you don't like what the meter says, turn the light up or down, meter. See what the meter says. Rinse and repeat until the meter reads what you want it to read. Eventually you'll gain enough experience with your particular lights to know what kind of power they put out and can get in the ballpark to start out so it's not as much trial and error dialing them in.

But no, a meter has no idea how powerful your lights are so it can't tell you "hey, set it at 1/2 power to get what you want." Half power on a big, powerful flash isn't the same as half power on a smaller, weaker flash.

fivegallon wrote in post #17061103
Just sat through the full video, absolutely worth it. Thanks for the link

Same, great video!

@cdifoto, that probably made the most sense to me. Thank you!

The meter has no idea if it is the worlds weakest flash two inches from the meter, or the worlds strongest flash 276 feet from the meter. Both MIGHT give the exact same reading on the meter.

Enjoy! Lon

When I have the time to use my flashes on manual and use my meter I would not choose any other path. No guess work and it tells me what my flash power should be.

digital paradise wrote in post #17062952
When I have the time to use my flashes on manual and use my meter I would not choose any other path. No guess work and it tells me what my flash power should be.

No it doesn't. It tells you what your exposure settings should be at a given flash power, but it does not tell you what your flash settings should be at a given exposure.