Sekonic Meters & Canon Speedlite HSS - compatible?

I plan on using my new Sekonic L308S meter with my 430EXII in HSS mode. A photographer friend "said" it doesn't give accurate readings in HSS mode due to the flash being a burst of multiple flashes....

Is this true?

It's only going to read the first pulse so I don't think it can give you an accurate reading on the overall illumination being laid down by subsequent pulses.

In ETTL, the meter is usually fooled by any preflash as well.

FlyingPhotog wrote in post #12428159
It's only going to read the first pulse so I don't think it can give you an accurate reading on the overall illumination being laid down by subsequent pulses.

In ETTL, the meter is usually fooled by any preflash as well.

really? So i can only use it below 1/250 SS

maaaaaaaaaan......

Not sure about 308 but 358 and higher up can read the flash in eTTL mode. Robert showed how all this works in his thread. I haven't personally tried it yet.

As a rough rule of thumb, if you take a reading at your max shutter sync speed then you lose approximately 3 stops of light for the first stop you go over the max sync speed and then another 1 stop of loss for each additional stop of increased shutter speed.

When I took actual measurements I determined that with my meter, camera and flash, I lost -2.7 stops for the first stop of increased shutter speed and -.9 for each additional stop.

So, if you're shooting at f/8 and 1/250s, and then increase your shutter speed to 1/500s then you're losing about 3 stops of light and you're going to have to adjust your ISO and/or shoot at f/2.8.

Any flash meter is not suitable when the flash is on ETTL.

yogestee wrote in post #12429838
Any flash meter is not suitable when the flash is on ETTL.

You need to go back read Robert's thread. Wish I had the link handy. Suprisingly you can meter eTTL flash. Now eTTL flash by its nature might change flash output from one flash to the next.

TMR Design wrote in post #12429498
As a rough rule of thumb, if you take a reading at your max shutter sync speed then you lose approximately 3 stops of light for the first stop you go over the max sync speed and then another 1 stop of loss for each additional stop of increased shutter speed.

When I took actual measurements I determined that with my meter, camera and flash, I lost -2.7 stops for the first stop of increased shutter speed and -.9 for each additional stop.

So, if you're shooting at f/8 and 1/250s, and then increase your shutter speed to 1/500s then you're losing about 3 stops of light and you're going to have to adjust your ISO and/or shoot at f/2.8.

Rob,
I'm confused... so can you, or can you not take a reading when shooting at shutter speeds of say 1/800 (outdoors, wide aperatures). The speedlite puts out a short burst as you know... does this not play nice with the meter?

bobbyz wrote in post #12429858
You need to go back read Robert's thread. Wish I had the link handy. Suprisingly you can meter eTTL flash. Now eTTL flash by its nature might change flash output from one flash to the next.

I'm always looking to learn but how is this possible if the pre-flash trips the meter before the flash actually fires?

Is there a setting on the 358 that tells it to ignore the pre-flash?

^ i'm not quite sure what pre flash your talking about?

my original question is specific to using a speedlite, at high SS triggered by pocketwizards (noteable, I use an AC3 and always have it in M mode, not A)

i never see a pre-flash pop when shooting like this...

m.shalaby wrote in post #12430289
^ i'm not quite sure what pre flash your talking about?

my original question is specific to using a speedlite, at high SS triggered by pocketwizards (noteable, I use an AC3 and always have it in M mode, not A)

i never see a pre-flash pop when shooting like this...

If you shoot in ETTL you never see a pre-flash either, but it still exists (happens too quickly to pick up on it).

You can only meter at the max shutter speed of your light meter. In the case of the Sekonic L-358, L-558R and L-758DR, the max shutter speed is 1/1000s.

With your flash in high speed sync mode and the camera's shutter speed set at max sync speed, set your meter to that shutter speed. Take a reading. It works.

Now increase the shutter speed by 1 stop (from 1/250s to 1/500s) and take a reading. That reading will be between 2 and 3 stops lower than at 1/250s.

Increase shutter speed by another stop (from 1/500s to 1/1000s) and take another reading. That reading will be about 1 stop less than at 1/500s.

Even though you can't go past 1/1000s on the meter, you can calculate exposure based on the ~1 stop loss that occurs for each full stop of increased shutter speed.

Thanks Robert for clarifying it again.

bobbyz wrote in post #12428404
Not sure about 308 but 358 and higher up can read the flash in eTTL mode.

NOT!!!

There is absolutely no handheld light meter that would be at all useful with ETTL flash systems. Even if you could measure the light output from a flash that is in ETTL mode, there's absolutely nothing you could do to use the reading to make a setting.

If the Speedlite is in full manual mode along with the camera, then a handheld meter can be useful.

SkipD wrote in post #12430535
NOT!!!

There is absolutely no handheld light meter that would be at all useful with ETTL flash systems. Even if you could measure the light output from a flash that is in ETTL mode, there's absolutely nothing you could do to use the reading to make a setting.

If the Speedlite is in full manual mode along with the camera, then a handheld meter can be useful.

Sorry worng choice of workds on my part, I meant HSS Mode not eTTL mode. But even in eTTL mode if using AC3 with mini/flex you can make exact changes in power settings just like manual flash.