Moody Sekonic 358

[GCGuy]

I just got my Sekonic 358 from UPS this past Friday and have been using it quite a bit to get used to. For ambient light, it gives me spot on exposure readings every time. Once I started to use the remote flash feature to set exposure, however, that's when stuff got weird. I set it to auto reset cordless flash mode with the first 2 DIP switches down using my 580EX to trip the 430EX mounted on a tripod with an umbrella at 1/1 power. Pointing the 358 directly at the umbrella from about 6 feet away with the lumisphere up, I was getting alot of e.U. messages on the meter. That would indicate an underexposed setting at a 1/200 shutter speed with the 430EX set at 1/1 power, which makes no sense at all. If I turned the meter off, waited a minute and turned it back on, it would meter fine again for a few shots, then it would get stupid and do the e.U. thing again. By the end of the day yesterday it was behaving just fine, but I'm concerned about it acting up at a paid shoot.

Anyone else have this issue?

[tjongkristian]

I believe the 580EX send a command signal (flash) to trip the 430EX. The Sekonic will read that very faint/weak flash and indicate it as under exposed. What happened if you use only one flash, does it give a good reading all the time?

[tagvestibule]

I just got an L-358 and I'm having the exact same problem. Although tjongkristian's suggestion seems logical for GCGuy's setup, I had this problem last night firing a 580EX II in manual mode via a cybersync transmitter and receiver. Therefore, it wouldn't seem to be a preflash problem in my case.

Like GCGuy, it has been an intermittant problem for me. Anyone have other ideas/suggestions?

[Curtis N]

I believe the 580EX send a command signal (flash) to trip the 430EX. The Sekonic will read that very faint/weak flash and indicate it as under exposed.Yep.

[GCGuy]

I believe the 580EX send a command signal (flash) to trip the 430EX. The Sekonic will read that very faint/weak flash and indicate it as under exposed. What happened if you use only one flash, does it give a good reading all the time?

Genius! Yeah it didn't give me any issues using just the on camera flash, that just might be it.... more experimenting and need to get my cybersyncs to avoid the preflash. Thanks for the idea!!

[SkipD]

Genius! Yeah it didn't give me any issues using just the on camera flash, that just might be it.... more experimenting and need to get my cybersyncs to avoid the preflash. Thanks for the idea!!Using a meter to measure flash from ANY automated flash - whether it be a camera's built-in flash or any Speedlite (or Speedlite-based system) working in ETTL (or any of its variations) mode - is a useless effort.

All of these flash sources emit either a pre-flash pulse to calculate exposure or they communicate via flash pulses. Any of these flash pulses will be seen by the meter as THE flash output and the resulting measurement will be totally useless.

The only situation where using a meter with Speedlites (or equivalent "smart" flash units) makes any sense at all is when you can put the Speedlite(s) into totally manual operation with no communication via visible light. You should also have the camera in manual mode and you will adjust the flash units or the camera's aperture (or both) to set up your exposure.

[GerBee]

The only situation where using a meter with Speedlites (or equivalent "smart" flash units) makes any sense at all is when you can put the Speedlite(s) into totally manual operation with no communication via visible light. You should also have the camera in manual mode and you will adjust the flash units or the camera's aperture (or both) to set up your exposure.

Worth repeating that. bw!

[Agamemnon]

Using a meter to measure flash from ANY automated flash - whether it be a camera's built-in flash or any Speedlite (or Speedlite-based system) working in ETTL (or any of its variations) mode - is a useless effort.

Agreed, not only because it technically won't work, but also because you're trying to light manually with automatic flashes that will compensate for what you're doing, and do what they think is right.

What you want to do is play around with FEC (Flash Exposure Compensation) and ratios between the flashes.

[Curtis N]

In defense of the OP, he was trying to use manual flash, simply triggering the slave via the Canon wireless system. It's a nice system when it works, but unfortunately its command flash tends to confound meters.

[GCGuy]

Yeah, I did have it in manual flash mode, manual camera controls as well. I was setting the shutter at 1/200 and getting a feel for how it's gonna work when I get my Alien Bees, and to get a little practice with the meter before hand as well. Completely didn't cross my mind about the trigger flash that operated the 430EX, duh (smacks self on back of head). Gonna just have to wait for the wireless radio triggers :)