Help With Metz 45 CL 4 Please

[Lyrrad]

Hi

I am a novice in this department, so all help will be gratefully appriciated.

I have recently purchased a secondhand Metz 45 CL 4. Following the instruction booklet seems quite straightforward, but I have the following problem/query.

I use a Sekonic Dualmaster L-558 that has the ability to wirelessly take flash exposure readings.

The metz GN for ISO 100=45

If I set the Metz to manual mode and use GN/distance I get a reading on my meter that makes perfect sense. So for example at 4 metres I get around F11 on the meter at ISO/100

However, if I then change my Metz to automatic mode and set it at F11, the reading I get on my meter is around F5.6.

Am I missing the point or should my Metz be delivering a reading to my meter of F11 in Auto mode when it is set to F11 itself and at 4m range.

I would also add that when set to Auto mode the auto check indicator seems to illuminate correctly (F16 on Auto will not illuminate the auto check at 4m, but F11 will)

Thanks in advance


Darryl

 

[Lyrrad]

Sorry to waste peoples time, but I suppose it's worth posting.

I just found this on Sekonic Forum



'Also, make sure that your flash is set in a fully manual mode. An "auto thyristor" or "TTL" metered flash cannot and should not be read by a flash meter.'


I assume this is the reason my readings are meaningless on Auto


Darryl

 

[127]

I'd think sekonic's warning is a little harsh - of course it CAN be measured. Whether is SHOULD be measured depends on how you interpret the results. As the results will be different it's simplest for them to tell you not to bother.

The difference is that in auto mode the flash is measuring the REFLETED light, so it puts out enough light to place your test subject at mid-grey. The sekonic meaures the light, and gives the value that would be reflected by a grey card.

If you used a perfect grey card as your test subject, the results should match up. If you used a white subject, then lots of light will be bounced back and the flash will put out less power (so the meter wil read lower).

Simlarlt if the subject is dark the flash will put out more power to get the same light bounced back.

The readings are different, because they're measuring different things. In a perfect test environment they'd probably match up.

Ian

 

[Lyrrad]

Ian

Thanks

It's always nice to know why


Darryl