Different readings, flashmeter in reflected/incident modes

[MattKing]

Mine reads fine in incident mode - whether flash or ambient.

 

[Chan Tran]

I get a 2-3 stop overexpose (and unusable images) using incident light flash measurement.
But I get nice exposures in reflected mode.
Does it work fine for you in both modes?
Could I be missing something?
The meters works fine in ambient light. But I tried with different surfaces, and incident flash always read a much less light intensity that leads to overexpose.

To get overexposure by 2 to 3 stop with incident light meter your subject must either generates its own light or has specular reflection. You won't get overexposure even if your subject is 100% diffuse reflectance.

 

[elerion]

I do get several stops overexposed images.
As I said, if using another flash meter, I get good exposures (incident measures, all the time).
But everything else is working fine. Strange, isn't it?
Should I send it to be checked?

 

[removed account4]

it might just be a mercury in retrograde thing happening to your meter.
effects of mercury retrograde have been happening since mid march and will
still be happening towards the end of may. may 5th it goes "direct" but the shadow
will still be messing with you until the 26th or so. try your meter in june

until then ... if you have a different meter that works you might as well use that, for your ambient readings
and flash guide numbers for the flash figure out a system from there.

good luck !
john

 

[elerion]

I did some more detailed tests, and got some interesting conclusions.

In brief, when flash output power is high enough, or it is placed close enough to flashmeter, as to get apertures from f8 upwards, Lunasix F readings lead to nice exposures, very close to that of the dedicated flashmeter.
Troubles are when a good exposure requires apertures f5.6 and below.
Then, Lunasix F overexposes by 1 or 2 stops (reads f2.8 when f4 is the good one), and leads to (almost or sometimes completely) unrecoverable images.

So, the meters work perfectly, except when reading flash in incident mode, and flash requires apertures around or below f5.6.
Does it makes sense?