Manual lenses and flash

I'm using a K200D with manual lenses.
The flash will not fire unless i set it on AUTO/REDEYE-the question is this-is this what they refer to as the pre-flash mode?

I am using 'M' lenses at the moment.Flash is Metz AF36-4 -P-TTL Dedicated

thanks
Chris

No it isn't. The redeye bit does produce a pre-plash but it plays no part in the calculation of flash power or exposure.

The P-TTL preflash is used to set the flash output to produce the correct exposure for the flash to subject distance.

I've no experience of the flash you have so can't help with the practicalities of setting it up properly.

Peter, thanks for reply.
The Metz has no settings-just on/off.-I presume the flash/cam/lens aren't talking to each other with manual lenses

Regards
Chris

The K20D manual states:-

The built-in flash cannot be regulated and fully fires when pre-A series lenses or soft focus lenses are used.

I guess this might also limit the capabilities of a hot shoe mounted P-TTL flash.

Hi Chris,

Just looked at Metz website which does not mention the specific flash you have.

But in general for P-TTL to work the camera must 'know' the F stop of the lens, which it won't know if you use an 'M' series lens.

AUTO refers to a flash mode where a specific aperture is set on the lens then a sensor on the flash controls the duration of the flash for correct exposure over a range of distances.
The information on the Metz web site for the Canon/Nikon versions of the AF36-4 does not show an AUTO mode so I suspect your flash will not have one either.

These means you are left with manual flash when using a 'M' series lens. So set camera to manual, shutter speed 1/125, adjust sliders on flash for ISO and focal length (I assume its the same as the Canon/Nikon version picures on Metz website) use table on flash gun to determine from distance what apperture to use, focus at full aperture, then stop down to apperture from flash gun, take picture.

This give you a 'full blast' from the flash gun with ammount of light allowed into camera being entiely controlled by apperture.

Be carefull about using the red eye setting with manual flash as its likely that the red eye flash will be at full power leavng no juice in the flash gun for the real flash; I would just use the ordinary flash icon on the camera settings.

Of course when you aren't using the 'M' lens you can change to a non-manual mode on the camera and recieve the benefits of P-TTL

Cheers for that advice Bob.
The Metz flash has no settings though-just an on/off switch.
With a manual 'M' lens fitted, my K200D wont fire the flash unless it is set on the AUTO/RED-EYE setting.

Regards
Chris