Today I recieved a free exposure meter, and I think it's a nice one but I haven't got a clue how it works.

When you set it at for instance 800asa the apendutures below 8 are not beneath the display in wich the meter needle shows. So how can you than read it for low apendetures? (somehow the asa is connected with the apendetures and the exposure time is the variable)

And how is it's reflective mode? Does it measure all light that comes in or can you just point it at someones face to show the light the face reflects? (You can slide the white dome aside, so I suppose that's for reflective reading.

Anyone who knows what type of battery replaces the px13? I've visited some stores and the battery type is discontinued but they both didn't know and couldn't find one that still works in the sixtar.

Thanks a million for any advice in advance