hi,

deleting the config file in /home/user/.config/lightmeter was the solution. thank you!

I thought using --purge option on reinstall will also set configuration back to default?!

here is my config file for the cam:

[Pentax K-X]
iso=100,200,400,800,1600,3200,6400,12800
speed=1/6000,1/5000,1/4000,1/3200,1/2500,1/2000,1/1600,1/1250,1/1000,1/800,1/640,1/500,1/400,1/320,1/250,1/200,1/160,1/125,1/100,1/80,1/60,1/50,1/40,1/30,1/25,1/20,1/15,1/13,1/10,1/8,1/6,1/5,1/4,1/3,1/2.5,1/2,1/1.6,1/1.25,1,1.3,1.6,2,2.5,3,4,5,6,8,10,13,15,20,25,30

and for the lense:
[Pentax 18-55]
aperture=4.5,5,5.6,6.3,7.1,8,9,10,11,13,14,16,18,2 0,22,25,29,32

[Sigma 55-200]
aperture=4,4.5,5,5.6,6.3,7.1,8,9,10,11,13,14,16,18 ,20,22

I just found a mistake, i was wroting aperature in place of aperture :-D

thank you over again