Quote Originally Posted by arri View Post
Here´s another sample I made with the 250mm single meniscus lens, star shape aperture f/8
Yellowgreen filter -1
Tetenal Work enlarging paper, 18x24cm size.
Ratio 2:1

Stunning!
How do you calculate the f/8 aperture with a homemade star shaped aperture? Do you measure incident light on the groundglass or use the math to determine the exact number? Just curious...