Confused by crop factor when shooting wide open trying to figure out your depth of field (dof), stuff the maths just measure it. I love to shoot wide open for portraits because I enjoy the softness. When I was a full frame junkie I used a 50mm f2.8 for the most part. Now on mirrorless I shoot 25mm at f1.7 which while not the same is similar enough for my experience to directly translate. If you're confused by the maths then you're not alone. Photography is about creativity not maths. The best way to figure it out is to shoot. The objective in portraits is (often) to keep both eyes in focus when you focus on the dominant (nearest to camera) eye. This means you need to know how your lens performs. In this image I've focussed on the 10cm mark on the ruler from about the same distance I'd shoot a person (up close because I like an intimate portrait) and I see about 1cm in focus towards camera and nearly 2cm in focus away from camera. This means even wide open at f1.7 it's highly likely both eyes will be in focus. It's really important to understand your dof fall off to shoot what you want to get great outcomes instead of loads of dross and the occasional happy accident.
Note on my om-d e-m1 mk ii it's a 1.9 crop factor so this 25mm is about 46mm on ff and the f1.7 for dof is about f3.2ish but is true f1.7 for exposure (light). That's the math bit 😋.
No comments:
Post a Comment
I'll be pleased to read your constructive comments and respond