100/120 coverage diffusers?

[deeper thoughts]

My new strobe came with both diffusers and don’t understand which situations are best suited for each.
Thnx

 

[RyanT]

The diffusers spread the light out over a larger area; the downside is that you get less light directly in front of your lens. If you're shooting with a wide-angle lens, you'll need to spread the light out, however, to cover the angle of your lens. If your angle of view doesn't exceed 100 degrees, there's no need to use the 120 degree diffuser, you'd just be wasting light outside the area the lens sees. If you need wider than 100 though, you'll need to use the 120 degree diffuser.

 

[bvanant]

In general for most photos use the 100.

Bill

 

[deeper thoughts]

The diffusers spread the light out over a larger area; the downside is that you get less light directly in front of your lens. If you're shooting with a wide-angle lens, you'll need to spread the light out, however, to cover the angle of your lens. If your angle of view doesn't exceed 100 degrees, there's no need to use the 120 degree diffuser, you'd just be wasting light outside the area the lens sees. If you need wider than 100 though, you'll need to use the 120 degree diffuser.

Thnx here in the Keys I rarely use wide angle, so 100 will be fine

 

[Ardy]

Hi Guys, sorry to butt in but just a simple question - is there a major downside to NOT using a diffuser for macro? I have them on both flashes but always wondered about diffusers and the effectiveness of them.

 

[RyanT]

@Ardy, not really. It's possible that in some circumstances the diffuser might help eliminate some hot spots. But in general, you need a lot of light for macro because you're stopping the lens way down for depth of field. The diffuser is just going to throw a lot of light outside your macro lens's coverage area. In other words, it's going to waste useful light that you may need when your lens is stopped way down.

 

[Ardy]

Thanks Ryan, I have been wondering about this for a while. It's important if you want a black background using a high Fstop.