f-stops question,

[JitCam]

hey all,


got a question, do you have better picture quality when stopped down to 2.8? or when you use a fstop of say..F11?


:beer:

 

[Charlie Anderson]

5.6 seems to be the best picture quality I've found so far

 

[Robbie Comeau]

Does this follow the DVX? I heard 4.8 is good for the DVX.

 

[Luis Caffesse]

I generally aim to shoot at 5.6 or below.

Once you get into the smaller apertures (F8, F11) you're hitting the diffraction limit of the lens,
and effectively lowering the resolution of your footage, getting softer images.

Here is one of the better explanations and examples I've found on the diffraction limit.
It's on a digital photo forum, but the principles are all the same when talking about digital video.

 

[Dick Campbell]

and the opposite end, wide open, introduces more aberrations, so there is a "sweet spot" aperture for any lens, usually a couple stops from full open. Lots of google on this.

 

[JitCam]

ok.. i had the idea that the lower the stop... the better quality.. so i was always stopping down and adding the nd filter to darken.

 

[Dick Campbell]

wel, like the guy said about sweet spots on a tennis racket - the pros don't always hit it, but they still make good shots. The point is to select the aperture for the creative shot you want, and just be aware of the trade-offs.

correct me if I'm wrong, but I recall that "stopping down" meant to close the aperture; i.e., increase the f-stop number.

 

[JitCam]

correct me if I'm wrong, but I recall that "stopping down" meant to close the aperture; i.e., increase the f-stop number.

i think so yeah, that confuses me also, when i said stopping down i meant a lower number value.. example 2.8, my mistake!

 

[JitCam]

Here is one of the better explanations and examples I've found on the diffraction limit.
It's on a digital photo forum, but the principles are all the same when talking about digital video.

luis,
nice link thanx