moviemaker999
Well-known member
Is it better to keep your iris open and use the built in nd filter or close the iris more and use no nd filter.
close iris or nd?
- Thread starter moviemaker999
- Start date
Vampiresoup
Well-known member
The more you close your iris the deeper your dof will be. If you want a shallow DOF, open your iris and use an ND. An ND is a neutral density filter. Doens't change the colour of your image, just lets less light in. This is my understanding anyhow. Hope that helps
Robbie Comeau
Como's back. back again
if my iris is open, and im on a tripod focusing on someone, or a subject, i get MAD noise, err!
Robbie Comeau
Como's back. back again
but if my interpreted footage is 23.98 and i conform it to its parented null objected layer, i can make a switch and loop its exponential form to a 29.97 sequence, which meens i won get any interlace, and my footage will be as a smooth as 30i but since were faking it, we just gutta parent the null layer to its individual layer to its exported RAM speed and then the processor of the ram speed will pick it up with better 1080i resolution to conform the dvx's frame rate to its original state
VeryNewMediaGuy
Member
That's a creative decision based on how great a depth of focus you'd like to create. Also, you sometimes lose a little of that vibrant color with your iris shut down tightly; if you're shooting on a bright, sunny day, yet you still want to isolate a subject from the background, that's where ND filters are indespensible and let you open your iris up and blur out your background/foreground.
Of course, there are times when the light is so intense you MUST use ND filters to keep the signal from peaking. You can only close the iris so much...
cecil995
Well-known member
what does that have to do with iris?
Without any consideration for DOF. If your outside shooting a bright sunny day, a polariser is a good will drop the exposure slightly as well, then an ND - I try to keep exposure somewhere between f3.4 to f5.6 for the sharpest image (again when DOF is not a consideration).
Gabriel Hyden
Member
isn´t it the more open your iris is the more dof you have? that´s what i thought and how it works for my footage.
Correct.
Gabriel Hyden
Member
but it´s the same with photography, just try it dude.
i just know, the more open my iris is on my cam, is it the dvx or the d20, the more dof i get.
i just know, the more open my iris is on my cam, is it the dvx or the d20, the more dof i get.
There is more to it than just controlling depth of field, aperture also greatly effects image quality.
Lenses have a "sweet spot", an aperture range (slightly dependent of focal length) in which they produce the sharpest image.
These mid-range cameras, like the DVX, have a small sensor meaning diffraction will be visible at relatively large f-stops.
I think the DVX book states that DVX performs best in the f/4.8 to f/11 range.
Lenses have a "sweet spot", an aperture range (slightly dependent of focal length) in which they produce the sharpest image.
These mid-range cameras, like the DVX, have a small sensor meaning diffraction will be visible at relatively large f-stops.
I think the DVX book states that DVX performs best in the f/4.8 to f/11 range.
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Gabriel Hyden
Member
oh thanks alot man, didn´t know about that ;-)
Luis Caffesse
Admin
Maybe there's a miscommunication going on here - but that sounds like EXACTLY the opposite of the way it works.
The more 'open' the iris is (meaning the lower the F-Stop) then the SHALLOWER the Depth of Field is.
The more 'closed' the iris is (meaning the higher the F-Stop) then the DEEPER the Depth of Field is.
Obviously there are more factors at play than just F-stop, but I just wanted to clarify that so no one hopefully got the wrong idea.
As for the original question - I completely agree with the comments about a lens's 'sweet spot' - on my HVX (and the DVX) I try to never shoot above 5.6 if I can help it - unless I just REALLY need that deep depth of field. I find that between 4 and 5.6 looks best to me, in general (again, when DOF isn't reallly a consideration).
gco
Veteran
Doesn't have anything to do with anything.
Rather than adding something helpful, he's just wasting board space.
Ditto what Luis said. He nailed it.
Luis Caffesse
Admin
I felt it had gotten answered, actually -
But - if we need a direct response, here's my attempt:
It makes no difference on image quality, if that's what you're asking, as long as you are staying on the relative low end of the Fstop range (F5.6 and below).
Now if you are talking about shooting at F11 vs using the ND filter and openign the lens more - definitely open the lens up more (unless you need the wide DOF of F11 for your shot).
Like was mentioned before - these small sensor cameras really hit their sweet spot in the middle of the lens. Unless thers is a reason for it, I'd stay below 5.6 if you can.
As long as you're in that range - there is no image quality difference between using the ND filter or not using the ND filter.
VeryNewMediaGuy
Member
DING DING DING DING DING!