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Bazil

Depth Of Field

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Here is a quick explanation of why Depth of Field occurs

 

The reason why a smaller apeture creates a larger depth of field is because the smaller the apeture, the more concentrated the light is as it goes through the hole... A pin hole camera has a huge depth of field because the hole is tiny... A camera with an apeture of infinate "smallness" (really really really really really really really really really really small ) will have everything it picks up, perfectly in focus (stuff that's miles away (if you could see that far) would all be in focus.

 

It works like this because when the light enters the hole (apeture) it has less option to not fall on the ccd/point of focus and therefore is concentrated on exactly the right place. However, if a camera is setup with f2.8, the light can shine onto otherparts (inside the camera) without hitting the CCD... To compensate, you stick a lens infront of the hole and this therefore helps to perfect the focus, but, as we all know (from using cameras and our understanding of focus) it's not perfect and thus depth of field is created.

 

I hope I worded this alright! I'm sorry if some of you didn't understand, but that's pretty much the jyst.

 

Bazil

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so is it better to have it set at f2.8?

I heard that you should try to never go over f5.6, so yes, f2.8 would be good.

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There is no "better", it just depends what effect you want to create using your apeture... If you want a longer depth of field, go higher (f8, f11 etc etc). But for less depth of field go for the lower f numbers.

 

It's not whether it's better, it's just whether you want high dop or low dop.

 

Bazil

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oh would it be great if i could set the aperture on my cam ;-)

but this was a good explanatation!

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Errr, what camera do you have? You should be able to adjust the apeture on any camera.

 

:D

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To make it less confusing.

 

If you want more of your overall picture to be in focus, chose a "higher" aperature.(like f8, f9.6, f11, and up)

 

If you want less of your overall picture to be in focus, (like a head shot in focus with the background and foreground blurred) chose a "lower" aperature. (like f2, f2.8, f4)

 

 

If you are shooting "long lens" then it really depends on what effect you are going for.

 

If you are shooting wide angle or fisheye, you genrally want more of the picture in focus, set a "higher" aperature, like f5.6 and up. This will make your shot look a lot better and less bland.

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Errr, what camera do you have? You should be able to adjust the apeture on any camera.

 

:D

i can't do it on my shitty TRV-250 but i think what you mean on any 3-ccd camera

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No, I mean on any camera.

 

You should be able to manually adjust some kind of exposure on the camera... My JVC GR-DVL767 has manual controls for apeture and shutter speed (limited), it's not graded by F-Stops, just numbers from -6 to +6. It's a basic feature on pretty much all cameras.

 

Bazil

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so in order to go from making the background in focus and the foreground blurry to the opposite you change the appeture from higher to lower, but i thought changing the appeture just over/underexposed the shot, b/c when i messing around w/ my vx1k appeture thats all that seemed to happen, was over or underexposure.

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yes, but you have tools that will affect the light, such as the nd filter and changing the shutter speed.

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so in order to go from making the background in focus and the foreground blurry to the opposite you change the appeture from higher to lower, but i thought changing the appeture just over/underexposed the shot, b/c when i messing around w/ my vx1k appeture thats all that seemed to happen, was over or underexposure.

No, it won't do the opposite, it will just make more things in the frame in focus. What I mean is that narrowing the iris (increasing the f number) will make your background in focus and more things in the foreground in focus too, depending on how far you're zoomed in if you're zoomed in at all.

 

Yes, the primary use for the apeture setting is to expose your shot correctly, but it is used for depth of field also. So, if you wanted a short depth of field on a really bright sunny day, you'd increase your f number, put your ND filter on and, if it's seriously bright, increase your shutter speed. That will give you the desired effect. On the flip side; if you wanted to increase your depth of field, you would increase your f number (narrow the iris), leave your ND filter off and, if it's a pretty dark day, decrease your shutter speed. However, it's not really worth ruining your shot with a slow shutter speed just to increase your depth of field... However, if there's enough light, you might not have to alter the shutter at all.

 

The best way to learn is to play around in a well lit environment where you can adjust your apeture settings whilst keeping everything pretty much correctly exposed. That way you can see properly how it works. Eric (from interlaced/de-interlaced) did a very good video that showed these differences with the f numbers in as titles.

 

Bazil

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if it is too freaking bright outside, try not to higher the shutter speed, but leave the shutter speed low and throw some nd filters on

 

this will make a close object be on focus while the background will be blurred or darkened

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if it is too freaking bright outside, try not to higher the shutter speed, but leave the shutter speed low and throw some nd filters on

 

this will make a close object be on focus while the background will be blurred or darkened

You could do both, you'd wanna higher the shutter speed and turn on the ND filters if its really bright out to get that desired look of the foreground in focus and background blurred.

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Im kinda new with Manual settings, So just to film on a bright day, i would use s1/90 f3.4 6db

 

but ive noticed some shots dont look the best quality,i have a Gl, this guy told me to use the sutter as the exposer, and keep the Aputure around f3-4.. donno if its right or not..

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this guy told me to use the sutter as the exposer, and keep the Aputure around f3-4.. donno if its right or not..

It just depends on what DoP you're looking for!

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Eric at Interlaced did a great video of it, but I don't know the URL and it's not on this computer.

 

Bazil

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me and garrett are in a photo class together in school. it helps alot understanding manual controls and settings. we just started so i am not very experienced with the settings. but later on i could help people on this site. which im sure bazil has it covered.

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