Purpose for using a lot of filters

[govindaBLU]

within a digital medium?

I know that some filters are needed sometimes like ND filters, but sometimes I see people who put multiple 4x4 filters infront of their cameras. What would be the added advantage of this when you can easliy achieve this with a digital filter in post? is there an asthetic reason for this that I am missing? Or is it just simpler for some people to view the filter color ON SET while filming

thank you

 

[scharky]

I guess that depends entirely upon what filter you are using, as not all filters can be reproduced perfectly in post. I guess it also depends on the camera operators background, as far as what they are used to using when shooting. One of the biggest benefits of doing things optically is that you never have to render it. However, you do lose the option of changing your mind later. So basically, it just depends on your style as a photographer.

 

[oneinfiniteloop]

Here are two filters that are indispensible in the field for digital video, especially DV.

1. Polarizier, cuts out unwanted reflections from non-metallic source, i.e. water, glass, etc... They also help with saturation and contrast, especially in the sky.

2. ND Grad filter. These are very handy at bringing your contrast in exposure down to decent range that can be captured while retaining detail. Say if you have an outdoor shot that has a bright sky, but you're exposing for your actors, the sky will probably get blown out, losing all detail. With a ND grad, you can retain the detail in the sky by gradually stopping it down while fading to clear where your actors are.

 

[profnoxin]

Additionally, almost anything you do to alter your image in a digital post environment introduces some sort of unwanted noise. You are tweaking the image as it existed in the capture medium, and this is never preferable if you make up your mind during production.

Mist filters, such as black pro mist, soften up the hard edges of the image, and they alter the flaring/clipping charactersitics of hot spots in the frame, as well as creating glowing orbs in place of lens flares. This effect can be created digitally to a certain extent, but it takes a lot of image manipulation, and it will look mildly similar at best.

Fog filters and Contrast softening filters are the same way. Actually, nearly every filter that falls under the Tiffen category "FX" or "Effects" cannot be accurately replicated in a sub $100,000 dollar color correction/effects system accurately, and without unnacceptable image loss.

Lastly, as stated above, grad. filters of many kinds are highly useful in capturing the image that you want, not one you will have to hope you can fix in post.

'Nuff said.