Better dynamic range with ND-Fader filter?

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Frank Glencairn

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Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 2:33 pm

I just stumbled over this while doing some tests.
Looks like you get better DR when using a Fader-ND filter (probably any ND Filter) than stopping down the iris.
So here is a quick and dirty test

http://frankglencairn.wordpress.com/201 ... er-filter/
Last edited by Frank Glencairn on Sun May 05, 2013 2:47 pm, edited 1 time in total.
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adamroberts

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 2:42 pm

Interesting.

Your link take me to you WP login page tho...
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Frank Glencairn

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 2:49 pm

Fixed the link, thanks for the heads up.
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adamroberts

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 2:57 pm

Interesting.

Do you think the IR filter has any impact on that test? I'm assuming you had no IR filter on the stopped down shot?

Also as the aperture in the Fader ND version is wider open the bright highlights are more spread out and perhaps not as intense?
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Hans Engstrom

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 3:43 pm

adamroberts wrote:Interesting.
Also as the aperture in the Fader ND version is wider open the bright highlights are more spread out and perhaps not as intense?


That and perhaps that the pola in the fader is doing something to your highligts.
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Frank Glencairn

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 3:45 pm

Think it works more like a lowcon filter. And yes, the IR was on it all the time, also the ND at lowest level.
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cengizözgök

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 4:02 pm

I always shoot with ND and polarizer filters together in bright day light
And the result are perfect with the dr
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Peter J. DeCrescenzo

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 5:18 pm

Hans Engstrom wrote:... perhaps that the pola[rizers] in the fader is doing something to your highligts.


I fairly certain it's 100% due to this.


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Frank Glencairn

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 9:30 pm

Hans Engstrom wrote:
adamroberts wrote:Interesting.
Also as the aperture in the Fader ND version is wider open the bright highlights are more spread out and perhaps not as intense?


That and perhaps that the pola in the fader is doing something to your highligts.


Point is, I was talking about the shadows.

Highlights are the same, but when you look at the shadows (headphones) or even lower midtones, there is ore texture, when using the ND.
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Peter J. DeCrescenzo

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 10:03 pm

Frank Glencairn wrote:
Hans Engstrom wrote:
adamroberts wrote:Interesting.
Also as the aperture in the Fader ND version is wider open the bright highlights are more spread out and perhaps not as intense?


That and perhaps that the pola in the fader is doing something to your highligts.


Point is, I was talking about the shadows.

Highlights are the same, but when you look at the shadows (headphones) or even lower midtones, there is ore texture, when using the ND.


Lowering the brightness of highlights using a polarizer will allow you to increase exposure via the aperture (thus brightening the shadows) ... or did you not adjust the aperture between tests?
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Andreas Kaufmann

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 10:40 pm

Interesting indeed!
By the way.. does it make any difference in which order you put the ND and IR on the lense?
I think the normal way of doing it is LENSE -> ND -> IR , right?
What about Lense -> IR -> ND?
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Hans Engstrom

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 10:49 pm

Peter J. DeCrescenzo wrote:
Lowering the brightness of highlights using a polarizer will allow you to increase exposure via the aperture (thus brightening the shadows) ... or did you not adjust the aperture between tests?


I also understood that you exposed for the highlights either by fader or by aperature. If there really is more information in the picture my guess is that the highlights got lowered by the pola and thereby getting more of the shadows into your DR. If there´s no more information in the shadow areas and that they just appear brighter, then it´s more likely a low contrast effect.
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Larry Sellers

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Re: Better dynamic range with ND-Fader filter?

PostSun May 05, 2013 10:50 pm

It looks to me that because all your bright areas are now way out if focus, the dark areas are blending in and making those highlights less bright. Take that along with being able to close down freely without hard stops allows a little extra light in. The lens is shutting down in 1/3 stop increments or whatever the fraction is...
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Aaron Scheiner

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Re: Better dynamic range with ND-Fader filter?

PostMon May 06, 2013 9:06 am

In my experience in-focus light sources tend to show more zebra than out of focus light sources (for the same exposure)... in this test this means that the ND filter allowed the aperture to be set to a faster value, decreasing DOF and by extension pushing the bright background out of focus, allowing the total image exposure to be increased, which brought out the texture in the headphones.

Just a guess.
-edit- Essentially what cheezweezl just said.
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Darryl Gregory

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Re: Better dynamic range with ND-Fader filter?

PostTue May 07, 2013 5:00 am

cheezweezl wrote:It looks to me that because all your bright areas are now way out if focus, the dark areas are blending in and making those highlights less bright. Take that along with being able to close down freely without hard stops allows a little extra light in. The lens is shutting down in 1/3 stop increments or whatever the fraction is...


I'm sorry this makes no sense at all, It's very simple, It is the Fader ND doing all the work as
Polarizing will do, Allowing for more control in the highlights and better range in the mids and shadows, period.

"bright areas are now way out if focus, the dark areas are blending in and making those highlights less bright"
are you sure you want to confirm that cheezweezl? because I'm confused by your logic, Sorry I'm not trying to be confrontational, just trying to understand your thought process about this.

http://en.wikipedia.org/wiki/Polarizing ... ography%29
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Frank Glencairn

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Re: Better dynamic range with ND-Fader filter?

PostWed May 08, 2013 12:26 pm

Looks like the mystery is solved, why the ND fader does that trick:

As Gerardo Campos pointed out on my blog:

The reason is very simple: is because the ND fader are made of 2 polarized filters, so when you use a polarizer you cut light from the highlights giving you more space to play in your shadows; then the 2 polarized filters from the ND Fader in first place cut the highlights and when you start to rotate it start to act in all other lights.


And here is the reason why that doesn't work with traditional ND filters:

the normal ND push down all lights equally, so shadows and lights go down; but Circular Polarized filter cut only hi light, is the best filter to obtain a blue sky and a bright terrain
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Peter J. DeCrescenzo

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Re: Better dynamic range with ND-Fader filter?

PostWed May 08, 2013 9:22 pm

Frank Glencairn wrote:Looks like the mystery is solved, why the ND fader does that trick: As Gerardo Campos pointed out on my blog ...


There is/was no mystery:
viewtopic.php?p=49845&sid=6f0301e34328096c458b0f1e522058e8#p49845
viewtopic.php?p=49882&sid=6f0301e34328096c458b0f1e522058e8#p49882

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