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-   -   Schneider Digicon Filters? (https://www.dvinfo.net/forum/techniques-independent-production/45887-schneider-digicon-filters.html)

Matt Irwin June 7th, 2005 11:51 PM

Schneider Digicon Filters?
 
Has anybody used Schneider's Digicon Filters?
They are designed to pull down the highlights and lift the shadows without any resolution loss or color shift. I asked the reps at CineGear about them and they said that when combined with in-cam gamma tweaks and/or tweaks in post, it can add up to 2 1/2 stops to a camera's dynamic range! (this is most likely with higher end dv50 or HD cams)

I'm wondering if anyone here has anything to say about them or knows where to go to test them out.

thanks

Rob Lohman June 12th, 2005 05:20 AM

Anyone worked with these?

Aaron Shaw June 12th, 2005 09:48 AM

Nope. Been wondering about this as well actually..

Jon Fordham June 15th, 2005 02:39 PM

The DigiCons are similiar to Tiffen's UltraCons. The idea is that by flattening out the image contrast you can capture a wider dynamic range. The problem is, you end up with exactly that: A Flat Image. While this approach may be useful to some who prefer the digital negative workflow, it's not a magic filter that is going to actually increase the lattitude of the camera while maintaining what most see as normal contrast.

Even in a digital negative workflow, you'll likely end up killing the small gain in dynamic range by crushing the blacks to get back to a more normal looking picture. What's worst, is that the digital negative approach adds time to the post production schedule. And time is money...

UltraCons are a great tool for some situations. But they are not a blanket fix for poor lattitude.

Gustavo Godinho June 19th, 2005 02:02 PM

Jon, it increases or not the dynamic range?

Jon Fordham June 20th, 2005 02:15 PM

Yes and no…

Let’s say that the CCD's of your DV camera have the ability to resolve 7 stops of latitude. Using a contrast filter isn’t going to magically give your CCD’s the ability to resolve 9 stops.

A contrast filter works by lifting the shadows to a lighter level. Since your shadows aren’t as dark, you can see more detail. With lighter shadows, you can now underexpose the image to bring the highlights into range and still maintain some detail in those shadow areas. So yes, you are able to capture a wider dynamic range.

However, this is an optical “trick of light”. Your CCD’s are still only resolving 7 stops. You have to remember that your contrast has been flattened to achieve the effect. So even though you can now capture a wider dynamic range, you have a very flat looking picture. Your blacks become grey, and your whole image loses “pop”.

This is the same issue you run into trying to capture wider dynamic range by electronically manipulating the camera’s DSP using flattened gamma curves, or features like “Cine-Gamma”. You can manipulate an HD camera’s DSP to achieve an exceptionally wide dynamic range. But you end up with a very flat, grey looking picture.

This doesn’t mean that contrast filters (or DSP manipulation) aren’t useful and effective tools for achieving a desired result. For those that prefer a lower contrast image, the lighter grade contrast filters will serve you well for general use. Or, for those with the time, money, experience, and patience to work in an environment where a digital negative approach is what you prefer, then the higher grades of contrast filters and DSP manipulation will also serve you well in giving you the most information to work with. But for those who like a standard, or high contrast image without sitting at a computer enhancing the contrast and waiting for it to render, then contrast filters aren’t for you.

Always bear in mind that filters are tools to be used in various situations to achieve a desired result. They are not blanket fixes for that which you don’t have in the first place. Many filters, though effective tools, have trade offs.

Gustavo Godinho June 21st, 2005 01:28 AM

Thanks, Jon!

Tung Bui June 24th, 2005 10:03 AM

I hired a set to play with for my dvx100a camera. Here's what I found.

It does lift up your blacks abit. Its suppose to compress the highlights but what I really found was that it acted like an nd filter and lower everything by one stop. To get the camera's exposure to what I thought was correct I had to open the iris up a stop. If I leave it as it is I find it alters the total mood of the picture eg if I was doing a midday shot then I want it to look like midday but if I underexpose it looks like afternoon. I also note that it brings out abit more grain that is already in the picture.

It lifts out shadow detail but your blacks arent as black anymore. I turned down the black pedestal to try to preserve the blacks somewhat. It gets rather complicated when you start making exposure and black level compensation and thats before you do stuff to it in the computer.

It is different to just simply raising your black levels in camera to lift the blacks. If you just do this then your whole picture becomes milky not just the blacks. Also lifting your exposure will raise the blacks but also blow out everything else.

The flattening out of the picture if done mildly will give you a slightly "filmic" look by reducing the contrast and harshness of the picture. You can reduce the line sharpening of the picture by turning down the sharpness in camera but it just makes the picture soft and fuzzy. I think that this reduction in contrast with minimal picture degradation is its most useful function.

Charles Papert here uses them alot and knows how to get the most of it in post but I'm not an expert on that. I tried crushing the black back abit with the curves function but it didnt improve the image that much.

Good luck

Aaron Shaw June 24th, 2005 02:55 PM

Any chance you could post a screengrab or two?

Craig Marshall September 9th, 2014 04:05 AM

Re: Schneider Digicon Filters?
 
Quote:

Originally Posted by Jon Fordham (Post 323977)
The DigiCons are similiar to Tiffen's UltraCons.

Not so. They are quite different filters. I shoot exclusively with a medium Digicon 1/2 and published some test results to this forum earlier this year. Here is the link to that article which also links to a detailed technical analysis published on the Lightworks forum which includes Tecktronics waveform and vectorcsope screen grabs. I should point out that I set my camera up to record a completely flat or neutral image first before placing the Digicon in the matte box. In my opinion, the Digicon's perform best by manipulating light prior to it reaching the sensor with any adjustment made later in the grade.

http://www.dvinfo.net/forum/sony-nex...-profiles.html Spool down to the 'Honeyeater' pictures at the bottom of the thread.

Given that most 8bit cameras really only have a 'useful' four stop dynamic range, two above neutral grey and two below, then anything a DOP can do to keep most of the light within that narrow band can be considered an advantage so the Digicon filter is a brilliant solution, especially when shooting compressed LongGOP formats, as recorded by most handycams and DSLRs. Schneider also recommend the Digicon series for high end 10bit cameras like Reds and Arris as well as 16 and 35mm film.


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