View Full Version : 1/4 or 1/2 Black diffusion/FX - any tips?
Ed Moore August 8th, 2006, 09:53 AM Hi all,
I am about to buy a load of 4x4 filters to go with my H1 and I am trying to decide what grade of black diffusion/FX to get to give the image a subtle sheen - nothing very noticeable but something to take the edge off a little. A lot of reviews mention either the 1/4 or 1/2 as the perfect accompaniment to the XL1 - I was wondering if anyone had any experience with both on the H1? Presumably on HD a lighter filter grade would be required to match a similar effect in SD? I find with the Sony 750 I use a 1/4 black promist where on a 570 I would use 1/2...
Some captured frames showing both would be very helpful!
Regards,
Ed
Jim Martin August 8th, 2006, 02:25 PM Ed-
Here at Birns, Black promist 1/4 is still the most popular filter sold. If you can, rent that plus Black diff fx 1/4, glimmerglass, black frost(Schneider), soft fx 1/2,digital fx 1/4, and maybe smoque. Some rental houses(like us) usually make you take a set (1/8,1/4,1/2,1) when you rent.....Good Luck!
Jim Martin
"At the ArcLight"
John Richard August 8th, 2006, 03:31 PM Tried using our 1/2 Black Frost Schnieder in the matte-box on the H1 and it was too strong for my taste. I'd go with Jim Martin's suggestions and no more than a 1/4 Black Frost.
HD sure ain't DV - it's like everyone says, what may have worked in front of a DV cam can be entirely different than in front of an HD cam like the H1.
Ed Moore August 8th, 2006, 05:37 PM Hi Jim, yes it does rather seem that black promist has made a name for itself as "the film look filter" - I suspect this is more out of hearsay and convention more than a result of detailed comparisons... but I can't really complain; I've used the same trick myself.
Thanks for the advice on what filters would be worth trying - I am actually a bit limited as the choice was, rent full sets of everything I wanted or buy a grade or two each of a lesser selection. I've gone for the latter so I can get more frequent use out of my new matte box.
New filter set will comprise, to get me going:
Pola
Clear > ND6 soft edge grad
1/4 Black Diffusion/FX
Ultra contrast 4
Clear > Cyan soft edge grads 1 and 5
I will probably succumb to some promists and soft FXs fairly soon just to see for myself which I prefer in any given situation, but for the upcoming job I need to just pick a look upfront and stick to it or it's going to cause me all sorts of unnecessary trouble later on :)
Robert Sanders August 8th, 2006, 06:00 PM We like the 1/4 Black Promist too. We also use a .3 and .6 ND. Also, keep in polarizer in the kit for daytime exteriors. Grads are nice if you have a lot of sky in the shots (brings the clouds out).
Steve Rosen August 8th, 2006, 06:06 PM I have a full set of 4x4.56 Black ProMists from 1/8 to 3 and have never used anything above a 1. I have 1/2, 1 and 2 SoftFX filters and never use anything above 1/2 (in fact the 2's still in it's original wrapping paper - I've NEVER found a need for it)...
I wouldn't go more than an 1/8 Black ProMist, I find anything denser really starts to look like video, and is very noticeable - when I see it on TV I always say to myself "there's someone trying to make video look like film" - if it truly looked like film, I wouldn't notice it. I have shot with the 1/8 often, but am never completely satisfied because even that light strength shows up more than I like, especially w/ 1/3" chips in HDV.
I do use a 1/2 SoftFX alot, and like it better for most things because it gives a creamy look without shouting diffusion.. I DO wish they made a 1/4 SoftFX, though, but the 1/2 is pretty good - as I've mentioned in other posts, I have an old 3x3 1/2 SoftFX that I bought in the early 90's that beats anything I've found since - but I do have a new 4x4 as well - usefull filter - it just takes the edge off.
More than you need to know, I guess, but there it is...
Steven Dempsey August 8th, 2006, 06:10 PM Don't have a 1/2 Promist but have a 1/4:
Here's a comparison without and with...
Ed Moore August 8th, 2006, 06:27 PM Thank you for that - very interesting. Even the 1/4 comes out really very strong, doesn't it?
I find it hard to pick a favourite image of the two - I prefer the way the light falls across her face in the clean version, but the promist does take away some of the more distracting bits of detail. It would be interesting to see if a diffusion/FX holds the contrast better than a promist.
Do you find yourself reaching for the promist frequently, Stephen?
John Richard August 8th, 2006, 07:09 PM You might try the H1's Skin Detail settings if you are trying to smooth some unwanted detail in the subject's skin - it would be like using a matte Promist just in the skin areas and leave the rest of the shot clean.
David Ziegelheim August 8th, 2006, 09:58 PM Indoors, I use a 1/2 Black Diffusion on a DV camera maybe 95% of the time.
Isn't the Pro-Mist different from the Black Diffusion? From the Tiffen site:
The PRO-MIST filter is exceptional
for creating a mood. Outdoors or
indoors, in broad scenics or portraits,
the Pro-Mist is excellent for toning
down excessive sharpness and reducing
contrast by moderately lightening
shadow areas without detracting from
the overall image. This is especially
useful given the contrast and extremely
sharp resolution produced by contemporary
films and lenses. Pro-Mist filters
also yield moderate highlight flare that
appears to stay close to the light source
like a halo, creating an almost pearlescent
glow around the highlights. The
Pro-Mist is often used to mute colors
and create exquisite pastel tones.
THE BLACK DIFFUSION/FX filter gives a
silky-smooth look to textured surfaces. So it does a
spectacular job of suppressing facial blemishes and
wrinkles, while maintaining a clear, focused image.
The young woman’s eyes and jewelry twined on
her wrist stay crystal clear, while her face loses the
“edginess” of the unfiltered shot. The effect is flattering,
by virtually eliminating unwanted details,
but without being dull or “fuzzy.” At the same time,
a bare minimum of highlight flare is produced. The
effect of the lighter grades is subtle, with the higher
grades becoming gradually more noticeable, all
capable of providing a beautiful image.
Pro-Mist®
This popular motion picture effect creates a special
“atmosphere” by softening excess sharpness and contrast.
It generates a pearlescent halo around highlights.
Lighter grades are useful in toning down the excessive
sharpness and contrast of contemporary film and lens
combinations.
❍ Great for portraits and scenics.
❍ Maintains focus.
❍ Often used to mute colors for exquisite pastel
tones.
Black Pro-Mist®
Offers all the benefits of the Pro-Mist filter in a more subtle
form. Highlight flares are controlled. Contrast is lowered,
but with less lightening of shadows for a more
delicate effect.
❍ Creates a soft light “pastel” effect.
❍ Delicate effect with contained highlight flare.
Black Diffusion/FX®
❍ Does spectacular job of suppressing facial
blemishes and wrinkles
❍ Maintains clear focused image
❍ Eyes stay clear and sharp
❍ Virtually eliminates unwanted details
without being dull or "fuzzy".
❍ Bare minimum of highlight flare is
produced
❍ Effect of lighter grades is subtle, with higher
grades becoming gradually more noticeable
David Mullen August 8th, 2006, 10:23 PM The Diffusion-FX filters were originally designed by Ira Tiffen to achieve the goal of "invisible" diffusion.
I sort of divide diffusion filters by "invisible" and "visible" -- "visible" meaning that they create telltale artifacts, wanted or unwanted depending on your needs. Halation (glowing around bright areas and points of light) being the most common artifact, which leads to the second one, loss of contrast.
If the goal of diffusion is simply to soften fine details and definition without any telltale artifacts, then the Tiffen Black Diffusion-FX filter is probably your best bet. But that's also the reason why I never use it -- it's a little boring. When I use diffusion, I want some degree of artifacts to add that touch of "glamour", a little glow to the image.
Diffusion works around the basic principle of throwing an out-of-focus image over an in-focus image, as opposed to simply throwing the entire image out-of-focus. Nets (pantyhose) diffuse by diffracting the image around the net pattern while allowing sharp details to pass through the gaps in the net. Mitchell Diffusion used a pattern of trapezoids etched into the glass. Classic Softs use a regular grid pattern of circular "lenslets", indentations. Soft-FX uses a sort of random pattern of kidney-shaped lenslets. This idea was refined with the Diffusion-FX filter -- a smaller (than Soft-FX) random pattern of kidney-shapes were etched into the glass. Black dots were added to reduce any light scattering that would lower contrast.
Later Tiffen came out with Digital Diffusion-FX -- which just eliminated the pattern of black dots, just to make sure that they didn't come into focus on 1/3" CCD cameras or any video camera with a lot of depth of field to the image.
At the other end of the scale, where you have diffusion that creates a lot of halation and contrast-loss, you have ProMists, White Frost, SupraFrost, GlimmerGlass, Fogs, etc. And then there are the "Black" versions of these filters that counteract some of the loss of contrast from the "mist" particles in the filters.
And then you have light-scattering filters that soften less than Fogs, like Low Cons and Double-Fogs. And then there are the filters that don't soften much at all, don't halate as much, but just lift the blacks, like UltraCons and DigiCons.
Anyway, between the visible "misty" diffusion filters like ProMist and the invisible diffusion like Black Diffusion-FX, I'd put the less-misty filters like Soft-FX and Classic Softs, which soften, have some mild halation, some mild loss of contrast, but not as much as a ProMist. In this category I'd also put Black Nets and the rare Harrison Black Dot Texture Screens.
The danger with some of these is just the pattern of the filter coming into focus when you have too much depth of field. In particular, Classic Softs have too large and prominent a pattern which can come into focus on DV cameras and whatnot, so be careful.
David Ziegelheim August 8th, 2006, 10:55 PM Are you recommending the Digital Diffusion/FX over the Black Diffusion/FX?
Also, Tiffen has the HDTV/FX which it describes as a combination of a Digital Diffiusion/FX and an Ultra Contrast. Only available in 1 through 5 densities. How does that figure into it? I was thinking of adding an Ultra Contrast; would it help combat DV compression? If it would, what strength would be appropriate for HDV and DV?
With the increase in HD production for
both TV and Motion Pictures, HDTV/FX
filters address both contrast and sharpness
issues associated with HD.
HD video is higher in contrast than
traditional film. The HDTV/FX filter takes
the edge off undesired “tack sharpness”
associated with HD. It creates a “Film
Look” by reducing contrast and also provides
subtle improvements in shadow
detail.
The HDTV/FX filter smoothes out
unwanted detail and makes people look
their best, especially when shot on HD,
without evidence of filtration.
Made of the highest quality optical glass,
HDTV/FX filters combine Tiffen’s awardwinning
Ultra Contrast Filter with the new
Digital Diffusion/FX filter.
David Mullen August 9th, 2006, 12:39 AM If the black dot pattern in the Black Diffusion-FX is not a problem for you, there's no reason to use the Digital Diffusion-FX except that it probably slightly lowers contrast, which you may or may not want. On the other hand, there's no reason not to use the Digital Diffusion-FX instead because it's easy to slightly crush the blacks if necessary.
As for whether Tiffen UltraCons or Schneider DigiCons help in creating a "film look", that just depends on how you define a film look. I've seen plenty of movies shot on film with a high-con look and if you're going for that effect, you probably don't want to use filters that lower contrast.
They lift the blacks, and in the case of the DigiCons, darken the highlights too, compressing the exposure range a little. This may give you a little more flexibility in post color-correction but it's not some cure-all. When shooting in HD to a highly compressed format like 8-bit HDCAM or DVCPRO-HD, I tend to try and nail most of the look in-camera and just leave the final tweaking for post color-correction because the compression and limited color depth will limit your ability to push around the image in post without artifacts popping up.
The thing is that once you combine a diffusion that doesn't lower contrast like Black Diffusion-FX with another filter that lowers contrast like an UltraCon, I sometimes wonder if you might as well just use a filter that softens and lowers contrast together, like a ProMist or GlimmerGlass, as long as you were OK with some halation. That's one reason why I use a ProMist instead of a Black ProMist -- increasing blacks and contrast is something I can do either in-camera or in post easily. If I jump from a 1/8 ProMist to a 1/4 ProMist and I don't like the slightly milkier look from the heavier filter, it's easy to lower the Master Video Black a little to compensate.
I find it's helpful to stop thinking about which filters give you a film look or not and just pick filters for the specific things they do to an image. If you want to use a Black ProMist instead of a Classic Soft, it's because you like the effect that the filter creates, regardless of whether that look is "more like film". If you want a low-contrast image or a high-contrast image, it's because you think one of those best serves the needs of the project.
Schneider has some new filters that combine a light Classis Soft with a light Black Frost, which sounds like a pretty effect.
David Ziegelheim August 9th, 2006, 01:11 AM David, thanks for your insights. Is the UltraCon a little like using a knee to preserve the bright sections and a black stretch to raise the dark sections?
David
Ed Moore August 9th, 2006, 04:31 AM Thanks for taking the time David, I always enjoy reading your thoughts on filtration on CML. You've read my mind as well - I was planning to try sandwiching the UltraCon with the Diffusion/FX to get the best of both worlds. I am a big fan of a contrasty look in general but in this specific instance I will be shooting in wide open fields with unpredictable weather and no chance of artificially altering the contrast ratio with lighting or grip so I want the ultracon around to help out if necessary.
I do like the ProMist halation but I need more time than I have for this shoot to test and find the right grades.
Couldn't agree more about nailing in in camera for compressed formats. I am trying to colour correct some HDV footage now and it's frankly horrific how much information simply doesn't exist anymore once it's hit the tape.
Steven Dempsey August 9th, 2006, 10:05 AM Do you find yourself reaching for the promist frequently, Stephen?
Ed, I don't use the promist very much because it's a little too foggy for me. The one I use the most for closeups is the Schneider Classic Soft 1/2. It is very subtle but quite effective in my opinion.
Here is the Classic Soft:
Ed Moore August 9th, 2006, 10:26 AM Yes, that's lovely. Much nicer than the BPM
David Mullen August 9th, 2006, 12:03 PM Tiffen UltraCons would be a little like lifting the Master Video Black slightly while also engaging Black Stretch (Black Gamma) -- not sure if you could forgoe the filter and do that only with the menu settings... but in theory, the advantage to using the filter would be that it wouldn't contribute to an increase in noise.
I suspect the best thing would be to test a combination of these techniques.
In addition to what the UltraCons do, the Schneider DigiCons also suppress some bright highlight exposure, probably with some sort of black specks in the filter. Again, compared to using the knee function or simply underexposing slightly to hold more highlight detail, probably you'd want to test a combination of approaches along with the filter.
You can see a test of the filters here:
http://www.cinematography.net/digicon-test.htm
Generally it's always easier in post to slightly increase contrast than to reduce it, because it's always easier to throw away information than recover it, especially if it was never captured. But there are limits when dealing with compressed images.
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