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kye

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7 hours ago, barefoot_dp said:

Don't believe everything you see on the internet! ūü§£ūü§£
They've even added digital lens flares to the "before" images. The picture with the sun in the frame would be exactly the same in the before/after in real life, which shows that not only are they flogging junk, but they don't even understand what their junk is supposed to do!

I didn't even look at the photos in the posting. They are probably BS, but the product is still good. I use these kind of lens hoods on all my lenses because they add very little bulk, are study enough for it's purpose (aluminium), but soft enough to dent if you drop the lens, cushioning the fall. I dont feel any need for using lens covers when I have these on with the way i store my lenses.

When it comes to reducing flare, modern lenses dont really need lens hoods the way old lenses does, but they'll still be better than nothing, and more importantly, they don't degrade image quality like UV-filters do.

 

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7 hours ago, HockeyFan12 said:

Of those three, I've used Digital Diffusion FX, HDTV FX, and Smoque.

Smoque looks to me like it's simulating filling a room with haze. Imo it's probably not what you're after.

I think HDTV FX is a combination of Digital Diffusion FX and Ultra Contrast. Or it seems that way to me, at least.

Ultra Contrast on its own is sort of like having a dirty UV filter or using a lens with light haze. It lifts the black levels like a controlled flare would when hit by light. This isn't so different from just using vintage lenses with older coatings (and internal haze and dust from age and lack of servicing), but for whatever reason I don't really like Ultra Contrast as much as I like vintage lenses. Ultra Contrast feels more all or nothing to me, a little unsubtle, or maybe I should have just used a weaker strength of it than I tried out.

Digital Diffusion FX looks to me exactly like it does in Tiffen's video series and is the closest look to whatever the Alexa has that smooths the image out. I was recently comparing Alexa and C100 footage and the Alexa has a bit of in-camera sharpening I think and also a strong, smooth OLPF. The Alexa footage looks softer when you zoom in, but maybe sharper from a distance I think? Fwiw Red Dragon also has a strong OLPF. Black Magic imo is technically great but the 6K is a little too sharp for my preferences.

https://www.youtube.com/watch?v=ryPILshPAFI

https://www.youtube.com/watch?v=AIIg2opcab0

Download the sample files there if you're curious what I mean.

Another issue is that when you have diffusion behind the lens, the size of the rear element is usually pretty consistent so you can keep the same strength approximately. But in front of the lens you might want a stronger filter for wider lenses to get the same amount of diffusion or halation or smoothness as a weaker strength provides on longer lenses. 

I like the look of Classic Soft and black nets and you can sort of use them as a shortcut to get a good look. But they look like you're using diffusion. I think Soderbergh and Spielberg and Richardson use them as it allows them to light a bit more sloppily and impressionistically than say, Deakins might.

But if you can light for it, you can get a good look with anything. Anyway if I were shooting with a P4K or C100 or something I would probably use vintage lenses and Classic Soft, but I would shoot Classic Soft on film or Alexa, too, because I like it. Absent Classic Soft, if I were just going for a smoother look, I think Digital Diffusion FX and vintage lenses would do it. Not sure what strength. Almost all my lenses are single coated or have primitive multi-coatings. (On digital because I like it, on film, because I can't afford Ultra 16s. I do have one modern Canon zoom, but even it is a bit washed out at the long end I believe.)

Edit: even if you don't want to use the Scatter software, look at the chart of familiar filters. Very useful to get an idea of what each does.

Thanks, this is all very useful.

I was thinking that I would want something that is a combination of contrast and resolution reduction without halation, but I'm not so sure now.  
Perhaps my main challenge is that it would be for shooting in available lighting, and so that means that the sun and other bright sources may well either be in frame, or out of frame but still hitting the filter.  Something like a contrast filter, with its very wide spread of light, would have a radical effect if the sun was hitting the filter, even if it was out of frame by a large amount.  I suspect these filters, and the people that want to emulate them in software, all assume that every scene will be controlled lighting and there will be no significant light sources in or outside of frame.
That's where the halation filters come in.  They spread the light quite widely, but no-where near as widely as the contrast ones do, so the frame won't be blown out when the sun is a long way out of frame.

I'll have to do more research and work out what that special something is that I'm seeing.  Interestingly, when I look at some of the filters I get that "ooh, it doesn't look like video any more" effect, but it doesn't seem to get less like video when the strength of the filter increases, so in that sense, maybe what I want is the filter that will do this "not video" effect but with the least amount of effect, so when I'm shooting something in golden hour the sun then it won't just blow out the whole frame, and I don't have to muck around with lens hoods.

Your comments about the filter being in-front vs behind the lens are interesting too, considering that I may use this on a zoom lens, so obviously that would change the strength of the effect, or perhaps more accurately, the size / radius of the effect in relation to the size of the frame.

Ultimately, all the ones we're talking about (digital diffusion, HDTV, smoque) all had that magic while not really impacting the image too much otherwise, except that I'm having trouble finding samples shot outside where the flare from the sun is a factor.  
I'll have to look into them more and see if I can extrapolate what they might look like from what I can find at sunset and the relative strength and spread from that Scatter plugin.

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I've watched a bunch of tests, and decided that what I want is something that spreads the light the furthest.  To put it another way, I want the edges of the frame to be lifted, and the area near the light-source to not be lifted much more than the edges.

This is a useful video for seeing the BPM filters in a range of situations:

For me, the BPM 1/8 filter was too much near the highlights, and too little on the edges of frame.

So, we can look at that Scatter plugin, and have a look at what it thinks the filters are doing..  for example:

image.thumb.png.f778fd8253bca27954902c54c1f1c753.png

That kind of view can show us the "response" of each filter type.

Here's the rest of them in each strength:

image.png.415bc505ae42b2a03819ebd527bcee1a.png

image.thumb.png.b270e0caa43d0e903f68f1c6d11f3f5a.png

image.thumb.png.bb71d65da09e0a4e2cd7fc79cb953b78.png

image.png.97f3fe73cde1720cb5befec692d9cca7.png

Very useful.  Using a Power Window, we can isolate the ones that look interesting:

This is the LoCon set:

image.png.1097a8b3c685fe49b6114c9f55d9b458.png

The 1/8 appears to scatter as far as the stronger ones, but obviously with less intensity.

This is the Glimmer Glass set:

image.png.71aefce48ebf969680862190e6b2dcf5.png

Also quite wide-spreading, but the diffusion is gathered nearer to the highlight, and drops off a bit faster.

Radiant Soft set:

image.png.85415a5d7a1feac21832b1bfc8720af5.png

Also wide spreading, but slightly less than the LoCon.

and Smoque:

image.png.68b12688af09c1e9da30cf5720f3ffab.png

and for reference, here's Black Pro Mist 1/8 - 1:

image.png.bbba884e528640f01203f7e1e86a549b.png

 

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On 2/22/2021 at 9:53 AM, HockeyFan12 said:

Contrast filters lift the black levels across the frame, resolution filters have a small-radius bloom or simply reduce the sharpness of the image without reducing the contrast, halation is a wider-radius bloom that reduces contrast locally but doesn't necessarily wash out the entire frame. Reference the chart on the Scatter webpage. I imagine Ultra Contrast would look like somewhat like a light gray solid if it were on that chart.

Yes, it seems they're all just combinations of small diffusion for skin softening, large diffusion for contrast reduction, and medium diffusion for when someone in a 90s TV show dies and goes to heaven.  

Just kidding!  The medium size is for 80s wedding photography.

6 hours ago, HockeyFan12 said:

Of those, Digital Diffusion FX is what I would recommend. Some of the black diffusion filters are nice, too, they lower the contrast less than the regular variants. 

From their proximity on the Tiffen triangle chart, Digital Diffusion FX and HDTV FX should be similar, but I vaguely remember a comparison that showed a pretty significant contrast reduction from the HDTV that the DD didn't have.  It's a pity it's not compared in the Scatter plugin website.

I'll have to look around and see what I can find in terms of comparison images.  I'm not afraid of lowering contrast too much as I'll be shooting in 10-bit and can expand contrast back in post.

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Yeah that sounds about right. 

Find a cheap Ultra Contrast filter on eBay or Amazon and try it out. 

I directly compared a Digital Diffusion FX 1 and HDTVFX 1 a while back. They looked similarly, the difference was HDTV FX had milky shadows. I have the files somewhere but I didn't label them so I doubt I can find them quickly. Years ago I tried out a bunch of Ultra Contrast filters alone and it wasn't what I wanted.

I was watching an explanation of MTF on YouTube and the idea is at different frequencies of resolution you get different amounts of contrast. You could probably model diffusion filters as MTF functions. 

You can definitely mix and match to get an interesting look. Spielberg's DP used a lot of diffusion filters but he also used bleach bypass and ENR processes that increased contrast so it was a balancing act between adding and subtracting contrast and getting the right ISO and contrast ratio. He typically used modern lenses, though.

Also the MTF function of film stocks rises above 100% and then dips down slowly. Digital stays around 100% until extinction. Normally digital sharpening looks bad to me, but I think the Alexa has a strong diffusion filter that slowly smooths out fine detail but Alexa ProRes has built-in sharpening that actually looks good because it's a wider radius of sharpening. Like unsharp mask with a radius of 2-3 pixels instead of 1, for instance, but I'm just guessing. There are little sharpening halos in 2k Alexa footage.

I sort of lost interest when it got so complicated. But I own vintage lenses and a few Classic Soft filters and I did like the look of Digital Diffusion FX but it was a very subtle difference.

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On 2/21/2021 at 3:51 AM, androidlad said:

Other than polarisation filter, all filter effects can be precisely emulated digitally in post. This allows for much greater and finessed control and guarantees glare-free.

Certainly there are many diffusion effects that can be emulated accurately in post.  Furthermore, there are also diffusion effects that are exclusive to post which can't be done with optical filters.

 

However, there are some optical filters which can't be duplicated digitally, such as IR cut/pass filters, UV/ haze filters, split-diopters, pre-flashing filters, etc.

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3 hours ago, tupp said:

Certainly there are many diffusion effects that can be emulated accurately in post.  Furthermore, there are also diffusion effects that are exclusive to post which can't be done with optical filters.

 

However, there are some optical filters which can't be duplicated digitally, such as IR cut/pass filters, UV/ haze filters, split-diopters, pre-flashing filters, etc.

Or accurate diffusion of any source that is clipped, or diffusion of any source that is out of frame...  but he'd know that if he read the thread I linked to.

I guess when I said "more info than you ever wanted" I was being prescient - he really didn't want the info in the thread!

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3 hours ago, kye said:

Or accurate diffusion of any source that is clipped, or diffusion of any source that is out of frame...

Yes, of course, but if one exposes properly and/or uses HDR features, then it might be possible to match "blown-out" areas in the frame.

 

Additionally, lens diffusion scattering from "out-of-frame" sources is also influenced by lens hoods and matte boxes.

 

In the 1970's, David Hamilton was the king of using lens diffusion while blowing-out highlights and light sources.  As I recall, black-dot lens diffusion didn't appear until the early 1980's, and Hamilton would push Ektachrome which increased contrast, countering the softness/flatness produced by the lens diffusion.  In addition, pushing gave coarser grain, which worked well for Hamilton's soft aesthetic.

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51 minutes ago, mkabi said:

Have you tried the 6K Anamorphic (open gate) with (Cheap) Anamorphic lenses?

See if that helps you on your quest of moving from the video look to the cinematic look. 

Agreed.  A good lens choice should reduce the video look more readily than diffusion filters.

 

Vintage lenses are ideal.  If you can't get Xtal Express, use a vintage spherical lens.

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On 2/23/2021 at 7:03 PM, kye said:

From their proximity on the Tiffen triangle chart, Digital Diffusion FX and HDTV FX should be similar, but I vaguely remember a comparison that showed a pretty significant contrast reduction from the HDTV that the DD didn't have.  It's a pity it's not compared in the Scatter plugin website.

I think this is my biggest gripe with these types of charts: They actually end up putting opposites together in some cases. Eg, if one filter is an equal balance between high contrast and high resolution, and another is an equal balance between low contrast and low resolution, then they would both be mapped in exactly the same spot (ie halfway between the contrast and resolution corners) even though they do the exact opposite of each other.

This is why I always find these charts so confusing! But hey, they look pretty!

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3 hours ago, barefoot_dp said:

I think this is my biggest gripe with these types of charts: They actually end up putting opposites together in some cases. Eg, if one filter is an equal balance between high contrast and high resolution, and another is an equal balance between low contrast and low resolution, then they would both be mapped in exactly the same spot (ie halfway between the contrast and resolution corners) even though they do the exact opposite of each other.

This is why I always find these charts so confusing! But hey, they look pretty!

The chart isn't great imo, but in general "contrast" means "low contrast." So anything in that corner is reducing contrast. Nothing is adding more contrast, everything reduces it somewhat. But filters with black dots reduce it less, Ultra Contrast introduces a controlled flare and reduces it more.

I do think the difference between Digital Diffusion FX and HDTV FX is stronger than the chart would indicate, but it probably depends on the strength of the filer. 

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  • 2 weeks later...

Just ordered a 1/8 Black Pro Mist filter.

I searched and couldn't find Low Contrast ones for sale in the size I needed anywhere on earth.  So I reevaluated, and looked at some tests I've been doing that have the sun directly in shot with various lenses, including vintage ones, and got a sense of the amount of halation that the vintage lenses gave.

These two videos are interesting and useful:

In the second one, the guy mentioned how he's a pro cinematographer and has the BPM 1/8 on his lens almost all the time.

I'll see how it goes.

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1 hour ago, kye said:

I searched and couldn't find Low Contrast ones for sale in the size I needed anywhere on earth.

What size do you need?  Here is an 82mm Tiffen Low Contrast filter for sale.  If your lens is smaller, you could just use a step-up ring.

 

By the way, there are plenty of YouTube videos on making DIY black-promist filters.  One can even make a smaller increment than 1/8.  To approximate the the black dot process one needs to apply the black spray paint before the hair spray (or other diffusion spray).

 

Also, the Harrison & Harrison black dot originals can still be found for sale in sets or individually.

 

 

2 hours ago, kye said:

These two videos are interesting and useful:

It's always puts a smile on one's face when a YouTuber conducts a test with just a frontal light source, and the subject turns their head from left to right.

 

 

2 hours ago, kye said:

In the second one, the guy mentioned how he's a pro cinematographer and has the BPM 1/8 on his lens almost all the time.

As he suggests, it's generally best to use a lenser (flag the light source outside of the frame from hitting the lens/filter) or a hood/matte box.  One can always add ambient fog in post.

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4 minutes ago, tupp said:

What size do you need?  Here is an 82mm Tiffen Low Contrast filter for sale.  If your lens is smaller, you could just use a step-up ring.

By the way, there are plenty of YouTube videos on making DIY black-promist filters.  One can even make a smaller increment than 1/8.  To approximate the the black dot process one needs to apply the black spray paint before the hair spray (or other diffusion spray).

Also, the Harrison & Harrison black dot originals can still be found for sale in sets or individually.

Size matters in my setup, but I got the 58mm BPM 1/8 so that's fine.  Those Harrison and Harrison filters are fascinating - a couple even look like they have bubbles in the glass.  I'm not familiar with them, but for $500 US I can buy half a P2K, so that's where my money would be better going!

In terms of having a set of filters, I know it's typical to add more diffusion on longer focal lengths, but I looked at the tests and found that the black levels typically get lifted almost the same amount from a 1/8 and then I can add extra diffusion to longer shots in post if I want to, with the 1/8 taking care of the things you can't do in post.

I've seen DIY videos of people making their own with UV filters and black spray paint, but the 1/8 is ok.  My concern with the BPM was that it would be too strong near the hot spot and too weak further away, and I'm sure that I can make a diffusion filter, but I'm definitely not going to be able to control the distribution of that diffusion across the frame.

4 minutes ago, tupp said:

It's always puts a smile on one's face when a YouTuber conducts a test with just a frontal light source, and the subject turns their head from left to right.

Why?

4 minutes ago, tupp said:

As he suggests, it's generally best to use a lenser (flag the light source outside of the frame from hitting the lens/filter) or a hood/matte box.  One can always add ambient fog in post.

I frequently follow a subject and am panning and pan from almost flat-light to back-light and the sun in frame.  

It's all well and good if you're shooting something where you get 20 minutes to set up for 5s of footage, but some of us struggle to get 5s to setup before a 2 minute shot.  Sometimes I feel like the pros would recommend a C500, wide cine prime and Ninja recorder to a skydiver who wants to shoot POV video mounted to their helmet on the way down!

4 minutes ago, tupp said:

One can always add ambient fog in post.

True, but lifting the blacks in post also lifts the noise, which is great if you're trying to create an alien fog full of angry nano-bots who randomly self assemble in squares, but it's not an aesthetic I'm really looking for.

Doing it physically raises the black levels optically, which then enables you to lower the exposure to put them back to black and get more highlights, increasing the DR, or for you to have higher black levels in the file, which gives you a softer look without having visible noise.

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42 minutes ago, kye said:

Those Harrison and Harrison filters are fascinating - a couple even look like they have bubbles in the glass.  I'm not familiar with them,

Although the company is gone, Harrison & Harrison was a dominant filter maker for cinema "back in the day."  They invented black dot diffusion, which is the basis of Black Pro Mist filters and of other derivative filter technology.

 

47 minutes ago, kye said:

but for $500 US I can buy half a P2K, so that's where my money would be better going!

Well, the set of 5 filters that I linked was listed at US$200, but, as mentioned, H&H filters can can sometimes be found individually.

 

What is a P2K?  Definitely interested in that.

 

56 minutes ago, kye said:

I looked at the tests and found that the black levels typically get lifted almost the same amount from a 1/8

Keep in mind that although the black levels can be lifted with diffusion filters, that doesn't mean that one will see more detail in the shadows.

 

1 hour ago, kye said:

I've seen DIY videos of people making their own with UV filters and black spray paint,

To approximate black dot effect, the black spray paint specs should be "embedded" within a diffusion layer (hair spray or something similar).

 

1 hour ago, kye said:

My concern with the BPM was that it would be too strong near the hot spot and too weak further away,

Not sure what you seek here nor if any existing lens filters can yield such results.

 

1 hour ago, kye said:

I'm sure that I can make a diffusion filter, but I'm definitely not going to be able to control the distribution of that diffusion across the frame.

On the contrary, if you DIY, you are in complete control of the distribution of the diffusion medium.  In the videos that I watched, it didn't seem too difficult.

 

1 hour ago, tupp said:

It's always puts a smile on one's face when a YouTuber conducts a test with just a frontal light source, and the subject turns their head from left to right.

1 hour ago, kye said:

Why?

I don't know, guess it's just me...

 

1 hour ago, kye said:

I frequently follow a subject and am panning and pan from almost flat-light to back-light and the sun in frame.

If you have a good lens hood or matte box (or a solid French flag), the flare will be reduced when the Sun is out of frame.

 

1 hour ago, kye said:

t's all well and good if you're shooting something where you get 20 minutes to set up for 5s of footage, but some of us struggle to get 5s to setup before a 2 minute shot.  Sometimes I feel like the pros would recommend a C500, wide cine prime and Ninja recorder to a skydiver who wants to shoot POV video mounted to their helmet on the way down!

It shouldn't take 20 minutes to "set-up" a lens hood.

 

1 hour ago, tupp said:

One can always add ambient fog in post.

1 hour ago, kye said:

True, but lifting the blacks in post also lifts the noise, which is great if you're trying to create an alien fog full of angry nano-bots who randomly self assemble in squares, but it's not an aesthetic I'm really looking for.

I am not suggesting lifting the blacks.  To add ambient fog in post, one basically slaps a smooth white, slightly diffusing layer/track over the image, and then adjusts the opacity of that white layer/track as desired.  Doing so is very similar to an out-of-frame light source hitting a lens diffusion filter.

 

1 hour ago, kye said:

Doing it physically raises the black levels optically, which then enables you to lower the exposure to put them back to black and get more highlights, increasing the DR, or for you to have higher black levels in the file, which gives you a softer look without having visible noise.

If one wants the look of ambient flare on a len diffusion filter, one can similarly lower the camera exposure and then use the post method stated directly above.  The results will closely simulate doing it all in-camera with the higher black levels and no extra noise, plus one will have more control over the level of "ambient flare."

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I've never used a diffusion filter before, but based on the 2 lenses that are going to be my principle workhorses, the Sigma's 28-70mm f2.8 and 65mm f2, the latter being very sharp, I've ordered a Freewell 1/8th Glowmist.

Some absolutely stunning footage shot with the 65mm f2 and the variable ND version (which is supposed to be somewhere between 1/8th and 1/4) by self-proclaimed douche-bag YouTuber Vu of nVu Films and the closest I have come across recently to my ideal 'look'.

OK, it was shot on Sony (spits on the floor) but my humble S5 will need to do instead.

I'm going to try it first on the 28-70 arriving this week and if it works like I expect it to, will get another for the 65 when I buy that at some point in the future.

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I found an interesting use for a polarizer filter recently which I hadn't thought of before.

I use my GH5 as a webcam for teams calls with a soft keylight. One issue is that my 27" monitor adds a lot of additional light that depends on what's currently on my screen. This will often add a blue tint to my face if I'm looking at a document, or no tint if it's a darker screen. Adding a polarizer filter to my GH5, I am able to remove most of the reflections from my monitor without affecting the keylight. I did not expect it to work so well, and the real reason I added it was because I needed some ND. 

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