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Lens aberrations to control fill?


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Hello everyone,

I recently listened to Suzie Lavelle’s interview regarding her work on “Normal People” and at one point she mentioned that she often relied on lens aberrations of Canon K35s lenses to give her the fill she needed. 
I was wondering if someone would elaborate on this practice a bit more and clearify what she meant by that?

I’m assuming the K35s either increase or reduce image contrast overall and one could use that inherent quality to get higher or lower fill levels right out of the gate?

Thank you!

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I was watching an interview with Timur Civan the other day, talking about the Classic version of Sigma's cinema primes. The classics have either no coatings, or reduced coatings, which provokes a lot of flare and veiling. Civan discussed the fact that the veiling was actually enough to materially affect exposure, reducing contrast and lightening the blacks.

The veiling is very intense on those uncoated lenses, more intense than a K35, which wasn't really intended to do that at all. I've not done anything serious on K35s but I have seen video that suggests they do veil and glow a bit wide open, as do many things. You could achieve much the same thing, and probably more consistently, using some sort of low-contrast filter (click here to see a demo of Tiffen Ultra-Contrast 3). There are also things like an Arri Vari-Con, Panavision Panaflasher or Camtec Color-Con, which are essentially very light diffusion filters that are illuminated from the edge with LEDs to illuminate the whole frame. All of these will add at least a small amount of glow to highlights, unavoidably.

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Camtec Color-Con 6x6 — Camtec

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I'm also guessing it's mostly a matter of older coatings. 

I think with older lenses you can get away with lighting a bit more carelessly or using less fill. On the other hand, if you over-light, they don't look so good imo. 

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Funny thing is that people talk about the low-contrast of uncoated lenses as allowing them to use less fill light, but they ignore that an uncoated lens loses light overall.  I did a pilot using a set of coated and uncoated Zeiss Master Primes and the uncoated version was maybe a 1/3-stop slower in terms of exposure.

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41 minutes ago, David Mullen ASC said:

Funny thing is that people talk about the low-contrast of uncoated lenses as allowing them to use less fill light, but they ignore that an uncoated lens loses light overall.  I did a pilot using a set of coated and uncoated Zeiss Master Primes and the uncoated version was maybe a 1/3-stop slower in terms of exposure.

Sigma Classics are at least that much slower than the conventional types. The conventional range is T1.5 between the 20 and 105, whereas the Classics are 2.5. The 14 and 135 are a little slower.

I never understood why wide lenses are slower.

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1 hour ago, David Mullen ASC said:

Funny thing is that people talk about the low-contrast of uncoated lenses as allowing them to use less fill light, but they ignore that an uncoated lens loses light overall.  I did a pilot using a set of coated and uncoated Zeiss Master Primes and the uncoated version was maybe a 1/3-stop slower in terms of exposure.

David, I’m assuming going into a shoot knowing this, you can increase your light levels to compensate for the loss in exposure and still get away with not needing/wanting to fill in the shadows as much?

It also reminds me of a photo of your dog you posted on your instagram quite a long time ago where you compared two different lenses and their rendition of saturation and contrast - I remember being so suprised by the difference in look. 

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17 minutes ago, Olivier Metzler said:

David, I’m assuming going into a shoot knowing this, you can increase your light levels to compensate for the loss in exposure and still get away with not needing/wanting to fill in the shadows as much?

Since I wasn't lighting to wide-open on the Master Primes, it was just a matter of opening up a little to compensate.

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14 minutes ago, David Mullen ASC said:

Since I wasn't lighting to wide-open on the Master Primes, it was just a matter of opening up a little to compensate.

I see. 
Now, would you say that shooting with uncoated lenses gives you more control over your shadows though? Considering that instead of having to build a big soft source to lift your shadows, with uncoated lenses you might “only” have to add negative fill to get them darker?

Controlling the toe of the exposure can be quite tricky - at least from some shoots I have participated in - and I feel like uncoated lenses could offer a solution to that? Though as you said, it doesn’t only affect just the shadows but the entire exposure.

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An uncoated lens cannot reveal any more details in the shadows. It only spreads some of the light from the highlights to the shadows. But it does that uniformly. So it transforms dark shadows with no details into lighter grey shadows with no details. Still no new information is introduced. I can't imagine an uncoated lens can be a substitute for fill light. 

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10 minutes ago, Raymond Zananiri said:

An uncoated lens cannot reveal any more details in the shadows. It only spreads some of the light from the highlights to the shadows. But it does that uniformly. So it transforms dark shadows with no details into lighter grey shadows with no details. Still no new information is introduced. I can't imagine an uncoated lens can be a substitute for fill light. 

Doesn’t the notion of “lighter grey shadows” inherently mean that there is more information though? Or is it an apparent increase in detail (even if there isn’t any from a technical standpoint)?

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It's a similar discussion as to whether flashing film increases shadow detail.

It's hard to say - anything that lifts the blacks by adding a veil of white will bring dark shadow detail up into a more visible realm, just like lifting the blacks on a TV monitor will -- the detail is already there, it just normally starts to fall into and below the designated "black" of the display gamma (whether on a monitor or film print stock), so if you can live with the blacks being not black, you will see more shadow detail.

In terms of actual new shadow detail being captured from flashing or low-con filters, uncoated lenses, etc. if there is any, it's a pretty small amount, perhaps not significant (like a 1/6th-stop of extra information) -- most of the perception of increased shadow detail comes from the lifting of the blacks.

A good test would be to shoot a chart with a pure black square in it, along with the subject, both normal and with whatever technique you are using to lower contrast (flashing, low-cons, old lenses, etc.) and then color-correct the fogged image until the square is black again and then see if there is still more shadow detail.

All this to say that such techniques made more sense with the gamma of the display technology was fixed, like with print stock -- but with digital color-correction where black level and low-level information can be adjusted, it's unclear if there is still an advantage to using optical techniques of contrast-lowering.

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23 hours ago, David Mullen ASC said:

All this to say that such techniques made more sense with the gamma of the display technology was fixed, like with print stock -- but with digital color-correction where black level and low-level information can be adjusted, it's unclear if there is still an advantage to using optical techniques of contrast-lowering.

So very true!! I spent hours testing different diffusion and fog filters and they all looked so different initially. But once I normalized all the images in post to the same black and white points, I was shocked how they ended up looking so similar at the end. The only difference that remained was with those filters that have high halation effects.  

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