Does film have an artifact equivalent CMOS smear?

[Marcus Friedlander]

Hey everyone,

Quick question.

I was watching a commercial that was shot on film, but at one part it looks like there is a CMOS smear-like artifact? Am I correct in seeing that or is that artifact something else? If so, does anyone know what it is?

The artifact is at 1:12 but this commercial is lovely and worth watching in its entirety.

https://mixinglight.com/portfolio/look-inspiration-warm-commercial-look/

thanks!

 

[Mike P.]

That's not CMOS smear, but anamorphic flare from the lens...

 

[Marcus Friedlander]

Thanks for the response. Do you know why it looks more like a grainy blotch instead of a clean blue line?

 

[Mike P.]

It looks pretty blue/purple on my monitor... You're talking about when she leans against the grandfather clock, right? (there's another example at 0:54-55 when she's with the plant).

It looks more blotchy because of the angle it's coming in lens at and the source (from the window)... Anamorphics are usually only streaky when you have a hard light pointed directly into the anamorphic lens (otherwise it's bouncing and reflecting off glass and barrel all over the place).

 

[Marcus Friedlander]

Hmm maybe it's just me then because the grandfather clock part is the correct part. Now that I think of it though, I did watch it on an iPad so maybe that caused some of the issue. When I get a chance I'll look at it on a proper screen and see if I can see the difference.

And thank you for that little anamorphic streaking lesson! I definitely did not know that! Always love learning new things, so much appreciated! Thanks!

 

[Dominik Muench]

To (potentially) answer your original question, I don't think film can have an artifact like that because unlike a sensor where the pixels are in fixed arranged positions, film emulsion and grain/ silver halide structure varies from frame to frame and I assume that would therefore chancel out such an effect.

 

[Douglas Underdahl]

Look up halation.

 

[Marc Wielage]

There is also the potential for strobing problems in film, which are a function of shutter angle, exposure, and some other factors. This can be an issue in horizontal pans done at certain speeds. This is the closest I can think of to CMOS rolling shutter problems.

 

[Marcus Friedlander]

To (potentially) answer your original question, I don't think film can have an artifact like that because unlike a sensor where the pixels are in fixed arranged positions, film emulsion and grain/ silver halide structure varies from frame to frame and I assume that would therefore chancel out such an effect.

Film still needs to be scanned though right? Which means at some point it's going through a digital sensor of some sort right? Could digital type artifacts be induced there (unrelated to this particular example. Just, in general?)

 

[David Mullen ASC]

In a film scan or video transfer, you sometimes can create aliasing artifacts and you sometimes get electronic noise in bright skies that are particularly dense on the negative, neither of which are in the original film. And of course, you can introduce sharpening artifacts.

 

[Anton Shavlik]

I think the CMOS smear happens when a pixel (photo site) gets hit with enough light that its electrons overflow and contaminate the voltage readout for all the nearby pixels in that row. Film doesn't really have an analogue to that.