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What Is A Cine Lens And What Makes It Budget?

In this age of perfection and the illogical push to reduce it, what makes a cinema lens and why are some considered budget, when others are the price of a house?

I have gone into the basics of cinema lenses in previous posts, such as mechanical structure and consistency across the range, so this is more about the why of the huge disparity in lenses.

I have watched a few comparison videos lately and my main take away has been, even the experts cannot tell from raw images alone unless (1) they are overly familiar with the look of one lens over the others or (2), depth of field or other factors give them away. https://www.youtube.com/watch?v=0TSkj1AK8qs

Another good video on a lens set comparison, and much dearer ones than the Hope lenses is this, especially the colour matching etc.

https://www.youtube.com/watch?v=blkaxl78FGk

Sharpness.

It is accepted that moving pictures are not as needy as still pictures when it comes to sharpness. The movement to add mist or glow filters to even the dearest lenses is proof that as things get sharper and more detailed, we crave the more realistic reality that we personally do look at things that critically unless we are forced to.

Our eyes are amazing (truly), but even perfect vision does not match in reality what we can be delivered on a huge, high reslution screen and when we do, to what end? I can be blown away by a scene with every pore sharply rendered, but I d not need to see that and when I do, does it distract from the story itself?

Sharpness and a very good filter do add something, the ability to perceive high sharpness under a veil of smooth unsoftness is like the effect of a sharper image in news print. You could tell, even if mathematically the print is the limit. A less sharp lens and/or poor filter do not look the same, but they look a way of their own that is also acceptable, which is why many old lenses are being used in modern productions, be they re-house Russian stills lenses, or ancient cine glass. Is it just a very expensive exercise of two steps forward and one back?

A tight crop from a IRIX 150mm cine-macro image. Too sharp, too contrasty?

The reality is sharpness in moving stock only needs to be non-distracting as the fact it is moving at 24 fps will rob you of the ability to see high detail anyway. Freeze the frame and you can see it, revealing that too much and too little can both be bad. A decent budget lens can be sharp, a stills lens, even a kit one can be sharper. The key seems to be “perfect” sharpness balanced with other factors.

Contrast.

Sharpness and contrast often get lumped together as a more-is-more-is-good thing. Contrast, even more than sharpness needs to be cinematic, which is to say, controlled. Moving stock often lacks the dynamic range of a stills image or if not, it lacks the controls and in the field control. The camera will determine the theoretical dynamic range, but the lens can also help determine the contrast coming down the lens.

Another reason mist filters are used is to add a stop or two of DR, by blooming highlights and lifting shadows. This both reduces contrast and makes the retrieved information nicer to look at.

Cinema lens “magic” is often found in contrast. Smooth highlights, open shadows, “softer” colours are all cinematic signatures and make the crafting and watching of the medium easier.

Can a budget cinema lens offer contrast that makes a difference to just using a stills lens?

Ironically, lower contrast is easy to achieve. Whether it is special or not comes down to a lot of other factors, but theoretically, there may be a cheap lesna out there t match the look of a much dearer one.

The mid tones are where cine lenses need to do most of their work as highlights are often controlled or avoided, shadows lifted or crushed. If the story cannot be told in the mid tones, it is lost. Maybe this is why older glass cuts it. Older lenses needed to get as much as they could out of the fairly rigid film media.

Colour.

This is not really down to the lens as much as many other factors, the camera most importantly, but the lens can contribute a temperature, contrast (see above) and flare control (see below). Probably more important here, budget lenses do fall short with lens to lens consistency, but sometimes dearer glass is less than perfect also.

The colour of this file is to my eye clearly less punchy than many of my stills lenses, which for video is ideal.

In the making if “The Creator”, famous for using consumer grade cameras, the lens, a rehoused antique Kowa 75 Prominar anamorphic was used the bulk of the time. This is a professional lens but nt a cutting edge design. They use multiples of the same lens, to match perfectly, an easy fix and in these days of multi format mounts and cameras and high resolution, it is even possible to get different focal lengths out of on lens.

I bought two Spectrum lenses (35 and 50), that do not match in colour. I could have in hind sight bought the same lens twice (the warmer 35), used one as a 35 and the other as a crop frame 50.

Distortion and vignetting.

This is an odd one. Cine lenses are as often as not chosen for their distortion characteristics, especially anamorphic lenses. Just look at Shogun (shot with Hawk and Vantage anamorphic) or any Wes Anderson films to find odd, even broken edges and corners of the frame and bent horizon lines.

Vignetting, like flare and distortion is often used for it’s negative effects as much as avoided.

That old TTArt 35 again, with all it’s faux cine lens goodness.

Are budget lenses too well corrected? Are they lacking a distinctive feature?

Flare.

Like distortion, flare can be a more is more, less is more or different is more thing. Generally there is a limit to how much can be accepted, but the shape, colour and proliferation of flare is an art form in and of itself. In the making of “Saving Private Ryan” for example, uncoated lenses were used to mimic the older glass used at the time, exaggerate flare, reduce colour and contrast.

Even when I tried to break my budget 12mm, it managed to produce this.

Most stills lenses treat flare as the enemy, making us look to older glass or software to get that “vintage” look. Cine lenses are more of a balancing act of some effects to taste, hopefully without loss of contrast and control.

Again, many cheaper cine lenses actually have their own flare signature and more recently they are reliably controlled. Better or worse? Up to the viewer I guess.

Rendering.

A bit of all of the above, rendering is a subjective and often ambiguous thing. Bokeh, colour, contrast, “draw”, distortion, sharpness all contribute along with other factors. This is probably the base line of what makes a better lens better, something that is hard to put into words, but easy to put a price tag on.

This scene, regularly shot be me, is rendered gently by the Vision 12mm. The Bokeh is pleasant, contrast strong enough without looking like a stills image and the shadows are open, the sharpness is more than enough for moving stock, distortions are visible, but in video, so what?

In testing I have seen a clear difference between my stills lenses and my budget cine glass in rendering. The cine glass is usually gentler, smoother and more controlled, less punchy and “hard” sharp. Is that difference enough of what we need?

The rendering of a $400au Hope 50mm. Ignoring all the other elements that can effect an image, is this decently rendered? What exactly does that mean and when does it mean more than the subject itself?

So, can a cheap cine lens be justifiably called cheap?

Cameras make more difference, true cinema cameras giving smoother footage and the application of a skilled and experienced crew cannot be under estimated (see the add for the iphone 15 making a movie).

Is the main thing against budget lenses, the fact that as budget lenses, they do nit get the best rides. Are they perfectly valid, just so cheap, they are not given the best treatment overall? Some (most) do not even come in the right mounts, like PL for the best cams, so I guess it’s impossible to test. Any car can drive at the speed limit, so if the speed limit of “cinematic” viewing is the viewer, what is the speed limit.

Could the most basic of budget lenses actually be technically better than many of the older lenses used in film making, which are in turn re-housed for modern works? Could “Ryan” have been filmed with cheap glass for much the same result?

A $75k Arri with a $400 lens? Seems crazy, but would anyone really notice? A consumer FX3 and an antique Kowa fooled many and I would argue that was the wrong way around.

From a technical perspective, many of the things that make a stills lens measurably cheap are irrelevant, even contradictory. AF is absent by design, visible flare and distortion are often sought out, reduced colour and contrast desirable or retro fitted. Even the mechanics are easy to do, with designs often clones of classics, consistency is desirable but there are work arounds.

So why is one lens, a mechanical monster with no electronics, probably a simple design, little thought put into weight or size limits or even materials and modern needs often reduced and then controlled by reduction devices like filters, a steep $15k or more, and another with very similar performance only $400?