Last time I checked there is no big 'sharpness‘ knob on a camera.

Sticking diffusion in front of the lens or softening in post is not a universal solution.

Your problems start with the lenses and what MTF frequencies they are tuned for, in what frequencies they emphasize contrast and how those factors will interact with the resolution of a given sensor.

Modern glass coupled with a very high resolution sensor is difficult to diffuse. By the time you stack enough diffusion on your lens to knock down unwanted detail you will very likely introduce blooming in glows. Especially if there are bright point lights in the scene or if you are shooting in to the light. Your diffusion is also having a global effect on the image (i.e. all frequencies), which is something you may want to avoid for various reasons. Also keep in mind that every diffusion filter you slide in your matte box is another potential source of reflections.

You can avoid some of these problems by shooting with vintage glass on a high resolution sensor, which is why the price on older cine glass has exploded over the past few years. But this too will only help you so much.

Aside from the technical issues, are you really going to have the time to dial in that much diffusion for every setup? In production, time is money and I’m not even going to get in things like the politics of the impatient actor / director, light changing on location etc

If you’re softening in post you would need a filter that reduces detail based on Fourier transformation, which the vast majority of software does not utilize. Applying a blur is not going to cut it, since you need to remove detail in certain frequencies and preserve it it others. Blurring the image globally is not going to solve your problem. It's just going to make it look soft and out of focus.

Throwing a little grain on the plate with some magical After Effects plugin isn't going to cut it either and just for the record, adding grain can actually enhance perceived sharpness, since it adds a certain level of acutance and gives your eye something to lock on to.

Diffusion in post is no magic bullet and you run the risk of your image looking unnaturally processed.

And of course, what is the point of capturing giant 6k images that take up massive amounts of storage and require huge amounts of processing power, if ultimately you’re going to reduce the detail in them to the point where you may as well have shot with la ower resolution camera in the first place?

But as an accomplished Photographer / Cinematographer / Editor you already knew all of this.

I hope they make a version of these lenses with a functional aperture at a higher price point.

65mm film looks very different than 6k digital capture. Also keep in mind that the 1960's 65mm film stock that Lawrence of Arabia was shot on had much larger grain than what you get today. I've seen the restored Lawrence at the Cinerama Dome and while it was stunning, it was not offensively sharp and the grain was noticeable (in a pleasant way).

But 6k digital from an F65 or the Alexa 65 with modern glass is going to be vastly sharper and will look very, very different than film 65mm.

D16. I have one and the color out of the Kodak/Truesense CCD is stunning. Just make sure you properly import the footage in to Davinci 11 to avoid the magenta color cast you see in a lot of clips.

I second that.

No one in VFX wants to do an entire movie in 4k. Yes, there are some shots with very fine detail that are sometimes done at 4k to avoid aliasing, but other then that it's 2k all the way.

4k Render times would go through the roof, the networks and workstations couldn't handle it and you would end up having to soften the 4k renders in the comp to match the 4k live action footage anyways.

There certainly is a place for the Alexa 65 in VFX for specialized or very specific fx, but in general we use the same A camera as production.

The Epic is not a favorite for vfx, because of the compression, noise and odd color science. There is other odd behavior with shooting green screens or stacking a lot of ND in front of the RED, that doesn't make it ideal for fx. ArriRAW or Sony RAW are much preferred, especially for green screen work.

There is plenty of resolution in the Alexa or Sony footage, unless you are doing something very specific that requires an exceptional amount of definition. In that case the Alexa 65 or F65 would be ideal.

Some people like Fincher 4k window the full res Epic plate, so they have room for stabilizastion and cropping.

But in general everything from the Alexa, Sony or Red gets scaled down to 2k for FX work. Some shots are done at 4k for technical reason. $k for FX is coming, but it will be a few more years, before it replaces 2k.

As far as sharpness is concerned we always match what the DoP did for the production. And in that case excessive sharpness from downscaling is not necessarily desirable. Most DoP spend a lot time reducing the sharpness of modern cameras and lenses with diffusion and vintage glass on set and maybe in the DI. Even the sub 4k Alexa may get diffused and the subject lit with soft light. It has to be kept in mind that the stars are the 800 lbs gorilla on set and if they don't feel that they are being shown in their best light (no pun intended) they will pull rank and you are going to lose.