no many recent films are upscaled to IMAX.. they have a new technique for that.. a few films like the Dark Knight Rises are actually also shot with IMAX Cameras..

Well depending on the aspect ratio it determines the horizontal resolution: let's take widescreen as an example
on a newer 35mm with 4000 lines the aspect ratio and soundtrack will give you a screen resolution of ~3100 lines so 3k..
the newer 35mm with finer grain (better detail, more lines) are from the 1980.
So a pre 1980 film with around 3000 lines using the widescreen aspect ration would be around ~2400 lines.. so closer to 2k..

a 4K scan can capture more stuff then a 2K scan, but it isn't really necessary cause as you can see there isn't actually that more information on the original film.. the danger here is that the movie gets upscaled to 4K it can give you actually a worse image quality then 2K..
Last month we had HD commercial, 1080p, upscaled to 4K for use in cinema... which didn't go to wel cause the colors and image blurred out...
So with a 35mm the same will happen but less drastic then my HD commercial.. upscaling film is never a good thing..

As for films degrading over time, how easy is it to restore them? well you can't restore them when you scan them... now the trick is to find the best copy out there with the least wear, scratches, dust, light exposure, etc..  all of that effect the quality.. you can only clean the 35mm but not repair scratches, burn marks, light exposure..  most of the time the 1st master film will have wear and tear because of the process making copies of it.. that's why some movies take a long time to have a blu ray version.. finding source material they can scan in can be difficult.. the older the movie, how harder it gets.. after they film is scanned they can make digitally repairs.. but not everything..

I do think 4K is the future, with 4K videocamera's but it will take time...

Would it not be beneficial to color resolution though? All digital videos go through 4:2:0 chroma subsampling before compression begins.
Effectively leaving you with 960x540 for color resolution. (That's why upscaling causes color bleeding) I suppose this is not going to change for 4K blu-rays, but those will have 1920x1080 color info when captured from the original.

Is 35mm film good enough to capture full 2K digital color at least?
It should be for Disney movies at least, I read somewhere that they store their movies with the color info split out into separate black and white reels for better conservation. Then they are combined again to make a full color version.

So it's only 4k if it uses an aspect ratio close to 4:3 that covers the whole film? And the film won't have a horizontal resolution equivelant to around 3840? The resolution is still much higher than 1080p and closer to 4k and I've heard that it can vary throughout a film, so wouldn't it still benefit from being remastered at that resolution? I've also heard that any IMAX film will have more quality than 4k.

no many recent films are upscaled to IMAX.. they have a new technique for that.. a few films like the Dark Knight Rises are actually also shot with IMAX Cameras..

Well depending on the aspect ratio it determines the horizontal resolution: let's take widescreen as an example
on a newer 35mm with 4000 lines the aspect ratio and soundtrack will give you a screen resolution of ~3100 lines so 3k..
the newer 35mm with finer grain (better detail, more lines) are from the 1980.
So a pre 1980 film with around 3000 lines using the widescreen aspect ration would be around ~2400 lines.. so closer to 2k..

a 4K scan can capture more stuff then a 2K scan, but it isn't really necessary cause as you can see there isn't actually that more information on the original film.. the danger here is that the movie gets upscaled to 4K it can give you actually a worse image quality then 2K..
Last month we had HD commercial, 1080p, upscaled to 4K for use in cinema... which didn't go to wel cause the colors and image blurred out...
So with a 35mm the same will happen but less drastic then my HD commercial.. upscaling film is never a good thing..

As for films degrading over time, how easy is it to restore them? well you can't restore them when you scan them... now the trick is to find the best copy out there with the least wear, scratches, dust, light exposure, etc..  all of that effect the quality.. you can only clean the 35mm but not repair scratches, burn marks, light exposure..  most of the time the 1st master film will have wear and tear because of the process making copies of it.. that's why some movies take a long time to have a blu ray version.. finding source material they can scan in can be difficult.. the older the movie, how harder it gets.. after they film is scanned they can make digitally repairs.. but not everything..

I do think 4K is the future, with 4K videocamera's but it will take time...

The theoretical maximum for fine-grained 35mm film is about 8700*5800 pixels or about 50 Megapixels. So regardless of aspect ratio, any 35nm film could be scanned to better than 4k resolution (whether you want/can do that or not depends on your budget and film quality).

They're upscaled to IMAX? How exactly does that work and how is it an advantage over traditional film? I also thought that it was only the vertical resolution that was affected by aspect ratio. Does upscaling affect film more than digital video? Because upscaling doesn't usually affect image quality.

Do you think digital videocameras will replace film? Is there any reason why it hasn't yet?