Best In-Camera 4k scaled down to 1080

[maxotics]

This is a question I think may deserve its own thread.  Understand if you move it Andrew.  How is the in-camera a7 in-camera 1080 compare to post-processed 4k to 1080?  Same for Panny GH4 and LX100, etc.  Is a7 with externally recorded 4k end up as better 1080 than the camera, or is internal GH4 4k scaled down to 1080 end up as better 1080 than the a7 internal?  Can you end up with better graded footage from a GH4 4K than a7 source 1080...etc.

 

How important will an external 4k recorder be for the a7s?

[fuzzynormal]

Downscaling just always looks better.  Heck, I'm of the age that I first realized this with VHS tapes.  My home movie camera and the latest rental from Blockbuster both delivered, realistically, about 300 lines of horizontal resolution, but man...those film transfers just looked so much more cleaner.

 

Still, your desire to know more of the "why" of it all --with comparisons seems like a worthwhile inquiry.

 

In the meantime I operate under the naive wisdom of my 1980's be-kind-rewind experiences:  more rez scaled into lower rez just looks good.

[Guest Ebrahim Saadawi]

Recording full 4K pixel by pixel then scaling down in PC-like quality in-camera isn't an easy task, only the C100/300 do it as far as I know, the other gh4, A7s, NX1 record 1080p in a different way than the 4K mode.

Why would that be of any improtance though? I mean converting to 1080p is such an easy step to do in post and gives you the advantage of re-framing that the C100 don't. I would rather have my 4K masters and convert later to 1080p rather than have already converted 1080p, even if the result is the exact same quality, agaun because of the reframing/crop/post-motion potential.

[maxotics]

Why would that be of any improtance though?

 

  My question is more about how important external recorders are if, in the end, you're going to end up with 1080 (assuming no cropping in post).  So do you really need an external recorder for the a7s if you're going to use 1080 footage?  Or, is the 1080 from the lx100 as good as its 4k post down-sampled?  I understand the you always want the highest-data footage.  Maybe this is a bad question ;)

[hmcindie]

Depends on your level of quality need.

 

If I would be a high budget director/dop I would never use the A7s with internal footage. It would have to be with an outside recorder, just to get rid of the compression.

 

If I'm a low-budget music video director, I wouldn't give a damn and just shoot with it.

 

C100/C300 are the only cams that make really detailed 1080p at the moment (And C100 has the horrible AVCHD), A7s/GH4 are quite close but can't match it completely. So if you want better you need to shoot 4k and scale it down.

[Guest Ebrahim Saadawi]

To answer the question Maxotics yes none of these cameras produce a 1080p internal image that's identical to their 4 scaled-down ones. So shooting 4K either internally or externally is the way to get the highest image quality.

But for what it's worth I think the A7s specifically does the best job in producing a 1080p internal image, but the 4K scaled down will also be better. The C100/300 do scale the 4K image internally and gives the same advantage as scaling down in post (In resolution. Recording 4K on the C500 gives still gives an advantage in colour as it's 12bit vs 8bit) it's the only one I can think of.

I'd rather have a 4K image and scale down in post. Such a miniscule inconvenience that gives cropping/reframing options and also gives the option of outputting a much higher resolution 4K image. I do get not wanting to bother with either though and wanting to get perfect 1080p internally, especially in news/broadcast/documentary shooting and anything that doesn't go through intensive post production and tweaking.