Sony a7S vs. Canon C100

[Andrew Ray]

So I run a small film company, Lightworks Films, and we have done a few reviews on the Canon 5d Mark III and the C100 (here is one of my reviews). I am really interested in purchasing a Sony a7s, and to my eyes (online) the camera looks better than the C100 - can anyone with both cameras comment? Or anyone who has used both? I am specifically referring to resolution - not 4k, but how well the a7s resolves 1080 compared to the c100 at 1080. Thanks for your thoughts!

[Guest Ebrahim Saadawi]

-Not used A7s yet, However from the files I've been checking, it seems to be at least equally sharp and detailed as the C100 if not a little better
-Only reason to prefer C100 is specifically requiring the C100 ergonomics, other than that the A7s is a newer technology and probably a better camera overall now 

;Welcome to the forum. Hope someone who used both can chime in 

[Jacek]

There is one direct comprison on vimeo, may be helpfull:

 

[Germy1979]

ugh.  Everything has a blue tint to it from everything I've seen online from the A7S.  I don't know what it is, but I see a serious lack of reds in everyone's grade.  Greens look blue-ish, skin looks un-naturally pale and "milky", and the whole thing just looks...cold.  Is this how it's supposed to look?

[Andrew Ray]

Germy1979, much of Sony's color tilts towards the cold, especially when compared with Canon. If the a7s had internal 4k, I'd overlook that flaw in a second and move from Canon to Sony because of the tremendous value the a7s presents versus the C100.

[fuzzynormal]

Canon's always been warm and Sony's been cool.  This goes back decades--in my experience anyway.

[Guest d5f8611fa423d0e628c016f9d5c93b47]

To me, this A7s issue is not just about colour temperature. It's about how weak and pastel the colours appear. 

 

I'm very far from a tech-head, but I wonder if to allow for extracting so much DR from a compressed codec Sony have stretched the colours too thin? Also contrast can affect the impact of saturation so that might have something to do with it?

 

Or perhaps it's just that everyone who has uploaded a video has been so focused on showing off the impressive DR, they forgot to think about contrast and colour! I doubt it though ...

[Rungunshoot]

To me, this A7s issue is not just about colour temperature. It's about how weak and pastel the colours appear. 

 

I'm very far from a tech-head, but I wonder if to allow for extracting so much DR from a compressed codec Sony have stretched the colours too thin? Also contrast can affect the impact of saturation so that might have something to do with it?

 

Or perhaps it's just that everyone who has uploaded a video has been so focused on showing off the impressive DR, they forgot to think about contrast and colour! I doubt it though ...

 

Matt, I think you nailed it here.

 

Most of the footage we've seen has been shot flat in order to show off the mighty dynamic range of the A7s.  But when you spread 13 stops of range over an 8-bit gamut, you sacrifice color fidelity.

 

I'd like to see someone set up the A7s for a punchy in-camera look that maybe sacrifices 2 stops of range but gains back color fidelity, especially in the flesh tones.  I'm sure the camera can do it.  I've extensively used the NEX-5n, RX100 and RX10, and those low-end cams produce beautiful color.

 

In response to Andrew's original post, I think the A7s is just as sharp as C100, but the C100 is a much more usable camera in the real world mainly because it doesn't face the horrible rolling shutter issues of the A7s.  And C100 has a long-lasting battery, whereas the A7s battery appears to drain very quickly.  Plus, C100 has that magic color science that makes Canon cams sing regardless of their technical inferiorities.

[Guest Ebrahim Saadawi]

Yes I think what we're seeing with the A7S is the problem of S-log rather than the camera.

Using a log profile, with an 8 bit codec is a recipe for disaster.

You try to regain contrast, and the luma breaks up in bands with a strong S curve simply because there isn't enough luma values to withstand that heavy pushing.

You try to regain saturation, from an 8 bit, gray image, so you push them too hard and there isn't enough chroma in the first place, you end up with thin, artificial, banded colours.

I've seen this before in the Canons where we were backing in an inverted S curve + taking away saturation, by using Cinestyle. When you took that image and started grading, it broke up and fell apart.

[jcs]

Slog2 gamma with Cinema Color Mode worked well in low light for a recent fashion shoot. There were a wide variety of skintones and very challenging lighting- red and blue lights mixed with white, etc. I'll post some footage in the next few days.

[Guest d5f8611fa423d0e628c016f9d5c93b47]

Slog2 gamma with Cinema Color Mode worked well in low light for a recent fashion shoot. There were a wide variety of skintones and very challenging lighting- red and blue lights mixed with white, etc. I'll post some footage in the next few days.

 

I think that in general I've found the colours in the low light A7s footage I've seen more pleasing and punchy than daylight footage. Not sure though.