Your advice on GH4 vs A7R II (and others)

[adrjork]

Hi guys,

I’m searching for an advice about a video-camera. Just a pair of questions.

I’m following a “video-composition for music” course in the Conservatory of Trieste, and my Prof says that I have to choose and buy a camera to begin shooting (and I’m a beginner).

I try to make the point about the specs I probably really need:
1. Low Light: I will surely shot exclusively in natural light, without reflectors or led-panels, so I need a fast camera;
2. Dynamic Range (and bit depth): working in natural light I’ll need to grade a lot in post;
3. Sharpness: I will do composing, so the image has to be well detailed;
4. Hybrid: it would be better if the camera could do stills too;
5. Workflow: I’d like to work with video-files that don’t require a super-priced-monster-mac (I’m a mac user).

After various researches and comparison tests from internet, I’ve found 4 competitors: GH4R (with V-Log), A7S, A7R2, BMCC2.5k.

GH4R vs BMCC2.5k
I’ve seen that BMCC2.5k has a wide and filmic 13 stops Dynamic Range, but it seems to me that it’s not a low-light champion, and no stills at all. On the other side, GH4 is a real hybrid camera and it outputs sharp 4K, yes it has a narrower 10 stops Dynamic Range but the new V-Log L profile should add 2 stops, and I can link the 10bit HDMI output directly to the new Atomos Assassin to match the 10bit 422 Prores of the Blackmagic, but in 4K!
So GH4 wins! (BUT the workflow of HD 10bit Prores is smoother than 4K 10bit Prores… Surely HD doesn’t need more than an iMac, while - this is my first question for you guys - grading or composing 4K requires a big bad Mac Pro, isn’t it?)

A7S vs A7R2
A7S is most of all video oriented (with 12MP the stills are really small for print) while the A7R2 is another real hybrid that makes really big stills. I’ve seen a low light comparison between A7S and A7R2 (https://www.youtube.com/watch?v=G8eaWln57cc) and it reveals that up to ISO 12800 the two cameras are pretty similar in noise level.
So for my needs I think A7R2 is the winner.

GH4R vs A7R2: The showdown
After a comparison test between the two cameras (http://www.eoshd.com/2015/08/panasonic-gh4-vs-sony-a7r-ii-low-light-speed-booster-shootout/) Andrew Reid says GH4 is not so far from A7R2… Well, I’ve seen a big difference: A7R2 has a wider Dynamic Range and seems to be almost noise free, but this comparison lacks something:
1. GH4 was tested without V-Log L profile (and this should improve the GH4’s DR by 2 stops!);
2. Both footages are internal codec, while I’d would be curious to see both footages taken with Atoms Assassin: because GH4’s HDMI outputs 10bit, while A7R2 outputs only 8bit.
So, who would be the winner if GH4 were equipped with V-Log L and 10bit Prores?
That is the second question of you guys.

Thanks a lot for your appreciated help.

[Morgan_Moore]

As I said on the other thread probably best start with a $500 used DSLR with a mic input... or Gh2?

(you do not specify how much importance sound recording is in “video-composition for music")

This is a course.. you have no need for image quality! You have no clients to please.. you just need to compose images and cut them to make stuff... by the end of the course you will have learned which camera you need.

Buying a camera is like a car.. some are good offroad, some small enough to park in the city, some are super fast and high luxury.. the small one might fit your needs even if you have a huge budget, that fast one may be no use if you live up a snowy mountain track.
--

Some comments on those cameras..

BMC are honest cameras.. a chip in a box that writes to a card and not much more!

nice images
simple to understand
properly sharp.. if it says 2.5k it is 2.5k, if it says 4k it is 4k.
Low light.. if you properly expose at 800 they are fine.. most people under expose and get noise.. but 800 is 800!
4k has global shutter which gives a much nicer look
audio is through an annoying and expensive box
no battery changes suck for some (I run off external batter and see the onboard as a bonus!)
onboard monitor useless in the sun
sdi only - no cheap external monitors
BMC are 10 bit or raw.. 10bit is a big step from 8bit
BMC make pretty pictures.
Proper tripod holes (two)

GH4
weak above 400/800 ISO
onboard cheap media
Yag box brings proper audio monitoring quite cheap and neat
4k makes OK 1080 video.. some say one can generate 10bits through sub sampling.. hmmm
Proper tripod holes (two with yag box)


A7
Sony are a bag of tricksters.. the spec is not the spec..
Fullframe.. unusable too much 'jello'
Slo Mo.. unusable too soft
8bit Slog.. should deliver high DR but is really weird to colour
high ISO - yes a win
One tripod hole.. very crappy to have the camera come 'undone' all the time!
Adding XLR is a very silly box,
Sony cams are not cheap!

BTW.. I own a GH4 and shot a feature film on a bmc 4k, I have no hands on with the A7 cameras. I also own an FS7 which is the real deal for 3X the cash.

I cant remember why I bought the Gh4 not the bmc 4k.. maybe it was money or was it the XLR input? I cant remember.

--
BTW 12mp is enough for pretty much any print IMO. Ive had billboards with the nikon D3

Im thinking panny GH2/3 - the one you can hack to make nice 1080 and costs $400?

S

[adrjork]

First of all, thank you Mr. Morgan_Moore to have given an answer full of detailed infos also to this topic.

As I said on the other thread probably best start with a $500 used DSLR with a mic input... or Gh2?

I think it's a really good idea. A pretty good machine for a beginner with HD workflow!

(you do not specify how much importance sound recording is in “video-composition for music")

It's true: "video-composition for music" might mean all and nothing, but generally refears to video-only abstract composition for contemporary-music installations or performances: for example my Prof. Paolo Pachini made this video for a music composition by Fausto Romitelli: An Index of Metals*
In this case, audio is not the matter of this kind of video-artist (that work with audio in the sense of keeping it as a point of reference, as a mute dimension, or as an ingredient apart).
BTW, I must say that I surely prefer to do have audio inputs in camera!

I appreciated a lot your comments on the cameras:

BMC make pretty pictures.

Does this mean that I can use an HD frame as a still?
This is one of my doubts: I'm not an expert at all, but I've always thought that a frame couldn't "work" as a still: different definition, different "behavior" of the camera, probably different focus and light accuracy (I don't know, I only try to image). Well, if frames are similar to still, why does a  camera shoot only 7 stills per second? I don't know, this is only a doubt.

About GH4 you say:

some say one can generate 10bits through sub sampling.. hmmm

This is important to me: I've read about external recorders (like Atomos Assassin) that records in Prores directly from the 10bit HDMI of the camera. Do you think it's not a real 10bit solution? Do you think it is better to use internal 8bit codec?

You use both BMC and GH4, and if I'd decide to buy a BMC I'd take the 2.5K. On your experience, in low-light condition, which camera does less noise: GH4 or BMCC?

*) https://www.youtube.com/watch?v=QiQ2EN20ods

[Morgan_Moore]

BMC 2.5k will make an OK 6mp(?) still but that is not that big in todays world - not really pro stills - also you cannot I dont think take individual stills just fire off some DNGs - maybe it has a slow mode like 2 FPS

But the bmc files are nice and uncompressed - so the stills are similar to an old 6mp DSLR

I used the BMC4k - those files are big enough for stills
--


10bit.. Yep I guess the external output is 10bit on the GH4 - I was saying that some say you can downsample from 4k to make 1080 10bit.

I have used my GH4 with an HD prores recorder and the files are certainly 10bit and grade very well.

Personally I dont like or trust recorders as the cabling is to flimsy for my rough camera use.

For gentle filming GH4 and recorder could be an interesting solution.

Im really interested in trying my GH4+yag+Log+4XSDI lead to record to an odessey.

--

Low light. I dont really know - both the bmc4k and the GH4 seem quite weak above 400 ISO.

S

[adrjork]

Ok, Mr. Morgan Moore, I think I made a decision: I'm going to buy the GH4.
I think to start with a GH4 and just one lens: the 42.5 Nocticron f/1.2.

When I'll feel +/- ready to begin shooting something decent, I'll buy the Atomos Shogun and a microphone (together with an cost-effective hackintosh workstation).

Just a question about ND filters: someone recommends the practical Xume Adapters kit with the Genus Eclipse variable ND filter, but other say that GH4 needs for a IR filter too when ND is on.
Do you think:
1. Is it better a non-variable than a variable one?
2. Is it better an IRND filter than ND + IR filters?
3. Genus Eclipse alone (without IR) is good anyway?

Thanks a lot.

P.S. I notice only now that this section of the forum is dead (I had to begin the topin in Motion & Video... I copy there this last post).