Going round in circles - Need Advice from IT community

Firstly, welcome!

Now, onto your question.

Frankly, I'm surprised you found that much difference between the 600D image and the 5D image. I found with the 5D that its LCD screen makes things look a lot nicer, but when you put the video onto your computer, the difference between it and video out of a 600D or similar is small.

Now, onto your options.

The GH4 is bigger and heftier than the A7s or BMPCC. The size and ergonomics of the GH4 are much more in line with what you would be used to with your 600D. The A7s reminds me very much of shooting with my old Olympus OM1, in terms of size, ergonomics and weight. The BMPCC is tiny.

The GH4 shoots 4k internally, the A7s shoots 4k via a soon to be released $2k recorder. However, 4k is far from necessary - unless you're shooting for cinema and really need your projects to be in 4k.
Both the GH4 and A7s have interface units to allow XLR inputs into the camera. The GH4 interface unit costs more than the body itself, but also adds SDI and Genlock TC. The A7s interface only has XLRs but also only costs about $800.

The BMPCC does not have great audio implementation, so you're most likely looking at some kind of external recorder.

The A7s is full frame, which is roughly the same sized sensor as the 5D. The A7s also has an APS-C crop mode which would give you a similar FOV to what you see on your 600D.
The GH4 has a smaller sensor, and also windows even more when recording video. The BMPCC has the smallest sensor of all, with a S16 sized sensor.

The GH4 and A7s both record 8-bit 4:2:0 internally. The A7s has Slog2 and XAVC-S codec (XAVC is a good codec) internally. The A7s will output 4:2:2 to an external recorder, but it will still be 8-bit. The GH4 outputs 10-bit 4:2:2 over HDMI.
The BMPCC shoots 12-bit raw internally, so you have more room in your colour grade. Whether you need that or not depends on the work you do.

The A7s has insane low-light capability. It's the king of low light. I can't think of a video camera on the market that beats or even equals its ISO performance. The GH4 and Blackmagic are not great in that respect, though the Blackmagic is worse for it. Both the GH4 and A7s allow some sort of higher frame rate capture for slo-mo, whereas the BMPCC tops out at 30fps.

The GH4 has the best battery life, which is to be expected as it has the biggest battery of the three. The A7s battery life isn't anything to write home about, but it's not bad.THe BMPCC has pretty terrible battery life. The BMPCC will get about 40 minutes of ProRes footage onto a 64gb card. The A7s shooting XAVC-S gets about 2 or so hours of footage onto a 64gb card.

The GH4 and A7s both have EVFs, and their screens rotate or slide. The BMPCC has no viewfinder, and the screen is fixed in position.
BMPCC probably has the simplest menu system of all of them.

A7s and GH4 are both very capable photo cameras as well.

Sony do not have very many full frame lenses on the market at the moment, and the ones that are, arr very expensive. Sony does have the smallest flange focal depth of any camera on the market, so you can adapt basically any lens to it. This however means you lose auto exposure and auto focus unless you buy more expensive 'smart' adapters which are quite slow focus-wise (at least the Metabones is). The Sony A to E mount adapter is quite good though.
There are a decent selection of m4/3 lenses for both the GH4 and BMPCC.


My suggestion would be to rent or borrow each of these to test out before you buy, and see how they fit into your workflow. Camera choice is very personal.

I recently made a similar decision - was looking at GH4, BMPCC or A7s as a replacement for my 5DmkII.

I ended up choosing the A7s, but that choice was influenced heavily by my current needs. I've stopped shooting for clients so I'm the only one it needs to satisfy, and the aesthetic of A7s just spoke to me more than the other two. This was the way I ended up ranking them:

GH4 - first choice of the three if I were still shooting commercial work, due largely to panasonic's focus on ergonomics/functionality for video use, and also because the on-board 4k would be very useful in interview situations.

BMPCC - first choice for narrative work if budget was a primary concern. Trading off usability for a decent sensor backed by the best codec of the three, at the lowest cost. Low light isn't great, but it's not as bad as it seems if you're willing to put some time in in post - because of the codec I'd estimate it has room to underexpose by at least two stops (pushing the max 1600 ISO to 6400), but you'll also have to factor in noise reduction at that level in order to match the GH4.

A7s - my choice because of the overall look. It's really a combination of the dynamic range and low light capabilities, the way it renders noise and highlights, full-frame sensor, etc. It's somewhere in between the other two in terms of functionality/ergonomics, not as good as the GH4 but better than the BMPCC. As Jax noted lens selection is very limited if you have any interest in autofocus/exposure/stabilization, but that wasn't a concern for me as I prefer fully manual lenses and will probably just put together a set of the e-mount rokinons for most work.

So based on that ranking I'd have gone with the GH4 if I were in your situation. The only wrinkle in that is that if you're doing weddings there's a strong argument to be made for the A7s purely based on it's low light capabilities. It's not as good a camera for run-and-gun style shooting as the GH4 though, so if you're choosing only one you'd have to look at the balance of your work and weigh how often the low-light would be a significant factor.

Thanks for making the choice harder guys haha

I will definitely rent both before choosing, because I think how it feels is very important, I think for me all the deep technical sides are of lesser importance to some respect and the thing for me as it is a big purchase is I want to invest in something that will last me a while.

Image wise for me I am competent at editing and would like something that produces an image that if needs be can be pushed about a bit in post and not break up easily which I found with the 600D.

I am leaning towards the GH4 as it feels like more of an all rounder and would also give me room to get a couple of decent lenses. And maybe look at the A7s if i get some well paid jobs come in

I do love Sony though due to growing up with Sony Handycams.

Jax, yes I did notice quite a difference with 600D and 5Dmk3, I was shooting front row crowd at a large concert indoors, so the only light was the stage light illuminating peoples faces in the crowd and the image when put in the editing suite, was so much cleaner at high ISO compared to the 600D.

Lastly if there are any GH4 owners, have you used Samyang glass with it? And how did you get on?

Thanks guys for all the information, greatly appreciated.

Mark

I bought an A7s for the Slog XAVC, as well as the sensor size. I'm not too fussed about full frame, but you can extract APS-C which is much closer to S35mm than both the GH4 and BMPCC (I'm used to shooting S35).

I adapted my old Zuiko lenses, and a couple of old Russian lenses to it, which works great. I also have the 24-70 f4 native zoom.

It's a great little camera. A friend of mine works for a production company with a high-end wedding video arm and a corporate video arm. They shoot almost exclusively on A7s.

At the end of the day, it comes down to what camera suits your needs. What do you want most out of it? The most colour information? The smallest size? The best ergonomics? The best audio implementation? An EVF? Low light capability?

Black magic cameras are pretty great, especially at their price points. However, don't overlook the fact that you really NEED a lot of additional support gear to make them really usable. External batteries are pretty much essential for all, except perhaps the pocket cam. External audio recording is pretty essential for all. Some kind of rig is usually a good choice as their form factors are somewhat cumbersome otherwise. Also some sort of external video monitoring solution, either a screen or EVF, are pretty important as well as the screens are somewhat crap.

All of those 'limitations' and whatnot aside, they all can produce stunning images, but keep in mind too that they'll generally need a bit more work on the back end to get a good looking image, especially if you shoot raw -- you'll also need a good deal of storage, both for the camera, and for the post process.


I have the 4k, and the pocket, myself.

In your position, I would buy the a7s.

1. GH4 is great if you need to blow something up to the size of a cinema screen but otherwise the a7s is better.
2. BMCC is great because of the RAW codec. However, RAW will slow you down in the edit suite and other disadvantages such as battery life means it is unsuitable for weddings.
3. Battery life is painful on the BMCC and you need a ton of kit to go with it.

The a7s therefore ticks more of the boxes than the others and has excellent points such as low light capability which could be useful at weddings.

I have a GH4 with Samyang glass but use the 4k as I want to blow images up to cinema screen levels and don't have to worry about low light. Otherwise, would've gone for the a7s.

To answer your question about the glass, Samyang glass is outstanding for the price point. I wouldn't buy anything else use Samyang glass on my Sony VG10 as the GH4 although keep away from the lower T stops as they are too soft for cinema viewings.

.... and what did the OP finally do?

I am about to make a decision!!

My 600D died, so now have to make the jump... I would love an A7s, but I think its just out of my price range at the moment although the GH4 is a good all rounder... the low light capabilities do worry me! especially with the type of work I do! eeek