GH4 Blackmagic Video Assist

R

RedChalice

Active member
What are your guys' thoughts on this monitor/recorder by blackmagic design? It's only $500 and is a 1080p monitor, as well as an HD recorder. I assume that this would appeal greatly to GH4 users because they can convert their UHD footage into 10 bit 4:2:2 directly within the recorder.

I was considering buying an Aputure VS-2 7" monitor for $240, but I might just hold out until this comes out (which should be end of July)

thoughts?
 
I was considering one myself at that price point, not sure it can down-covert UHD and record at the same time, that would be an impressive feat. It only states that it can monitor UHD. I imagine the incoming signal would need to be HD in order to record it? Nice to see that it records to inexpensive media.
 
If u set the gh4 to 4k it outputs hd downsized from 4k out the hdmi. So this is a very good option specially once the v-log rolls out
 
i've read that the recorder will indeed downconvert the UHD in 1080.. should be out in a few weeks so we'll know for sure soon..
 
Since the Gh4 records 4k internally, would the Video Assist render an inferior quality image because it records only 1080p?
 
RedChalice said:
I was considering buying an Aputure VS-2 7" monitor for $240, but I might just hold out until this comes out (which should be end of July)
thoughts?
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I have the Aputure VS-3 (I think!), not sure what the difference is, but the VS-3 is more or less useless. Not worth $240, that's for sure!
 
emweb said:
Since the Gh4 records 4k internally, would the Video Assist render an inferior quality image because it records only 1080p?
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Well that kind of depends.

On one hand no because the video is 1080p 10bit and recorded with ProRes at a visually much better level of image compression. Its kind of like choosing to shoot 1080p intra with the Gh4. Yeah its lower resolution but each frame has a more consistent level of quality no matter how complex the scene is.

On the other hand yes because well it is lower resolution. Plus while the recorder is 4:2:2 color if you down convert the 4k in post you can end up with HD at 4:4:4. So shooting 4k in camera can actually yield more color information even for a HD edit. You are however limited to 8 bit in this situation.

So really if you are mastering and delivery at HD it really comes down to frame by frame image compression and 10bit vs 4:4:4 mastering color. Pick your poison.

The ideal situation is of course to record 4k externally at 4:2:2 10bit. This gives you the best of both worlds with none of the negatives. Well except for file size and record price that is.
 
Thomas Smet said:
Well that kind of depends.

On one hand no because the video is 1080p 10bit and recorded with ProRes at a visually much better level of image compression. Its kind of like choosing to shoot 1080p intra with the Gh4. Yeah its lower resolution but each frame has a more consistent level of quality no matter how complex the scene is.

On the other hand yes because well it is lower resolution. Plus while the recorder is 4:2:2 color if you down convert the 4k in post you can end up with HD at 4:4:4. So shooting 4k in camera can actually yield more color information even for a HD edit. You are however limited to 8 bit in this situation.

So really if you are mastering and delivery at HD it really comes down to frame by frame image compression and 10bit vs 4:4:4 mastering color. Pick your poison.

The ideal situation is of course to record 4k externally at 4:2:2 10bit. This gives you the best of both worlds with none of the negatives. Well except for file size and record price that is.
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I don't think there would be a difference in quality between: downconverting 4k to 8 bit 1080 in post, or downconverting 4k to 10 bit 1080 within the recorder.. If anything I'd imagine the image to look better in 10 bit 1080 via recorder.
 
Setting the GH4 to 4k and downconverting to 10 bit 4:2:2 from the camera yields fantastic results using an external recorder (I have a ninja blade). IMHO, I don't believe that downconverting 4k in post will give you 4:4:4 color. That was part of a speculative article on EOSHD, and for what ever reason, appears to have gained currency in some quarters. My 02..
 
mr bill said:
Setting the GH4 to 4k and downconverting to 10 bit 4:2:2 from the camera yields fantastic results using an external recorder (I have a ninja blade). IMHO, I don't believe that downconverting 4k in post will give you 4:4:4 color. That was part of a speculative article on EOSHD, and for what ever reason, appears to have gained currency in some quarters. My 02..
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it is not speculation but simple science. If you take an image and scale it down you resample all the pixels and are effectively going to get an image that looks and acts like 1080p 4:4:4. no magic here at all but a simple situation of ratios and converting from 4k to HD basically cuts out the missing pixels. Some people tried to make it seem like magic with fancy articles but its just image sampling 101. Same is true for any format. Convert HD to 960x540 and you end up with 4:4:4. convert 1280x720 to 640x360 and you get 4:4:4. Take a photo from the web badly compressed and scale it down to 1/4 res and it looks much better. again just part of basic image sampling processing. In fact it is impossible not to get better color ratios by scaling down an image unless you happen to then save it to a highly compressed format. We use this method to clean up web graphics all the time. If a client gives me large but crappy looking images they always turn out looking a million times better by scaling them down. thats just how image processing works and is an averaging of surrounding pixels.
 
It's not going to be identical to an original 4:4:4 capture, though. Resampling is an averaging, which isn't the same as an original.

(I'll grant that it's better than nothing)
 
this is getting too technical so lets simplify with one question:

will this blackmagic recorder produce better quality images by downconverting your 4k into 10 bit 1080, or is it the same/or worse quality than downconverting your 4k in post (FCPX etc)..??
 
RedChalice said:
this is getting too technical so lets simplify with one question:

will this blackmagic recorder produce better quality images by downconverting your 4k into 10 bit 1080, or is it the same/or worse quality than downconverting your 4k in post (FCPX etc)..??
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That's a good question! The definitive answer will have to wait for in-hand reviews.
 
Dan Keeble said:
This is shipping soon.
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It better be.

What I find odd is that the monitor is shipping soon and yet there hasn't been any reviews of the actual working unit. BMD seems to be keeping this monitor very close to their chest for whatever reason. I just find it odd that they wouldn't send out a unit or two to reviewers to generate some buzz about the monitor once again.
 
It's out and no reviews. I'm hoping in a day or two we get some feedback. Seems like a good way to go with a GH4 shooting 1080.
 
FatDaddy said:
It's out and no reviews. I'm hoping in a day or two we get some feedback. Seems like a good way to go with a GH4 shooting 1080.
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Yeah, I couldn't wait, and just got a Ninja 2. I'll keep it for a few months and then sell it and get a Ninja Assasin. From what I could tell, the video assist didn't support waveforms or false color, so that took it off the table for me, as I needed something to help me expose V-Log better. And the adjustments in firmware 2.4 don't really help that much.
 
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