S-Log2 3g-sdi 4k and alphatron

timmytimetravel

timmytimetravel

Well-known member
Interesting.

Got my FS700 back from Sony service in Australia today having had the 4k fpga update. When set to HD the sdi out into my alphatron showed something it has not before. "3g-sdi 1080 50p" when video out was set to 1080p.

Previously I am 90% certain (someone with an alphatron back me up) that the max you could set was 1080i. (even when recording 1080p).

When recording set to RAW mode (and simultaneous raw+hd), same deal 3g sdi recognized but all I got was snow in 4k, and in 2k I got a 3/4 green screen, and snow up the top.

Fun to monitor then, I guess I read I guess you take your monitoring tap off the external recorder.

Im sure this is all expected, eg the 3gsdi is really kind of "unlocked" now.

I'm sure I recall in the early days it was outputting something special on sdi when in SSM mode, that people were able to record off an external recorder, but may have been semi useless due to 3g sdi not being unlocked?

I'm sure there is no advances there, as even the 2k signal would be specially encoded.

BUT, I notice now in record set "HD" mode in SSM 200fps. The alphatron now shows 3gsdi.

Can someone with an alphatron and not fw 3, confirm in SSM it still does not show 3gsdi.

And can someone recall a thread or details about what was put out during SSM that was so special and recordable?

I don't have an external recorder, waiting for a 7q, so I am not sure I could test something anyway, but might be able to borrow something. See if now that SSM is putting out 3gsdi maybe we can get ???? what was it... (that is without the pricey recorders, some sort of free lunch ;) )
 
I tried outputting 2k and 4k to my Pix240i. During RAW mode, screen diagnostic shows 1080p 10 bit, but, no picture. Just green hash. In HD mode, Pix240i records an image at 1920x1080. Not sure what downscaling process is being used.
 
Interesting...

I think I recall what I was thinking of now. It was this article

http://www.xdcam-user.com/2012/06/uncompressed-slow-mo/

Whereby if you had a Gemini or other 3g-sdi capable recorder you could get uncompressed 240fps over sdi while ssm was activated.

I presume that means with continuous 2k mode, it MIGHT be able to take that feed? Maybe not. I was kindof hoping somehoe when ssm was going and now it seems to be putting out 3g-sdi signal to alphatron that would somehow translate to the ability to get something like a hyperdeck shuttle to record 10-bit during ssm or something. I am sure that's not the case, and the firmware does not change anything for the cheaper recorders.. I would so buy a shuttle 2 in a heartbeat if we could get 10-bit to it. Imagine that 10-bit slog2 to a $300 recorder. Its possible but not possible :)
 
The 3G-SDI recorder must be able to do 60p. The stage that it records is when you're watching the "playback" (writing to the SD) from the buffer. The Hyperdeck Shuttle doesn't record 60p, so you wouldn't be able to capture this buffer.
 
jshbckr said:
The 3G-SDI recorder must be able to do 60p. The stage that it records is when you're watching the "playback" (writing to the SD) from the buffer. The Hyperdeck Shuttle doesn't record 60p, so you wouldn't be able to capture this buffer.
Click to expand...

Does this statement from dan at cd re oddessy make any difference? Maybe the external playback is at 30?
I'm guessing not as even if it was now less than 60p, you would need a cheaper recorder that could do 4k even to try and record that buffer?

"The upgraded FS700 has a special 4K mode, which supports 120 fps recording, for around 4 seconds, to their internal buffer, to be played back at a slower speed to an external recorder such as ours.
 
I was addressing your thought that perhaps the Gemini/other 3G-SDI recorders could record the continuous 240fps based on the fact that they can record the 240fps buffer. I was clarifying that the reason they can record the buffer is because the camera plays back the buffer at 60fps (which is why buffer playback takes about 20-25 seconds to play back the clip that was 7.8 seconds real-time), so therefore a 60fps recorder would be capable of capturing it--it is playing back at a frame rate that it is made to capture. However, continuous 240fps would be coming out the SDI at the full 240fps. A 60fps recorder wouldn't be able to capture this.
 
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