Welcome to our community

Be a part of something great, join today!

Log in
  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Output delay on SDI vs. ARRI

Brett Harrison

Brett Harrison

Well-known member
Joined
Oct 15, 2012
Messages
1,083
Reaction score
0
Points
36
Location
Melbourne, Australia.
I’m a huge fan of RED. However I rely on the SDI for operating remotely, so I have a preference for ARRI cameras because I believe the are tangibly faster on their output.

On a RED I can flick my fingers into the frame and out again before they show up on the output from the SDI, on ARRI it isn't possible.

There’s a world of missed opportunities in that time difference.

Would love to hear people’s thoughts and recommendations.
 
Last edited:
If you're talking about general HD-SDI monitoring, I'm not experiencing a delay that inhibits work in any way. It can be focus pulled from wirelessly for instance.

If you are talking about the delay when you are pinching to Magnify, RED cameras are literally changing the recording format/resolution to 100% (depends on screen size I believe) which causes that delay.

One day, likely when there's a new brain and some other advancements 100% magnify in and out (and the ability to move that reticle while zoomed in) will be possible. At the moment it is part of the ecosystem. If we ever get a 4K or 8K broadcast module and a receiving monitor that takes a 4K or 8K signal and magnifies in, that will be part of a solution.

Hard to tell at the moment if that's on the horizon again for RED. I have a feeling it is, but they haven't hinted at an Expander or Module just yet. It will be much more of use to individuals in 2018-2020 in particular either way.
 
I’m talking about the additional ~5 frames of delay that the RED SDI has compared with the ARRI. You can see this by flicking your fingers from outside of frame and into frame and out again. I’ll post a video to demonstrate. This amount of frames has a tangible effect on operating - especially remote operating where unpredictable action is common.
 
I am also curious about this, as it has been a problem from time to time on set. It seems, for me, to vary from monitor to monitor. Flanders have a serious lag but smallHD seems to be a little better.

Any thoughts?
 
I had to stop using my (2) Flanders 24" (CM240's) monitors because of the delay. They were horrible- almost a second behind. Drove agencies nuts as the sound in their Comtecs (headsets) was always way ahead of the picture. The better equipped audio guys could actually "slip" the audio 15 frames to their headsets which was a huge help. And yes, the FSI monitors were set to "fast" but it was still not acceptable.

Anyway, I'm now using SmallHD 24's and 17's and have no issue with delay.

I've never had any problems with the SDI output on any of the RED cameras manufactured to date of being to slow. There might be a frame or two behind "live" but not enough to cause any major issues with focus pullers working off a monitor.


Alex
 
Have you all set the HD-SDI output to 59.94 Hz? If you have it set to 23.98 Hz there is a much longer delay than at 59.94. Doesn't change the 24p look, but it's pretty close to sync.
 
I usually keep it on AUTO to avoid tearing and frame drops on the output signal.

What's your experience using mismatched rec fps / mon out fps?
 
On the Flanders screen we have there is a setting like 'show PSF as progressive' or something like that... basically when feeding from a red camera it has to be off or there is a big delay despite the setting referring to something that shouldn't effect a progressive signal (like Reds)



Alexander Mitchell said:
I had to stop using my (2) Flanders 24" (CM240's) monitors because of the delay. They were horrible- almost a second behind. Drove agencies nuts as the sound in their Comtecs (headsets) was always way ahead of the picture. The better equipped audio guys could actually "slip" the audio 15 frames to their headsets which was a huge help. And yes, the FSI monitors were set to "fast" but it was still not acceptable.

Anyway, I'm now using SmallHD 24's and 17's and have no issue with delay.

I've never had any problems with the SDI output on any of the RED cameras manufactured to date of being to slow. There might be a frame or two behind "live" but not enough to cause any major issues with focus pullers working off a monitor.


Alex
Click to expand...
 
Matthew J said:
Have you all set the HD-SDI output to 59.94 Hz? If you have it set to 23.98 Hz there is a much longer delay than at 59.94. Doesn't change the 24p look, but it's pretty close to sync.
Click to expand...

I did try this but it's definitely not as fast as the LCD, which is pretty much as fast as an ARRI - though I think the ARRI is still faster on the SDI than the RED's LCD.

You can test this by filming the LCD with and SDI next to it, shoot something into frame and count how many frames after the LCD the SDI screen displays the object - it's at least 5 frames, perhaps more.

I love RED images I just can't operate as effectively from the SDI out - which spoils things for remote video or 3rd party monitors.

Would love a public comment from someone from RED on this - especially if that word is 'you're doing it wrong' would love to be wrong about this.
 
I've never had any sort of delay via SDI that has gotten in the way of doing any mission critical work. Appreciate that doesn't help any but hopeully there's some setting somewhere that will sort out your problems for you.
 
You must log in or register to reply here.
Back
Top