HD-SDI + NanoFlash with 1080/30p or 1080/24p

[James van der Vyver]

I purchased a NanoFlash unit to use with my NX5U. I have no problems recording 1080/60i, however, when I set the camera to 30p or 24p the output options for the SDI are 720p, 1080i and 480i - no 1080p options. Even when I select 720p on the SDI output (camera is set to 1080/24p) - the signal on the SDI is 30fps.

Does anyone have any experience with this?

[Victor Wilcox]

NX5U HD-SDI Output Question : Sony NXCAM

"Re: NX5U HD-SDI Output Question
by Scott Frace on Nov 11, 2010 at 8:01:15 am

The HD-SDI output is 4:2:2 sampling and so is the HDMI output. I talked to Sony representative and they explained that the HD-SDI outputs the highest quality possible from the camera, however if you are shooting anything other than 60i, it goes through a 3:2 pulldown that must be removed in post. There is no loss of quality when doing this, it's still the 24p or 30p footage just hidden in a 60i stream since that is all that can be sent through HD-SDI. I hope this answered your question."

[James van der Vyver]

Thanks Vic - tried it and it worked.

[Alister Chapman]

When shooting 1080p30(1080p25) the vast majority of cameras will out this as 30P(25P) contained within a 60i(50i) stream. This is because in the original specifications for HD-SDi there was no allowance for 1080p, only for 1080i. This signal is called PsF (Progressive Segmented Frame) and is quite normal for 30P and 25P as the standard way to send these these modes over SDI.

The NanoFlash has a check box for PsF input. If you check this box the PsF input will be recorded correctly as progressive files on the CF cards. However it is important to understand that the NanoFlash cannot differentiate between a 30P PsF signal and a true 60i signal, so if you shoot 60i you MUST make sure that the PsF box is unchecked so that it does not record your interlaced output as progressive.

When you shoot 23.98 on the NX5 the output is 60i with pull down. The NanoFlash again has the option to remove this pull up buy checking the Remove Pull Down option the 23.98P signal is extracted from the 60i stream and recorded as a 23.98P stream.

[Chris Adeyefa]

Originally Posted by James van der Vyver

Thanks Vic - tried it and it worked.

Hey James can you post some footage captured with the NanoFlash? Maybe some before after or side by side comparisons? I'm considering getting a nanoflash or the new ninja that is coming out. I want to weigh in the benefits and weather its worth the cost. Also what are the comparisons to just purchasing a capture card like the BlackMagic design decklink HD extreme. Obvioustly the Nano would be a portable solution but are there any other advantages over a standard capture card?

[Marty Jenoff]

I recently learned of this while researching the AJA Ki Pro. I'll be recording in 1080/30p but the cam exports it as 60i.

Victor, you said "it goes through a 3:2 pulldown that must be removed in post" How do you do this?

I haven't looked into the NanoFlash but I'll check it out if it can do the trick.

[Victor Wilcox]

I was quoting the referenced post. I don't have a NanoFlash. Maybe some day.

[James van der Vyver]

Originally Posted by Alister Chapman

When shooting 1080p30(1080p25) the vast majority of cameras will out this as 30P(25P) contained within a 60i(50i) stream. This is because in the original specifications for HD-SDi there was no allowance for 1080p, only for 1080i. This signal is called PsF (Progressive Segmented Frame) and is quite normal for 30P and 25P as the standard way to send these these modes over SDI.

The NanoFlash has a check box for PsF input. If you check this box the PsF input will be recorded correctly as progressive files on the CF cards. However it is important to understand that the NanoFlash cannot differentiate between a 30P PsF signal and a true 60i signal, so if you shoot 60i you MUST make sure that the PsF box is unchecked so that it does not record your interlaced output as progressive.

When you shoot 23.98 on the NX5 the output is 60i with pull down. The NanoFlash again has the option to remove this pull up buy checking the Remove Pull Down option the 23.98P signal is extracted from the 60i stream and recorded as a 23.98P stream.

Thanks for the further clarification. Only problem I now encounter is that when I select the "Remove 3:2 Pulldown" option on the nanoflash - it looses the signal and reports - "check 3:2 video src." When I uncheck it - signal is back. (Camera is set to 1080/24p and PsF is checked on the nanoflash) - any insight with this?

[James van der Vyver]

Originally Posted by Chris Adeyefa

Hey James can you post some footage captured with the NanoFlash? Maybe some before after or side by side comparisons? I'm considering getting a nanoflash or the new ninja that is coming out. I want to weigh in the benefits and weather its worth the cost. Also what are the comparisons to just purchasing a capture card like the BlackMagic design decklink HD extreme. Obvioustly the Nano would be a portable solution but are there any other advantages over a standard capture card?

Hey Chris. I will capture some in the next day or 2 and prepare a side by side comparison.

[Chris Adeyefa]

Great! Look forward to seeing them

[Yannick Hausler]

Brilliant, me too!

[Alister Chapman]

You don't want PsF selected when using 24P as in this instance the output is interlaced. Confusing I know!!

I did a comparison of the EX and Nanoflash here: XDCAM-USER.com Convergent Design NanoFlash

[Chris Adeyefa]

James do you have a vimeo channel or is there any way to view some of your NXCAM 4:2:2 footage. Its very rare to find someone with a nanoflash + NX5. I want to see the differences in capturing uncompressed. This camera has a very powerfull feature and nobody really seems to be utilizing it from what i can see so far.