Hv40 fiddling

[Matt Chandler]

Hi everyone.

Been using the nanoflash successfully for shoot 60p stuff - shooting elements and water tank stuff. good fun.

I recently tried using a Canon HV40 with it - however im having some issues.
Im hooking it up via HDMI to the Nano and no matter what i set/do on either the Nano or HV40 - the signal displayed on the Nano is alwasy 59i - 30.
If i enable PSF on the nano - the nano displays 29p. not very useful

I have all latest firmware updates.

anyone played with this kind of setup?

[Matt Chandler]

I wasnt too specific actually was i ?.......

Im having a little trouble getting the right feed and framerates from HV40 into the NanoFlash.

No matter which 'mode' i set the HV40 to, the nano only ever reads '59i 0030'
I know the nano doenst currently support Pulldown for an HDMI signal (look forward to next firmware) - but i am not so sure about how it is recording the 24p in a 60i wrapper.
After applying a 3:2 pulldown to a recorded test clip, it still has interlacing artifacts.

Any pointers will be appreciated

[Aaron Newsome]

Hi Matt. I'm sure you are going to find out soon enough, so I'll just tell you right here. No matter what mode you set your camera to, the signal coming out of the HDMI port will be the same 60i.

I'm thinking you'll need either something that knows how to pullup the frames on the fly (nano flash when it's ready) or remove the pulldown in post.

[Matt Chandler]

Hi Aaron

Thanks for reply - yes ive read up about the HDMI only outputing a 60i signal.
Problem is i cant tell if the Nano is capturing the 24 in the 60i wrapper or not.

Im using ProspectHD by Cineform to convert the clips/remove pulldown, but this is creating some artifacting and jittering...leading me to believe the signal the nano is recieving/recording isnt 24p in a wrapper. The camera is set to this mode however.

[Aaron Newsome]

Sorry, I didn't address the second part of your post. If you take the footage you've recorded and step through it frame by frame, you'll probably see that not every frame appears to have interlacing artifacts. You'll probably notice that the footage has 3 frames that appear to be progressive, followed by 2 that appear to be interlaced, followed by 3 frames that appear to be progressive and on and on until the footage is done.

This 3, followed by 2 is the 3:2 pulldown pattern.

That's how they pack 24p into a 60i container, with the pulldown. Let's say you have four 24p frames.

[A] [B] [C] [D]

that's the four frames. if you put these four frames into a 60i container, first of all interlaced footage has 2 fields, so below, you'll see two letters inside the brackets. Those four frames of 24p footage ends up looking like this in a 60i container:

[AA] [BB] [BC] [CD] [DD]

You can see that we've made 4 frames into 5 frames. Each frame has two fields and two of the 5 frames have fields made up from two progressive frames. Those are the two frames you probably see interlace artifacts.

Is this making sense?

[Aaron Newsome]

Originally Posted by Matt Chandler

Hi Aaron

Thanks for reply - yes ive read up about the HDMI only outputing a 60i signal.
Problem is i cant tell if the Nano is capturing the 24 in the 60i wrapper or not.

Im using ProspectHD by Cineform to convert the clips/remove pulldown, but this is creating some artifacting and jittering...leading me to believe the signal the nano is recieving/recording isnt 24p in a wrapper. The camera is set to this mode however.

Look through the 60i footage frame by frame. You'll need to do this to be sure. From the pattern I posted above, you can see that if your pulldown removal software chose the wrong frame number to start the pattern, you're resulting footage would actually look worse than when you started.

In order for pulldown removal to work right, either the software must identify the pattern correctly, or you must be allowed to specify the pattern manually.

Either way, when you step though both footages, you should be able to very easily identify the pattern and know when the removal is working or not.

[Matt Chandler]

hi again

thats for the quick breakdown - yes im definetly getting this pattern. thanks for the tip to spot it. im getting 3 progressive and 2 interlaced. great - so the nano is picking the signal out/recording it correctly.

Problem is removing it. seems to be creating some weird things....

[Dan Keaton]

Dear Matt,

Even if you are using our latest firmware, with Pulldown Removal, we do not currently support Pulldown Removal for HDMI, just the HD-SDI input.

This will change as soon as possible.

Arron was right, of course, about Pulldown Removal. This is what you need as your 24p is padded out with duplicate frames to make 60i. If you turn on PSF, it will show as 29.97 frames per second.

What you need is what we need to do, add Pulldown Removal for HDMI. Our plans are to add this soon.

[Matt Chandler]

Greetings Dan

Yes ive read up over the forum and all the excellent postings that thsi shall be implemented soon. Look forward to that. Certainly would be handy as an automated feature.

Thanks to Aaron pointing out how to spot the pattern, ive realised how to remove the pulldown, as sometimes it appears the clips/recordings begin/missout a frame/field - therefore throwing out a cineform conversion error on the clip.

A workaround that seems to be working well for me is to import the raw MXF file from the Nano into a 60i premiere project, export at those settings (29.97) - then run the clip through HDlink with the 3:2 pulldown option. Works great now. Without running it through premiere first and creating a CFHD file - the pulldown seemed to messabout a bit.

Thanks for help so far. Great forum.

[Aaron Newsome]

Matt, pulldown removal is pretty solid "IF" your software picks the correct pattern to remove it. This one of the things I like about After Effects, it give you both automatic detection (while telling you the pattern it detected), and you can specify the pattern manually.

Whatever you do, don't use psf on the nano because that would be wrong and I would imagine you would mess up the footage all together. 60i needs to be recorded as 60i and the pulldown removed later, or when the nano supports it, remove it on the fly.

[Matt Chandler]

Greetings again fella's. T'was late last night and i neglected to mention some other stuff.

Adding somewhat to my period of HDMI confusion - is that i HAVE captured 720p at 60fps via the HDMI. This would appear to contradict the HDMI signal that we have discuseed.

I do alot of vfx stuff mainly and have used the Nano for allsorts/ Ive got a big water tank set up/lit so we can shot some 60fps cloud tank kinda stuff...red inks etc. Im using this together with fluid simulations for vfx projects at work.
- lately capturing 60p at 1280x720 via HDMI.

Though isnt this impossible? Apparently? Or did i get lucky with the small camera im using.

I have been using a Xacti HD2000 which has true 60p capability. Not bad for a £300 consumer cam. However, there isnt an HDMI connection on the camera itself, but on the dock/port that comes with it. Its a little cumbersome to connect it all up so that it streams out, as the dock isnt really designed to be on the camera while the camera is in use....but it works. As long as the video format is set correctly to 720p output on the camera - the Nano reads this rate correctly and captures.
There must be something happening with the dock to allow this.

Im really interested in seeing if anyone else has managed/happened across this.

[Aaron Newsome]

Wait a sec, your HV40 does true 60p?

[Matt Chandler]

Sorry if i didnt make it clear enough in my post. Im talkign about an additional camera aswell - a SANYO XACTI - these have 60p capabilites. i have been shooting water tank/ink rolling around elements in 720p60 and captured into the nano. looks great

[Dan Keaton]

Dear Matt,

We fully support 720p60 / 720p59.94.

We do not support 1080p60/59.94 as this is beyond the spec/data rate for single-link HD-SDI.

[Matt Chandler]

Hi Dan,

Ok yes - thats what i thought. So what will the overcranking firmware feature add to the Nano. What you specified seems to already be in the Nano.

Im heading waaaay back in this forum and reading it from the first posting before i ask any more dumb questions