-
720p59.94 to 1080i29.97
-
[Sean ONeil] “Well after the conversion there’s only one field so there’s nothing to combine.”
It should be two fields, each field made of one p frame. 60p frames converted to 60i fields (which is 30 frames per second). Are you sure your Kona isn’t set to full frame pause? Perhaps you are only seeing a field.
True 720p60 material is 60 discrete frames per second, not 30 doubled frames (unless you shot with a varicam @ 720p30 over 60).
-
[JeremyG] 60p frames converted to 60i fields (which is 30 frames per second)
With FCP conversion yes. It becomes 30 frames per second. With the Kona conversion, no. It remains at 60 frames per second, but half of the resolution is gone because one of the “would be fields” for each frame is thrown out.
Think of it like this. Start with 720p60. Pretend the first thing that happens in both methods is that it is simply uprezzes it to 1080p60. So now there is a 1080p60 image. From there, the Final Cut method will take that and convert to 1080p30 by throwing out every other p frame, and then interlace the thing making it 1080i60 – 30 frames per second.
The Kona would take that 1080p60, and interlace it as-is making it 1080i120 (yes, 120 fields). Then it will throw away every other field, bringing it to 1080i60 – 60 frames per second.
[JeremyG] “True 720p60 material is 60 discrete frames per second, not 30 doubled frames (unless you shot with a varicam @ 720p30 over 60).”
Obviously. Isn’t that the foundation of the entire discussion? -
Hey thanks all of you for your valuable inputs. I’m somewhat clearer now that what I’m seeing is probably due to the progressive to interlaced conversion that is causing some of the clips to have “stroby” motion.
I’m from PAL land so all these 59.94, 29.97, drop and non-drop is kinda daunting for me so I’m slowly coming to terms with it.
What a wonderful industry we’re all in..eh ?
-chrispy
-
Sorry Sean, that method is totally not what is going on with the Kona.
-
[chrispy] “‘m somewhat clearer now that what I’m seeing is probably due to the progressive to interlaced conversion that is causing some of the clips to have “stroby” motion. “
Are you simply putting your 720p60 in a 1080i timeline and rendering?
That would make sense, as Sean has proven that FCP throws away half of the temporal motion.
Jeremy
-
Hi Jeremy…
Yes that is exactly what we are doing.
Is there a way to render out a 1080i version without throwing out half the temporal motion, perhaps through some conversion plugins or even a standalone conversion software ?
-chrispy
-
FIelds Kit from revision fx should do you well in a plug in form, or simply layoff with a Kona 3 or KOna3X.
-
Thanks Jeremy…I’ll give Fields Kit a try.
-chrispy
-
Interesting thread guys. I did a similar test some months ago and found the same results. I have to say Sean’s tests were more elegant than mine, though. Anyway, the result was that FCP throws away every other frame from the 60P and the Kona maps each frame to a field in 29.97i. Please let us know how the Fieldskit method turns out.
-
[JeremyG] “Sorry Sean, that method is totally not what is going on with the Kona.”
Do you have a Kona 3?
Reply to this Discussion! Login or Sign Up