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Understanding 24p, Codecs, etc.
This is my first post. Yeay!
I read countless posts and gratefully many questions have been answered over time but a THREE sticky points remain. Any help on these would be greatly appreciated.
FYI: I shoot everything using DVX-100B usually in 24p (normal mode) and export one copy for DVD and one as a mp4 file for web streaming all usually with minimal graphics and occasional green screen work.
1.) Should I continue to use the DV/DVCPRO codec given I only use the camera above? I hear all this talk about ProRes…is that really just helpful to HDV or HD users and I shouldn’t worry about it given what I shoot with and where its going?
2.) I’ve always shot in 24p (normal) and brought it into a DV NTSC timeline where my sequence settings are 29.97fps and the field set to “NONE”. I also click on the ADVANCED tab in the “QT Video Settings” section of the sequence settings and change that to “Progressive”. I figure I shot in 24p so I should change these to keep things progressive (again, I’m going out to DVD using DVDSP (and selecting progressive there too)) as well as I always make a mp4 copy for the web. MY QUESTION: Am I doing this right? Do I need to capture my footage a certain way for the “field dominance” to show “NONE” in the browser as well or do I just change it there if necessary?
3.) Finally, in the LAST response to the forum link… (https://forums.creativecow.net/thread/8/1007515)
it says:
“But if you intend to do ANY of the following:
* Put the video on the web
* Change the speed of the video
(etc..)You have to remove the pulldown BEFORE you edit, and you have to edit in a 23.976 (aka 23.98 in FCP-speak) timeline.”
I understood everything up to this point. However, “Change of speed” in the timeline using 24p (normal) footage or “exporting to the web” REQUIRES a pulldown removal first? Did I read this wrong cause I’ve never done either pulldown removal or editing in a 23.976 (23.98) timeline?
Thank you all for any help you can offer. You’re welcome to be as thorough as possible.
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5 Replies
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Hi Dave,
Your responses on this forum have helped me so much these last few months. Forgive me in advance if I’m long winded on my responses…
I actually read that article and do understand that 24p is imported at 29.97fps due to the added pulldown. Its the “progressive” thing that confuses me as it says at the end of the “Trend” paragraph:
“Recently, Panasonic (with their groundbreaking DVX100 and DVX100a cameras) and Canon (with it’s XL2) have produced DV cameras that are capable of shooting 24 progressive frames a second, bringing this once unaffordable technology to the masses.”
So, technically speaking is it progressive except for the frames that would be removed using pulldown?
That article further mentions: “Because 24p Normal uses “normal” 3:2 pulldown to embed the 24p in a normal NTSC DV video, you can capture and edit just as normal DV NTSC.”
And you mentioned “pulldown removal is essential except for the most basic projects” and…well… maybe that’s what I’ve been doing as I thought they looked fine imported, edited and exported to DVD and to the web at 29.97fps…but maybe I haven’t been taking full advantage of 24p. I’ve put clips in slow-motion and have exported to compressor as a flash file for the web (progressive) and they look fine. Why then do I have to do the pulldown and put in a 23.98 timeline? Perhaps it will look even better?
NOTE: I just used Cinema Tools just now for the first time and Reverse Telecined a 24p (normal) clip from 29.97 to 23.98 and it looks great with no visible interlacing anymore (cause the pulldown is gone…obviously). Is that what I should do to all my clips PRIOR to editing? Or do I just edit as I have been and then at the end export my whole project as a self-contained QT file and then use CT (Reverse-Telecine) to change the whole project to 23.98, then import it back to a 23.98 timeline for export?
Thanks in advance for your advice. Again, feel free to be as thorough as possible.
Also, any thoughts on my original 1st and 2nd questions?
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[Jamie Hobert] “So, technically speaking is it progressive except for the frames that would be removed using pulldown”
Not quite Jamie
the format is handled the same as 1080 HD and is called a progressive segmented frame, (PsF)
– whereas in your timeline it is progressive- but on your displays it is sent out as interlace( you cannot just magically make interlace progressive)
Take a look at this post on how this works <https://forums.creativecow.net/readpost/193/875880>
The process is just how film has been handled in projection for nearly 100 years.
gary adcock
Studio37
HD & Film Consultation
Post and Production WorkflowsCheck out
https://www.aja.com/kiprotour/Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php -
Interesting. Okay, so I just read that link and its not yet registering in my head. BUT THAT’S OKAY. I’ll get it one day, no doubt. 🙂 Thanks. Right now, I’d rather shift the focus back on this…
My real 4 questions that remain I guess are:
1.) My First Question at the start of this thread (regarding ProRes and my DVX100B 24p footage).
2.) My Second Question at the start of this thread (regarding sequence settings for 24p (and also add 24p Advanced)).
3.) From now on I’ll probably just shoot 24p “Advanced” and use the Advanced pulldown removal capture settings. When I’m done with that edit (in a 23.98 timeline) do I need to do anything again to the footage or can I just export to Compressor? (Also, I know that flash files for web should be progressive but should I/can I select “progressive” for my m2v DVD files as well?)
4.) Finally, can I take old completed projects in FCP that were shot 24p (normal) and edited on a 29.97fps timeline and go back to the timeline and export it as some sort of QT file or Uncompressed or whatever is best (never been real sure of what to do there either) and then import that into Cinema Tools and Reverse Telecine that whole project file to 23.98 to then drop into Compressor to make 24p DVD’s and web flash files (with pulldown removed)?
Anyone?
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[Jamie Hobert] “ProRes and my DVX100B 24p footage”
ProRes offers advantages for graphics and color correction, you have to test to see if it works for you, if you need the extra quality. IF you are only going to the web or DVD it may not be for you. I cannot answer your workflow- do you have a computer that can capture and playback ProRes? If you do not have current hardware and software you will NOT be able to use ProRes.
[Jamie Hobert] “regarding sequence settings for 24p (and also add 24p Advanced)).”
24pA is better- 24p causes an issue called a “mushy C-frame” that happens like this:
As for 24p DVDs – compressor will convert your footage back to 29.97 for the DVD unless you compress the file in another app before using it in DVDSP.
24fps content has 20″ less frames that 29.97 so that content will stream faster or you can give it a 20% better quality settings during compression. (less frames = smaller file size, thereby faster compression and streaming. )
gary adcock
Studio37
HD & Film Consultation
Post and Production WorkflowsCheck out
https://www.aja.com/kiprotour/Inside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php -
Thank you both so much. I’m starting to see the light at the end of the tunnel!
To Dave & Gary…
(First to Gary) I have an iMac purchased in late 2007 so its fairly current. ProRes is always mentioned with HD projects and I was really just curious if it would help with SD projects (like the ones I shoot using my DVX100B). Graphics and Color Correction are fairly common in my projects but not used extensively. I’ve started to get hired to shoot a lot of green screen work though so I’m trying to maximize the tools I have at my fingertips for the best quality output.
(Now to Dave) I think I understand it all now except I’m stuck on two things you metnioned…
1.) “You’ll note that DV video contains 29.97 frames, containing TWO INTERLACED FIELDS, per second.”
Per second? Really? That confuses me a bit…Isn’t it per frame?
2.) Secondly, I spoke of using 24p (normal) and you mentioned in your last post…“If you don’t remove the pulldown, you’ll have problems later. “
Don’t get me wrong, I’m gonna start shooting 24pAdvanced and removing pulldown upon capture and edit in a 23.98 timeline with all sequence settings set to progressive (right?)…but everything I’ve shot the last 2 years was 24p (normal) and edited on a 29.97 timeline and outputted many DVDs and flash videos for the web at 29.97 and they “appear” to be okay…so if you don’t mind me asking…what “problems” were you referring to that might I run into later?
You guys are so great! This forum is great! I have a few more questions posted on the DVX website (some similar questions) as they are more DVX and Final Cut Pro specific. If anyone wants to take a crack at those its below (hope that’s allowed)…otherwise, thank you all very much for your help!
https://www.dvxuser.com/V6/showthread.php?t=174758
Thanks!
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