F mode Voodoo at DVinfo.net

Tony Tremble · January 30th, 2007, 11:04 AM

I've just spent the shooting in 25F and have gone through the rushes. Wow!!

Can anyone explain how the 25F works? I was expecting field doubling but much more seems to be going on perhaps some very smart deinterlacing.

How do the F modes retain so much resolution? I have searched the forum and not found an answer just a thread with a lot of speculation. Have the details been released? Is there a thread with the info?

So far the XH-A1 has exceeded my expectations. A wonderful camera.
Cheers
TT

Greg Boston · January 30th, 2007, 11:12 AM

Tony,

Can't you just appreciate the magic and let it go at that? The F modes have been 'speculated' about, but Canon, to the best of my knowledge, have not published any sort of white paper on how it's done exactly.

Go make some beautiful images and then come back and tell us how you created them. That's what this forum is all about.

Glad that you're happy with your new camera choice.

-gb-

Pete Bauer · January 30th, 2007, 11:31 AM

The best we know -- which isn't much -- is that Canon found a way to read all 1080 lines from an interlaced chip at the same instant (progressive read) and allegedly chose not to call it "p" to avoid confusion and criticism since it does use an interlaced CCD. The part that is unknown is why there is that slight rez drop in a static image as compared to 60i static image rez (insignificant to most of us at somewhere around 10%). If all 1080 lines are read at the same time and processed progressively from start to finish, you'd think 1080p and 1080i would have the same static resolution. Not sure we'll ever know the answer to that one.

Juan Diaz · January 30th, 2007, 12:08 PM

Go here and watch the Adam Wilt videos. These are from his DV Expo sessions.

http://www.pqhp.com/nbm/dvx06/

Somewhere in there he explains that he finally got an answer from Canon. Apparently in 24f mode they reclock the CCDs at 1/48 second and run the green CCD offset by one field from the red and blue and do a kind of pixel shift.

Details are still sketchy but in the end it doesn't really matter. Even with the resolution penalty, Canon's F mode still provides some of the sharpest pictures at this price range.

Bill Busby · January 30th, 2007, 07:56 PM

Quote:

Originally Posted by Juan Diaz

Go here and watch the Adam Wilt videos. These are from his DV Expo sessions.

http://www.pqhp.com/nbm/dvx06/

Being me having a "free day" today, I watched both of Adam Wilt's streams & there was no mention at all about this. Did I miss something?

In any event, it's always a treat to listen/watch him speak.

Bill

Juan Diaz · January 30th, 2007, 10:51 PM

It wasn't one of his planned topics. He just mentioned it offhand in answer to a question from the audience. So it would be easy to miss, but it's in there. But in any case, they are good to watch. The man definitely knows his stuff.

Chris Hurd · January 30th, 2007, 11:06 PM

Canon USA made some motions toward an explanation of Frame mode at a press event in New York back in November; our own Pete Bauer and Michael Wisniewski attended. There's at least a PowerPoint floating around for internal corporate use only, but so far no White Paper has been publicly issued on the subject, to the best of my knowledge.

Best way to describe it: Frame mode = Progressive Scan.

Chris Sinista · January 30th, 2007, 11:56 PM

I was just about to search for this exact topic, when I saw this thread at the very top of the new pots. Again just for the record.... thie forum rocks!!

Tony Tremble · January 31st, 2007, 02:14 AM

Quote:

Originally Posted by Chris Hurd

Best way to describe it: Frame mode = Progressive Scan.

It most certainly is! :)

Canon have done a wonderful job with this camera not only the F mode technowizardry but very good HDV compression too. It seems to avoid the artefacts that the Sony encoders produces.

Top Camera...

TT

ps Thanks those who answered the question. I'll check out the videos later. cheers

Bill Busby · January 31st, 2007, 02:35 AM

Quote:

Originally Posted by Chris Hurd

Best way to describe it: Frame mode = Progressive Scan.

Chris... just curious on your thoughts regarding the above quote & those NLE's that don't support Canons 24f mode. I'm only familiar with Avid (which doesn't support 24f yet... but then again, I'm still cutting on a defunct 3.0 version of Xpress DV... never made the jump to Xpress Pro, etc.), but it DOES support 24p.

My question simply is... if frame mode = progressive mode, then why do some NLE's, such as Avid not support it if it DOES support 24P?

ConfusedBilly :-\

Piotr Wozniacki · January 31st, 2007, 02:39 AM

Quote:

Originally Posted by Bill Busby

My question simply is... if frame mode = progressive mode, then why do some NLE's, such as Avid not support it if it DOES support 24P?

Bill, that an NLE lacks a template titled "Canon HDV 1080 24f mode" doesn't mean it doesn't support it; such a template ca easily be prepared by yourself, basing on the most similar settings (I did just that for Vegas).

Bill Busby · January 31st, 2007, 03:38 AM

Piotr, with Avid, there are only machine "templates", which are just the selectable decks &/or cameras & are simply text files written with certain formatting. I altered one for a friend once as an experiment (after examining how they were written), to help him with a problem he had with a Sony Dvcam deck that wouldn't record in DV mode in Avid & it actually worked. Like you said, I looked at a similar deck template (his had an "A" extension in the model #, but the template he was trying to use didn't).

Oh heck... it was so long ago I thought I was going to remember the particulars but now my brainerds have gone kaput :-\

Anyway... the point of my rambling is that I believe Avid doesn't support it maybe because it doesn't know how to interpret it during the capture process.

My version of XpressDV doesn't even support 24p... I was just curious about this since the day of finally upgrading to XpressPro etc. is near.

Bill

Piotr Wozniacki · January 31st, 2007, 04:19 AM

Bill, I was a little quick with my post; I din't take into account the intricacies of the 24p - the 25p format I'm using here is much more straightforward, sorry:)

Bill Busby · January 31st, 2007, 04:24 AM

Hey, no problem at all. As we say here in the US, no harm no foul :)

Regards,
Bill

Vincent Wong Yoon Wei · January 31st, 2007, 04:39 AM

One reason earlier NLE doesn't support Canon HDV 24F has a lot to do with the fact that Canon HDV 24F really records only 24 progressive frames into tape. Other camera does it using the pulldown b*llshit NTSC users have to deal with.

January 30th, 2007, 11:04 AM	#1
Tony Tremble Regular Crew Join Date: Oct 2006 Location: United Kingdom Posts: 451	F mode Voodoo I've just spent the shooting in 25F and have gone through the rushes. Wow!! Can anyone explain how the 25F works? I was expecting field doubling but much more seems to be going on perhaps some very smart deinterlacing. How do the F modes retain so much resolution? I have searched the forum and not found an answer just a thread with a lot of speculation. Have the details been released? Is there a thread with the info? So far the XH-A1 has exceeded my expectations. A wonderful camera. Cheers TT

January 30th, 2007, 11:31 AM	#3
Pete Bauer Wrangler Join Date: May 2003 Location: Eagle River, AK Posts: 4,100	The best we know -- which isn't much -- is that Canon found a way to read all 1080 lines from an interlaced chip at the same instant (progressive read) and allegedly chose not to call it "p" to avoid confusion and criticism since it does use an interlaced CCD. The part that is unknown is why there is that slight rez drop in a static image as compared to 60i static image rez (insignificant to most of us at somewhere around 10%). If all 1080 lines are read at the same time and processed progressively from start to finish, you'd think 1080p and 1080i would have the same static resolution. Not sure we'll ever know the answer to that one. __________________ Pete Bauer The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. Albert Einstein Trying to solve a DV mystery? You may find the answer behind the SEARCH function ... or be able to join a discussion already in progress!

January 30th, 2007, 11:06 PM	#7
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Canon USA made some motions toward an explanation of Frame mode at a press event in New York back in November; our own Pete Bauer and Michael Wisniewski attended. There's at least a PowerPoint floating around for internal corporate use only, but so far no White Paper has been publicly issued on the subject, to the best of my knowledge. Best way to describe it: Frame mode = Progressive Scan. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

January 30th, 2007, 11:12 AM	#2
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	Tony, Can't you just appreciate the magic and let it go at that? The F modes have been 'speculated' about, but Canon, to the best of my knowledge, have not published any sort of white paper on how it's done exactly. Go make some beautiful images and then come back and tell us how you created them. That's what this forum is all about. Glad that you're happy with your new camera choice. -gb-

January 30th, 2007, 12:08 PM	#4
Juan Diaz Regular Crew Join Date: Oct 2005 Location: Austin, TX Posts: 49	Go here and watch the Adam Wilt videos. These are from his DV Expo sessions. http://www.pqhp.com/nbm/dvx06/ Somewhere in there he explains that he finally got an answer from Canon. Apparently in 24f mode they reclock the CCDs at 1/48 second and run the green CCD offset by one field from the red and blue and do a kind of pixel shift. Details are still sketchy but in the end it doesn't really matter. Even with the resolution penalty, Canon's F mode still provides some of the sharpest pictures at this price range.

January 30th, 2007, 10:51 PM	#6
Juan Diaz Regular Crew Join Date: Oct 2005 Location: Austin, TX Posts: 49	It wasn't one of his planned topics. He just mentioned it offhand in answer to a question from the audience. So it would be easy to miss, but it's in there. But in any case, they are good to watch. The man definitely knows his stuff.

January 30th, 2007, 11:56 PM	#8
Chris Sinista Regular Crew Join Date: Jan 2007 Location: Pasadena CA Posts: 59	I was just about to search for this exact topic, when I saw this thread at the very top of the new pots. Again just for the record.... thie forum rocks!!

January 31st, 2007, 03:38 AM	#12
Bill Busby Major Player Join Date: Dec 2006 Location: Los Angeles, CA Posts: 959	Piotr, with Avid, there are only machine "templates", which are just the selectable decks &/or cameras & are simply text files written with certain formatting. I altered one for a friend once as an experiment (after examining how they were written), to help him with a problem he had with a Sony Dvcam deck that wouldn't record in DV mode in Avid & it actually worked. Like you said, I looked at a similar deck template (his had an "A" extension in the model #, but the template he was trying to use didn't). Oh heck... it was so long ago I thought I was going to remember the particulars but now my brainerds have gone kaput :-\ Anyway... the point of my rambling is that I believe Avid doesn't support it maybe because it doesn't know how to interpret it during the capture process. My version of XpressDV doesn't even support 24p... I was just curious about this since the day of finally upgrading to XpressPro etc. is near. Bill

January 31st, 2007, 04:19 AM	#13
Piotr Wozniacki Inner Circle Join Date: Aug 2006 Location: Poland Posts: 4,086	Bill, I was a little quick with my post; I din't take into account the intricacies of the 24p - the 25p format I'm using here is much more straightforward, sorry:)

January 31st, 2007, 04:24 AM	#14
Bill Busby Major Player Join Date: Dec 2006 Location: Los Angeles, CA Posts: 959	Hey, no problem at all. As we say here in the US, no harm no foul :) Regards, Bill

January 31st, 2007, 04:39 AM	#15
Vincent Wong Yoon Wei New Boot Join Date: Dec 2006 Location: Malaysia Posts: 5	One reason earlier NLE doesn't support Canon HDV 24F has a lot to do with the fact that Canon HDV 24F really records only 24 progressive frames into tape. Other camera does it using the pulldown b*llshit NTSC users have to deal with.