A1: Progressive Vs. Interlaced dilemma

[Gabriele Sartori]

Guys, please help me here. I love this camera (A1) but it has too many modes and I can’t take a decision. Should I use it in 60i or 30F?

I’m a sucker for resolution and on my Sony 60” 1080P TV the 60i seem sharper to me. All the tests on the internet would prove that. On the other hand I get better results downconverting 30F to regular DVD than 60i (may be my technique but the interlaced fields are not blended as well as I wish).
True is that DVDs will eventually go away in my home since I’ll move to blue ray and I could probably keep everything in 60i for ever. The 30F is damn cool though and much better than my old 720P from JVC (HD1) I don’t mean the obviously better resolution and colors but also in terms of progressive artifacts the Canon is MUCH BETTER. They are almost absent.

With the JVC though I was an happy camper with 30P and since I didn’t have other choices I wasn’t making my life too complicated, now I have a dilemma every time I use the camera : 30F or 60i ?

I’m bugged by the loss of resolution in 30F (that may be is just in my head, please convince me otherwise)

I’m bugged by the interlace artifacts when I scale down to progressive DVD SD when in 60i (may be you do a better job then me setting your SW, I use Premier 1.5 btw)

Give me a suggestion so I stop with this and go for one mode only. Now I’ve 50% of my tapes in 30F and 50% in 60i can’t go on like this :-)

Thanks a lot

Gabriele

[Bill Pryor]

I like the look of 30F better. No interlace artifacts. The loss of resolution is insignificant for me.

[Tom Roper]

There's no resolution loss in the horizontal, and only 10.6% loss in the vertical for 24F.

I prefer 60i for the smoother motion handling and reality look.

http://dvinfo.net/conf/showpost.php?...2&postcount=17

[Dave Perry]

I like 30f over 60i and 24f. No resolution loss in 30f and no interlacing issues on down conversion.

[Michael Mann]

I prefer the full frame mode (25F, since I live in PAL land).

Nevertheless interelace gives you one option that might be interesting and that I have used quite a lot in the past:
You can render films with DOUBLE FRAME RATE (60p in your case) which gives you unseen motion definition. I use Vegas for this (field interpolation) and the results look very convincing.

[Richard Hunter]

Originally Posted by Gabriele Sartori

I’m bugged by the interlace artifacts when I scale down to progressive DVD SD when in 60i (may be you do a better job then me setting your SW, I use Premier 1.5 btw)

Give me a suggestion so I stop with this and go for one mode only. Now I’ve 50% of my tapes in 30F and 50% in 60i can’t go on like this :-)

Hi Gabriele. If you shoot 60i, why not make 60i DVDs? This would help to avoid interlace artifacts because most TV monitors can handle interlaced video very well.

Richard

[Richard Hunter]

Originally Posted by Michael Mann

You can render films with DOUBLE FRAME RATE (60p in your case) which gives you unseen motion definition. I use Vegas for this (field interpolation) and the results look very convincing.

Hi Michael. Can you explain what you mean by "unseen motion definition". Sounds very interesting but I haven't come across this before.

Also, how do you use your final 50p output? Is it only for viewing on a computer or is there some DVD player that supports this?

Richard

[Fergus Anderson]

Originally Posted by Michael Mann

I prefer the full frame mode (25F, since I live in PAL land).

Nevertheless interelace gives you one option that might be interesting and that I have used quite a lot in the past:
You can render films with DOUBLE FRAME RATE (60p in your case) which gives you unseen motion definition. I use Vegas for this (field interpolation) and the results look very convincing.

Hi Michael I would also be interested in this
Are you Changing the project properties in Vegas to 50fps (double PAL) and then rendering in 50p?

[Michael Mann]

Fergus and Richard, I change Vegas project properties to 50 fps (progressive), although this is not necessary. I simply render my 1080 50i projects with a 720 50p template (interpolating fields) and get 50 fps clips. These clips are only for my computer.

Sure, this is not native 50 fps - due to the interpolation of the fields there are subtle artifacts. But the motion definition (when panning, for example) is 50 fps and it looks stunning compared to the more "stuttering" 25 fps film look that we are so used to. 60 fps is even more stunning.

[Tom Roper]

Originally Posted by Dave Perry

I like 30f over 60i and 24f. No resolution loss in 30f and no interlacing issues on down conversion.

I think there will be the same resolution loss in the vertical for 30F as there is for 24F. I'm going to do the resolution test for 30F using the IMATEST MTF50 software and post the result later today.

[Tom Roper]

Originally Posted by Michael Mann

Nevertheless interelace gives you one option that might be interesting and that I have used quite a lot in the past:
You can render films with DOUBLE FRAME RATE (60p in your case) which gives you unseen motion definition. I use Vegas for this (field interpolation) and the results look very convincing.

I think that would be spectacular for motion handling. My JVC GR-HD1 had a 480p60 mode that would give a clue, lower resolution yes..., but incredible reality.

[Michael Mann]

Originally Posted by Tom Roper

I think that would be spectacular for motion handling. My JVC GR-HD1 had a 480p60 mode that would give a clue, lower resolution yes..., but incredible reality.

Yes!

I once watched a SHOWSCAN ride film (70 mm at 60 fps) in Las Vegas. Very impressive ... not the plot, but in terms of reality of motion. (I guess the technical term is "motion definition", or is it "motion resolution"?)

[Fergus Anderson]

Originally Posted by Michael Mann

Fergus and Richard, I change Vegas project properties to 50 fps (progressive), although this is not necessary. I simply render my 1080 50i projects with a 720 50p template (interpolating fields) and get 50 fps clips. These clips are only for my computer.

Sure, this is not native 50 fps - due to the interpolation of the fields there are subtle artifacts. But the motion definition (when panning, for example) is 50 fps and it looks stunning compared to the more "stuttering" 25 fps film look that we are so used to. 60 fps is even more stunning.

Michael I have tried this and it looks great - my only problem is that my PC struggles with 50p WMV files - I can only really go up to 720p. Does this method mean that its bob deinterlacing - ie loosing half the resoltion? If so is it necessary to go to 1080p? What format are you rendering to?

Cheers

[Michael Mann]

Fergus, try to modify the default MainConcept-mpeg-template (HDV 720-25p) that comes with Vegas. Set frame rate to 50 fps (progressive) and increase the bitrate from 18.3 to about 40 Mbit/s.

For even better renders I modify the AVI CineForm template (HDV 720-25p Intermediate) that comes with Vegas.

I am sure the Vegas deinterlacing procedure is not BOB but something much more "intelligent", since the render - although it is "only" 720 - looses almost no definition/resolution compared to the native 1080.

By the way: I always use the Classic Media Player to play back the rendered 50p files.

[Tom Roper]

Originally Posted by Dave Perry

I like 30f over 60i and 24f. No resolution loss in 30f and no interlacing issues on down conversion.

30F does result in a small drop in the vertical resolution over 60i, just like 24F, about 10-12%.

http://dvinfo.net/conf/showpost.php?...0&postcount=39