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Discussion Starter · #1 ·
Anybody know the best way to configure the de-interlacing/film mode options on an NTSC/ATSC HDTV Loewe Aconda to get the best playback of film-based DVDs from a 480i DVD player?


What do the different film mode options on Loewes do?
 

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I just turn "film mode" off. It will still pick up and engage 3-2 pulldown with 24fps material, but will not use motion compensation, which I've found makes movies look pretty strange.


Basically, what the "normal" and "super" film modes do is they create synthetic frames. Instead of taking the 24 frames (a, b, c...) and turning them into 30 (a,a,b,b,b,c,c,...) it actually takes each distinct frame, and instead of repeating, say b,b,b, then going to frame c, it'll display frame b, and then for the next two frames where other deinterlacers would just repeat b twice more, it actually tries to generate two frames that would represent the mathematical progression of the pixels from b to c. So what you get is b, b.1, b.2, c... with b.1 and b.2 representing two frames that actually were never shot, but generated by the deinterlacer by dividing the difference in pixel positions between frames b and c and averaging them twice into two new, synthesized frames. Ideally, the effect is that it looks as if it were actually shot at 60fps instead of 24. It is in fact effective in smoothing out motion from 24 fps sources. Unfortunately, it is not 100% consistent, so sometimes it is "more on" than others (depending on how motion-intensive the scene is). It also tends to soften the picture.


Given the complexity of the operation, I'd say the feature is remarkably advanced but for me ultimately produces an undesirable effect. For one thing, we as viewers are very much used to the characteristics of 24fps material unchanged. We associate the mild "flicker" and slightly jerkier motion with movies. Once you interpolate it into 60 frames per second, regardless of how well-done it is, it doesn't look much like a movie anymore.


As for the difference between "off," "normal," and "super," I would have to say that "off" generates no synthetic frames, normal generates some, presumably where most appropriate, and "super" generates them whenever possible. "Super" mode is both the most consistent and the softest. When set to "normal" you think you can see it going off and on from time to time, and when it's "off" it just looks normal. Which is why I keep it there.


By the way, regardless of how good the Loewe's internal doubler is reputed to be (and it is quite good, especially considering how old it is), it is still innately inferior to a progressive scan DVD player. Deinterlacing is always, always, always best performed in the digital domain, and the difference is very real. I strongly suggest a progressive scan DVD player or outboard processor like an HTPC.


Dan
 

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Discussion Starter · #3 ·
Thanks for the detailed reply, Dan.


This sounds rather different than the Cinemotion feature on the Sonys. If you turn the film-mode off on the Loewe, does the TV just perform simple field-based line-doubling on 480i? Or is it smart enough to read the cadence, and change it's de-interlacing routines automatically based on whether the content is 24fps film or field-based? If the video is 24fps film-based 480i is it smart enough to convert this to progressive 3:2 480p using reverse telecine? (You'd think this would be the "normal" mode for film, but I guess that's not the case.)


Are there any other de-interlacing/scaling options that need to be configured other than the film-mode?
 

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Thanks for the post Adu, and thanks Dan for the response, patient and detailed as always. I will need to experiment further, but so far I see little difference (in terms of shimmer or "judder") in any of the modes. Actually I just ordered a Denon 1600. If it's what it's cracked up to be, I should be able to get rid of the judder jitters. (I was tempted to go with an iScan but after the Aconda my wallet's still kind of bruised). I'll tell you, you guys know a lot more than my dealer does, so the help is great, especially for someone with the heart (or snobbishness?) of an audio/videophile and the brain of a technophobe. There, I got that off my chest.
 

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gentlemen,


adu - yeah, the loewe will in fact read the cadence and slip into reverse telecine weave mode for 24fps material, even with "film mode" set to "off." sony's "cinemotion" is merely its ad-friendly buzz word for the sony's ability to do that as well. sonys do not, however, have a motion interpolation feature similar to the loewe's. philips models do, though (as i understand it) and it is either undefeatable, terrible, or both.


of course, on all 30fps material, the loewe deinterlacer performs a typical "bob" method conversion. it does quite well at it, too. but the reigning champion remains dcdi, of course.


there are no other deinterlacing perameters to be set. however, you may want to mess with the noise reduction feature a bit to see if you like its effects. some people don't like any noise reduction at all, as it softens the picture a bit. and i'm usually one of those people, but the loewe's nr is so excellent that i keep it on at all times.



luminox-


i'm not sure what you're hoping the denon 1600 will do for your "judder," but i can assure you it will produce no smoother motion than the loewe on any of its "film mode" settings.


it will, on the other hand, give you far superior picture quality due to the high-grade dcdi deinterlacer in the machine, particularly on video material. though it probably won't do what you may be thinking it'll do, you will be very happy with the purchase.



dan
 

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Hmm, I'm a bit baffled. Dan, are you saying that motion artifacts, especially on vertical pan shots (what I've been calling "shimmer") are to be expected even using a dcdi de-interlacer? (This was the effect that a Brit reviewer complained of-- in an otherwise positive review-- and said that turning off "film mode" mostly eliminates).
 

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Discussion Starter · #7 ·
Dan,


FYI, this is the thread that got luminox and I onto this topic to begin with, FWIW. And the article which describes a "judder" problem which sounds similar to what luminox is seeing.


Unless there's some other motion-compensation feature hiding somewhere, it sounds as though luminox should just turn the film mode off when playing normal film-based DVDs from an interlaced player, and that ought to give 3:2 progressive playback. And maybe try some different NR settings.
 

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oh.... i see....


sounds like we've been equivocating on the term "judder." if luminox is indeed describing "jaggies" then the problem will be helped but not fully remedied by a progressive scan player.


however, the judder described in the article is something you will NOT see on the american aconda model. it's exclusively the result of the 100hz processing in the european model. motion problems are common with 100hz machines, even the best ones. american tvs do not have 100 hz processing because we already have a framerate that does not produce flicker.


i'm still a bit unclear as to the nature of the problem, but suffice to say that if something is bothering you about your dvd playback, luminox, it'll probably be remedied by using the denon 1600, which is an exceptionally fine player. deinterlacing in the set is just not a good way to do dvds. there's a very big difference when the deinterlacing is done in the dvd player in the digital domain.


if you want to try to describe the problem a bit more and the conditions where you notice it, i can try to look for it on my set as well and figure out what it is. good luck.



dan
 

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Dan, what I'm seeing happens on vertical pan shots, particularly those involving a highly "textured" scene. I saw it a lot on the movie Baraka which shows a lot of geologic formations. Also on Crouching Tiger. I take "jaggies" as something that occurs more on horizontal movement (which "film mode" seems to eliminate). The quality of what I'm talking about is more of a shimmer, or shaking-- an instability of image as the camera pans down, or up.
 

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Dan, I hooked up my new Denon 1600 and while it does not eliminate the problem, it almost does, to a satisfactory level I'd say. In other posts I've mentionned another problem which may be the set itself, which is the occurence of vertical bars or stripes apparent in low contrast. The Denon seems to have improved (but not eliminated) that as well, (or maybe it's the bettercables I'm now using) at least in component, not in S video. In S video (which I use for 4:3 interlaced) there is also a strange kind of shape-shifting going on, not distinct vertical bands but amorphous shapes kind of drifitng across the screen. You may have seen another thread which mentions the 30" having internal shielding problems, and I'm wondering if that is what my set has. No other Aconda owner seems to have this problem, or if they do, they are not saying. It definitely muddies the pictorial waters. Apparently a revised Aconda, the Basalt, has been released perhaps to address this very issue. An rather unconfidant sounding tech is coming to have a look. Otherwise I love the set.
 
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