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Originally Posted by
jjvcary 
So...the tuner seems to be the culprit for the darker picture.
Yes, I don't think "tuner" is the accurate term to use, although it suffices well enough for me to know what you're talking about, especially since I've "seen it" directly ....
I'm not sure exactly what component/proccessing "step" is the culprit, My best guess is somewhere in the signal path after TS demux, and between the MPEG2 decoder used to decode source MPEG2 video stream and the MPEG2 encoder used to encode at 720x480i ... Besides resizing of 720p/1080i signals to 720x480, interlacing of 720p or 480p signals and ITU 709>>601 colorspace conversion for 720p or 1080i source signals as necessary, at present I can't think of anything else that needs to happen in there "between" the decoding of the original MPEG2 source video and the MPEG2 encoding for DVD, or why we're getting the significantly different black levels from video sourced from it's internal ATSC receiver ....
I've done much the same "process" which occurs(but as you might imagine with much better quality/results, especially as it involves programming orignally 24fps which can be IVTC'd or frames decimated to return it to 24fps via avisynth filters) via a PC using various software and HD broadcasts captured from ATSC receiver card for PC without ever experiening this issue nor ever having to, say, add a filter in AVisynth script to adjust luminance or "black levels". Of course, going through all that "on a PC" requires a lot more time and effort than using one of these DVD recorders ....
Nor have I ever had a problem with this involving the output of any ATSC receiver I have here or the DTV broadcasts from any local broadcaster, including ATSC receiver internal to a Sony HDTV which involves/allows "calibration" in a sense of it's "ATSC receiver input" via internal ATSC test pattern generator which is available via undocumented service menu feature ...
Anyway, Black levels from Magnavox H2080 or Phillips DVD3575H seem fine concerning the output and playback say, of "commerical" DVD's, or for that matter as encoded with the thing's MPEG2 encoder as sourced from it's analog s-video, composite, or Internal NTSC "tuner" ...
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I would be helpful if others might note the quality of their picture via the tuner and a purchased DVD.
I have one H2080MW8, and one Phillips 3575H, and had to return/exchange a H2080MW8 for the one I have now because there was a problem with the component video output with the first one (occasinal corruption involving rolling "lines") .. BTW, I also had to open up the 2nd H2080MW8 because the door wouldn't open/was stuck because the (sorry for the lack of proper terminology I don't feel like looking it "up" currently) thing that has the laser on it and moves back and forth to "read"(or write on) the disc was "stuck" in a posistion it should not have been which did not allow the door to open/close ...
Anyway ALL 3 of them have apparently signifcantly incorrect black levels(too dark) only via the signal path that "processes" the signals from the Internal ATSC "receiver"(including after those signals are encoded and written to DVD or HDD).
So, The problem seems to only involve video sourced from the internal ATSC receiver ... I don't have/use cable, but assume the same is true as well if you're using the internal QAM demod instead of 8VSB demod for OTA ATSC ...
Surely, sometimes these things can be "off" and video output a little different from different devices, which is fine and not a big deal when all we're dealing with is the output from different devices and can "adjust" within service menus or input specific black level controls in our displays user menu "picture adjustment" options --- But, what we are talking about here is something that is "wrong" that is not only getting written to DVD or HDD, but is also sigificantly "different" than the black levels occuring and being encoded involving analog source video from the SAME device's S-video or composite (analog) inputs, AND the black levels from MPEG2 streams that are encoded on DVD's which are actually encoded "properly"(such as commercial DVD's) and as they are played back on the same device ....
Which reminds me, I also tried the same "test" as Voyager6 described earlier either in this thread or one of the Philips 3575H threads involving using a external DTV receiver outputing 480i and hooked to the Mag's S-video input and comparing it to "recording" made from the same source signal with either the Manavox or philips internal ATSC receiver (exactly the same recording/scenes etc regarding the philips internal ATSC receiver vs. external DTV receiver via S-video on the mag - I tried it the "other way" around as well, using the Mag's internal ATSC receiver+external DTV receiver hooked up to the phillips via s-video) --- and pretty much experienced the same thing he did ... Most importantly, I saw what I'll call "correct"(more or less) black levels via the external DTV receiver and via s-video input on the recorder, which was "way too dark" via the Internal ATSC receiver(s) ....
One can only fix this by adjusting black level accordingly on their display when viewing video souced "through" these DVD recorders internal ATSC receivers, which will need to be adjusted *signifcantly differently* for video sourced through the Philips or Mag DVD Recroders internal ATSC/QAM receiver vs. anything else(including when playing back a "commercial" DVD, or video, including as stored on DVD or HDD sourced from these DVD recorders S-video/composite Inputs OR it's internal NTSC tuner), and INCLUDING if that video is encoded/written to disc and then decoded later on A DIFFERENT DVD player ...
While it's "manageable", in a sense by adjusting display's black level controls anytime you view signals processed through the signal paths involved for these DVD recorder's internal ATSC receivers(again including if you're playing DVD's created on those on OTHER DVD players), and "returning" that setting to the correct value for any other source video :
It's bad IMO, and I don't really understand how they could have produced this product without "noticing" this problem, or in other words can't quite imagine such a product could have gotten into the production phase without them noticing such a significant issue ....
BTW, I hope I'm not harping on this too much, hope this isn't a little "too wordy" as other than regarding this issue, and these recorders not supporting writing correct AR info "i.e. 16x9 "flag" when 16x9 material is encoded (which seems kind of silly as easy as it is to do on PC, such as when I use a software based MPEG2 encoder to encode MPEG2 video, such as HC encoder/etc), I'm quite impressed with what these things can do for relatively low cost ....
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This might help when making an appeal for a firmware upgrade to improve this. Thanks in advance
Hope some of this helps if you're in contact with them+appreciate your efforts if you are in contact with them ....
HOPEFULLY, a firmware upgrade or service menu adjustment of some sort is possible to fix this issue, but depending upon exatly what is going on, I'd guess it may be possible that it isn't possible and may require a hardware fix ...
Anything I can do? (Get the Philips machine instead?)
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