Archived from groups: alt.tv.tech.hdtv (
More info?)
"GREG BUGGY" <gbuggy@verizon.net> wrote in message
news:_Z0le.379$Li3.188@trndny05...
>I have the Dish Network. They say it's digital so is the same as DTV that I
>can get OTA?
Nope... most likely very different - but you just can't tell up front - you
gotta look and see
Digital doesn't mean anything on sat or cable wise except that the channels
are compressed and sent digitally, not in analog NTSC format like OTA and
cable analog channels
The cable/sat "digital" channels can be either as good as the best analog or
worse than the worst analog - all depending on the quality of the
digitization and the compression ratio used.
For OTA digital TV, there are more standards - for instance the signal must
be transmitted either in 480P (SD) or 720P (HD) or 1080i (HD)... but that
still doesn't mean that the original content was digitized well or that the
compression ratio isn't set too high to allow multiple sub-channels to share
the same bits while a channel looks terrible.
For instance, here in Richmond, the local Fox affiliate, owned by HD-hating
Sinclair Group until recently took an off-the-air analog reception of its
own ghost and noise laden UHF channel, digitized it, (ghosts, low-res and
noise included) and retransmit as a 480P "DTV" channel that looked like
absolute garbage. And there are some "digital" cable channels that look
worse than pixelated Chinese VCD pirated movies - while others appear near
DVD quality. The local NBC affiliate uses its 19.6Mbits/sec digital signal
to send three subchannels, a 1080i 16:9 "HD" (that is probably
overcompressed), a 480P SD simulcast of the HD in 4:3 format, and a bit
starved SD 4:3 live local weather radar channel (often the best one to
watch).