Tricky.
Many thanks! That will help me in my study quite a lot. Now I have to count
Same here.
He used a capture card.
Capture card, I see.
What's interesting about the first picture is that its colors are a bit
Yeah I know, but it doesn't explain why it happens in the first place. Sure,
If you look at them on a desktop it will be different.=O
Kinda new to the Framemeister - and this may have been covered, but what setting do I tweak to fix these uneven, clumped-together scanlines?
I thought we were retro all over the place here, no? Arrgh!
Don't forget to place a sticker on the console say it's not broken just
I somehow get an idea as to why composite video is so weak on the Genesis.
Regarding your last question, the issue with RF is the following. If RF
output is needed then the composite video signal coming out of the video
encoder goes into the RF encoder where it will be further processed. The
problem with RF is that the bounds on the transmitted RF video signal are
much tighter. There are safety margins, for example, to prevent sound
distortions by the video signal etc. And there are strict filter passband
characteristics to obey.
Basically, with RF, colors need to be clipped to make them broadcast-save so
to speak, i.e. the composite video signal needs to fit into a given range.
This fitting reduces the colors' saturation levels esp. for yellow, cyan,
red, and blue (they always look a bit dull on RF). A further problem within
this regard is that simply clipping the colors to make them broadcast-save
can change not only the colors' saturation levels but also their hues and
values, depending on the given broadcast signal limit, which would be pretty
bad because people are quite sensitive to changes in hue.
However, this was never a huge problem for standard TV transmission because
natural (non-synthetic) scenes don't have fully saturated colors. So all the
colors from natural scenes aren't that much of a problem regarding the
transmitter's limits. Hence, not much clipping needed. But if the colors go
outside of the save region then you will have to prepare for some
distortions. Now the bad news comes from the video consoles themselves
because they produce fully saturated colors like crazy. And it's here that
games start to look bad on video esp. when transmitted over RF.
These color issues needs to be addressed when doing graphics for video games
when being transmitted via composite video and/or RF. One could improve the
representation of the video game when obeying the limits of the transmission
system/channel, for example by using save colors right from the get-go.
The other issue with RF is that of filter characteristics. Before
transmitting the composite video signal via RF, its spectrum is transformed
into VSB (vestigial sideband (transmission)) with one part of one of its
sidebands suppressed (reducing channel bandwidth in the process). These
filtering characteristics needs to be as exact as possible because the TVs
filter's passband characteristic depends on it. Any mismatch here due to bad
filter design, weak roll-off, weak components (wear), too much delay (not
correctly compensated), etc. in the RF encoder and TV decoder (tuner) will
have a huge impact on the quality of the (to be) demodulated composite video
signal. This is where most of the issues with RF come from (not speaking of
any distortions of the RF signal while on its why to the TV). Hence, the RF
transmitter and the TV receiver need to match as close as possible, which is
very unlikely given all the tolerances and, well, cheap components resp.
simple filter designs. It's a trade-off. It's pretty expensive to build
analog devices to close tolerances.Today we can build much better converters, indeed. The question rises
whether Sega really went the cheapest route, had no other choice in some
departments, and/or have done some mistakes by design (regarding composite
video), i.e. could there be a better design at the same cost producing a
better video image on the screen?