View Full Version : Blue hues


lnx64
12-13-2012, 09:40 PM
This is quite interesting. This pic is old but I still see this.. All new TV's, mid 90's and up, seem to show the sky in Super Mario Brothers purple. Older TV's show it blue.

The screen on the left isn't a TV, it's a Commodore 128 13" Teknika monitor (which is not overscanned - for computer use), and it shows the sky as blue, like all older TV's show the sky.

Both are tinted correctly, but why so drastically different in the color decoding?

http://img.photobucket.com/albums/v395/Evilweredragon/nescolor.jpg

And it's funny, even emulators show this differently too! Just do a google image search on the game, and see how the color appears different in almost every screenshot.

Jeffhs
12-14-2012, 12:04 AM
This is quite interesting. This pic is old but I still see this.. All new TV's, mid 90's and up, seem to show the sky in Super Mario Brothers purple. Older TV's show it blue.

They must have fixed that problem by the time flat panels replaced CRTs. My Insignia 19" FP (built in mid-2011) has very accurate and stable color. Also, my RCA CTC185 shows very accurate colors, even for being 13 years old; so does my 17-year-old Zenith Sentry 2.

BTW: The reason the sky color in that picture in your post looks purple, rather than blue, could very easily be because the photo is old, if it is a photograph printed from a negative; all photographs change color somewhat with age. I have color photos from the '50s-'60s on which the colors have faded and even shifted slightly.

lnx64
12-14-2012, 12:09 AM
BTW: The reason the sky color in that picture in your post looks purple, rather than blue, could very easily be because the photo is old, if it is a photograph printed from a negative; all photographs change color somewhat with age. I have color photos from the '50s-'60s on which the colors have faded and even shifted slightly.

Um, this was a digital photograph, and they really do look like this.

Besides, even if it was a film issue, that wouldn't explain why the Teknika monitor looked blue properly.

But anyway, this is old as in 2006-2007 old.

ischmidt
12-14-2012, 05:21 PM
Generally that's a matter of two things: the NTSC decoder chip/circuit in the TV and the tint control setting. Newer emulators provide an "NTSC filter" which adds dot crawl, simulates the effects of the differing chroma/luma bandwidth, and in some cases also provides the ability to select between various popular decoder IC types and fiddle with the tint control.

wa2ise
12-14-2012, 08:49 PM
Newer emulators provide an "NTSC filter" which adds dot crawl,

I worked years many years ago to get rid of such (RCA Labs), and someone wants to add it back? :scratch2: :yuck:

lnx64
12-14-2012, 10:17 PM
Yea, sadly some people want it back. I would prefer to rid of it.

On the NES, you can't really get rid of it, as the graphics chip itself outputs NTSC, no RGB pins (unless you mod it and solder in the arcade version of the mostly pin compatible chip). But I'm not going that far!