Main > Monitor/Video Forum
How to use SCART for our hobby
Jollywest:
--- Quote from: apfelanni on October 23, 2011, 02:26:55 am ---24 k wont work . lowres only .
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Thanks for confirming :cheers:
Paradroid:
Another update on my search for the ultimate MAME/SCART TV…
I picked up a Loewe CT1170 television on Friday for AUD $10. It was covered in dust and cobwebs but I shined it up with a micro fibre cloth and thoroughly cleaned the insides with an air compressor. Man, this is probably the best unit I tried yet! Great colors, no dot crawl, geometry is very good (not perfect, but close), convergence is excellent and the image is incredibly solid. I also love the retro look of this TV! All black, no gimmicky design tricks.
Overall, I can safely say that any Loewe with an E3000 chassis should be excellent for retro gaming. I've tried a Contur, Profil, Profil Plus and now the CT1170. All have produced a true image without the artifacts that newer Loewe chassis and software revisions introduce. I just wish I'd kept the Calida with an E3000 chassis I found on the sidewalk six months ago... :( I turfed it because it didn't have a remote and I couldn't get an image with PowerStrip. Of course, Soft-15kHz came into my life after that and I'm sure that TV would have been killer. Oh well. The search continues...
Attached is a a snap of the CT1170 and joystick setup on the workbench.
MonMotha:
FWIW, there should NEVER be dot crawl on an RGB (or any format that has separate luminance and chroma information) signal. Dot crawl is caused by imperfect separation of the luma/chroma portions of composite video.
Paradroid:
--- Quote from: MonMotha on November 13, 2011, 04:22:27 pm ---Dot crawl is caused by imperfect separation of the luma/chroma portions of composite video.
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Would that suggest that the Loewe models that exhibit dot crawl are converting the RGB signal internally before their image processing stages?
MonMotha:
--- Quote from: Paradroid on November 13, 2011, 04:29:58 pm ---
--- Quote from: MonMotha on November 13, 2011, 04:22:27 pm ---Dot crawl is caused by imperfect separation of the luma/chroma portions of composite video.
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Would that suggest that the Loewe models that exhibit dot crawl are converting the RGB signal internally before their image processing stages?
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Could be. It may have something to do with the fact that RGB on SCART was actually intended to be used for OSD overlay over a conventional composite video signal - using it for an actual video source just always keeps it in "overlay mode" - so the TV may be internally generate a composite signal that it would send on to later circuitry. I'd think this would be pretty obvious, though; it would look more like composite than RGB.
It's also possible that you're seeing something similar that looks kinda like dot crawl but actually isn't. Some deinterlacers and upscalers can do weird things on sharp lines in computer graphics. Framerate conversions can also be problematic, depending on how they're done.
The wikipedia article on "Dot Crawl" has a picture that's pretty much a dead ringer for NTSC dot crawl, but I don't know if PAL dot crawl may look a bit different due to the phase alternation (again, not that it should be relevant on RGB). Is that what you're seeing on these things, or is it just more general "smudging"?