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scharfis_brain · 5th August 2003, 10:23

@Fred: those values for shifting chroma, i've only got by testing, "what looks best". After a while I found out, that every generation of VHS-copy introduces a new vertical shift by 2 lines.
so, a copy from VHS->VHS has already chroma shifted by 4 lines.
The same with horiz. shift. You have to try to relocate the chroma using your eyes, but this isn't very easy, because of the bleeding....

@SeeMoreDigital: Not, its NOT the Composite-Connection. Its the VHS, that is the reason for the bleeding chroma.
VHS strores LUMA with about 2,5MHz bandwidth, and the CHROMA is stored with about 0,6 MHz, so there are about
240 lines of LUMA you can store
and
60 lines of CHROMA. I hope, you'll see it now, why chroma is bleeding horizontally on VHS...

@all: I am talking about PAL-VHS. I don't know wheather NTSC-VHS will introduce the vertical shift, too since I am already able to deal with PAL60 and not with real NTSC. With using PAL60 (on NTSC-Tapes) the vertical shift is also there, like when using true PAL-VHS. All other things should be the same.

EDIT: please take a look at this: http://www.gthelectronics.com/featurec.htm
I think they described it very well... (color bleed and color droop)

5th August 2003, 10:23	#12 \| Link
scharfis_brain brainless Join Date: Mar 2003 Location: Germany Posts: 3,653	@Fred: those values for shifting chroma, i've only got by testing, "what looks best". After a while I found out, that every generation of VHS-copy introduces a new vertical shift by 2 lines. so, a copy from VHS->VHS has already chroma shifted by 4 lines. The same with horiz. shift. You have to try to relocate the chroma using your eyes, but this isn't very easy, because of the bleeding.... @SeeMoreDigital: Not, its NOT the Composite-Connection. Its the VHS, that is the reason for the bleeding chroma. VHS strores LUMA with about 2,5MHz bandwidth, and the CHROMA is stored with about 0,6 MHz, so there are about 240 lines of LUMA you can store and 60 lines of CHROMA. I hope, you'll see it now, why chroma is bleeding horizontally on VHS... @all: I am talking about PAL-VHS. I don't know wheather NTSC-VHS will introduce the vertical shift, too since I am already able to deal with PAL60 and not with real NTSC. With using PAL60 (on NTSC-Tapes) the vertical shift is also there, like when using true PAL-VHS. All other things should be the same. EDIT: please take a look at this: http://www.gthelectronics.com/featurec.htm I think they described it very well... (color bleed and color droop) Last edited by scharfis_brain; 5th August 2003 at 10:31.