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Originally Posted by LLKJR:

Just finished watching "Rails to Roanoke". The N&W is my second favorite RR.  611 and 1218 took center stage.

 

Larry

Unfortunately the late Marc Balkin of Mark I video apparently did not understand the 7.5 IRE pedestal used with NTSC television standard used in North America. 

 

On a computer, (and on professional grade video cameras) a digital zero is Black. This maps to 0 IRE on NTSC television which is "blacker than black".  In order to display black correctly on your NTSC TV the digital zero must be raised to a digital 16 which maps to 7.5 IRE on your TV which is "legal" Black.

 

What does all this doubletalk mean?

 

Mark I Videos all suffer from what is called "black crush", meaning that the darker shades and true black are all below the visual limit on NTSC TV.

 

The videos are too dark and all detail is lost on the low end.

 

It's a shame because he had quite a collection of outstanding archival footage of steam and diesel from the 30s thru the 70s.

Originally Posted by Nick Chillianis:


 

Mark I Videos all suffer from what is called "black crush", meaning that the darker shades and true black are all below the visual limit on NTSC TV.

 

The videos are too dark and all detail is lost on the low end.

 

It's a shame because he had quite a collection of outstanding archival footage of steam and diesel from the 30s thru the 70s.

So you would need to get the raw footage and reprocess it with a digital 16 offset to correct the error, I assume.  And no doubt all this footage is long gone, and would be costly to redo.

Originally Posted by rrman:
Originally Posted by Nick Chillianis:


 

Mark I Videos all suffer from what is called "black crush", meaning that the darker shades and true black are all below the visual limit on NTSC TV.

 

The videos are too dark and all detail is lost on the low end.

 

It's a shame because he had quite a collection of outstanding archival footage of steam and diesel from the 30s thru the 70s.

So you would need to get the raw footage and reprocess it with a digital 16 offset to correct the error, I assume.  And no doubt all this footage is long gone, and would be costly to redo.

 

The raw tapes may still exist (and considering it was mainly shot on Beta, you would have better clarity than what VHS could do--presuming the masters have held up), but what market would purchase a re-edit?  That's not a cost-effective procedure.

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