Quantcast Very odd VHS tape recording mystery, red/blue color bands on screen - digitalFAQ Forum
  #1  
09-04-2011, 11:06 AM
jimvhs jimvhs is offline
Free Member
 
Join Date: Aug 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
I have a VHS tape that exhibits very poor tracking along with a myriad of red/blue color bands flipping around the screen. It appears like this on any deck I try to use.

The really odd thing I noticed is when I view the tape using the Jog/Shuttle on my AG1980. I was trying to see if the "bad tracking" and colors were recorded on the tape when the thing was copied. When I pause the tape and then fast forward slightly, the screen splits into a several horizontal bars. Each bar alternates with the footage that was at first poorly visible and what appears to be a basketball game recorded off a TV broadcast.

So it would appear that the game was recorded at first (confirmed at the "end" of the home video recording because the game comes back on with no tracking issues or color bars) and then home videos recorded over the game.

My question is, I guess, a forensic one: what circumstances must exist for something like this to happen?
Crappy VCR recording? (obviously) Basketball game recorded with 4-head machine and later home videos recorded over on same tape with 2-head machine?

Not sure if this is fixable, but I am more interested in what caused it. I have been through thousands of tapes and never encountered something like this before.

edit: forgot to note that the original recording of the basketball game was done in EP/SLP and the later home movies recorded OVER the game were done in SP mode.

Last edited by jimvhs; 09-04-2011 at 11:12 AM. Reason: more info
Reply With Quote
Someday, 12:01 PM
admin's Avatar
Ads / Sponsors
 
Join Date: ∞
Posts: 42
Thanks: ∞
Thanked 42 Times in 42 Posts
  #2  
09-04-2011, 11:17 AM
admin's Avatar
admin admin is offline
Site Staff | Web Development
 
Join Date: Jul 2003
Posts: 4,350
Thanks: 128
Thanked 546 Times in 427 Posts
I'd like to see a sample clip (or even still images) -- attach to forum, please -- before being sure of my answer.
My initial instinct, however, is simple lack of a flying erase head during recording.

- Did this site help you? Then upgrade to Premium Member and show your support!
- Also: Like Us on Facebook for special DVD/Blu-ray news and deals!
Reply With Quote
  #3  
09-04-2011, 11:47 AM
jimvhs jimvhs is offline
Free Member
 
Join Date: Aug 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Four still images.
One is how it looks during playback
Two are what it looks like in slo-scan fwd or rev, half the frame is the home video and the bottom half is what was previously recorded (sports TV)
One is scanning quickly forward, the screen breaks into several bars with every other bar either the home movie, or the previously recorded sports show.


Attached Images
File Type: jpg playback.jpg (57.6 KB, 22 downloads)
File Type: jpg scan-ffwd.jpg (76.9 KB, 16 downloads)
File Type: jpg slo-scan1.jpg (59.4 KB, 15 downloads)
File Type: jpg slo-scan2.jpg (56.1 KB, 15 downloads)
Reply With Quote
  #4  
09-04-2011, 01:07 PM
jimvhs jimvhs is offline
Free Member
 
Join Date: Aug 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
attached (previous pics were just snaps of monitor...)


Attached Files
File Type: mp4 vhstest.mp4 (2.60 MB, 9 downloads)
Reply With Quote
  #5  
09-05-2011, 12:19 AM
admin's Avatar
admin admin is offline
Site Staff | Web Development
 
Join Date: Jul 2003
Posts: 4,350
Thanks: 128
Thanked 546 Times in 427 Posts
Ouch!

That looks to be a combination of inferior grade tape, malfunctioning/inferior recording VCR/camera heads, and lack of flying erase head.

What brand/make of tape is this? Give not just brand, but any sub-branding.
(For example, not just JVC, but JVC EHG. Doubting this is a JVC tape, of course -- those were good tapes!)

This is good example of why consumer grade VHS tapes should never have been re-used.
Of course, nobody ever listened to that -- not even me. (Stupid, stupid, stupid! Oh well, live and learn.)

I've seen this before, though often in much worse condition. You're actually lucky that it's still this good.

I'd have to refer to my trusty VCR tech manual ("a VCR Bible", if ever there was one), but based from an educated guess, I'd say part of the "still there" old signal is a situation created by different recording modes, combined with narrowed recording heads, then played back on a deck with wider playback heads. So part of the old signal still exists.

The red/blue noise is purely chroma errors caused by lack of flying erase head. It's bleed-through from prior recordings. Remember VHS is a color-under analog signal recording.

The other tape quality issues are likely from self-destruction of the tape on second use. Re-recording wasn't part of the planned use of consumer VHS tapes. It's not much different than writing on paper, erasing it, writing again, erasing again. You'll notice the paper's quality is all shot. The cheaper the paper, the quicker it goes. For example, construction paper or news print, vs thick laser/inkjet stock. I remember writing on "Big Chief" tablets in elementary school. One mistake, and that eraser ate a hole through the paper.


___

Off-topic:

I did a quick Google search for "Big Chief tablet", and came across this blog: http://www.ddranchwear.com/blog/2010...chief-tablets/
This quote gave me a chuckle:

Quote:
I loved Big Chief tablets. Well…truth is, I loved them except when I had to make a correction and my eraser eroded the paper and it got all nappy.
Exactly.

Apparently they quit making them more than a decade ago. We're all sad for nostalgic reasons, but the paper was truly crappy.
Not much different from many VHS tapes of the 1990s. (1970s-80s tapes were generally much better made.)

- Did this site help you? Then upgrade to Premium Member and show your support!
- Also: Like Us on Facebook for special DVD/Blu-ray news and deals!
Reply With Quote
  #6  
09-05-2011, 07:40 AM
jimvhs jimvhs is offline
Free Member
 
Join Date: Aug 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
It's SCOTCH. No sub branding that I can see. There is no box and no other marking on the tape case.

The home video is from 1985, but that was most likely dubbed from another tape to this one at some point.

Thanks for the insights into the causes of this mess.
Reply With Quote
  #7  
09-17-2011, 11:51 PM
lordsmurf's Avatar
lordsmurf lordsmurf is offline
Site Staff | Video
 
Join Date: Dec 2002
Posts: 5,657
Thanks: 532
Thanked 808 Times in 727 Posts
Quote:
Originally Posted by jimvhs View Post
It's SCOTCH. No sub branding that I can see. There is no box and no other marking on the tape case..
Eh, this tape could go either way, depending on exact model and age. I have some great Scotch tapes, and some awful ones.

Quote:
The home video is from 1985,
Equipment from this era likely accounts for a good bit of the degradation alone.

Quote:
but that was most likely dubbed from another tape to this one at some point
This definitely leads to dismal video quality. Many of us did not realize it back in those days, as many of us were still just general consumers. As the 80s turned into the 90s, many of us realized what mistakes we were making. As the 90s turned into the 2000s, those earlier takes got even uglier when viewed on gorgeous high resolution digital displays. Oops.

Glad to see it's all been figured out.

If you have further questions, just post them (make new threads/posts), and we'll be glad to help.

- Did my advice help you? Then become a Premium Member and support this site.
- Find television shows, cartoons, DVDs and Blu-ray releases at the TVPast forums.
Reply With Quote
Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
Video capture w/ horrible color noise "bands" lzrplayr Capture, Record, Transfer 20 08-09-2015 05:27 PM
Screen protectors for matte screen LCD on Macbook pro laptop? Sossity Computers 1 12-09-2010 07:01 PM
DV color space harmful to analog color quality? Verify? DeXeSs Capture, Record, Transfer 6 06-27-2010 01:48 AM

Thread Tools



 
All times are GMT -5. The time now is 07:48 PM  —  vBulletin Copyright Jelsoft Enterprises Ltd