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Discussion Starter · #1 ·
Now that I am finally installed I need to deal with some niggling problems I have been ignoring. One is I often get some noticeable faint rolling pattern of wide horizontal bars that typically move bottom to top. Today for a while it was quite prominent in the green tube. But I have seen it sometimes in the other tubes. Sort of like the way Igor's hump moved in Young Frankenstein.


The two things I don't like about my G70 that occasionally makes me miss my 1271 is the clarity sometimes permits me to see scanlines. And the second is this intermittent rolling thing. Its rarely completely gone. But fortunately its often barely noticeable. Both make me aware I am watching a video projector. Something I could completely forget with my 1271.


I have tried swapping around BNC cables. I should note that I use a powered conversion box to take me from VGA to RGBHV as opposed to unpowered adaptor cables. There is a gray little cigarette pack sized box with a dial to adjust the image to the left or right.
 

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Quote:
Originally Posted by atomiccow /forum/post/18158731


One is I often get some noticeable faint rolling pattern of wide horizontal bars that typically move bottom to top.


I should note that I use a powered conversion box to take me from VGA to RGBHV as opposed to unpowered adaptor cables.

Try to connect all equipments to same ac-line using extension cable. If that doesn't help try without that conversion box, sometimes cable drivers and gamma boxes cause those rolling horizontal bars.


What resolution you use, when you see scanlines?
 

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Discussion Starter · #3 ·
Thanks. Glad you asked. I am running 1080i off my computer using power strip. Probably at 60 hz. And I have been considering I might have to find a more compatible setting. I would say all the equipment is running off the same AC line running from a couple multitap power strips. I would not have thought that running everything out of the same plug would be a virtue. I thought you might tell me to plug the projector into its own line.


Ooops. Now that I think of it today I plugged the projector into a different outlet up in the ceiling. But it is all part of essentially the same system. The theater is in my garage. A side room in the garage. I would not be surprised if the conversion box was an issue and would even like to buy unpowered cables.. The mitigating counter to that is I used the same box since 2001 and it never caused rolling on my 1271.
 

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Quote:
Originally Posted by atomiccow /forum/post/18158845


Thanks. Glad you asked. I am running 1080i off my computer using power strip. Probably at 60 hz. And I have been considering I might have to find a more compatible setting.

For film based 24p material test 1080i96Hz settings to get smoother pannings and less distracting scanlines.


You can also adjust spot shape to vertical oval shape using cpc magnets and dynamic astig to mask scanlines. Vertical oval shape also makes horizontal resolution bit sharper.

 

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Discussion Starter · #6 ·
Thank you very much for the numbers. I will try them out. For me with Powerstrip its pick one and hope for the best. Fortunately or not I haven't fully sharpened the projy. And its good to know I might have an option minimize video qualities with focus. I haven't properly set up the focus yet anyway.
 

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Discussion Starter · #7 ·
When I can or have to I like to answer my own questions in hopes someone will find the thread and it helps them.


So in my case the faint rolling was caused by the previous owner having the gain on all the tubes at 220 and over. I dropped them back to 180 and the picture looks fine with no more rolling. I might have to pop the green slightly. Its just the minutest tinge red.
 
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