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View Full Version : TV static "ripples" effect?


dougoftheabaci
04-21-2008, 04:06 AM
I'm working on a project, bit of client work. Anyway I'm creating a poster that features an old, retro TV. Unfortunately we we couldn't find a stock image that was perfect and we didn't have the ability to photograph a TV we liked so I had to get the best stock image I could and go from there in Photoshop.

I'd gotten it perfect and I was showing it to the client and I had it zoomed out. Ever seen how you get this almost ripple effect in static? Here's an image of what I'm talking about:

http://www.dougstewartdesign.com/tests/static.jpg

It's only there when zoomed out. I know it has something to do with the way the screen renders the image and it's an optical illusion but the client nearly had a fit. I now have been charged to recreate that so it looks like that at ANY size, so he wants it a permanent part of the image.

I've tried drawing it by hand, I've tried looking for plugins, I can't seem to find anything that can duplicate the effect to where I'm satisfied.

Does anyone know a technique, plugin, bit of stock, anything at all that will help me get this effect?

kraal
04-21-2008, 02:07 PM
not as hard as you think in photoshop...... make a circle pattern a light and dark color.blur it and a noise filter over top....
do a web search for photoshop tv scan lines follow that simple tut.... makes a pattern and that pattern over grey then do the pinch filter ( or try other distort filters) and a noise layer over top and adjust contrast and color

dougoftheabaci
04-21-2008, 02:16 PM
I actually have a high-res image of TV static that I'm currently using. Much more realistic than any of the TV static tutorials I've found.

Sorry, maybe I should have listed out the processes I've tried. These include tracing and trying to draw it by hand.

Filter wise I used Half-Tone to create circles, blurry edges and all. Pinch doesn't creat an obvious visual effect and the bit issue is that it doesn't match a TV correctly. I've tried doing liquify but that, also doesn't seem to work right. Or at least I can't seem to make it look right. I'm getting desperate so I'll likely do it again.

I was kinda hoping someone knew of an automated way to do this.

Also, the ripples appear to have rainbow colour scheme to them. Anyone have any ideas how I might easily duplicate that without using a gradient for each circle?

kraal
04-21-2008, 02:41 PM
did you try a screen grap? and place that image?

dougoftheabaci
04-21-2008, 02:43 PM
Yeah, but it just doesn't look real enough for me. Plus, since it's pretty much a really low quality image scaled up large it will look horrible on a poster. I've tried various layer effects but none seem to work right.

kraal
04-21-2008, 02:57 PM
i did this real quick could you analyse this and tell me what you like or dont like????
http://www.artiscommunication.com/tv.jpg

dougoftheabaci
04-21-2008, 03:00 PM
That's pretty much how far I've gotten as well. I'm going to try doing a variety of things in a minute, first the circles, then the bubble effect, then warping and then seeing if I can use liquify to pull it all together.

I'll post back with my results and maybe you or someone else can help me figure out what else it needs.

dougoftheabaci
04-21-2008, 03:31 PM
OK, so I've had a moment to play with it and I've come up with a result that I'm actually happy with. It's not perfect, but it's a process that can be played with. Here's the result:

http://www.dougstewartdesign.com/tests/static2.jpg

Basically I used the Halftone pattern filter to create the rings, then I used Lens Correction to warp the the centre. Then I used transform Warp to get the really funky shape. I think there are too many rings, but still completely something that I can modify to get what I want.

The only real obstacle I have left is to convert it from back and white to coloured. I'm thinking maybe using it as a diffusion map but even if I did a gradient I'm not sure how that would turn out... Since I basically need to have each black line as a multi-coloured gradient and each one the same.

I don't suppose you know a technique that changes a single colour with a gradient? I doubt it, I'm likely going to just end up using replace colour or something... Thoughts?

[edit]
Forgot to mention this, the reason I'm not worried about the static is I'll just put this over the actual static I have so that I get the coloured effect on that static. with this I'm just interested in getting the colours.

tfritzsche
04-22-2008, 01:08 PM
Hi dougoftheabaci
Nice moire.
to get the colors I would offset the red and blue channels in opposite directions, just by a couple of pixels(depending on its size in image).
I dont know what your poster looks like or how big this is in the final print, but I would be careful with this effect, it may cause its own interference with the printers dot. Send a 100% croped section to the printer for a test print.

thomas

dougoftheabaci
04-22-2008, 01:15 PM
Hey Thomas, Thanks for the tip and advice. Luckily when my client saw the effect without colour he was happy with it. It also makes sense since the TV is supposed to be black and white anyway (old retro TV) which is something I hadn't actually thought of for some reason.

Thanks for the tip, I'm going to try it out anyway since it'll just be a nice trick to know anyway.

Thanks everyone who helped me out!

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