CRT Filter
CRT filter that puts a photo or video on an old TV screen: curved glass, scanlines and a real phosphor mask, from Trinitron stripes to shadow-mask dots. Free.
What is a CRT filter?
A CRT filter makes your picture look like it's on a cathode ray tube, the screen in an old TV or arcade monitor. The tube draws with electron beams that sweep across line by line (those are the scan lines) and light up phosphors on the back of the glass. In a color tube, a mask sits in front of the phosphors so each of the three beams only hits its own color.
RCA's shadow mask is a steel sheet full of tiny holes over dot triads. Sony's Trinitron, first sold in 1968, used an aperture grille of thin vertical wires over stripes instead, and a slot mask has short rectangular openings.
How do you make a photo look like an old TV screen?
Choose a Mask: Aperture grille, Slot mask, Shadow mask, or None if you just want scanlines. Mask size is the width of one red, green and blue triad, and Mask strength is how much the pattern shows.
Curvature bulges the glass, and Scanlines darkens the gaps between the lines. Under Tube you'll find Convergence, which shifts the red and blue beams away from green, plus Vignette for darker edges, Flicker for a brightness wobble and Corner radius to round off the screen.
Arcade is the default, and Trinitron, Home TV, Monitor and Flat scanlines set up other kinds of screen. If you're after the signal instead of the screen, VHS Effect wears the picture down like old tape and Bad TV Effect makes it roll.
Settings for an arcade cabinet, a Trinitron, a living-room TV and scanlined pixel art
For an arcade cabinet, keep the Arcade default, but raise Mask size to 6 if you're exporting video. A Trinitron wants low Curvature (0.06), Mask size 3 and lighter Scanlines, which gives a sharper, flatter screen. For a living-room TV, Home TV switches to a shadow mask with more curve, beams out of line (Convergence 1.4) and heavier flicker.
For scanlines over pixel art, Flat scanlines turns off the mask, the curve and the corners. The lines repeat every 4 pixels of a 1080p frame, which works out to 270 lines top to bottom at any size. Art that's 270 or 135 pixels tall gets one or two lines per row. You can make art at those sizes with the pixelating tools in the Pixel Art & Mosaic Effects hub, using a block size of 4 or 8.
How the phosphor mask stays sharp
Every phosphor stripe gets at least one whole pixel, so a triad never gets narrower than three. Go any finer and the red, green and blue would blur into a single color. On a landscape 720p video you hit that floor at Mask size 4.5, so anything smaller looks the same there.
Sizes are measured against a 1080p frame and then scaled to your file, so the mask and scanlines keep the same proportions at any resolution. Outside the rounded corners the frame is black, like the rim of the tube. The Seed fixes the flicker, so your export flickers exactly the way the preview did.
Why does the mask turn to rainbow bands or vanish in my video?
There are two things that wreck a fine mask. MP4 and WebM store color at half resolution, so stripes of red, green and blue that are one pixel wide merge into gray. And any scaling, whether it's a GIF's 960-pixel cap or a player shrinking the frame, makes the stripes beat against the new pixel grid and turn into moiré.
For video, set Mask size to 6 or higher, or switch Mask to None and keep just the Scanlines. When you check stills, look at them at 100 percent zoom.
Saving a CRT picture
Save stills as PNG at full size. JPG smears single-pixel stripes into a muddy tint. The corners outside the rounded screen are black, so you won't get a transparent frame.
A strong mask plus dark scanlines dims things a lot: at full Mask strength and Scanlines 1, average brightness drops to about half. So either start with a bright source or keep both below 0.5.