ComfyUI Node: Cathode Ray Effect

Cathode Ray Effect:

The CathodeRayEffect node is designed to simulate the nostalgic and visually distinct appearance of old cathode ray tube (CRT) displays. This effect is particularly useful for artists and designers looking to add a retro or vintage aesthetic to their digital images. By applying a combination of screen curvature, scanlines, glow, color bleeding, and noise, the node recreates the unique characteristics of CRT screens, such as the curvature of the display, the glow of phosphor, and the subtle imperfections that give these screens their charm. The node offers various presets and customization options, allowing you to tailor the effect to match different types of CRT displays, from arcade machines to consumer televisions and professional monitors. This flexibility makes it a powerful tool for enhancing the visual storytelling of your projects.

Cathode Ray Effect Input Parameters:

images

This parameter accepts the input image(s) that you want to apply the cathode ray effect to. The images should be in a format compatible with the node's processing capabilities.

preset

The preset parameter allows you to choose from predefined settings that mimic different types of CRT displays. Options include "static," "fluctuating," "degraded," and "custom." The default is "static," which applies a consistent effect, while "fluctuating" and "degraded" introduce variations over time. The "custom" option lets you define your own expression for time-based variation.

custom_expression

This parameter is used when the preset is set to "custom." It allows you to input a mathematical expression that defines how the effect varies over time. The default expression is sin(t/10) * 0.1 + 0.2, where t represents time.

screen_curvature

The screen_curvature parameter controls the amount of curvature applied to the image, simulating the rounded appearance of CRT screens. It ranges from 0.0 (no curvature) to 1.0 (maximum curvature), with a default value of 0.2.

scanline_intensity

This parameter adjusts the intensity of the scanlines, which are horizontal lines that mimic the scanning process of CRT displays. The intensity can be set between 0.0 (no scanlines) and 1.0 (maximum intensity), with a default of 0.3.

glow_amount

The glow_amount parameter determines the level of glow effect applied to the image, simulating the phosphor glow of CRT screens. It ranges from 0.0 (no glow) to 1.0 (maximum glow), with a default value of 0.2.

color_bleeding

This parameter controls the amount of color bleeding, which is the slight spreading of colors beyond their boundaries, characteristic of CRT displays. The range is from 0.0 (no bleeding) to 1.0 (maximum bleeding), with a default of 0.15.

noise_amount

The noise_amount parameter adds random noise to the image, simulating the static and imperfections often seen on CRT screens. It ranges from 0.0 (no noise) to 0.5 (maximum noise), with a default value of 0.05.

Cathode Ray Effect Output Parameters:

IMAGE

The output is the processed image(s) with the cathode ray effect applied. This output retains the original image format and dimensions, but with the added visual characteristics of a CRT display, such as curvature, scanlines, glow, color bleeding, and noise. The result is a stylized image that evokes the retro aesthetic of vintage screens.

Cathode Ray Effect Usage Tips:

• Experiment with different preset options to quickly achieve various CRT styles, such as arcade or consumer TV, without manually adjusting each parameter.
• Use the custom_expression parameter to create dynamic effects that change over time, adding an animated quality to your images.
• Adjust the screen_curvature and glow_amount parameters to enhance the retro feel, especially if you're aiming for a more pronounced CRT look.

Cathode Ray Effect Common Errors and Solutions:

Invalid custom expression

• Explanation: The custom expression provided is not valid or contains errors.
• Solution: Ensure that the expression is a valid mathematical formula and uses the correct syntax. Double-check for any typos or unsupported operations.

Image format not supported

• Explanation: The input image format is not compatible with the node's processing requirements.
• Solution: Convert your images to a supported format, such as JPEG or PNG, before applying the effect.

Parameter value out of range

• Explanation: One or more parameter values are outside the allowed range.
• Solution: Verify that all parameter values are within their specified minimum and maximum limits, and adjust them accordingly.