Terms for the image side of engraving.

A raster image in which every pixel has only two possible values, usually black or white. In a prepared photo workflow, the black and white pixels form the final mark pattern. Resizing or dithering this file again can damage that pattern.

A display or image-processing technique that uses intermediate edge pixels to make shapes look smoother. Those gray edge pixels may need to be converted again in a one-bit workflow. Do not confuse a smooth screen preview with a preserved binary output.

The proportional relationship between an image's width and height, such as 4:5 or 1:1. Locking the aspect ratio prevents a face or object from being stretched when the physical engraving size changes.

An error-diffusion dither associated with a relatively light, crisp dot pattern because it passes only part of the quantization error onward. It can preserve an airy look but may lose information in very bright and very dark regions. Compare it with other methods at final size.

An ordered dithering method that compares pixels with a repeating threshold matrix. Its regular texture can suit graphic work and broad fills, but the pattern may be visible in a photograph.

A raster engraving motion in which the laser marks while the head travels in both directions. It can reduce job time, but mechanical alignment at a given speed must be correct or alternating rows may appear offset.

An image made from a rectangular grid of pixels. PNG, JPEG, and WebP files are common bitmap formats. A laser photo is normally handled as a bitmap because its tone and detail are represented pixel by pixel.

The input tone treated as the darkest available value. Moving it can deepen shadows, but pushing it too far clips distinct dark details into one solid region.

A broad adjustment that moves much of an image lighter or darker. Use it to correct the overall exposure before dithering, then check that highlights and shadows still contain useful separation.

Loss of detail when multiple tones are forced to the same maximum white or minimum black value. Clipped hair, clothing, or facial shadows become flat regions that no dither can reconstruct.

The difference between light and dark parts of an image. More contrast can separate a subject from its background, but too much can erase midtone detail and create harsh solid areas.

The selected portion of the source image that remains in the final composition. Crop before final sizing so the subject receives enough pixels and the tone adjustments respond to the actual frame.

A method of simulating continuous tone with patterns of a smaller set of values, commonly black and white dots. Local dot density creates the appearance of highlight, midtone, and shadow even though each output pixel is binary.

A compensation that shortens engraved scan segments to account for the physical width of the laser mark. It belongs to machine calibration. The useful value depends on the spot and material response, not only the image file.

Dots per inch, a density measure used to describe raster scan spacing and the pixel grid at a physical output size. In LightBurn's scan settings, DPI is related to line interval by DPI = 25.4 divided by interval in millimeters. Higher is not automatically better.

A dithering family that passes the difference between an original tone and its black-or-white decision into neighboring pixels. Floyd-Steinberg, Jarvis, Stucki, and Atkinson use different neighborhoods and weights, producing different dot fields.

A widely used error-diffusion algorithm that distributes conversion error into a compact set of nearby pixels. It is a practical baseline for photo tests because it produces an irregular, economical dot pattern without a large repeating matrix.

A nonlinear tone adjustment that primarily moves midtones while affecting the endpoints less than a simple brightness change. Gamma is useful for opening a shadowed face or controlling middle values before the image is dithered.

An image containing multiple values between black and white. It is not the same as a one-bit dither. Some laser modes vary power with grayscale, while others convert grayscale into binary marks.

A tone-simulation method that varies the size, spacing, or arrangement of visible spots. It can create an intentional printed texture. It differs visually from the irregular dots of many error-diffusion methods.

A laser-software setting that determines how bitmap pixels are converted into machine output. Examples in LightBurn include Threshold, Ordered, Dither, Jarvis, Stucki, Grayscale, and Pass-Through behavior for prepared images.

An operation that swaps light and dark tone values. It is commonly needed when the laser makes a dark material lighter. Confirm whether a control changes only the preview or the engraving signal.

An error-diffusion method that spreads error across a broader neighborhood than Floyd-Steinberg. It often creates smooth photographic transitions, but the broader pattern is not automatically best for every size and material.

The physical distance between neighboring raster scan lines, commonly expressed in millimeters. Too little spacing can cause overlap and muddiness. Too much can leave gaps. It is mathematically linked to DPI.

Lines per inch, another way of expressing raster scan-line density. Software may use LPI and DPI interchangeably in a scanning context even though printing terminology can distinguish them.

A controlled set of small engravings used to compare machine settings on the actual material. A useful test changes one or two labeled variables while keeping the source file, focus method, and surface preparation fixed.

An image or engraving signal whose light and dark values are reversed. It helps produce a visually positive result on surfaces where laser exposure creates a lighter mark, such as many slate processes.

Extra head travel beyond the image boundary that lets a gantry accelerate and decelerate before changing the laser output across the artwork. Insufficient overscanning at high speed can contribute to darker edges because the head slows near direction changes.

LightBurn's mode for engraving an externally prepared image as-is instead of applying another image-processing mode. Use it for a final two-color bitmap whose size, DPI, polarity, and dither were already decided.

The smallest addressable cell in a raster image. For a one-bit bitmap, each pixel is an explicit black-or-white decision. At final size, the pixel grid should align with the intended scan density.

The mapping between image tone, laser exposure, and the visible result on a material. Correct polarity depends on whether exposure creates a lighter or darker mark. It should be tested rather than inferred from screen appearance alone.

A pixel-grid image, in contrast with a vector made from mathematical paths. Photographs are raster images. Their detail at a physical size depends on pixel dimensions and the process's resolvable spacing.

A broad term for the amount or density of detail represented in an image or reproduced by a process. Pixel dimensions, DPI metadata, laser spot size, scan interval, and material response are related but distinct forms of resolution.

Creating a new pixel grid when an image is resized, rotated, or otherwise transformed. It is useful before dithering but risky after dithering because it can delete, duplicate, or soften the final binary marks.

A local-contrast adjustment that makes edges appear more distinct. Moderate sharpening can help detail survive reduction. Too much creates halos and noise that become false marks after dithering.

The original or highest-quality available photo used to begin preparation. Return to this nondithered version when changing crop, physical size, or DPI instead of resizing a finished one-bit output.

An error-diffusion method with a broad distribution pattern often used for smooth-shaded photographic images. It is worth comparing with Jarvis and Floyd-Steinberg on the same final-size crop because material response can reverse a screen preference.

A conversion that assigns every pixel to black or white based on whether it falls above or below a cutoff. It suits art that is already two-color. A single threshold usually discards too much tone to represent an ordinary photograph well.

The span and distribution of values from the lightest meaningful detail to the darkest. A useful engraving file separates important regions within the smaller range the material and process can reproduce.

Artwork described by mathematical paths, shapes, and fills rather than a fixed grid of photo pixels. Vectors are excellent for logos, outlines, and geometry. Tracing a photograph into vectors usually removes or stylizes its continuous tonal detail.

The input tone treated as the brightest available value. Moving it can brighten an image, but excessive adjustment clips subtle highlights into empty or fully marked areas after polarity is applied.