JPEG (JPG)

There is no universal JPEG quality number: encoder scales differ. Start from the master, choose a setting that preserves visible detail at the target size, and compare candidate exports side by side. Follow a production partner's explicit preset when supplied.

The GIMP documentation explicitly cautions that quality numbers differ between applications. Instead of copying a slider value, compare two or three exports from the same master at the intended size, with special attention to sharp transitions, gradients, and fine texture. Keep the smallest file that meets the actual visual and production criteria, if size matters.

Export dialogs differ. Photoshop and GIMP offer JPEG quality and metadata options; ImageMagick exposes command-line controls. Confirm the installed version's behavior and inspect the output instead of relying on similarly named sliders.

Photoshop and GIMP expose different save/export choices; ImageMagick is useful for scripted conversions and inspection, but command flags must be recorded to make results repeatable. A camera may apply processing before the JPEG is ever edited. Confirm source handling, profile behavior, orientation, and export settings in the installed versions.

Open the exported file in a second viewer or inspection tool; check dimensions, orientation, format, profile, and whether the intended recipient's software accepts it. A valid JPEG can still be the wrong artwork for a product.

Check both semantic and technical validity. A parser may accept the JPEG, yet the image can still be the wrong size, wrong crop, wrong background, or wrong product revision. The last check should use the same receiving software and template the maker will use, or an equivalent approved intake process.

Watch for unexpected auto-rotation, profile removal, too-small dimensions, unwanted white backgrounds, visible block or ringing artifacts, and mismatch between the saved export and the editable source.

If a JPEG looks sharp in the editor but soft after delivery, verify that the export did not resize the image or use a low-quality preset. If it appears sideways, inspect orientation metadata and whether the receiving software honors it. If color shifts, compare profile handling before changing the artwork's colors.