How to Print Locket Size Photos and Manage Alternator Noise in Your Setup
Knowing how to print locket size photos is a surprisingly specific skill that requires getting dimensions exactly right on the first attempt. Standard lockets take photos between 15mm x 15mm and 25mm x 30mm depending on the design, and the margin for error is nearly zero. A photo that is 2mm too wide will not fit.
This guide also covers a related technical challenge that photographers face in mobile setups: alternator noise filter options for car-based shooting rigs, plus tips on vintage facebook cover photos that benefit from the same careful size management, and how 24 megapixel print size calculations work when sizing down to locket dimensions.
Step-by-Step: How to Print Locket Size Photos
Measuring Your Locket First
Before opening any software, measure your locket’s interior compartment with a millimeter ruler. Note both the horizontal and vertical dimensions. Round down by 1mm on each side to account for the slight gap needed for the photo to slide in and out cleanly.
If you want to print locket size photos for a standard oval locket, most measure 18mm x 23mm inside. For round lockets, interior diameters typically run 18mm to 25mm. Measure your specific piece before printing anything.
Setting Up Your Print File
Open your image in Photoshop or a free alternative like GIMP. Go to Image > Canvas Size and set your dimensions to the measured locket size at 300 DPI. At this scale, 300 DPI produces approximately 210 x 270 pixels for an 18x23mm opening, well within the resolution of any modern camera.
Understanding 24 megapixel print size limits is important here. A 24MP sensor captures enough detail to print at full quality up to roughly 20×30 inches at 300 DPI. Cropping to locket dimensions leaves you with a tiny fraction of the original file, so quality is never an issue regardless of which modern camera you used.
Alternator Noise Filter for Mobile Shooting Rigs
If you run photography equipment from a vehicle, alternator noise filter options become relevant. Alternator whine is an electrical interference that enters audio and video equipment through shared power lines. It creates a high-pitched whine that rises and falls with engine RPM.
The standard fix is an inline ground loop isolator or an alternator noise filter installed between your power source and your equipment. For camera batteries charged via car power, use a quality inverter with a built-in filter. For audio equipment in mobile interview setups, a DI box with ground lift on the output works reliably.
Vintage Facebook Cover Photos and Print Sizing
When you pull vintage facebook cover photos from your archive to restore and reuse, they often come in low resolution by modern standards. Facebook’s cover photo dimensions are 820 x 312 pixels, which is roughly a 3:1 ratio at screen resolution.
Upscaling a vintage photo for this format works best with AI-based upscaling tools like Topaz Gigapixel or Lightroom’s AI Denoise and Sharpen tools. These recover detail that traditional interpolation blurs. Once upscaled, apply a light grain overlay to match the vintage aesthetic rather than fighting it with over-sharpening.