When selecting a source image for photo engraving on wood and slate, several factors come into play to achieve optimal results. First and foremost, high-resolution images are essential; ideally, the source image should be at least 300 DPI (dots per inch). This high resolution ensures that the details are sharp and well-defined, which is crucial for the engraving process.

Images with good contrast tend to work best. High-contrast images, where the subject stands out distinctly from the background, help in creating a more striking engraving. Avoiding overly busy or complicated backgrounds can also enhance the final output. Black and white images or monochromatic tones are particularly effective since they translate well into engraving, creating clear differentiation between light and dark areas.

Additionally, images with clear outlines or defined shapes work better than those with smooth gradients and soft tones, as engravers may struggle to replicate subtle transitions. Simple, bold images such as portraits, logos, or nature-themed graphics generally yield the best results when engraved on wood and slate. Ultimately, the selection of the right image is vital for successful engraving outcomes.