The largest print size for a photo depends on the resolution of the image. If you have a high-resolution image, you can print it to a larger size without losing quality. However, if you try to get a large print from a low-resolution image, you will need to print it to a smaller size or the image will start to look pixelated. The exact size can be determined by opening the file in Photoshop or a similar editing program. You can always send through your images to email@example.com or contact us and we’ll be able to check your file and advise you.
While both Giclee and Lambda printers print at 300DPI up to sizes of 30×40 inches, above this size printers such as the Lambda, print at 200DPI. However, you can print it to a larger size if you are willing to accept some loss of quality.
The other determining factor is the quality of the lens on the camera used to take the picture, and whether any blur has been produced by camera shake. The pixel dimensions can also have the resolution increased in Photoshop, often to a factor of four, so an A4 image could be printed at A2 if the lens and sharpness was ok to begin with.