30 x 40 cm at 200 DPI: Real Photo Print Test
30 x 40 cm is a common large photo print size (often sold as 16-inch). This test checks how a 200 DPI file looks when printed on RC luster paper and inspected at 30 cm.
What the close-up shows
At 30 cm, 200 DPI performs better than the A4 150 DPI test: 5-6 pt text is still soft, but strokes hold together better; fine line pairs separate more cleanly; and the photo-like scene retains smooth gradients without obvious banding. It is not as crisp as the A4 300 DPI print, which is expected from the lower pixel density.
| Element | Observed at 30 cm |
|---|---|
| 5-6 pt text | Soft but mostly readable; edges less clean than 300 DPI |
| 10 pt and larger | Comfortable to read |
| Fine line pairs | Better separation than 150 DPI; finest pairs still merge |
| Gradients and colour patches | Smooth, with clear patch boundaries |
| Photo-like scene | Pleasant texture from the RC luster surface; detail remains intact |
Is 200 DPI enough for a 30 x 40 cm photo?
For a photographic print viewed at a normal distance, 200 DPI is a practical choice and this close-up supports that. If the print contains small text, fine technical lines or will be inspected in the hand, use 300 DPI instead. If the image is only 200 DPI at this size, check that it is genuinely 2362 x 3150 pixels - do not simply change the DPI metadata of a smaller file.
Cost and materials
Five prints in this batch - three A4 sheets, one A3 sheet and this 30 x 40 cm sheet - cost RMB 24.5 in total from one Taobao seller. The paper is RC luster photo paper; the listing specified Canon pigment ink and described it as water-resistant and fade-resistant. Paper weight was not listed, so the GSM is not recorded.
Why 200 DPI is a practical target here
At 30 x 40 cm, 200 DPI requires 2362 x 3150 pixels - about 7.4 megapixels. That is well within the output of most modern phones and cameras, even after moderate cropping. It is a useful middle ground: more detail than a 150 DPI poster, without the much larger file and slower processing of a 300 DPI print.
What this test does not cover
This was an RC photo-paper print, not a canvas print. Canvas has a woven texture that can hide some softness and change how fine detail appears. We have not tested canvas material or a 300 DPI version of this exact 30 x 40 cm scene yet, so the result should not be generalised to every large-format product.
Related tools
Canvas print calculator · Print size calculator · Canvas vs poster vs photo print · 300 vs 150 vs 72 DPI test