Colorize Historical Photos — Pro, on our server
Colorization is an interpretation of a document, not a correction of it. The monochrome photograph is the primary source; the coloured version is a reading of it made in 2026 by a neural network with no knowledge of your subject. DDColor was trained on modern colour photographs and their greyscale conversions, so what it produces is the most statistically likely colour for each region, given how those greys usually arise. That is genuinely useful — it is how a skilled restorer reasons too — but it is a probability, not a record. A researcher who keeps that distinction explicit gets all of the communicative power and none of the trouble that follows a confident, invented, uncited colour.
Write the caption before you publish the picture. The convention that works is short and blunt: name the original and its holding collection, then say plainly that colour was added digitally, in what year, and with which model. DDColor is the model here, and the tool always shows you which model ran; the model can change, so recording the one that produced a particular file is worth the ten seconds it takes. If a specific colour in the frame is actually documented — a regimental facing colour, a livery, a flag — correct it by hand afterwards and say in the caption that you did. Where the subject is a uniform, the military photographs page goes into that in more detail.
The tool is deliberately conservative about detail. It changes chroma and nothing else, returning a PNG at exactly the resolution you uploaded — up to 25 MB and 24 megapixels. Nothing is sharpened, nothing is filled in, no scratch is painted out and no missing corner is reconstructed. Damage that was in the scan is in the output, in colour. If a print genuinely needs its faces recovered before colour will read at all, the face restorer is the separate step for that and should be disclosed separately; if the master scan is too small to reproduce, enlarge afterwards with the on-device upscaler rather than asking the colorizer for resolution it cannot give. The wider argument for keeping these steps distinct is on the old photos page.
Where archive material goes when you press the button. Colorization is a Cloud HD tool, which means it is the exception to the rule that MiniPx never uploads your images: the file goes over an encrypted connection to our server, is processed in the United States on Cloudflare R2 storage and a Modal GPU, and is deleted when the run finishes and in all cases within 24 hours. It is never used to train anything and it is never shown to anyone. If you are working under an institution’s licence terms, that retention window is the fact they will want in writing — and everything else you do on MiniPx, from cropping to converting, happens without the file leaving your machine at all.