I've not seen an enlarger yet that could not accept any negative smaller than the maximum size specified for the machine. This assumes that the correct condensers, if so equipped, and negative carriers are available. I have no problem using 35mm negatives with my Omega D series enlarger. My enlarger is equipped with the Chromega II light source, so condensers are not part of the setup. The largest available light mixing chamber works fine for all formats. That said, making small 4x6 prints from 35mm negatives with the 50mm lens attached is not practical. There is no way to get the head close enough to the baseboard. If you could, exposure times would be unreasonably short. The solution is to use a longer focal length lens. Something around 80mm gives enough distance to work comfortably when making small prints. A 50mm lens fitted to this enlarger is better suited to making 8x10 and larger prints from miniature negatives.