For 35mm enlargements I prefer to use a 75-80mm lens on the Setopla lens board. This creates a little more distance between the head and the baseboard so I don't bump my head all the time when focusing the image. A 50mm and a Latub will also work, especially if you need to make enlargements larger than 30x40cm from 35mm negatives. But for smaller prints, I prefer a 75mm lens for the reason stated above. Furthermore, it's generally easier & cheaper to find a Setopla than a Latub. And it's also easier to work with the Setopla because you can actually see what aperture you set the lens to; with the Latub, this is generally not possible.