There was a carrier produced with a larger aperture to print black borders. It may be quite hard to find. You could try the German eBay site. I have seen lots of V35 stuff there in the past. You should use the pressure levers as any border you see when they are not applied means that the negative is not flat in the carrier. By coincidence, my other enlarger is a Durst M601. It is also a great machine. Alex