New from William Optics - A precision 2" prime focus adapter for Canon EOS cameras (Short) # P-PAC • One-piece adapter made from a single block of high grade aluminum and CNC machined for best quality • Integrated Canon EOS mount eliminates the need for a separate T-ring • Bypasses T-rings for much larger clear aperture of 46.4mm / 1.83" to minimize vignetting • Threaded to accept most 2" eyepiece filters * • Length: 49.6mm / 1.95"; Weight = 2.4oz / 68g • Ultra dark painted baffles inside reduce internal reflections and maximize contrast • Low profile adapter; suitable for use in prime focus photography applications where additional out-focus is not required (for example, with SCT or reflector telescopes) * Please note: Most 2" astronomy filters have an M48x0.75 thread specification. However, there are a few with an M48x0.6 specification. William Optics uses this M48x0.6 thread on this adapter. While the vast majority of 0.75mm pitch filters will work with this adapter (we tried 5 different brands and they all fit despite the pitch difference), there is a small possibility that your 2" filter may not thread on or thread all the way into this adapter. But since filters are so light, even a 1/4 turn is usually sufficient to latch on securely.