Pentax 645

轉接環只能增加鏡頭與底片之間的距離，無法縮短。這些接環比 Pentax 645 更靠近底片，因此原則上其鏡頭可以轉接上去並仍能合焦無限遠。沒有記錄法蘭距的接環不列出，而不是靠猜。

• Zenza Bronica ETR 69 mm
• Contax 645 64 mm
• Novoflex A-mount (follow-focus adapter) 63.3 mm
• Mamiya 645 63.3 mm
• Ricoh 126C-Flex 62.22 mm
• Hasselblad H-mount 61.63 mm
• 1KSR-2M 61 mm
• OCT-19 61 mm
• Mamiya Press breech-lock 60.1 mm
• Mamiya 7 59 mm
• Panavision PV-mount 57.15 mm
• 1KSR-1M 57 mm
• Vivitar TX 56.25 mm
• Mamiya 6 56.2 mm
• Topcon UV bayonet 55 mm
• T-mount (T2, M42×0.75) 55 mm
• Mini T-mount (M37×0.75) 55 mm
• Sigma YS mount (M42×0.75 preset) 55 mm
• Pentina bayonet 54.95 mm
• Werra bayonet (Carl Zeiss Jena) 54 mm
• Leica S-mount 53 mm
• Arri PL 52 mm
• 16-SP 52 mm
• Arri B 52 mm
• Arri Standard 52 mm
• Tamron Adaptall 50.7 mm
• Praktina breech-lock bayonet 50 mm
• Icarex bayonet (BM) 48 mm
• B4-mount 48 mm
• Contax N mount 48 mm
• KMZ Zenit DKL-mount 47.58 mm
• Leica R-mount 47 mm
• Nikon F-mount 46.5 mm
• Olympus OM-mount 46 mm
• Contarex bayonet 46 mm
• Yashica MA-mount 45.8 mm
• Braun Paxette Reflex DKL-mount 45.7 mm
• Kodak Retina DKL-mount 45.7 mm
• Voigtländer Bessamatic DKL-mount 45.7 mm
• Voigtländer Vitessa T DKL-mount 45.7 mm
• Contax C/Y-mount 45.5 mm
• Mamiya Z (ZE) bayonet 45.5 mm
• Pentax K-mount 45.46 mm
• M42 screw mount (M42×1) 45.46 mm
• M39×1 Zenit SLR thread 45.2 mm
• Exakta bayonet 44.7 mm
• Minolta / Sony A-mount 44.5 mm
• Samsung Kenox mount 44.5 mm
• Rollei QBM 44.5 mm
• Argus C44 bayonet 44.45 mm
• Praktica B-mount 44.4 mm
• Kiev Automat bayonet (Kiev-10/15) 44 mm
• Arri LPL 44 mm
• Pentaflex (16 mm cameras) 44 mm
• Praktiflex M40×1 screw mount 44 mm
• Canon EF mount 44 mm
• Canon EF-S mount 44 mm
• Sigma SA-mount 44 mm
• Minolta SR-mount 43.5 mm
• Fujica X-mount 43.5 mm
• Petri Bayonet 43.5 mm
• Rectaflex bayonet 43.4 mm
• Yashica Pentamatic bayonet 43 mm
• Altix-n bayonet 42.5 mm
• Wrayflex M41.2 screw mount 42.05 mm
• Start bayonet (KMZ Start) 42 mm
• Canon FL mount 42 mm
• Canon FD mount 42 mm
• Canon R mount (Canonflex, Super-Canomatic) 42 mm
• Argus C3 33 mm screw mount 41.9 mm
• Miranda bayonet / M44 screw 41.5 mm
• Agfa Ambi Silette bayonet 41.3 mm
• Konica F-mount (Bayonet Mount I) 40.5 mm
• Konica AR-mount 40.5 mm
• Aaton mount 40 mm
• Nikonos 39 mm
• Four Thirds 38.67 mm
• Sony 1/2" TV bayonet mount 38 mm
• Panavision SP70-mount 38 mm
• Alpa 35mm bayonet 37.8 mm
• Minolta V-mount 36 mm
• 1/2" TV bayonet mount 35.74 mm
• Contax rangefinder mount (Contax/Kiev) 34.85 mm
• Nikon S-mount 34.85 mm
• Hasselblad XPan 34.27 mm
• Robot M26×0.5 screw mount 31 mm
• Kiev-16U 31 mm
• Contax G-mount 29 mm
• Olympus Pen F bayonet (half-frame) 28.95 mm
• Meopta Opema 38 mm screw 28.8 mm
• Leica thread mount (M39×26 tpi, LTM) 28.8 mm
• Narciss M24×1 screw mount 28.8 mm
• Leica M-mount 27.8 mm
• Chaika M39 half-frame thread (27.5 mm) 27.5 mm
• RED ONE interchangeable mount 27.3 mm
• Pentax 110 27 mm
• Fujifilm G-mount 26.7 mm
• Samsung NX-mount 25.5 mm
• JVC 1/3" bayonet mount 25 mm
• Canon RF mount 20 mm
• L-Mount 20 mm
• Micro Four Thirds 19.25 mm
• Sony FZ-mount 19 mm
• Hasselblad XCD mount 18.14 mm
• Canon EF-M mount 18 mm
• Sony E-mount 18 mm
• Fujifilm X-mount 17.7 mm
• C-mount 17.53 mm
• Nikon 1-mount 17 mm
• DJI DL-mount 16.84 mm
• Nikon Z-mount 16 mm
• CS-mount 12.53 mm
• D-mount 12.29 mm
• M58×0.75 mm mount 12 mm
• Pentax Q-mount 9.2 mm
• Samsung NX-M (NX mini) 6.95 mm