If I were determined to shoot 4x5 in flight, I would also consider a Fotoman or Chamonix Saber with a few Grafmatics ( plus 2x 10 shot Kinematics in my case ). This might even be a good candidate:

http://www.ebay.com/itm/Fotoman-45sp...item4634986cfb

Bust seriously though, I get really nice 20" prints out of TMY2 negs in my Hasselblad and really nail it up there with 4-6 backs loaded up...

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