Some one keeps annoying me, says he must use 150mm lens, and since there is only few mm less when bellows extends to end of the flat bed, why don't do something about it?
Well, OK, OK, I will do it.
The result is satisfied, the solution-- make a thicker lens board.
in the image you can see I use two lens boards to simulate a thicker lens board for 150mm, one in black and one in silver. The infinity stop is exactly at the end of the bed.
Preview knob on shutter should be careful not to touch the strut.
View through the ground glass.
Tried to extend the flat bed to the limit, and found that the nearest distance to focus is 150cm, about 5 feet.
Alright, I take it back, 150mm lens is coming back, and for this lens, I need to re-grind the lens cam, that is another hard work!!