Grain Focusing - discrepancies

[Bill Burk]

Process Cameras were all that way. Two cranks, one moves copyboard the other moves lens board. The film (think paper) plane is fixed. Some were vertical and you had to stand on a stool to look down at it. Most were horizontal and the vacuum back was at a comfortable table level when open. The ground glass at eye level. There were tape measures that the cranks were tied to that indicated percent enlargement/reduction. You just moved the cranks until both indicated the same ... then you were in focus. You could use the ground glass to calibrate the tapes. But most of the time you dialed in and shot.

 

[MattKing]

Process Cameras were all that way. Two cranks, one moves copyboard the other moves lens board. The film (think paper) plane is fixed. Some were vertical and you had to stand on a stool to look down at it. Most were horizontal and the vacuum back was at a comfortable table level when open. The ground glass at eye level. There were tape measures that the cranks were tied to that indicated percent enlargement/reduction. You just moved the cranks until both indicated the same ... then you were in focus. You could use the ground glass to calibrate the tapes. But most of the time you dialed in and shot.

My wife is grudgingly supportive about the 4x5 enlarger I wheel into our bathroom.

A process camera would bring about a definitive NO!

 

[Steve Smith]

A process camera would bring about a definitive NO!

But it would make the enlarger seem more reasonable!


Steve.

 

[Mr Bill]

I think our enlargers are built the wrong way round!

They should have the light source, negative and lens at the bottom, projecting upwards onto a piece of ground glass...

This has actually been the standard setup for commercial printers (ie. package printers) for MANY years. A ground glass is used to focus and align all of the lens decks during initial setup. More familiar to the general public were film-based mini-lab printers; you've probably seen the operator sitting at a desk-like workstation to handle the negatives. Above is the lens tower and the paper transport system.

These systems have their own difficulties, one of which is the tendency for paper dust to fall out of the lens tower, onto the negative stage.