why is my focusing off?

[Monito]

More humidity makes negatives more flexible. Since it was just three negaives and none before the flood or since the flood, then humidity is surely the cause. It must have been just enough to go past the tipping point to allow popping.

Keep your darkroom dry and see if the problem never recurs.

 

[MattKing]

The humidity from the flood could also affect the focus and elevation locks and the stiffness of the bellows on the enlarger.

 

[Leigh B]

Negative buckling from the heat?
Try a glass neg carrier.

Yep. Exactly.

- Leigh