Some years back in either Photo Techniques or Camera and Darkroom there was an article in which he author gave a formula to determine the sharpest aperture to use under virtually every circumstance. In use, you set up, adjusted camera movements and then measured the difference, in mm, between bellows extension when focused on the near object and the far object that you wanted in focus. Bellows were then placed half way between these points and the taking aperture determined via the formula. I've used this successfully for a long time - but I can't find the damned article. I put it somewhere "safe" - and that was the kiss of death

I did use a spreadsheet programme to create a small chart which I laminated and remains in my bag, but I'd like to get hold of the formula again to do some refinements.

Anyone remember it? Anyone have the formula?..........Anyone?

Thanks

Bob H