Gregg MacPherson

Nicholas, sorry I wasn't clear, that throat diameter is 54mm. The FFD I thought was 52mm, with sometimes some tiny change to allow the photons to dig a little into the film emulsion... I think the techs commonly use a depth guage with dial increments that border on being hard to interpret, so experience is needed to use them. It's an interesting thing to ponder. Maybe Dom will tell us what it's like.

Do you have a DoF calculator like a Kelly Wheel etc? They have special batteries made of never-go-flat-ium...

Hey Eric, curious how that worked out. Any info to share..?

Hey Jon. The tapes I used for mags etc were not gaffer tapes or variants on the duct tape idea, they were black paper "camera tape". Sort of like black masking tape, with black gum, and came with the confidence that goo would not be stuck to the mags years later if it was accidentally left on. Very useful, an aid to adaption and improvisation... There are plenty of people around who still have the practical knowledge to help. But one significant problem that exists is that there are one or two vain nitwits who know too little and say too much on the internet. There is at least one on this forum in fact. So people are misled.

sorry, an interrupted message....carrying on...One would need two layers of Shuretape CP 743 to get the same opacity as the old Scotch tape I had. It's very easy to test these for yourself. Put some on the end of your mag light, turn the lights off and see. Use a meter if you like. Scotch do have a tape with comparible opacity to the old version...called 235 I think. Same sort of price as the Shure one, but twice as opaque. And if it's like the old Scotch, there will be no residue on one's gear, many years later.....

Be aware that not all black paper tapes are light tight to the same degree. Used to be that Scotch made a very opaque tape. A leftover here calls itself Klebeband (no idea what that means). Years later I looked for a replacement. The suggested Shuretape CP 743 was not as opaque as the Scotch I had before. One would need t

I agree with Stuart on this. And further, the required final result, clean vs dirty, in the face of the environment, clean vs dirty, should determine how one proceeds. Having the pre-set notion of only checking the gate at a mag change is a bit perilous. Having the mental pre-set that this is how a documentary should probably be done may also be perilous. Why not avoid the dirt and hairs in the first place rather than zooming in. Zooming in compromises the original intention of the photographer. Unless, perhaps he had no definitive intention in the first place, was just fishing around for a fuzzy possibility that an editor might later put a rectangle around for him. White cotton gloves anybody..?

I know this doesn't help fix the problem, but to prevent it, you must keep the gate clean. The gate here is extremely dirty.

What an amazing guy he was. A while back I saw a doco on youtube on him designing the penelope. He was a very inspiring man

It's a mad venture...in a pleasant way.. :)

It's just a stunning piece....a wonder. Thanks Mark.

The cheapest, simplest way might be to process your B&W as reversal. So experimenting with the processing to see if you get a useful image that way might be a next step. I never did reversal processing, but I think in simple (simplistic?) terms, after development a bleach washes away the exposed silver, then the remaining emulsion is exposed to light, then developed and fixed. You can find descriptions online. Found this one after writing... https://en.wikipedia.org/wiki/Photographic_processing

I wish it was as easy as explaining the acronym :rolleyes: I always stumbled wondering what the minimum contrast is that the human eye can discern. Who's eye. We're all different. Some people have extreme acuity with seeing. There is probably a definition explaining that, somewhere, in very, very fine print, at very low contrast, so we can almost read it.