Hi Leonard, Actually, this will be ok. This lens is so physically large I will not be using any movements with it. I was really pleasantly surprised to get f16. I was prepared to be happy with f8. The interesting thing here, which is probably intuitive anyway, is the difference between putting the stop in the front vs. the rear. Interesting what you said about the ND filters. I hadn't thought of that. No way I'd even try slotting the barrel. It's a heavy aluminum casting, and I have no idea where the glass starts and ends in this thing. I could send it off to Steve Grimes, but that would blow the budget for the whole project. This is a 4x5 camera that combines a Speed Graphic fp shutter with a set of three military aerial recon lenses I've acquired over the last few years. There's a 3 inch wide angle ( the hugest of them all, no iris, but at least a place to put one), a 6 inch normal( the most compact, with an iris, and will have full movements), and this medium size 12 inch lens. Like I said, it has no iris, and no place to put one, except, as I've discovered, right in front!
Gene Leonard Robertson wrote: > > Gene, > Is there any chance you could slot the side of your lens barrel for > waterhouse stops? I know this is much easier said than done, but if the > front/rear iris is killing your coverage, it might be something to > consider. Depending on the f-stop range you normally use, you may not need > too many individual stops. ND filters might be used to fine tune exposure, > since they are available in 1/3 stop increments. > > > > Leonard > > At 02:22 PM 12/17/2001 -0800, you wrote: > >Hello All, > > > >Thanks for the excellent information. I thought I would share the > >results of a little experiment I just performed. I was very curious if > >the 12" lens without any iris would cover 4x5 at infinity and f16 with > >an external iris. I made a black paper f16 aperture and taped it to the > >rear of the lens. No way. Nowhere near enough coverage. Moved it to > >the front. Just covers, with a little to spare. I haven't done the > >experiments to determine the proper settings for my 6 inch with unmarked > >iris, but I will. > > > >Gene > >_______________________________________________ > >Cameramakers mailing list > >[EMAIL PROTECTED] > >http://rmp.opusis.com/mailman/listinfo/cameramakers > > > > _______________________________________________ > Cameramakers mailing list > [EMAIL PROTECTED] > http://rmp.opusis.com/mailman/listinfo/cameramakers _______________________________________________ Cameramakers mailing list [EMAIL PROTECTED] http://rmp.opusis.com/mailman/listinfo/cameramakers
