Archived posting to the Leica Users Group, 2002/01/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]thanks for the advice. i do have a little xrite densitometer. one thing you can always count on every roll: some dmax (the leader) and some film base (space after last frame). i usually file both peices in with my negatives so i can check them at a later date. may i ask why do you pick -3 and +5 from normal exposure? this corresponds to zone II and zone X. i usually benchmark to zone I (D=FBF+0.10) and VIII (D=FBF+1.20). thx - -rei > From: "Don Dory" <dorysrus@mindspring.com> > > Rei, the only sure test would be to create a test strip much as the > commercial labs use. First frame blank, second frame gray card exposed per > the meter, third frame minus three stops, fourth frame at plus five stops. > > To make this work you would have to create a standard set to compare with > known good chemistry or from a well set up commercial lab that runs > commercial test strips. > > The first frame tells you if your fix is any good or whether there is some > source of dichroic fog in the system. > > The third frame tells you the speed point of the process. This needs to be > looked at in conjunction with contrast as if this point rises as well as the > middle gray then contrast stays the same but everything is overdeveloped or > the fix is going south which you can tell from the blank frame. > > The second frame minus the third frame tells you the contrast index of your > system. If the developer is just going south you will see it in the > contrast assuming the FB + fog stays constant. > > The fifth frame indicates ability to create dMax, this would be important if > you were experimenting with higher dilutions. > > All of the above implies the possession of a densitomiter or access to one. > > E-mail me if you have any questions. > > Don Dory > dorysrus@mindspring.com > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html > - -- Rei Shinozuka shino@ubspainewebber.com 212-713-6256 FAX: 212-713-1482 UBS Warburg Fixed Income Quantitative Research, UBS Warburg LLC 1285 Avenue of the Americas, 11th Floor, New York, NY 10019-6028 ----------------------------------------------------------------------------- "The X Consortium requests that the following names be used when referring to this software: X, X Window System, X Version 11, X Window System, Version 11, X11." (NOT "X-WINDOWS"!!!) -X man page (parenthetical exegesis mine) - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html