Bill, thanks for the reply! I'm still trying to grasp the terms so please bear with me...
Say I have a roll of Ilford Pan F 50 and rate it at 32. Would I be Pulling the film at exposure and then need to have it Pushed at development? I'm not sure why this is a difficult concept for me to grasp but it really comes down to trying to understand how the terms are used. Thanks again! D > From: "William Robb" <[EMAIL PROTECTED]> > Reply-To: [EMAIL PROTECTED] > Date: Fri, 19 Oct 2001 13:21:44 -0600 > To: <[EMAIL PROTECTED]> > Subject: Re: Pushing and Pulling film > > ----- Original Message ----- > From: "Delano Mireles" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Friday, October 19, 2001 12:43 PM > Subject: Pushing and Pulling film > > >> Could someone provide a concise and clear explanation on the > meaning of >> these terms and how you would use them to provide different > results? > > Maybe. > The term pushing is given to a process of extended from normal > development to attempt to compensate for under exposure. The > idea is that since an underexposed emulsion will not develop as > much density as required with standard development, extending > the development will increase the density to a useful level. > The problem with this is that when the manufacturer sets the > films speed point, it is set at the minimum amount of exposure > required to give a usable image. By definition, giving less > exposure will result in a less than optimal image. Shadow detail > that is lost to underexposure cannot be regained via extended > development. > Having said that, some films have characteristic curves that > tolerate underexposure better than others. Tri-X Pan, with its > very long toe is one such film. > Push processing C-41 film does not work at all. Anyone who says > otherwise is fooling themselves. The C-41 process is a develop > to completion process, and any additional development merely > adds to the base density. > And yes, I have proven this. > The now discontinued Kodak PJ800 film was designed to be > pushable (according to Kodak, anyway). If you have a look at: > http://www.komkon.org/~wrobb/PJ800/index.html > (please note, this page is over 500kb, and the server seems a > bit slow at the moment.) > paying particular attention to the grey scale, you will see that > as the film received less exposure, shadow detail was definitely > lost. I followed Kodiaks recommendations for push processing, so > the results are true. > I have heard that E-6 films have better response to pushing, but > I have no experience in that regard. > > Pull processing is exactly the opposite of pushing. The film is > given less development than normal to attempt to compensate for > over exposure. > Again, it doesn't work with C-41, because the mask layer doesn't > get full development, and this introduces cross curves and all > sorts of ugly colour problems. Also, since the image is formed > by translucent dyes, over exposure is less of a problem. Very > few C-41 films will block up to the point of unusability with > moderate (4 stops or less) over exposure. > Black and white films will respond to pull processing with > fairly good results. This is an area where T-Max films are > great. They have a very long, straight curve, so under > development can be used to compensate quite successfully. Since > conventional black and white images are formed by opaque silver > grains, it is important to not overexpose by too much, or the > film will block up the highlights. Pull processing will cure > this by restraining development in the highlights. > Many Zone System photographers routinely use a speed point > several stops below the manufacturers recommendation with the > intention of pull processing. This ensures that the very > important shadow details are secured, while at the same time > ensuring that highlights are not blown out. > In fact, this is really what the Zone System is about. > E-6 films will also respond fairly well to some pull processing, > and since over exposure is a good way to ruin an E-6 film, pull > processing is always preferable to standard processing with E-6 > film that has knowingly been overexposed > William Robb > - > This message is from the Pentax-Discuss Mail List. To unsubscribe, > go to http://www.pdml.net and follow the directions. Don't forget to > visit the Pentax Users' Gallery at http://pug.komkon.org . - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
