Archived posting to the Leica Users Group, 2003/12/05
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Dante Stella wrote: > > On Dec 5, 2003, at 2:37 AM, Eric Welch wrote: > > > Here's one inaccuracy in your text: > > > > > > "-- Film has a much higher dynamic range than digital - 15 stops on > > TMY, or a 32768:1 ratio. That means that you capture everything in the > > scene and can go back and adjust up or down at will later." > > > > Not true. Film - even black and white, does NOT contain all details in > > a scene. Even ideally processed, it will not be able to cover the > > dynamic range of many, many scenes, especially contrast daylight. > > Neither can digital. But that's my point. Neither of them can, and > > film is not better. > > > I'm trying to think of a definition of the term "dynamic" that would make the statement that film has a "dynamic range" of 15 stops make any sense. I looked it up in several sources on the internet as well. The one definition I can think of is "in your wildest dreams" which can be found in the "Rabiner Pronouncing Dictionary of the English language". There are ten stops or "zones" in the zone system. Eleven if you count zone 0 which is film base fog and exists only in the neg not in the print. (Big deal) So I'm curious where they pulled they extra 4 stops out of!?! If they are using the term "dynamic" as "useful" which is a stretch then film only has about 4 or 5 stops which contain detail. And are thus "dynamic"? "Jumps right OUT at you!" The detail I get just kind of sits there but nevermind. And why they picked a thinner emulsion film like T-Max 100 to have that? A thicker emulsion 400 speed film would more likely be able to have a wider range and perhaps with special developing agents like Pyrocatechin to make developers designed for recording sun spots and atomic bomb blasts and severely lower the speed of your film. Not so useful in obtaining normal looking results in a typical scene. Mud I say! Mud! No separation. (Or getting something resembling "normal" results from Tech Pan which is really a high contrast film, ultra thin emulsion) No only 4 or 5 of the 10 or 11 stops you'd get in black and white film have any real interest. A few less in ColorNeg. And a few stops less than that in color slide. Which hasn't left you with much. Mark Rabiner Portland, Oregon USA http://www.rabinergroup.com No Archive Hold the Anchovies - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html