|
I am going to bale out of this forum for a while. It is not the best
format to present an idea. Not having an ability to provide pictures
and drawings makes it too difficult to explain an idea leading to
excess verbosity and disagreement through misunderstanding. I have an
excellent Kodak booklet on dye transfer that gives a detailed
description for doing both separation negatives from transparencies and
in-camera separation negatives. Here is a quote from the start of this
booklet on dye transfer, "Although more direct methods of making color prints have become available, the Kodak Dye Transfer Process continues to have important advantages in many professional applications. It offers unique possibilities for the control of color balance and contrast, as well as unexcelled photographic quality." I supplied the emphasis. I contend that those words are as valid today as the day they were written. Dye transfer can be considered a two part process. It has a front end that consists of making RGB separation negatives and a back end that consists of "printing" matrices carrying color dye. That back end process is no longer needed as the latest inkjet printers from various companies provide very good color reproduction (Epson K3 inks, MIS K4 emulation of Epson K3 inks at 1/4 the cost, HP 12 color inks) and in the case of B&W printing, Paul Roark's "Carbon on Cotton" process comes close enough to photographic print DMAX and is far more archival (Paul Roark definitely qualifies as an artist/scientist of the highest order). This is fortunate because the back end of the dye transfer process was a messy, finicky operation that few could ever hope to master. It is also fortunate because Kodak no longer makes the necessary materials to do the back end and I am not aware of other sources. What continues to be of interest is the front end of the process which is capable of achieving the highest possible standard of color reproduction or in Kodak's words unexcelled photographic quality. With Adobe Photoshop it is completely feasible to use any panchromatic (i.e. full spectrum from about 400 to 720 nanometer) B&W film with sufficient dimensional stability to create the RGB separation negatives because the curves are entirely under your control. While the seductive pleasure of digital imaging reigns supreme these days, what digital cameras offer is primarily ease of use and consistency of process for photographers who mostly are unaware they are giving up unexcelled photographic quality because most have never had the opportunity to see how good a dye transfer can look. The only current cameras I am aware of that come close this level of quality are the newer Hasselblad H3, H4 and selected backs which use the latest 49 to 60 Mpixel digital sensors by Kodak and remove Moire' as a software process using Phocus 2 rather than by essentially blurring the image (as all other digital cameras do). The cost to add a 49K Mpixel Hasselblad back to a V system camera is $14K so over twice the cost of the Nikon D3x (which most critics regard as the best of the full frame digital cameras). The cost of a new H4 Hasselblad minimal camera system is $50K. In comparison, the cost of a 120 roll film camera, RGB filter set and a suitable flatbed scanner is in the $200 to $800 range and this system will have similar image quality and slightly better color quality for suitable subjects (landscape, still life, much of commercial photography, etc.). Excepting the Pentax K7 (temp range to 14 degrees F and 15 Mpixels) most digital cameras have a stated operational temperature range that ends at 0 degrees C (32 degrees F) and suffer the disadvantage of needing batteries ... and for many purposes a laptop too, which also won't work well in the cold and also needs batteries. I have several other projects that need attention - building a state of the art passive solar house and experimental natural sustainable farm that will grow food throughout the year using passive solar techniques, etc. As I have time I plan to put together an updated version of the excellent information Kodak provided on dye transfer that works with the advantages of Adobe Photoshop and either put this at a website or on CD. I will try to put a notice here if anyone is interested. Finally, it is true that color and image quality are only one aspect of making photographs that transcend to the level of art. And while unexcelled photographic quality is not a necessary capability for accomplishing this, it can be a useful one that has to some extent been given up in the rush to adopt whatever the Megapixel Marketers are offering up as unsurpassed quality. One of my own interests is outside of the domain of this forum, - creating prints or Giclees of paintings that very precisely reproduce them at affordable costs for a not excessively wealthy collector to enjoy. This RGB sep neg process seems an ideal one for that purpose. I have been seeing 8x10 Linhof view cameras in the $1200 to $2000 range on eBay capable of creating image quality that no current digital camera could begin to approach. (Linear resolution comparisons can be estimated by taking the squareroot of the ratio of mexapixels. So a 60 Mpixel camera is about SQRT(60/10) = 2.4 times or SQRT(60/12) = 2.2 times better in linear resolution than a 10 or 12 Mpixel camera. It is generally accepted that 10 to 12 Mpixel cameras are comparable to good 35mm film results. By this standard the very best of non scanning digital cameras, a Hasselblad H4 using Phocus 2 software, is roughly comparable to a good 6x7 cm film image result in resolution making 8x10 film an over 3Xs higher resolution choice with the added benefit of more accurate color, at a far more attractive cost and with the advantages of more archival image storage. So, film is not quite dead yet and I hope B&W film will remain available for many years because it is capable of unexcelled photographic quality. ; ) Ed |
