mike@asgb.UUCP (Mike Rosenlof) (06/04/85)
> Was there a note here recently about using HC-110 to develop > technical pan film? If anybody has tried to do this for > pictorial photography I'd like to hear how it worked out. > > According to the data sheet I have, even a really dilute solution > of HC-110 still gives a contrast index of about 2, which is > normally considered to be too hard. Maybe there's a trick... > I wouldn't be TOO hopeful here. Tech pan is such a high contrast film that you need developers specifically designed to produce low contrast results. It may be possible to try something like water bath development which is normally used to produce low contrast negs. See Ansel Adams "The Negative" for a description. I suspect it would be easier and more predictable to just go with one of the conventional developers for tech pan. Kodak's pushing their liquid technidol, which I'm about to try soon, but it's awfully expensive. Mike Rosenlof ihnp4!sabre!\ hplabs!sdcrdcf!-bmcg!asgb!mike { ihnp4, ucbvax, allegra }!sdcsvax!/ Burroughs Advanced Systems Group Boulder, Colorado
jordan@ucbvax.ARPA (Jordan Hayes) (06/07/85)
In article <704@asgb.UUCP> mike@asgb.UUCP (Mike Rosenlof) writes: >> Was there a note here recently about using HC-110 to develop >> technical pan film? If anybody has tried to do this for >> pictorial photography I'd like to hear how it worked out. >> >I wouldn't be TOO hopeful here. Tech pan is such a high contrast film >that you need developers specifically designed to produce low contrast >results. I have had decent results with a dilution of HC-110 with tech pan. You can indeed get the low contrast characteristic from HC-110 if you spend some time reading the data sheets. Technidol is still the best, but HC-110 is also one of the recommended developers on the tech pan data sheet. /jordan ------- ARPA: jordan@berkeley.ARPA UUCP: ..!ucbvax!jordan
eric@rtech.UUCP (Eric Lundblad) (06/08/85)
> > Was there a note here recently about using HC-110 to develop > > technical pan film? If anybody has tried to do this for > > pictorial photography I'd like to hear how it worked out. > > > It may be possible to try something like water bath development which > is normally used to produce low contrast negs. See Ansel Adams "The > Negative" for a description. I suspect it would be easier and more > predictable to just go with one of the conventional developers for > tech pan. Ansel Adams used the water bath developer mostly with the older thicker film emulsions. As I understand it, todays thin emulsions don't hold enough developer when being put in the water bath to be usefull. I don't believe that any film makers recommend it anymore. In his book "The Negative", Ansel Adams talks about a "POTA" developer that can be used to control the contrast of tech pan. It is discussed on pages 251 and 254, but you should buy or find a copy to read. You can also experiment with HC-110 by using very dilute solutions of 1 part stock solution to 30 to 60 parts water. Stock solution is made by adding water to 16-ounce HC-110 concentrate to make 1/2 gallon (64 ounces). The developing times will be very long, say on the order of 20 to 30 minutes. You should agitate about every 2 to 3 minutes. The idea behind this is very similiar to the water bath developer. In this case, the dense areas of the negative exhasts the local amount of developer very quickly since it needs so much developer, and the solution is so weak. Therefore the dense parts spend a fairly small amount time actually developing because agitation is infrequent. The thin areas of the negative, however, place a very small demand on the developer, so they spend almost the entire time developing. The result is a much lower contrast negative than you would get otherwise. As you can imagine, if you were to agitate, say, every 10 seconds then the whole effect would be ruined. The big danger with this method is streaking and uneven development of the negative. If this is a problem then your only alternative is to agitate more often and put up with the slightly increased contrast. I hope this helps. -- Eric Lundblad
jer@peora.UUCP (J. Eric Roskos) (06/11/85)
I originally posted this reply to the person who wrote the original query,
but it came back as undeliverable. So...
I use the Technical Pan almost exclusively for B&W now; not too long ago,
I experimented with using conventional developers with it. They don't work
satisfactorily. Levels of luminance that fall on the linear portion of
the characteristic curve turn out looking fine, but the parts out at the
ends end up washed-out. The result looks like you simultaneously overexposed
and underexposed the photograph.
The Technidol works very well. I wish, though, that I could find where to
get the chemical required to mix your own... I posted a query in here about
a month ago, you'll recall; but no response at all. Technidol's not that
expensive, really, considering the improvement in quality.
--
Full-Name: J. Eric Roskos
UUCP: ..!{decvax,ucbvax,ihnp4}!vax135!petsd!peora!jer
US Mail: MS 795; Perkin-Elmer SDC;
2486 Sand Lake Road, Orlando, FL 32809-7642
"Erny vfgf qba'g hfr Xbqnpuebzr."mike@asgb.UUCP (06/12/85)
> >> Was there a note here recently about using HC-110 to develop > >> technical pan film? ... > > >I wouldn't be TOO hopeful here. Tech pan is such a high contrast film > >that you need developers specifically designed to produce low contrast > >results. > > I have had decent results with a dilution of HC-110 with tech pan. You ====== > can indeed get the low contrast characteristic from HC-110 if you spend > some time reading the data sheets. Technidol is still the best, but > HC-110 is also one of the recommended developers on the tech pan data > sheet. HC-110 is indeed one of the developers recommended on the tech pan data sheet, however at the dillution/times listed, it still produces a negative significantly more contrasty than technidol. I remember a PhotoGraphic article about developing tech pan with ( I think ) FG-7. I'll try to dredge out that article. Getting down to normal contrast ranges with HC-110 probably requires some testing. also... Maybe I'm getting too picky about wording here, but I thought the idea behind using tech pan was to get SUPERIOR results, not decent. Mike Rosenlof ihnp4!sabre!\ hplabs!sdcrdcf!-bmcg!asgb!mike { ihnp4, ucbvax, allegra }!sdcsvax!/ Burroughs Advanced Systems Group Boulder, Colorado