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Re: [APML] More bad film news
Hi Jason
I start by going through the published film data from the manufacturers
until I find a film which has extended red response. So far I have found
SFX-200, Delta 400, Delta 3200, Fortepan 200, Fortepan 400, FomoPan 400.
I have been restricting myself to films which are available without too
much grief in North America. There is one additional film that I will be
testing, it probably doesn't have the extended red that we want, but it
may prove to be an excellent very low grain film for reflection nebulae
and other targets in the blue green spectrum.
>From there I have been taking the film out of the box and shooting a few
frames with a 50mm lens stopped down to f/2.8. I generally shoot two
frames unfiltered for five and ten minutes followed by two frames with a
lumicon HA for 10 and twenty (when I am lucky) minutes.
This is just to see how the film is straight. With the SFX I extended my
testing but more on that later.
I snip off the exposed film and develop it in HC-110 for the recommended
amount of time and then have a look at the results after scanning.
So far I have found:
SFX-200 Not red dead, but it wants full light to have any effect on the
film. Extended testing included pre-flashing, vacuum baking, and a
combination of the two. There was some improvement but still NFG for AP
work. No hypering done yet. The film is a moisture sponge and degrades
very quickly at low light levels as it absorbs moisture.
Delta 400 With a one stop push it shows some promise straight out of the
box, apparently it has nice characteristics for daylight shooting when
processed at 200ASA. So when the gas arrives it will get a shot at
hypering.
When I go to hyper my first roll of TP I'll toss in a few short rolls of
the above two films (and posibly the fortepan if it arrives in time) and
then snip off a piece to process it see the background fog levels. I'll
then shoot a few frames with the previous mentioned procedure.
If any of those show promise I'll then try a few different hypering
times to try to get closer to the correct amount of hypering for that
film.
When I have some films worth testing I'll then courrier some hypered
samples to another list member who has offered to do a more detailed
spectral and reciprocity analysis of the film.
Not an overly scientific approach but it will hopefully produce some
results worth sharing.
In the meantime drop a letter to the people at Kodak and let them know
how you feel about them dropping TP from their film lineup.
George Anderson
Montreal Canada
Clear skies and good health
"Lane, Jason R" wrote:
>
> Hi George,
>
> If folks are wanting to help out testing films, do you have a standard procedure to follow in order to obtain objective results?
>
> -Jason
>
> -----Original Message-----
> From: astro-photo-bounces@seds.org
> [mailto:astro-photo-bounces@seds.org]On Behalf Of George Anderson
> Sent: Monday, August 30, 2004 7:28 PM
> To: Discussion of Film Astrophotography
> Subject: Re: [APML] More bad film news
>
> Ray
>
> I don't believe that films from any of these companies have undergone
> any true testing if any at all.
> Up until now there has been no true need as hypered Tech Pan has been
> the only film for fine detail B&W (although I could be wrong).
> What needs to be done is some true testing on the available B&W films
> much like Don Westergren and Robert Reeves did with colour.
> And we shouldn't just stop if a film doesn't work out of the box, we
> should test these films for hypering as well.
> I realize that I have been throwing the "we" around, but for any people
> interested in shooting B&W film after their stock of TP runs it should
> be a group endevour.
> In a two weeks or less I should have my tank of hypering gas at which
> point I will start hypering TP as well as drop some film chips in the
> tank to see if there is any change in background density in the 100hours
> that it will take my first test roll of TP to hopefully hyper. I
> presently have three film types to test and a line on a possible fourth.
> It may all pan out to zilch but the only way to find out is to test.
> The film types that Joe mentions are all easily found by a quick google
> search.
> Forte is available from the people who make Omega enlargers and from
> Eight Elm in Toronto. I have two rolls on order via a sister.
> Bergger is avaiulable from Bergger.
> MACO can be found at fine photographic shops, the type of places who
> stock 4 by 5 and 8 by 10 film plates as well as view cameras.
> There is also ADOX (Bluefire Police film in the USA) which is
> re-packaged microfilm with a special developer. It probably starts to
> roll off around 640nm, but it may fill in some gaps at other wavelengths
> where other films are weaker. The lack of grain is stunning.
> There is also Fomo who have an extended red film, which they openly
> admit suffers from reciprocity (didn't we have a treaty on that) but may
> "heal itself" with hypering.
>
> George Anderson
> Montreal Canada
>
> Clear skies and good health
>
> MACO, Forte, Bergger, Elk
>
> Ray Butler wrote:
> >
> > > growth of companies like MACO, Forte, Bergger, Elke and others -all
> > > too happy to jump in and fill the gap.
> >
> > But Joe, do any of these other companies make anything of use for
> > astrophotography? Have you tried their products, how good are they, and
> > where can you get them online? I'm sure many other APMLers would be
> > interested if you could provide us with some details.
> >
> > Ray
> >
> > --
> > Dr. Ray Butler (ray.butler@nuigalway.ie || ray@physics.nuigalway.ie)
> > Lecturer, Dept. of Physics || Computational Astrophysics Laboratory
> > National University of Ireland, Galway, University Road, Galway, Ireland.
> > Tel: +353-91-524411 ext. 3788 FAX: +353-91-525700
> >
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