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Re: [APML] Films responding to Ha, Hb, OIII
Ray, Canadian slang is consistent with American slang: bust is bad. So, for star trails it was a
very poor performer.
Stuart
----- Original Message -----
From: "Ray Butler" <ray.butler@nuigalway.ie>
To: "Discussion of Film Astrophotography" <astro-photo@seds.org>
Sent: Wednesday, October 13, 2004 11:07 AM
Subject: Re: [APML] Films responding to Ha, Hb, OIII
>
> Stuart,
>
> > Ray, this is very interesting to me. I recently bought 3 rolls of Kodak Chromogenic film - I
was
> > really pleased with how it performed in daylight and the C41 processing was a big bonus (I have
put
> > away my darkroom toys a long time ago). I tried it for star trails and it was a bust.
>
> Sorry: in American slang, does "a bust" mean a good or a bad result? I'm
> wondering, since "Hollywood, or bust" means "failure" whereas the
> similar term "having a blast" means "absolutely great"! It's not a term
> which has crossed the pond yet...
>
> > How sure are you that it will work for long exposure?
>
> I based this on Michael Covington's
> http://www.covingtoninnovations.com/astro/updates.html
> and
> http://www.covingtoninnovations.com/astro/films.html
> - which was "Revised 2003 October 24", so it should still be applicable;
> and on Patrick Freeman's
> http://www.geocities.com/freeman_patrick/astro_film_tests.html
> - whose conclusions (on the chromogenic films) I don't at all agree
> with. What he calls "saturated" I call "actually picking up lots of
> light and having the lowest reciprocity failure" ! To me, T400CN clearly
> comes out best of the lot (and somewhat better than the identical
> pairing of Portra B&W/Select B&W+), although to him it was the worst.
> And he reckons the XP2 Super was best, whereas to me it is clearly the
> least sensitive. So we take polar opposite views, based on these images.
> Anyone else care to comment?
>
> Ray
>
> > I think it would be great if there were a C41 compatible
> > B&W film.
> >
> > Stuart
> > ----- Original Message -----
> > From: "Ray Butler" <ray.butler@nuigalway.ie>
> > To: "Michael Barlow" <mikeba@rochester.rr.com>; "Discussion of Film Astrophotography"
> > <astro-photo@seds.org>
> > Sent: Tuesday, October 12, 2004 2:34 PM
> > Subject: Re: [APML] Films responding to Ha, Hb, OIII
> >
> >
> >
> >>And welcome from me too, Michael.
> >>
> >>You might also consider that since most colour print films are pretty
> >>dead to H-alpha, and poor enough in the blue-green region of H-beta and
> >>OIII, another alternative with a nebula filter is to use black and white
> >>film. This will perform really well on H-beta and OIII because it
> >>doesn't have the "falling between two stools" sensitivity problem that
> >>colour films (both prints + slides) have in this part of the spectrum,
> >>where their blue and green curves dip and cross over each other.
> >>
> >>There is a tradeoff, which is that you can't expect to pick up much or
> >>any H-alpha (unless you use some hypered Tech Pan, while it's still
> >>available). But for the filtered H-beta->OIII region (which is so narrow
> >>that a monochrome film is most appropriate anyway), B&W is ideal.
> >>
> >>And if you use a C41-process "chromogenic" B&W film, you can have your
> >>film processed anywhere that develops colour print film. Kodak TC400N is
> >>probably the best choice since it has extremely good reciprocity
> >>characteristics, according to Michael Covington's tests. Apparently it
> >>is now renamed Portra B&W or Kodak B&W. As always, check the film's
> >>spectral sensitivity curves on the spec sheets first. Here are the Kodak
> >>B&W specs (which look fine for H-beta->OIII):
> >>http://www.kodak.com/global/en/consumer/products/techInfo/f15/f15.shtml
> >>
> >>Ray "testing this film soon" Butler
> >>
> >>
> >>Michael Barlow wrote:
> >>
> >>
> >>>Hey gang, I'm new to the list,
> >>>
> >>> I've been photographing nearly two years but have never got in to the
> >>>technical side of it. All I've been doing is grabbing film off the shelf
> >>>(color print film) at the local grocery store and department stores for
> >>>Lunar, Planetary, and white light Solar through my 8" SCT. Just the last
> >>>couple weeks I've been grabbing shots of M31, M45, and snapping away at what
> >>>ever else I happen to see and wanted to step in to filtered photo's such as
> >>>Ha, Hb, OIII, and ect... I just bought a Meade #911 Nebular filter for the
> >>>SCT and just learned that most films have been reformatted to virtually
> >>>eliminate responses from Ha but haven't heard anything about the other two,
> >>>Hb, OIII. For the beginner in the filtered end of photographing in one or
> >>>all the above frequencies, Is there a cheap 35mm film that responds well
> >>>enough to learn from, color or B/W? I.E. Until I get my feet wet I'd rather
> >>>not buy expensive Hypered film or anything that costs over $5 US per roll.
> >>>
> >>>Michael A. Barlow
> >>>
> >>>_______________________________________________
> >>>Astro-Photo mailing list
> >>>Astro-Photo@seds.org
> >>>http://seds.org/mailman/listinfo/astro-photo
> >>
> >>--
> >>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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> >>http://seds.org/mailman/listinfo/astro-photo
> >>
> >
> >
> > _______________________________________________
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>
> --
> 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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