what kind of film?

Phillip Robinson phrobins at mail.usyd.edu.au
Sat Feb 22 22:14:08 EST 1997

Michael Fitch wrote:
> Our lab uses autoradoigraphy film to detect 32P and chemiluminescent
> signals. We've used several different kinds over the past few years, but
> we'd like to use a single kind for everything if possible. Does anyone
> know how different brands and types of film compare for use 32P and
> chemiluminescence? We'd also like to use the cheapest thing that will
> meet our needs (of course). We've used Kodak XAR and DuPont/NEN
> "Reflections" recently, and I've been promised a sample of Kodak Biomax
> MS (and I've tried to find out the difference between Biomax MS and
> Biomax MR). Comments on any of them are welcome, as are suggestions.

We have been playing with this question a lot lately and have come up
with the following from a mixture of exprience and "sales-talk" (mainly
the former, don't trust the latter much).  We have decided after 16
years of 32P autorads to go 100% with the new Kodak film BioMax Lite
(properly known as Biomax ML (Cat 178 9207 for 10x8 in) for both
autorads and ECL.  It is not the fastest film in the world, but is on a
clear base.  In fact it is supposed to be the old Xomat film emulsion
transferred onto a clear instead of grey plastic base.  Kodak push it
for ECL (for which it is great).  However, Kodak neglect to say that it
is great for 32P (I assume because they want you to use MS) but we now
use it to REPLACE XOmat.  It works with most screens (Lightning plus
etc), and gives a very nice picture due to the much clearer background.

MS seems to be a new emulsion, only sold on this clear base plastic.  It
comes in two types that we know about.  The difference between MS and MR
is simple, MS is faster since it is a double sided emulsion (like X Omat
and ML), while MR is single sided and slower - but giving slightly
sharper resolution.  (One doesn't use the latter with screens - this
normally makes little sense).  As advertised, MS is a faster film than
X-Omat (and ML, we find its about twice as fast), but clearly grainer
and more diffuse in our hands.  With a screen, it is indeed the fastest
film for 32P we have tried yet.  However, it is NOT very good for ECL,
since it fogs badly (too sensitive).  It worked fastest for us on their
special screen, but works well with lightning plus too.  We also notice
it seems to age very poorly in our cupboards OR coldroom and only lasts
a couple months for us before fogging up to badly.  Therefore we have
virtually stopped using it.  Does anyone else have similar fogging
problem with MS??

In summary, we find ML is the best "all-rounder", while MS is the
"fastest" for 32P autorads.  Hope our experiences help.  It took us a
long time to work this out!!

Phil					Sydney, Australia

More information about the Methods mailing list