First experience with Gigabit film

Some Dude wrote:

Donald you have a "WIP" website?

I'm guessing, since I don't know what "WIP" stands for, that I probably
don't -- please enlighten me!

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.

Some Dude wrote:

Donald you have a "WIP" website?

I'm guessing, since I don't know what "WIP" stands for, that I probably
don't -- please enlighten me!

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.

Work In Progress


On Wed, 14 Jul 2004 02:59:52 GMT, Donald Qualls
wrote:

Some Dude wrote:

Donald you have a "WIP" website?

I'm guessing, since I don't know what "WIP" stands for, that I probably
don't -- please enlighten me!

Cheers,
-sd
http://www.zoom.sh

Some Dude wrote:

Work In Progress


On Wed, 14 Jul 2004 02:59:52 GMT, Donald Qualls
wrote:


Some Dude wrote:


Donald you have a "WIP" website?

I'm guessing, since I don't know what "WIP" stands for, that I probably
don't -- please enlighten me!

Ah. Photographically, no. If you follow the links in my .sig below,
you can link from there to my main page, and thence to a number of other
pages about model rocketry (which I did intensively from 1996 until
2001, building more than forty models and recording literally hundreds
of launches -- at least one model was flown more than fifty times),
telescope making (with a little astrophotography thrown in), and a small
page on digital photography, which hasn't been updated in almost three
years.

Once I complete my upcoming move and get settled, I'll be able to get my
darkroom set up, set my machine shop back up, and get started making
stuff worth putting on pages to replace those old ones. Of course, I
need to find an economical place to host a relatively large storage and
bandwidth for photo viewing -- the two webspaces I have for my ISPs
total only 20 MB storage, with one explicitly limited to 650 MB per
month and the other likely to have a similar limitation; those numbers
pale pretty rapidly when you want to put up pictures bigger than a
couple hundred kB.

I do have a portfolio on photo.net, where recent work can be seen (and
even critiqued, if you're a registered user):

http://www.photo.net/photodb/member-...user_id=748533

These images are up to about a year old, including a few made when I
first picked up film photography again last summer.

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.

Do you know why Gigabit recommend a non hardening fixer? ......it seems to
go well with Teternal Superfix Plus at 1:20 in 3 min. But the film curled
after fixing.
Could this be caused by the hardening fixer?

Max

"Donald Qualls" skrev i en meddelelse
news:cBcIc.34553$WX.33961@attbi_s51...
MXP wrote:

Thank you for the link.
I will use 1 min. less in the developer next time I develop a Gigabit
film
and then see if it looks better.

If the negatives were thin, you'd need to either increase exposure (if
the shadows lack detail) or increase development (to increase contrast
and increase density in the highlights). Reducing development would
make them thinner still.

However: Gigabit film is a microfilm emulsion, and for pictorial
application those typically need to be developed to relative low
contrast. I've gotten good results with Kodak and Agfa microfilms with
extreme dilution or relatively short development in a low activity
developer (which is more or less what POTA and Technidol are --
developers with normal alkalinity but reduced level of developing agent,
to reduce activity and make low contrast development possible in a time
compatible with tank processing). But any attempt to develop to higher
contrast results in excess contrast instead -- what appears to happen is
that the film base is much clearer than we're used to, and a negative
that prints well will look very thin without the gray base color.

I recommend printing before you adjust development -- if the negatives
print well at normal contrast, it doesn't really matter how they look to
the eye.

It is written the fixer has to be
diluted
1+20 or something like that where normal is 1+3 to 1+9. Do you know the
reason for that?

Diluted fixer is recommended for some microfilm stocks because it makes
it easier to avoid overfixing. With ordinary films, overfixing by 2x or
even 10x the correct time (which is 2x to 3x the clearing time) has no
visible effect, but the extremely fine grain of microfilms can show
discernible bleaching in "film strength" fixer in as little as ten
minutes. Very dilute fixer, combined with a clearing time test and
fixing for no more than 3x clearing time, will allow minimum fixing with
a film that would normally clear in 30 seconds in fresh rapid fixer at
film strength -- and thus avoid bleaching away shadow details.

The Efke ISO 25.....has it about same grain size as the Gigabit?
Do you use normal developer for the Efke?

Not even close. Efke R25 is a pretty ordinary ISO 25 film, other than
its reduced red response; it's very fine compared to an ISO 100 film,
especially in a super fine grain developer like A49 or Microdol-X
(which, however, would reduce the effective speed to about EI 12), but
it's still nowhere near as fine, or capable of the kind of resolution as
microfilm emulsions like that on Gigabit film. Microfilms gain fineness
and resolution because they have only a single grain size, instead of a
range of grain sizes or even multiple emulsion layers with different
grain size ranges in conventional films. This makes them tricky to
develop for continuous tone, because different grain sizes make for
different sensitivity levels from grain to grain and automatically
produce a stochastic stipple that blends into a smooth continous tone if
not enlarged too much -- with microfilm, one must instead develop in a
manner that gradates how much silver is developed from exposed halide
crystals, based on how much light they received; compared to ordinary
film that can be over- or under-developed by a large factor and still
produce printable negatives, microfilm in pictorial use has little
tolerance for changes in development -- because overdevelopment tends to
fully develop too many halide grains and lead to the "black or white"
look of document films (i.e. the film reverts to its design contrast),
while underdevelopment (relative to pictorial use) gives a huge loss of
speed, which is already low in pictorial use.

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.

MXP wrote:

Do you know why Gigabit recommend a non hardening fixer? ......it seems to
go well with Teternal Superfix Plus at 1:20 in 3 min. But the film curled
after fixing.
Could this be caused by the hardening fixer?

I don't know specific to Gigabit, but most films now carry a
recommendation for non-hardening fixer -- emulsions are hard enough now
not to need additional hardening for scratch prevention, and the harder
the emulsion, the longer it takes to wash (which can actually increase
the risk of damage, since the film will be wet longer).

Curling usually means that the film has little or no gelatin back
coating -- again, what one might expect from a microfilm, whose
resolution and archival properties are more important than its handling.
With a back coat, film that's wound on a spool and gets the least bit
damp will ferrotype -- layers stick together, with the gelatin acting as
glue. This is (very slightly) more recoverable if there isn't a well
subbed gelatin layer already present on both surfaces...

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.

"Donald Qualls" skrev i en meddelelse
news:d5HJc.101298$Oq2.76003@attbi_s52...
MXP wrote:

Do you know why Gigabit recommend a non hardening fixer? ......it seems
to
go well with Teternal Superfix Plus at 1:20 in 3 min. But the film
curled
after fixing.
Could this be caused by the hardening fixer?

I don't know specific to Gigabit, but most films now carry a
recommendation for non-hardening fixer -- emulsions are hard enough now
not to need additional hardening for scratch prevention, and the harder
the emulsion, the longer it takes to wash (which can actually increase
the risk of damage, since the film will be wet longer).

Curling usually means that the film has little or no gelatin back
coating -- again, what one might expect from a microfilm, whose
resolution and archival properties are more important than its handling.
With a back coat, film that's wound on a spool and gets the least bit
damp will ferrotype -- layers stick together, with the gelatin acting as
glue. This is (very slightly) more recoverable if there isn't a well
subbed gelatin layer already present on both surfaces...

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.


OK.
I have been happy so far with the Teternal Superfix Plus. And it seem to
work well for
Gigabit film also.

I have just got some new Gigabit films. This time with description in
english. They seems to
be aware of the curling problem and suggested to put the film "opposite" in
the develoment
spiral and let it be there for 24 hours. I will do this next time.
The description for development, agitaion and fixing is also much better.
The only thing is that they only writes about 20 sec. fixing in normal film
strength fixer. In the old description they recommented to dilute thinner to
reach a fixing time of 2-3 min.

Max

MXP wrote:

The only thing is that they only writes about 20 sec. fixing in normal film
strength fixer. In the old description they recommented to dilute thinner to
reach a fixing time of 2-3 min.

The concern with long stays in full strength film fixer is that it can
bleach the image. This isn't usually a concern with conventional films;
most ISO 100 films won't show visible bleaching (though it is measurable
with a densitometer) after soaking for 24 hours in rapid fixer. I have
bleached with fixer, using film strength acidified with additional
acetic acid (one ounce stop bath concentrate in eight ounces of working
solution fixer); it took about an hour in this more active solution to
show visible bleaching in Kodachrome developed with B&W chemistry. With
the extremely fine grain of microfilms, however, there's a real
possibility of significantly degrading the image by overfixing -- even
more frightening, since all the grains are the *same* size, you might
not really notice bleaching (if you take the lid off to look at your
film in the fix, like a lot of folks do) until, fairly suddenly, the
film goes from very slightly thin to completely clear.

I don't know that image bleaching with fixer would be this dramatic,
even with microfilm -- but degradation from overfixing is real, and much
more a problem with the very small grain of microfilm stock. I've used
rapid fixer at 1/5 of normal film strength to get fixing time around 6
minutes on Tri-X in an monobath experiment -- this was used one-shot, of
course, but no sign of problems. What I'd suggest is to make up a
special working solution of fixer you use only for Gigabit, diluted as
they suggest; do a clearing test with a scrap of Gigabit film in this
fixer, and then fix for twice the clearing time as you would with any
fixer -- and don't over fix. Keep careful track of capacity; if diluted
1:2 relative to normal film strength, this fixer will have a capacity
1/3 as great per liter (instead of 24 films in a liter of Ilford, as an
example, you'd get only 8 films in a liter after dilution 1:2 with water
-- one "film" being 80 square inches, a 135-36, 120 roll, or 8x10
equivalent of sheet film).

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.

"Donald Qualls" skrev i en meddelelse
news:1G1Kc.109280$Oq2.9664@attbi_s52...
MXP wrote:

The only thing is that they only writes about 20 sec. fixing in normal
film
strength fixer. In the old description they recommented to dilute
thinner to
reach a fixing time of 2-3 min.

The concern with long stays in full strength film fixer is that it can
bleach the image. This isn't usually a concern with conventional films;
most ISO 100 films won't show visible bleaching (though it is measurable
with a densitometer) after soaking for 24 hours in rapid fixer. I have
bleached with fixer, using film strength acidified with additional
acetic acid (one ounce stop bath concentrate in eight ounces of working
solution fixer); it took about an hour in this more active solution to
show visible bleaching in Kodachrome developed with B&W chemistry. With
the extremely fine grain of microfilms, however, there's a real
possibility of significantly degrading the image by overfixing -- even
more frightening, since all the grains are the *same* size, you might
not really notice bleaching (if you take the lid off to look at your
film in the fix, like a lot of folks do) until, fairly suddenly, the
film goes from very slightly thin to completely clear.

I don't know that image bleaching with fixer would be this dramatic,
even with microfilm -- but degradation from overfixing is real, and much
more a problem with the very small grain of microfilm stock. I've used
rapid fixer at 1/5 of normal film strength to get fixing time around 6
minutes on Tri-X in an monobath experiment -- this was used one-shot, of
course, but no sign of problems. What I'd suggest is to make up a
special working solution of fixer you use only for Gigabit, diluted as
they suggest; do a clearing test with a scrap of Gigabit film in this
fixer, and then fix for twice the clearing time as you would with any
fixer -- and don't over fix. Keep careful track of capacity; if diluted
1:2 relative to normal film strength, this fixer will have a capacity
1/3 as great per liter (instead of 24 films in a liter of Ilford, as an
example, you'd get only 8 films in a liter after dilution 1:2 with water
-- one "film" being 80 square inches, a 135-36, 120 roll, or 8x10
equivalent of sheet film).

--
I may be a scwewy wabbit, but I'm not going to Alcatwaz!
-- E. J. Fudd, 1954

Donald Qualls, aka The Silent Observer
Lathe Building Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Speedway 7x12 Lathe Pages http://silent1.home.netcom.com/my7x12.htm

Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.


I will make a clearing time experiment with an extra diluted fixer and try
to reach 2-3 min.
of fix time. When I develop film I only use the developer and fixer once.
Thank you for the answer.

Max