[pinhole-discussion] silver, copper and fixer deposits

2002-02-12 Thread eric nelson
Hello all,

Is is possible to use copper scraps to plate out silver from spent fixer?

There seems to be a mild attack on the copper if it is placed into spent fixer.
I am almost tempted to try copper plate etching for intaglio printing plates
using the fixer as a mordent. 

I am have held off due to the potential of other by-products... my knowledge
of chemistry is really rusty.

Is there anyone on the list with chemistry hints, or a resource book that can
steer me in the right direction. I thank you in advance.

mr. nelson
marshfield, wi 54449



[pinhole-discussion] keeping temperatures up in tube processing

2001-07-18 Thread eric nelson
An old sage from a camera club dropped this pearl of wisdom for keeping  his
solution temperatures constant. He placed desk  lamps with big bulbs shining
onto the rotating tube of his cibachrome tubes. It seems like an excellent idea.
His cibas were fantastic.


eric nelson, marshfield, wi usa



[pinhole-discussion] Re: lesson plans for students

2001-04-10 Thread eric nelson
Hello! Deborah, William, and all!

I can speak from experience. Grade six is fun to do pinhole photography with.

I like to break the unit into many parts to get a bigger bang for the
set-up. I first start with a what is looking lesson. Where the students
look through old master work paintings.

For example:
Jan Vermeer of Delft (1632-1675) is thought to have used a camera obsura
for his paintings. If you have not looked at any of his paintings i urge
you to do so. There is great artistry in his selected focus. There are
indications of circles of confusion in his works and selective soft focus
in his works. Delft was an early center for lens making.


Compostional studies are the next topic after the viewing historical
paintings and photographs. After studing the mechanics of how others see I
have the students refine their own compostional process. We use viewfinders
to select a portion of an all ready completed artwork. This is good time to
refine their eye. Particular attention can be paid to the selected area's
location in relation to the elements around it. This is often done in the
classroom with close-ups of other masterworks. The isolated abstract
element is appealing to them at this age level. - A large crowd shot is fun
to do like WeeGee's-sp? Famous shot of Coney Island. (sorry I don't have
my samples here today for titles and spelling)

The students finish their sketchs from the viewfinder exercise and then
begin to move the viewfinder up to make a sketch of thier own compostion
of the room. Wide angle and telephoto can be introduced at this time. Wide
angle close to eye telephoto far from eye.

I introduce cameras by simple medical illustrations showing how the eye
gathers an image. I use resource materials from old books to find these
line drawings. The camera obsura drawings found in the pinhole journal are
also excellent examples showing camera image formation. I convert my
classroom into a camera obsura by blocking the windows and placing a hefty
lens from an old spy plane in the window boards. The lights are turned
-off. Spooky!! THe image(of the playground) is caught onto a sheet of
frosted mylar, different aperatures are shown giving depth of field. I also
have built an adaptor to hold other lenses like my pinhole or zone plate
lenses.

We turn on red light and set up an exposure on darkroom paper from the
glass lens. A student holds a cardboard shutter to the lens. I process the
darkroom paper with chemistry in the room. The suprise is awesome. White
lights on and we study the picture! Operation of pinhole cameras are then
demonstrated and performed. Polaroid cameras are quickies and an the 4X5
ortho plywood cameras are slow.

Then outside to make a few 4X5 ortho shots. These can be a group shot in a
circle-or-off in pairs (depending on the group). THe kids process their own
film in the classroom. This year i plan on cyanotype contact prints after
the negatives dry. This is good because then the positive/negative steps
can demonstrated under regular light. I follow their own cyanotype image
making with a review of the steps they took. And follow with the historical
steps in photographic discoveries: daguerreotypes, salt prints,
cyanotype, ccd,cmos.

I bring in my pictures and historic artifacts like a tintypes or
daguerrotype to illustrate the history part of the talk.

Each class (about 27 kids) is a different group of individuals and almost
always some modifications are needed. I refrain from having the students
make a camera. This is because i have scheduling time constraints. Only an
hour a class. And there is no break between my next group of younger art
students.

Also, due to the wide diversity of students in the public schools i keep
the lessons simple and encourage an expressive eye. Previously, i had a
group make their own cameras but i learned of the trouble in shooting many
focal lengths and shapes of film etc. So, I built 30+ plywood cameras that
take 4X5 film holders. (I bought my holders from a spot in La Crosse
Wiscosin. Old time photostudios or camera shops have them in their back
room or basement it never hurts just to ask. I got mine for 5$ a piece!)

I have some images of cameras and student works at my school's website:

http://marshfield.k12.wi.us/art/elementary/pin.htm


And a lot more about the chemistry and steps that i use for processing on:

http://marshfield.k12.wi.us/art/cameramake.html

A fellow art instructor in the area used the above for her art challenge
(advanced) kids in high school. The students made thier own cameras and
produced pinhole images earlier this year. I'd like to do a pinhole image
swap next year or this year with my students and another group of students.

Best wishes and sorry this is so long.
Please let me know how i can improve my pages or the information on them.

Good Luck!
eric nelson
artist educator
marshfield public schools







[pinhole-discussion] really big pinhole camera.

2001-01-26 Thread eric nelson
bill,

I have made a 20X24 pinhole camera. My protoype was made of, black foam
core weather stripping, and gaffer's tape. It was fun to use but blew
around quite badly. I fould an old plate holder for a graphic arts camera
and the camera attached to it. It was super till it got soaked in a sudden
spring storm.

I wanted a more durable and stable camera to replace the soggy box so i
used pine and thin plywood. I totally over built the thing. Alone it was
heavy but with the wooden holder it weighs a ton. With a friend i can move
it about fine. It's fixed outer dimensions led to the inclusion of door
handles. I went with a fixed box design because i did not want to buy or
make a bellows.

Boy if i would have only placed all the pieces on the scale first it would
have allowed me a chance to re=design the camera before it was glued
screwed and assembled.

Please keep us informed of your discoveries as you build this challenging
project camera.

eric nelson
marshfield wisconsin 54449