My first Zone System test

[jack_hui]

Dear all,

I am new to B&W field, and would like to perform a series of ZS test by myself. After I read several good books, I have come up with the following procedures;

Tools and material:
1) 3 film holders with 6 HP5+ films
2) extra 5 holder's slide. Each one of them has drilled a hole of 10mm, and each hole has a different location on each slide.
3) One light box (white light)
4) 8x10 camera with 300mm len
5) 1 deg. Spot light meter


Procedures:
1) setup the camera with the len, and set it to infinity.
2) Turn on the light box until the light is stable and use the spot meter to check the variation of the light is within 1/10 EV.
3) Put the light box close to the len, so that the gound glass can only show the "white light"
4) Meter the light box @ISO200 and reduce the reading by 5 stop, i.e. it would be Zone 0
5) replace the dark slide with the first "drilled hole slide", and shot once, then the "exposed hole" would be
Zone 0
6) Adjust the exposure by +1ev
7) Replace the dark slide with the second "Drilled hole slide", and shot once, and it would be Zone 1
8) Cont' the rest shots (from Zone 0 to Zone IX)
9) Shot all 6 film by doing the same step as above.
10) develop the 6 film by different time, read the density and plot the graph, and hopefully I can get my result.

Can anyone tell me, is there anything wrong with my
procedures???

Thanks a lot!

Jack
P.S. I am not an English speaking person, and hope you all
can understand what I meant above.

[aduncanson]

Since you have received no real answers, I will weigh in with my observation that your approach should get you the data you require, but that you will probably find that film is much less expensive than all of those dark slides that you plan to mutilate.

[Alan Curtis]

Jack
Since you are new to B&W I'm going to suggest that you invest in Bruce Barlow's CD book. It gives a very clear and simple way to do the zone system film testing you want and includes the neutral density filter that will help you determine all the basic steps you need to get started. I think the CD is $20.
Also there is a DVD by Richard Ritter on camera repair, it gives a great way to mark your film holders without drilling holes in the dark slides. you can find both at www.circleofthesunproductions.com

[venchka]

Hmmmmmmmmmmm...

Here are my thoughts and bear in mind:
1. I know nothing. Very possible.
2. I'm about to make the same test myself with Ilford HP5+.

1. You won't be photogrpahing light boxes. Set your camera up to photograph a real subject refelcting light. Use the light box to evenly light a grey card?
2. Stop down 4 stops to Zone 1. Your test is supposed to find the minimum exposure to produce Zone 1 (1 stop above base + fog) on the negative. It seems to me, and I am probably wrong, that closing down 5 stops to Zone 0 would be the same as base + fog.
3. Pull the darkslide out halfway. That way you will have an exposed half and an unexposed half of the negative. Cheaper and easier than drilling holes in dark slides. 8x10 dark slides are expensive.
4. Start the test at Box Speed (400) + 2/3 stop. Looking at my Weston Master V the progression would be:
650
500
400
320
250
200
Open +1/3 stop for each exposure, 6 in all. That should be enough to find "your" correct film speed for the film-developer-time-temperature used in the test.
5. Develop all sheets at the same time in the developer you will be using after the test. Use either the film makers time or the developer makers time for the test.
6. Evaluate to find Zone 1.

That's what I'm getting ready to do. Probably this afternoon before Hurricane Ike gets here.

1. Pick an evenly llluminated surface.
2. Six exposures in 1/3 stop increments from ASA 650 to ASA 200. OOPS! ISO.
3. Develop in Xtol 1:3 in a Jobo 3010 tank on a one way Beseler motor base at 30+ RPM. Time of 12 minutes 15 seconds at 68F or 20C from the German Xtol data sheet for rotary processing.
4. I'm planning to contact Richard Ritter and send the negatives to hime for evaluation.

Good luck!

[Darren Kruger]

3. Pull the darkslide out halfway. That way you will have an exposed half and an unexposed half of the negative. Cheaper and easier than drilling holes in dark slides. 8x10 dark slides are expensive.

that will work for the first exposure. but what about the second? How would you mask the part that you just exposed to light?

For testing 4x5 film in the past, I have used a darkslide that is mostly cut in half. Looks like a big L. It would produce two panoramic images on the same 4x5, with around 8mm of blank film between the image parts. It allows for two tests (images) per sheet plus an area to read the base fog in between.

Another option for testing film that doesn't involve cutting up a darkslide is using a Stouffer Step Wedge. There is a thread on APUG that describes one method for using it.

-Darren

[kev curry]

Jack there's a very simple and easy way of obtaining your Personal Film Speed and Development Time's in the free section of ''View Camera Magazine''. Its a great way of testing. It might be worth a read. It doesn't have to be complicated:-)


http://www.viewcamera.com/archives.html

kev

[venchka]

From the article quoted above:

Now, pull the darkslide out only half
way. You want to expose only half of the film and leave
the other have unexposed. After partially exposing this
sheet, do the samewith another sheet,

3 holders. 6 sheets of film. 6 half negatives exposed.

I based my plan of attack on Steve's article. However, I think my method of starting at ISO 650 through ISO 200 is easier for my old brain to understand than using percentages of the box speed.

After partially exposing this
sheet, do the samewith another sheet, but at a film speed
of 75% of the recommended exposure index. Now, do a
third sheet at a film speed of 50% of the manufacturer’s
recommendation. Now, do a fourth sheet with a speed
of125% of the manufacturer’s recommendation, and
then a fifth sheet with a speed of 150% of the manufacturer’s
recommendation. The sixth sheet can remain unexposed.

400 x 0.75 = 300 Not on my meter. Using 320 & 250 instead.
400 x 1.5 = 600 Not on my meter. Using 650 instead.

[jack_hui]

Dear all,

Thanks you very much for your kind comment, I will re-construct my test.


Jack

[jetcode]

I use a special card for calibrating exposure and development times or working ISO. I use something similar to the following:

http://www.colorhq.com/product-p/50103.htm

1) setup in desired light scenario.
2) meter the subject and determine target exposure
3) shoot 3 sheets at 3 different ISO's
4) develop each individually noting ISO and development time used
5) tweak development time according to exposure and intended dynamic range

the result is exposure/process time that is tuned to the light source and intended dynamic range for a particular film

[ElrodCod]

Jack,
Make it easy on yourself & get a copy of Fred Picker's book The Zone VI Workshop and follow the directions.