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View Full Version : calibration: film speed, density, development for Plat/Palladium negs



J.Davie-S.
11-Jan-2011, 22:39
Hello. I've been doing a lot of reading on testing for ones own effective film speed but in spite of my research i'm still a little confused about the process. Most of what I've read is for negative enlargement for silver printing but I'm trying to gain some control of my materials for Platinum/Palladium printing. I've consulted the following so far:

Arentz, Platinum printing
Adams, The negative
Schafer, advanced techniques in photo...

I don't have access to a densitomiter. I do have the proper step wedges to shoot at zone 10. All the steps that I've found that follow are for enlarging negatives to find density and development times.

Can anyone share some experience on this?

Joseph

D. Bryant
12-Jan-2011, 04:50
Hello. I've been doing a lot of reading on testing for ones own effective film speed but in spite of my research i'm still a little confused about the process. Most of what I've read is for negative enlargement for silver printing but I'm trying to gain some control of my materials for Platinum/Palladium printing. I've consulted the following so far:

Arentz, Platinum printing
Adams, The negative
Schafer, advanced techniques in photo...

I don't have access to a densitomiter. I do have the proper step wedges to shoot at zone 10. All the steps that I've found that follow are for enlarging negatives to find density and development times.

Can anyone share some experience on this?

Joseph

Joseph,

You need to fill us in with more details about your experience printing palladium.

Have you made any palladium prints?

Do you have a Stouffers step tablet?

What materials (paper, print developer, etc) are you using? Consider purchasing a kit from Bostick & Sullivan. Winter time isn't the best time to do palladium printing unless you have very good humidity control. Low RH is the foe of good palladium prints though there are work arounds.

If possible just take a workshop to get jump started. There is a lot of information (good and not so good) available on the internet. Technically Arentz is all you need though I realize his writing can be off putting.

Be prepared to make a time and money committment, at least to the extent to determine if you really enjoy the process.

Ken Lee
12-Jan-2011, 05:43
If you use Pyro developer, your negatives will have equivalent density under UV light (required for Pt/Pd) and visible light (required for silver printing or scanning).

It's an old trick, but a very valuable one if you want your negatives to be usable for both methods.

Jim Noel
12-Jan-2011, 09:51
If you don't want to get involved with pyro developers,which is true of a lot of people you have other recourses which will get you in the ball park w/o a lot of testing..
1. double your development time with your normal developer.
2. double the strength of your developer and use your normal time.
3. If you happen to use HC-110 dilution"B" (1+7 from stock), switch to dilution "A" (1+4 from stock) and use your normal time.

If you also reduce your exposure about 1/3 stop your shadows will have less density and your printing times will be reasonable.

ic-racer
12-Jan-2011, 10:16
I don't have access to a densitomiter.

For the film speed test, it is not too bad without a densitometer. Realize that the 0.1 log is the same as one-third of a stop. So, if you put your zone-I exposed frame over your meter and if it drops the exposure reading by one-third of a stop, then you zone-I frame was exposed at the correct expousre index.

For development, I'd just do as suggested above by Jim and make further changes to negative development depending on how the prints look. Densitometery readings are only going to get you in the ballpark anyway if you are starting from scratch and going to use someone elses numbers. I'd undertake sensitometery and densitometry after you have determined the development needed to make a good print, so you can repeat your good results in future situations.

J.Davie-S.
12-Jan-2011, 13:35
Wow! Thanks you all for your willingness to help and the responses to my question.

I have printed pl/pd before. I'm printing on BeinFang, Cot-22, or arches platinne. I know that changing papers changes everything so for the sake of testing I'll stick with one of these. My goal is to get a better understanding of my process and gain control of my materials so that I can deliberately make better negatives for printing Pt/Pd.

I do have a calibrated Stouffer step tablet and a 4x5 step wedge. I'm shooting with a ToyoG 4x5 on trix Pan 320 and developing in D-76.

I would like to learn how to rate my own film for an effective speed but I'm not a math wiz and log(arithm) are alluding me so I need to get some tutoring and do my homework on that.

I would love to take a workshop but I havn't been able to find one that offers the technical information that I need for making negatives. What I've seen seems to be mostly about printing. Can anyone suggest. I'm live in NY City but I'm willing to travel.

I know that this isn't the best season for printing because of the low relative humidity that's why now seems to be a good time to work on in camera negatives. I've been working with doubled development times but call me old fashioned, I really want to be more deliberate about my process, have a thorough understanding of exactly how the process works and know what I'm doing. For that reason I want to start with the basics prior to using Pyro.

I just found an article by Steve Simmons on this that I'm going to review. Perhaps that will help. Dick's book is full of information but the parts that I need the most seem to go over my head.

Thanks again all. Any other tips and advice are greatly appreciated.

Joseph

Ken Lee
12-Jan-2011, 15:05
I would love to take a workshop but I havn't been able to find one that offers the technical information that I need for making negatives. What I've seen seems to be mostly about printing. Can anyone suggest. I'm live in NY City but I'm willing to travel.

Carl Weese (http://www.carlweese.com) lives in Connecticut, around 2-3 hours north of NYC if you have a car. He's one of the experts in the field.

He teaches workshops and does in-person coaching. I took a 1-day personal training with him in Pt/Pd. It was invaluable and worth every penny. He's a great fellow and a great teacher. His knowledge is very substantial. Did I mention that he really knows the subject ?

keith schreiber
12-Jan-2011, 16:34
In addition to Carl, here are a few more suggestions for possible workshop teachers:

Kerik Kouklis (http://www.kerik.com/new/)
Clay Harmon (http://www.clayharmon.com/blog/)
Tillman Crane (http://www.tillmancrane.com/index.php)

Many, if not most, group workshops these days seem to be geared towards working with digital negatives. All of those mentioned above should be able to help you learn to make proper in-camera negatives for Pt/Pd.

~ Keith

J.Davie-S.
12-Jan-2011, 17:00
Again, thanks everyone.

Ken and Keith, I will give Carl a call and set something up. I've visited his site but it never accrued to me to inquire about instruction. Thanks. The Simmons article that I mentioned is pretty straight forward. I think that will also help.

Best,
Joseph

D. Bryant
12-Jan-2011, 18:27
I would love to take a workshop but I havn't been able to find one that offers the technical information that I need for making negatives. What I've seen seems to be mostly about printing. Can anyone suggest. I'm live in NY City but I'm willing to travel.

Carl Weese (http://www.carlweese.com) lives in Connecticut, around 2-3 hours north of NYC if you have a car. He's one of the experts in the field.

He teaches workshops and does in-person coaching. I took a 1-day personal training with him in Pt/Pd. It was invaluable and worth every penny. He's a great fellow and a great teacher. His knowledge is very substantial. Did I mention that he really knows the subject ?

I agree with Ken, Carl Weese is a good choice for a one on one workshop for large format negs based on your locale. Also keep in mind that http://www.projectbasho.org/ in Philli offers workshops and they maybe able to set up a one on one workshop there. Kerik also does workshops there occasionally.

Also Sal Lopes is located right in NYC and maybe able to offer a workshop to you:

http://www.sallopes.com/

And I will also mention Keith Schreiber is a very good palladium artist and maybe a good choice for a one on one workshop since he served as Dick Arentz's assistant for several years.

http://web.me.com/j.k.schreiber/JKSchreiber/Welcome.html

Good luck,

Don Bryant

keith schreiber
16-Jan-2011, 14:36
Thanks Don.
:o

J.Davie-S.
17-Jan-2011, 14:31
All-

With regard to the step tablet and zone x in my earlier post, I was referring to information from J.P. Schaefer's book Basic Techniques for Photography. He suggests taping a step tablet diagonally across a sheet of 4x5 film and expose it at zone x while the camera is focused at infinity on an evenly lit surface. (Can a 4x5 step tablet be used also?) He then goes on to use a densitometer to measure the density of each step. He does give an alternative if a densitometer isn't available but he's using and enlarger and I'm not sure how to adapt his method to contact printing.

Another method I found is by Steve Simmons. He details the following steps to find:

print test exposure time

personal film speed

personal normal development time

Also, this is similar to what Adams’ suggests in his book The Negative except that the following dictates the adjustments to be made in percentages when executing the following tests. No step tablet is used.

1.Create a series of (two) test strips using an unexposed developed negative printed just to maximum black to find the proper print time for the respective film and paper combination.
2.Shoot five (he suggests that the dark slide cover half leaving an unexposed section) exposures of an evenly lit surface at the manufacturers ASA. First exposure metered for zone 1 then the remaining exposures shot a 75%, then 50%, then 125% and finally 150% of the manufacturers film speed.
3.Using the print time found in step one print tests with exact same variables used previously. Exposure that yields the tone for zone 1 (just lighter then max black) is EFS (effective film speed). This determines the bottom of the exposure scale.
4.To find the top of the scale shoot six sheets of film at the zone that’s designated as the top of the scale (i.e. 7,8,9...). Develop the first sheet at manufacturers recommendations, then each following sheet at 60%, then 80%, then 110%, the 120%, and finally 130% of the recommended time. Print these tests again using the previously found proof time to find the negative that yields a tone just darker then paper white. When this negative is found its corresponding development time defines the top of your exposure scale and development time to reach that zone.

Although a lot of film is necessary to accomplish the above process, it seems relatively straightforward. I still have a have a few questions regarding the process.

1. When figuring reduced and expanded development times mathematically using percentages, I get development times that I can’t define in terms of seconds. For example: 60% of an 8 min development time (recommended by the manufacturer) equals 4.8. An 80%= 6.4, 110%= 8.8, 120%= 9.6, and 130%= 10.4. How important is it that these fractions of minutes be accurate? Should a number like 4.8, which is close to 4.75 become 4 minutes and 45 seconds?
2. I’m also curious where the original percentages (60, 80, 110, 120, 130%) of the recommended development time come from? How do the progression of these numbers relate to each other? For example how does 60 become 80 becomes 110...?
Finally, Finally, with regard to expanded density range necessary for the platinum palladium process, what zone should one shoot for when trying to establish the top of the film scale as described in step 4 above.

Best,
Joseph

Jan Pietrzak
17-Jan-2011, 15:17
Joseph,

I guess that I have to put my hat in the ring. After a short vacation from teaching workshops and classes and also moving. I will be doing a workshop in Santa Fe, New Mexico at the end of September. Pt/Pd 101 and Pt/Pd 102, two weekends with time in-be-tween. Students can take the first part or the second part, or both parts. We will start with the basics in part one and do advanced stuff in part two.

The group will be small and the days will be long. And we will have time to look at work and make some great prints.

Jan Pietrzak

J.Davie-S.
19-Jan-2011, 11:39
Jan,

Thanks for the info. Please post details about your workshop or a link when you can.

thanks.

Jan Pietrzak
19-Jan-2011, 15:59
Joseph,

The process is evolving, you can look at the Carbon Forum at Bostick and Sullivan, and soon to be added to the Freestyle Calendar of events. I will also pm you what I have.
Thanks for asking

Jan Pietrzak

hmf
22-Jan-2011, 04:19
Tillman Crane offers a 4 day Pt/Pd workshop in July, at Peter's Valley in New Jersey. I took it a couple of years ago and highly recommend it. Tillman is a great teacher.