If you are a traditional black and white photographer then you absolutely must determine your personal EI (exposure index) rating for your film and the SCT (standard contact printing time) which effectively produces your Proper Proof. I am not certain but I think Fred Picker actually coined the phrase so hats off to Fred and I hope he is resting in peace. Fred passed away on April 3, 2002 at the age of 75.
In this article I will provide the background of why the Proper Proof is important and why you should test and establish your SCT for your specific environment (i.e., film, developer and paper combinations). In the photo above I am in the process of establishing SCT for different papers. I only use two papers but I use them in RC and in Fiber making a total of four papers. For my fine art prints I only use fiber paper and for personal use or non-archival work I use RC paper.
There are actually several components that ultimately all fit together to enable a film based black and white photographer produce the highest quality negatives and ultimately fine prints. In this article I will walk you through how to determine your SCT so that you can produce a Proper Proof and then ultimately use the proper proof to confirm your metering and exposures as well as your development.
However, before you can effectively use a Proper Proof you must first determine your personal EI rating for each film, developer and paper combination. Now you can see why professional black and white photographers only use very few films, developers and paper combinations. Famous photographers over time have used a single film and developer to produce some of the most notable photographs in history. They were able to truly master their medium by focusing and narrowing the variables. I think there is a lesson in this that we should all pay attention to. After establishing your SCT and personal EI rating then I will walk you through how to determine your normal, expanded and contracted development times to control contrast.
Why Make a Proper Proof?
First, let me define what a Proper Proof is and then the rest will fall into place. A Proper Proof is a contact print that is made using your negative and paper combination based on your SCT (standard contact printing time). Before I dive into the advantages and reasons behind making Proper Proof’s let me tell you how to make one and then I will walk you through how to use it to make adjustments in your process (exposures, development times, etc). Briefly your Proper Proof is the best friend you can have as a black and white photographer. It reveals any flaws in your process and gives you perfect feedback of how to make adjustments and correct any issues.
How to Determine your SCT
Before figuring out your SCT you need to develop a blank piece of film using your standard process which includes your target developer, stop bath and fixer, washing, etc. If you want to review my standard process for black and white film development you can do that now before moving forward.
For large format photographers this is a simple process because you just take a blank piece of film from the box and develop it using your standard process. For roll film users (120 or 35mm) you need to load your film in your camera, keep your lens cap on and expose the entire roll before unloading into your tank and following your standard development process. A word of caution here. Make sure you are using a well-documented process that you can repeat every time. Pay close attention to your temperature control, your agitation technique, etc. I only use distilled water in my developer so that if I ever have to develop film in another location my water is the same.
After your blank piece of film dries you now have a piece of film that is effectively your film base + fog. In simple terms your film will allow a specific amount of light to pass through it and this is unique for each of us based on our local variables. If you had a densitometer you could measure your film base + fog, but we are going to do that visually.
How to Make the Proper Proof
Now proceed to your darkroom and setup your enlarger for making a contact print. I picked up an old Beseler 67C for $25 that I use as my contact and proper proof printing station. I rack the head all the way up so I never have to worry about changing the intensity of the light source. Next I put in my #2 variable contrast filter for large format sheet film and 120 roll film. If you are a 35mm user then you need to use a #3 filter. I personally use a 75mm lens and set it to f/11. These variables should never change once you get setup. You don’t have to use my exact setup, but whatever you decide make sure you document it and keep it the same. In theory you could use a low watt house bulb if you could control the height and light distribution.
To make my negative lay flat against my paper I had a local glass company make me a piece of 3/8″ plate glass and polish the edges. I had them cut it to 11″ by 14″ so I would have plenty of overlap for an 8×10 or 8 1/2 x 11 print. For my base I have a piece of smooth rubber mat that I picked up from Home Depot. You are simply going to lay down your paper with the emulsion side up, then your negative with your emulsion side down and then your glass on top of the stack to make the contact print. Your emulsion side on your negative is the dull side and on your paper it should feel slick. Don’t forget to assemble your contact print sandwich under an approved darkroom light for your paper type.
Next, make 3 second interval exposures across your contact print. You are shooting for a SCT time between 12 and 30 seconds. I use 4×5 or 8×10 sheet film so when I do 8×10 sheet film I just use an 8×10 piece of paper. When I test 4×5 film I cut an 8×10 piece of paper into half on each side and make 4 4×5 sheets of paper. For roll film users you can cut a strip of 8×10 paper long wise that is at least as wide as your film.
I use an old white mat board as my masking tool. Either using your enlarger timer or a metronome to work your way across the print in standard sized increments. For 4×5 sheet film I do about 1/4″ increments. You can figure out what you need to do in your own environment. Next, develop the print with your standard printing process. For RC papers develop at least 60 seconds and for fiber papers at least 90 seconds, but I recommend 2 minutes. Then 30 seconds in the stop bath and at least 30 seconds in the fixer before turning on the lights.
You are looking for that transition from grey to maximum black (DMAX) between 12 and 30 seconds. Anything short then 12 seconds is too short and longer than 25 or 30 seconds you probably need to adjust your lens aperture and test again to reduce the time. The transition from grey to DMAX is your standard contact printing time (SCT). If you are using RC paper then let it dry for a few minutes or even use a hair dryer to help things along. If you are using fiber paper you need to wait for the dry-down effect or if you are a little crazy you could microwave your print for 15 or 20 seconds and check it and maybe a few seconds more depending on your paper and microwave. Otherwise I let me fiber prints dry over night. The key point is to evaluate the contact print when it is dry and under bright lighting. You are looking for that last transition from grey to maximum black (DMAX) and then you have your SCT established.
Okay, you thought you were done. Well, almost. I am a stickler for details so I highly recommend that you verify your SCT. It is absolutely critical that you are using the proper SCT. Don’t rush this step or minimize the importance of it. The best way to do this is to make another contact print and cover half of your paper with your mat board. Expose it for 2 seconds less than your SCT. Then just flip your mat board over and expose the other half for your SCT. You should see a very slight difference between your underexposed half. If not, then your SCT is wrong and you need to make an adjustment. If you don’t see any difference then your SCT was too long and you need to shorten it. Once you have successfully verified your SCT then it is time to move to the next step of determining your personal EI rating for your film and developer combination.
How to Use Your Proper Proof
In the real world we are making a proper proof to evaluate your negatives and development process. When you have everything working together as a single unit the Proper Proof is one of your most powerful tools as a photographer. If you have a couple different exposures of a scene it can literally tell you which negative to print. Since your development process controls range of contrast and your exposure controls density you need to have them both correct. After you have established your SCT then when you make a Proper Proof with your negative it should look very good. If the print is too dark, too light, too much contrast, etc then you have a problem and your Proper Proof is your teacher. I have listed the most common problems for your consideration.
- If your photograph is too dark then your film was either underdeveloped and/or it was underexposed. In either case you need to get to the bottom of the problem and fix it for the future. I lean towards underexposure for this problem and this is why having your own personal EI rating is critical. Worse case scenario if you don’t have a personal EI then rate the film at half the box speed until you can properly test. You are effectively giving your film an extra stop of exposure by doing this. Don’t be surprised if your personal EI rating is a little less than half to get good shadow detail and overall exposure.
- If your photograph is too light then you have the opposite problem. Either your film was overdeveloped and/or overexposed
- Notice that I used “and/or” because you could have both problems.
- If you have too much contrast then you probably overdeveloped. Meaning your developed for too long and if you understand how film is developed your highlights will continue to develop with more time and your shadows level out earlier in the process.
- If your photo seems flat to you then you overdeveloped.
No one makes perfect negatives so don’t get discouraged if your Proper Proofs are not always “perfect”. I have printed many negatives that were not optimal, it is just a lot more work to make a print.
Many people are concerned that by adding the extra exposure they are going to blow out their highlights. That simply won’t happen if you are developing your film properly.
If you are doing everything right then you should end up with a negative that has strong shadow detail, printable highlights and the middle tones have good exposure too.
Ideally, you want a negative that has strong shadow detail, printable highlights, and good overall exposure in the middle tones.
What’s Next?
In the next article we will take our SCT time that we established in this article and expose some films to determine our personal EI rating. Then we will move on to validating our zones and then figuring out our development times. Stay tuned and be sure to comment at the bottom of the article if you enjoy this series. For other darkroom related articles refer to “Tim’s Darkroom Corner” section at the top right corner of the site.
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Tim Layton
© Tim Layton – All Rights Reserved – 2011. You may not republish or use any information or media of any format, in part or in whole, without my written permission. For permission and more information you can contact Tim Layton on the web at blog.timlaytonphotography.com or via email at tim@timlaytonphotography.com or via the telephone at 314.972.4900. Visit Tim’s latest photos online at Flickr.







Nice article. It’s useful basic information, but I don’t know how often it gets taught/mentioned these days.
By the way, you’ll want to correct the line “If your photo seems flat…” to say underdeveloped.
Thanks for visiting and commenting. I am not sure I understand what you mean when you say “It’s useful basic information, but I don’t know how often it gets taught/mentioned these days.” Write back and give me some more details. In lieu of your additional comments I can tell you that I use proper proofs every single time I make a fine print. In fact every professional black and white fine art photographer that I know as well as many advanced amateurs do as well. Proper proofs are a central feedback loop when using the zone system to control every aspect of your photography (exposure, development, printing). In addition to being the ultimate teacher it also can help you decide which negative will print the best. Without it one would be guessing and flying blind. It is also assumed that you have properly tested your film for your personal EI and established N, N+ and N- development times.
Tim, I’m wondering why you suggest using a #3 contrast filter for 35mm and #2 for medium and large format. Does it have something to do with the film base being darker?
Personally, I’ve determined my contact printing time to be the point at which the film base+fog density matches that of the paper which has no film covering it. Both should be at Dmax.
Dan, thanks for the comment and question. It is a question I often get when talking about 35mm film and darkroom techniques. The comment I made about using a #3 filter for proper proofs vs. a #2 for 120 and large format actually has nothing to do with the actual printing time. I rarely shoot 35mm film but when I do I use the logic I will state next. Also, my proper proof times for my 35mm negatives are in fact different from my 120 and large format sheet films because the fb+f is different. I intended the comment to be more of advice than anything else. However, let me give you my underlying thoughts on why I suggest a #3 filter for 35mm film as a starting place. Film base + fog (fb+f) only effects printing times as you stated. In fact it has no effect on contrast or overall print quality as it is simply printed through. If your 35mm negatives have to be printed with a higher contrast filter it indicates that your negative is soft or has a lower contrast. Softer being defined as a negative that was developed for less time. The longer that film is developed the more pronounced grain becomes and some sharpness is thought to be lost. Since we are talking about 35mm and its small size as compared to 120 and large format, it is a good idea to shoot for soft 35mm negatives for the above stated reasons and then just bring up the contrast with a higher contrast filter in the enlargement process. This is also why I tell people that have not properly tested their b/w films to rate the film at half the box speed and develop for 10% to 15% less than the manufacturer’s specification sheet says because this should produce a softer negative if metered properly.