question about altering density results

[bgaspard]

Okay, I have read "The Negative" by Adams, but that was a while back. I think I am having a brain fart.

I just shot some Pan F and developed in 510 pyro, 7.5 minutes, 70 deg F, standard agitation (1st 30 sec, then 10 sec every minute). I checked my densities for III, V, and VIII. Here are the results (accounting for BD+F)

III = .52
V = .76
VIII = 1.24

V and VIII are coming out about where I want them, but III is coming in a little dense. .52 is around where I would expect zone IV to be. I want zone III to be closer to .35-.4

My plan is to decrease development by 30 seconds, thinking that will lower contrast a bit, but still keep my densities for the higher zones were I need them. Does this make sense? I just need to bring that Zone III density down a bit. Should I change ISO instead? Or maybe increase ISO to 64 and drop development to 7:15?

Any suggestions on a better way to obtain this goal. Which approach would give me the best results, without having to go out and shoot this test again?

Thanks for the help.

 

[MikeSeb]

Lower zone densities are more a factor of exposure; higher zones, of development. (I assume we are talking about negative densities here.)

You should consider decreasing exposure (ie, increasing EI) a bit, maybe a third or a half stop. I'd start by leaving development where it is and then alter to taste.

The other approach would be to look at your printed results, and if they're to your liking, declare victory and run with it. You can always make minor adjustments to exposure and development as you go forward.

 

[bgaspard]

I guess I'll try shooting the next roll at ISO 64. I haven't got a chance to print with these negatives yet. I think they will print fine, but want to be absolutely sure before I start.

I read that some other people are using this film/dev combo with times of 6:30, same agitation, same temp (70 F), and ISO 50. That is one minute less development than what I was using. I think those people may have been using rotary development though. I used manual steel or plastic tanks. I may try this regimen, but as you said, development affects the density of higher zones. The densities of V and VIII were spot on in my tests. I don't know, guess I'll just have to experiment more.

 

[gainer]

The values you gave plot on a straight line on semi-log paper. You need to know the base + fog density and the density of unexposed, fixed film to complete the picture and decide whether to change exposure or development or neither. As it stands, the least possible base density is 0.3, which seems a bit high considering that there will be some curvature as zero log exposure is approached. In my opinion, you could shift the exposure at least one zone, making zone 3 an f-stop less than your current value without losing any shadow detail.
My plot is the equivalent of plotting log density against Zone on ordinary graph paper for showing the shape of the curve.

 

[gainer]

After I shot off my digidal mouth, I reread the original post and found that the densities reported have been adjusted for base + fog. I think all the densities are higher than they need to be. I also think that the slope of the curve is about Normal and that any reduction of development that would bring the Zone III density down to 0.35 or so would make a normal scene brightness range unprintable on grade 2 paper.

510 Pyro is a staining developer. You didn't mention how you measured your densities.

Is it possible that either the reading of the scene brightness was in error or that the camera lens-shutter system is off? I know from personal experience that blunders in setting f-stop and shutter speed are possible. In this case it looks like about a 3 f-stop error which could come about if the shutter were set for 1/10 second intead of 1/100, or the lens was focused wide open and not stopped down.

Anyway, I don't think a change of development is the answer, unless you find one that reduces film speed a great deal.

 

[Donald Miller]

You failed to mention whether you checked for film speed. That should be your first step. Film speed would be the first exposure at four stops below meter indication that yields a .10 density above FB+fog. You should check the film at 1/2 stop departures either side of the box speed

If I were making a guess, I think that you will find that you need to increase the EI of the film by what Mike indicated and that you will need to bump your development by about 20%...but that is a WAG.

This would drop your lower densities as well as your upper densities and the compensating increase in development should bring your upper densities back into line with where they will print for you.

 

[bgaspard]

. I think all the densities are higher than they need to be. I also think that the slope of the curve is about Normal and that any reduction of development that would bring the Zone III density down to 0.35 or so would make a normal scene brightness range unprintable on grade 2 paper.

I know the densities are a little high, but according to most of the literature I have read, Zone V and VIII are in optimal range for diffusion heads. I am using a Vivitar VI "Dioptic Light Pipe", which is kind of halfway between condenser and diffusion.

510 Pyro is a staining developer. You didn't mention how you measured your densities.

I do not have access to a true densitometer, I am using Vuescan. Not sure if the stain makes a difference, but it probably does.

Is it possible that either the reading of the scene brightness was in error or that the camera lens-shutter system is off?

Nope, triple checked exposures, camera just had an overhaul, and I get very accurate results with proven film/dev combos.

You failed to mention whether you checked for film speed.

Nope again, I just started with suggestions found online. I have never tested for film speed, so I guess I should figure out how. I shot it at box speed because everything I have read states that 510 pyro gives box speed.

Also, my conditions for the test were as follows:

Outside, medium bright day, shot at a grey card a few feet away, which filled the frame. I made zone III and VIII exposures by adjusting shutter speed.

Thanks for all of the info, any other suggestions would be very welcome.

 

[smieglitz]

I'd guess as gainer did that you have an exposure error at zone III caused by a mechanical discrepancy in shutter/aperture (or else pilot error which you state probably didn't occur since you triple-checked exposures). You could test this a couple different ways. Shoot several exposures at zone III (or V or both) at different shutter/aperture equivalents to see if the density is fluctuating when it should remain relatively constant. Another (better) way is to shoot the zone V exposure and then slap .60 neutral density filtration over the lens and use the same exposure setting to get zone III. That eliminates any error caused by a bad shutter speed or aperture change.

However, the first thing I'd suggest is testing the paper you will be printing on using a Stouffer 21-step density scale. This will let you measure the actual exposure scale of the paper and give you the target densities for the zones rather than having to rely on Ansel's suggestions. Based on the materials I generally use, your zone III density looks very high, the zone V slightly high, and the zone VIII slightly low. That suggests overexposure and underdevelopment to me, just the opposite of what most people beginning the zone system might tend to find. And, your plans to decrease development seem to be the opposite of what needs to be done if I'm reading all this correctly. (I've never used that particular film but Pan F is box speed ISO 50, isn't it? Moving to ISO 64 seems to be the right direction then for you, though unusual IME. FWIW, I like zone V around .70 and zone VIII around 1.30 above fbf. Hopefully, the lower zones come in with zone I around .10 - .15 and zone III maybe .35, though YMMV.)

And a question: are you metering for zone V, making an exposure, then metering again for the other zones and making the relevant exposures, or are you taking one meter reading and then simply shifting shutter speeds from that point to get the different zone exposures? If the former, the density discrepancy could be caused partially by a non-linear meter.

You probably should backtrack a bit, find the zone I speed point and then nail down the proper zone V density. Zone I anchors everything with respect to exposure and with that value in place, finding the correct development for zone V placement lets you always have a standard reference point to check. The other zones can then be visualized relative to those two zones and the paper scale, and the process adjusted accordingly.

Hope this helps and makes some sense.

Joe

 

[bgaspard]

However, the first thing I'd suggest is testing the paper you will be printing on using a Stouffer 21-step density scale. This will let you measure the actual exposure scale of the paper and give you the target densities for the zones rather than having to rely on Ansel's suggestions. Based on the materials I generally use, your zone III density looks very high, the zone V slightly high, and the zone VIII slightly low.

I haven't settled on a paper yet, and I do not have a step wedge. I am still pretty green. I am finally setting up my darkroom today, and have these papers at my disposal: Ilford semi-matte multigrade, Varycon, Kentmere multigrade, Arista Edu II, and Ilford glossy multigrade. I was hoping to find some an acceptable density range, the affter sellecting my favorite paper, fine tuning my negative densities.

You probably should backtrack a bit, find the zone I speed point and then nail down the proper zone V density. Zone I anchors everything with respect to exposure and with that value in place, finding the correct development for zone V placement lets you always have a standard reference point to check. The other zones can then be visualized relative to those two zones and the paper scale, and the process adjusted accordingly.

Hope this helps and makes some sense.

I think this is what I will do. Let me walk this step by step to make sure I don't miss anything.

1. At 50 ISO, meter and shoot grey card in average lighting conditions at four stops below metered suggestion.
2. Repeat step one for 25, 32, 50, 64, and 80 ISO.
3. Develop as usual, I think I will try 7:00 this time.
4. Find which ISO setting produces the .10 above FB+D first. Use this as my standard ISO setting.
5. Shoot zones I, III, V, VIII, and X at new ISO setting, using the same equipment as step 1, same lighting, etc.
6. Develop as usual, then record densities.
7. See how they match up with suggested densities.
8. Adjust any development issues.
9. Find a step wedge. Adjust for my chosen paper.

 

[smieglitz]

...
I think this is what I will do. Let me walk this step by step to make sure I don't miss anything.

1. At 50 ISO, meter and shoot grey card in average lighting conditions at four stops below metered suggestion.
2. Repeat step one for 25, 32, 50, 64, and 80 ISO.
3. Develop as usual, I think I will try 7:00 this time.
4. Find which ISO setting produces the .10 above FB+D first. Use this as my standard ISO setting.
5. Shoot zones I, III, V, VIII, and X at new ISO setting, using the same equipment as step 1, same lighting, etc.
6. Develop as usual, then record densities.
7. See how they match up with suggested densities.
f8. Adjust any development issues.
9. Find a step wedge. Adjust for my chosen paper.

Really, put step #9 first and test the paper you think you will standardize upon. The semi-matte is going to give you different results from the others since the d-max won't be as great. I'm unfamiliar with a couple of the other papers you list so can't comment on them. But, I'd suggest picking only one to start and making sure it is something readily available and of fresh stock (e.g., Ilford Multigrade glossy).

I'm also curious as to why you are using a pyro developer unless you are doing sheet film and planning on contact printing. Pyro to my mind is kind of an esoteric developer and one that is relatively toxic. Why not use something like D-76, ID-11, or HC110 when starting out? Simplicity always seems to work the best when starting something new.

And again, reducing development time will only reduce contrast and I don't think that is what you need to do, at least not yet. You can't get a handle on proper development until you have the exposures correct. Changing both exposure and development simultaneously at the start will only complicate things unnecessarily. Figure out the paper scale and EI of the film first, then adjust the film development later.

You can pick up a Stouffer wedge for about $10 from a graphic arts store or a photo supplier like Bostick and Sullivan. If you are shooting sheet film you can also use such a step wedge and expose a sheet to zone X with the step wedge over the film to get the entire set of zone densities exposed simultaneously. (See Schaeffer's Ansel Adams Guide to Photography book for an explanation of this technique.) And, you can use the step wedge to test alternative printing emulsions like cyanotype, etc., should you go down that path. It really is the best $10 you'll ever spend for darkroom work.

Or are you doing 35mm roll film? If so, I would suggest making a zone V exposure first and then following with exposures for zone I at the various ISO settings. Sometimes you cannot tell where the test started because the zone I exposure at a certain ISO may disappear into the fbf. Having a zone V-ish marker frame helps to interpret the results.

Henry Horenstein's B/W book gave another nifty technique for determining film speed and without a densitometer too. (Testing as follows would eliminate the Vuescan and any possible problems from it.) He suggested shooting blank frames (with lens cap on) between every two zone I test frames and then simply laying a piece of a wratten gelatin 0.10 neutral density filter over the blank frame to compare the density of the adjacent frame visually. So, the frame sequence might go something like:

01) Zone V @ ISO 50
02) blank
03) Zone I @ ISO 12
04) Zone I @ ISO 16
05) blank
06) Zone I @ ISO 25
07) Zone I @ ISO 32
08) blank
09) Zone I @ ISO 50
10) Zone I @ ISO 64
11) blank
12) Zone I @ ISO 80
13) Zone I @ ISO 100
14) blank
15) Zone I @ ISO 25
16) Zone II @ ISO 25
17) Zone III @ ISO 25
18) Zone IV @ ISO 25
19) Zone V @ ISO 25
20) Zone VI @ ISO 25
21) Zone VII @ ISO 25
22) Zone VIII @ ISO 25
23) Zone IX @ ISO 25
24) Zone X @ ISO 25

Two stops under and one stop over the box speed should cover you in a sequence that I'm assuming will turn up EI 25 for your true film speed. Plus, you will be able to see how the entire scale prints in a glance. (You will essentially be making your own density step wedge.)

Joe

 

[Donald Miller]

I haven't settled on a paper yet, and I do not have a step wedge. I am still pretty green. I am finally setting up my darkroom today, and have these papers at my disposal: Ilford semi-matte multigrade, Varycon, Kentmere multigrade, Arista Edu II, and Ilford glossy multigrade. I was hoping to find some an acceptable density range, the affter sellecting my favorite paper, fine tuning my negative densities.



I think this is what I will do. Let me walk this step by step to make sure I don't miss anything.

1. At 50 ISO, meter and shoot grey card in average lighting conditions at four stops below metered suggestion.
2. Repeat step one for 25, 32, 50, 64, and 80 ISO.
3. Develop as usual, I think I will try 7:00 this time.
4. Find which ISO setting produces the .10 above FB+D first. Use this as my standard ISO setting.
5. Shoot zones I, III, V, VIII, and X at new ISO setting, using the same equipment as step 1, same lighting, etc.
6. Develop as usual, then record densities.
7. See how they match up with suggested densities.
8. Adjust any development issues.
9. Find a step wedge. Adjust for my chosen paper.

There are several ways to accomplish what you need to determine. You will get different suggestions from different people. After many years of doing this, I will suggest what I have found works for me.

The place that I begin today is with the exposure scale of the paper. There have been several differences reported recently insofar as the contrast or the exposure scale of different papers with supposedly the same contrast grade. For instance I have heard from Sandy King that Ilford paper has an ES of 1.60 (very near what the old grade two Azo exhibited)...certainly not the 1.00 to 1.10 that the Zone System would indicate that we expect. Beyond that there have been several other threads recently that indicate that one paper or the other is either lower or higher in contrast than one would expect.

The way to determine for yourself what the paper scale is with your equipment, developer, and process is to begin by exposing the paper to a calibrated standard. A Stouffer step wedge will fill that requirement.

Once you know what the paper will handle than you can begin to determine what a negative needs to possess to print well on that paper.

The alternative is to expose and develop your film to some arbitary standard and then deal with the paper scale in the printing process. Not always easy especially with certain graded materials and certain developers. The alternative way to do this is to do what you are engaged in...that is to develop negatives to an arbitary standard that was established many years ago. In that way you can begin by finding the speed point of the film. Next you can find at what point the zone VIII density matches this arbitary standard. If you know where Zone I with is placed and where Zone VIII falls than every other Zone will fall where it will. (being a condition of the film's characteristic curve, the developer activity and your processing procedures).

My time spent in writing what I have stated is to get you out the door making meaningful photographs as expeditiously as possible. Good luck.

 

[bgaspard]

The way to determine for yourself what the paper scale is with your equipment, developer, and process is to begin by exposing the paper to a calibrated standard. A Stouffer step wedge will fill that requirement.

I will pick up a step wedge as soon as possible. Hopefully I can find one that fits in a 35mm or 120 carrier. Next, try to adjust my development to match the papers capabilities (when I decide which one I want to use).

I few more frames, processed them for 7 minutes (30 sec less than before) and here is what I came up with:
I .12
III .38
V .8
VIII 1.46

The upper densities are too high, but the lower ones are coming in a little closer. Time to make more adjustments.

 

[Donald Miller]

I will pick up a step wedge as soon as possible. Hopefully I can find one that fits in a 35mm or 120 carrier. Next, try to adjust my development to match the papers capabilities (when I decide which one I want to use).

I few more frames, processed them for 7 minutes (30 sec less than before) and here is what I came up with:
I .12
III .38
V .8
VIII 1.46

The upper densities are too high, but the lower ones are coming in a little closer. Time to make more adjustments.

Your step wedge can be contact printed on the paper. You will not find one that will fit the carriers you mentioned. They are usually less than $12 from Stouffer.

 

[smieglitz]

...
III .38
V .8
VIII 1.46

The upper densities are too high, but the lower ones are coming in a little closer. Time to make more adjustments.

Yes. The low densities look better and the upper ones are too high. The higher density values for the upper zones should not be happening given the decreased develpment. There is some inconsistency affecting the results.

 

[gainer]

There is a step wedge that fits a 35 mm frame. I trimmed and taped one into the film frame of an old 35 mm camera that I use as a printing frame for film tests. You can project one from the enlarger to paper or film as well, but beware of stray light and uneven illumination of the enlarger field.

 

[bgaspard]

Yes. The low densities look better and the upper ones are too high. The higher density values for the upper zones should not be happening given the decreased develpment. There is some inconsistency affecting the results.

I thought the same thing. This test was done much more haphazardly, so I will repeat it anyway.

Your step wedge can be contact printed on the paper. You will not find one that will fit the carriers you mentioned. They are usually less than $12 from Stouffer.

Stouffer has transmission step wedges for enlargement in size 35mm throught 4x5. I think, but could be very wrong, that these fit in your negative carrier. I was hoping to use one of these because I feared contact printing the step wedge would be yet another deviation from my normal routine. If I can project the step wedge negative onto the paper, I thought it would imitate my process more efficiently.

http://www.stouffer.net/Photo.htm#Transmission%20Projection

Thanks again everyone for all of your help, I really appreciate the suggestions.