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Question about develoment time check

Tofek

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Hello,
I'm trying to find a way to check my developing time, APX100 in Rodinal 1+25. I'm currently at 8 min / 20°C. The thing is, I regulary print on grade 5 to get optimal contrast and I've been wondering if the problem is the development or other (enlarger, etc.). So I read about the method of Bruce Barnbaum in his book. He recommends to expose a zone V on paper (comparing it to a 18% card) and then to expose a zone IX catured on the negative with the same time and see if it is blank or very light grey. Anyway, I want to find a way of exposing zone V without a grey card, and I'd like to ask you if the method I found is correct : it is to find the reference time of the negative and then expose the zone IX capture with that reference time, without using zone V as a reference. Will the reference time give me the correct equivalent of zone IX ? Supposing that the exposure is correct.
I hope you get what I mean.

Thank you in advance,

Krystof.
 

paul_c5x4

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Have a read of Barry Thornton's articles on personal development times and film speeds. He gives advice on how to calibrate your workflow without having to use grey cards or step wedges.
 

pdeeh

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That's excellent advice, those articles really helped me - very practical and straightforward.

You can find them here:

http://www.barrythornton.com/ under the "Technique Guide" section
 

Thomas Bertilsson

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There is nothing wrong with printing at Grade 5.

But if you are like me, and like your negatives to print well at Grade 2 or 3, then you have to make your negatives higher in contrast, meaning you need to develop them longer. I suggest starting with adding about 12% and go to 9 minutes, print a couple of frames and see what happens.

I like to be able to have wiggle room when I print. Most of my negatives print well at around Grade 2 to 3, but sometimes I want a bit of extra punch to the print, and I use the Grade 4 or 5 filters to either burn in certain areas, or give the whole print the high contrast treatment.
If my negatives were such that my 'normal' print would be at Grade 5, and I needed more contrast, it would be very difficult to do.

Just something to think about. Increasing or decreasing negative contrast is a basic control point of your process, so look at your negatives critically, and adjust developing time as necessary so that you can print at your preferred contrast grades. It's entirely in your hands.

 

Chris Lange

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The problem for me isn't so much my negatives, but that commercially available negative films are designed from the get go to display a full range of smooth tonality...I like things rough and coarse. Rodinal 1:25 and Delta 3200 with a red 25 starts to get me where I like to be.

Edit: I should clarify this is for certain pictures only...often I am perfectly content printing grade 3 with fp4+ or APX100 shot at 80 or 100.
 
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Tofek

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Thank you for yur answers.

Paul and pdeeh thanks for the link, I read it and it actually confirms what I wanted to do.

Thomas, I see what you mean. I know that I will have to increase the dev time whatever happens because I don't like printing at the limit grade 5, and having no room for increasing contrast if I want to. But I wanted to do this test, to check if my developing is too short or if the cause of the low contrast is eslewhere. Anyway I'm having fun with these tests for now, and will have even more fun printing from the negatives developed to my taste.
 

Thomas Bertilsson

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Understood. If your Rodinal is contaminated, or beginning to exhaust (unlikely, but I've seen reports of R09 with sudden loss of activity lately), then your negatives could be under-developed, even though your developing time is correct. That is definitely true.

If your low contrast negatives is a sudden change from what they used to be, then it is wise to suspect the developer, and my advice would be to purchase some fresh developer.
If your negatives have always been low contrast, the same as you get now, at 8 minutes developing time, then it's more likely to do with your technique and you simply need to develop the film for a longer amount of time.

Good luck!
 
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Tofek

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Yes, my prints have always been muddy and I'm beginning to realize it. So it's likely my fault. And my agitation is very soft too, I agitate two times, gently, every minute. So it may also come from here. Anyway I prefer increasing the dev time rather than changing agitation, it became such a habit that would be harder to change.
Btw, I also tested the exposure, and I'm seeing a fog on the supposd zone 0, at 100ASA. By how much would you increase the ASA rating ? I must admit that I don't want to bother with thirds of stops and skip directly at 200ASA...
 

MattKing

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I would suggest increasing your agitation somewhat - how about four gentle cycles each minute or two gentle cycles each 30 seconds?

That will help remove local developer exhaustion from the list of potential causes for your low contrast negatives.

An inaccurate thermometer is another likely cause. As long as your thermometer is consistent, you can (within limits) compensate for potential inaccuracy by increasing development time. If the thermometer is inconsistent it needs to be replaced.

I'm not exactly sure I understand what you are saying with respect to Zone 0 exposure, but if you are wanting to increase the exposure, you need to decrease the Exposure Index ("EI") set on your meter.
 
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Tofek

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The thermometer should be acurate, it isn't old and is quite precise (0,2°C).
As for agitation, as I said I prefer to change time not only for the habit of agitation, but also because the grain will be bigger with more agitation (you'll tell me not to use Rodinal if I want small grain... ).
Concerning the zone 0. I made the exposure test : meter a wall (zone V) and close the diaphragm 5 stops to get to zone 0. If correctly exposed, there shouldn't be fog, if I understood well. But there is some, in my case. Which means that I over expose the negative when setting my meter at 100ASA. That's why I was talking about increasing the EI.
 

MattKing

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With thermometers, precision and accuracy are two separate issues.

It could be precise, but not calibrated properly.

And with respect to agitation and Rodinal, I think you will find that if you keep the cycles gentle you will continue to minimize grain.

Unless you have a light leak, the fog comes from the film and development, not exposure. Increasing the exposure will raise your shadow detail above the fog, whereas reducing exposure will cause more detail to be obscured by fog.
 
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Tofek

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But I don't get it then...I thought that zone 0 should have zero fog, zero silver reduced., as it is said in Barnbaum's book ?
 

Thomas Bertilsson

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Agree.

You can do a simple test by simply turning off the lights and check for light leaks. If there are any, plug them, until your darkroom is safe.
Then make a print without the safelight on. If the prints still look the same, then you don't have a light leak problem.
 

MartinP

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All the advice pre-supposes that your negs have shadow detail where you want and expect it of course. If not, then increase exposure too.
 

cliveh

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I would suggest that having to print on grade 5, or any high magenta value for multigrade is not a good idea. Why not try and adjust your camera exposure and negative development time/temperature until you can consistently print on grade 2 or with zero filtration on multigrade?
 

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You already did the test ["I usually print on Grade 5"] so just increase film development by 25% to give you some more leeway so most images print on grade 2 or 3.

Explanation: Development time tests are to save time and money. Otherwise you need to do experimentation by shooting typical scenes and, processing negatives without knowing if they will be printable on the commonly available paper grades. Since you have already done that experiment and determined your negatives print on grade 5, there is no need to go backwards from there.
 
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Tofek

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I wanted to do the tests anyway, to understand a little more what's happening, why the contrast is low, how much should I increase the time etc. But I see your point.

For the fog however, I don't see why there should be more fog on a field exposed as zone 0 than on a field which received no exposure ( lens cap on ) ? That's the case in my test, and it proves that the light meter didn't give me zone 0 exposure (respectively zone V) but a little more (overexposure). Isn't that correct ? I'm trying to understand...

Thanks for the replies guys
 

ic-racer

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I wanted to do the tests anyway, to understand a little more what's happening
Click to expand...

There are a lot of ways to do the tests. This way is based on sound principles and is pretty easy to do and to understand: Do a Zone I one exposure test at various ISO/ASA settings and keep good notes, and process the film. Place the processed and dry negatives of zone I over your meter. The one that drops exposure by 1/3 stop over unexposed film base equals 0.1 log d and that is the one to base the speed on. Next, using the speed you had just determined, you can shoot a zone VIII target. Do that on three rolls. Process the first roll for your usual time. Place the zone VIII negative in the enlarger so you can also see the film edge. Do a test print so the film edge is just black. Now the Zone VIII should be just off-white, very slightly gray. If it is totally white, then process the next roll for 25% time less and repeat the test. If the Zone VIII is a darker gray, then increase development 25%.
 

MattKing

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If there is no image bearing detail in your "fog" it sounds to me that you are experiencing one of two things:

1) you have problems with flare in the system; or
2) your "fogged" area was essentially subject to a below threshold amount of light before the exposure, and the additional Zone 0 light bumped it up over the threshold.

Is there any chance we are thinking of "fog" in two different ways?
 
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Tofek

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Ic-racer, that's basically the test that I did, except for the measuring of density with light meter (I did it by looking at zone 0 which should have no density) and for the zone VII (I used zone IX to determine the dev time).

Matt, yes that's possible. In fact I meant density, not fog. These are two different things, right ? Your 2) point is what I think is happening, that zone 0 received light when it shouldn't have.

Silveror, shutter speed were checked a year ago so they should be ok.
 

ic-racer

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Tofek said:
(I did it by looking at zone 0 which should have no density) .
Click to expand...

Be careful! Zone 0 is the film density resulting from one stop of exposure less than zone I exposure. Its density is not defined. You don't want to base anything on its density value. It is NOT defined as zero exposure or zero density on film.
 
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