Massive Dev Chart question re: film speeds and development times

[Simon R Galley]

Has to be....!!!

Simon ILFORD Photo / HARMAN technology Limited

 

[lhoff601]

Wow! I sure didn't expect so many responses. Thank you, all!

I am *very much* an experimenter, as I feel that's the best way to learn. (My programmer colleagues disagree with me. But, that's another story...)

In particular, I'm interested in how m-carter does what's described below:

With one 36 exposure roll of 35mm film, I can test 4 iso's at 4 different developer time & agitation combos, and have 2 more brackets of 4 iso's to fine tune or test harder pushes. One roll and 2 or 3 batches of 1-shot developer. That's a couple hours and less than ten bucks. You do need a good pair of scissors and a reel & tank. But you will know what dev. times work best for various speed ratings, and you will know which ISO is really the best for shadow detail and highlight tonality.

I'm having trouble understanding how to do this (especially the 4 different iso's on one roll -- how do you know where to cut the exposed roll into strips?). But, I want to. It sounds like a great thing for me to try.

Thanks, again!

 

[Simonh82]

You can see his description of his film test procedure in this post (there was a url link here which no longer exists)

It seems like a sensible, if fiddly procedure.

 

[M Carter]

You can see his description of his film test procedure in this post (there was a url link here which no longer exists)

It seems like a sensible, if fiddly procedure.

It's minor-fiddly - more of a pain if you use a changing bag. The benefit of it is if you just can't stand to waste stuff (like film). 4-6 tests per roll is pretty nice in that case.

But opening the camera back, applying a tab of tape, and then closing it back up - the longest part of that process is getting your arms into the bag (I do have a good dark film changing closet though). The tape tabs are very easy to find when you're cutting the film.

I'd say the #1 tip I'd add to this is: get some short, stubby scissors. They are way easier to work with in the dark, esp. in a bag!

 

[zehner21]

It's minor-fiddly - more of a pain if you use a changing bag. The benefit of it is if you just can't stand to waste stuff (like film). 4-6 tests per roll is pretty nice in that case.

But opening the camera back, applying a tab of tape, and then closing it back up - the longest part of that process is getting your arms into the bag (I do have a good dark film changing closet though). The tape tabs are very easy to find when you're cutting the film.

I'd say the #1 tip I'd add to this is: get some short, stubby scissors. They are way easier to work with in the dark, esp. in a bag!

How do you determine the time for a correct development?


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[pentaxuser]

Interesting use of the tape and tabs. I take it that turned-over tabs is so you can get your fingernail under the tab for easier removal? My worry would be that the thickness of the tape and in effect double thickness of the tab might prevent the film being wound back into the cassette or do you open the back at the end then re-wind the film manually and cut each piece as you feel the tab?

Obviously it works with manual rewind cameras but those auto-rewind cameras might have a problem as there is no way of preventing a full re-wind into the cassette.

Well no way as far as I know

Thanks

pentaxuser

 

[David Allen]

How do you determine the time for a correct development?


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You determine personal EI and development time by doing tests. I prefer 'real world' tests rather than using a densitometer. As I posted earlier you can use the manufacturer's times or the MDC BUT you have to be aware that this is purely a starting point. The reason for doing your own tests are that they relate directly to your own equipment, metering method, agitation regime, etc, etc.

When someone comes on one of my courses and wants to pin down EI and development time, I always take them through a 'real world' testing regime. This involves doing all of the testing based upon what your eyes tell you rather than what a densitometer tells you. So what the hell is 'real world' testing regime?

Well, in my opinion, the key to achieving consistently good negatives is the correct placement of your shadows when exposing the film and ascertaining the correct development time for achieving good separation without losing the highlights. A simple and relatively quick way to way to pin all this down for the future is to do the following (WARNING: reading these instructions is more time consuming and a lot more laborious than actually doing it!!):

1. Find a scene with with a good range of tones
2. Using the box speed, meter the darkest area in which you wish to retain shadow detail
3. Move the camera so that you are only photographing this shadow area
4. From the meter's reading close down the aperture by 2 stops or increase the shutter speed by two stops and then expose 6 frames at: the given exposure then +1 stop, +2 stops, -1 stop, -2 stops and -3 stops less than the meter has indicated

5. Process the film

6. Using the frame that was exposed at -3 stops less than the meter indicated (which should be practically clear but will have received lens flair and fogging - i.e a real world maximum black rather than an exposed piece of film that has processing fog) and do a test strip to find out what is the minimum exposure to achieve maximum black - Print must be fully dry before assessing this
7. Do another test strip with the first exposure being what you have selected for achieving maximum black minus your dry-down compensation then plus 1 second, 2 seconds, etc
8. The time that achieves full black inclusive of compensation for dry-down is you minimum exposure to achieve maximum black for all future printing sessions - print must be fully dry before assessing
9 You now know the minimum time to achieve full black inclusive of exposure reduction to accommodate dry-down
10. Using this minimum exposure to achieve maximum black exposure time, expose all of the other test frames.
11. The test print that has good shadow detail indicates which exposure will render good shadow detail and achieve maximum black and provides you with your personal EI for the tested film/developer combination

12 If the negative exposed at the meter reading gives good shadows, your EI is (when metering shadows where you wish to retain good detail) the box speed (i.e. for 400 film you need to set your meter at 400)
13. If the negative exposed at +1 stop more than the meter reading gives good shadows, your EI is (when metering shadows where you wish to retain good detail) 1/2 the box speed (i.e. for 400 film you need to set your meter at 200)
14. If the negative exposed at +2 stops more than the meter reading gives good shadows, you EI is (when metering shadows where you wish to retain good detail) 1/4 box speed (i.e. for 400 film you need to set your meter at 100)
15. If the negative exposed at -1 stop less than the meter reading gives good shadows, you EI is (when metering shadows where you wish to retain good detail) double the box speed (i.e. for 400 film you need to set your meter at 800)
16. If the negative exposed at -2 stop less than the meter reading gives good shadows, you EI is (when metering shadows where you wish to retain good detail) 4x the box speed (i.e. for 400 film you need to set your meter at 1600)

You have now fixed your personal EI but there is one more testing stage to go.

1. Find a scene with with a good range of tones
2. Using your EI, meter the brightest area in which you wish to retain highlight detail
3. Move the camera so that you are only photographing this highlight area
4. From the meter's reading open up the aperture by 3 stops or decrease the shutter speed by three stops
5. Expose the whole roll at this setting
6. In the darkroom, process one third of the film for manufacture's / MDC / a friends recommended development time

7. When dry put negative in the enlarger and make a three section test strip exposing for half the minimum black time established earlier, for the established minimum black time and for double the minimum black time.
8. Process print and dry it.
9. If the section of the test strip exposed for 1/2 the minimum black time gives bright highlights with a trace of detail then the film requires 20% more development
10. If the section of the test strip exposed for the minimum black time gives bright highlights with a trace of detail then the film is correctly developed
11. If the section of the test strip exposed for double the minimum black time gives bright highlights with a trace of detail then the film requires 20% less development
12. You can use the rest of the exposed (but unprocessed) highlight test film to fine tune the development time (i.e. if you have identified the need for +20% development, process the second bit of film for the time you previously used plus 20%. Redo the highlight test and either you will have the correct time or will see that it needs + or - 5% to be perfectly spot on. You can then the next bit of exposed but undeveloped film to do a final test.).

YES - it is VERY boring (but no more boring than taking densitometer readings and plotting curves) but . . .for the investment of minimal materials and a few of hours you will have pinned down so many variables that it is really worth doing.

Back in the real world, all you need to do in future is meter the shadows that you wish to retain good detail with meter set at your EI and then stop down the aperture 2 stops or increase the shutter speed by 2 stops. In the darkroom start your first test print with the minimum exposure to achieve maximum black (inclusive of dry-down compensation) and go from there.

Bests,

David.
www.dsallen.de

 

[M Carter]

Interesting use of the tape and tabs. I take it that turned-over tabs is so you can get your fingernail under the tab for easier removal? My worry would be that the thickness of the tape and in effect double thickness of the tab might prevent the film being wound back into the cassette or do you open the back at the end then re-wind the film manually and cut each piece as you feel the tab?

Obviously it works with manual rewind cameras but those auto-rewind cameras might have a problem as there is no way of preventing a full re-wind into the cassette.

Well no way as far as I know

Thanks

pentaxuser

Yep, that's it. I don't rewind (I'm sure it would be a mess)... just find each tab by feel and cut at that point.

With a modern (plastic generally) camera (not knocking that, still use my N90s and 8008s bodeis sometime) you'd want to finish the roll, and then just open the camera back and snip the film from the cassette -I'd assume anyway.

But as I recall, my Nikons don't just start rewinding on the last frame, I have to use the rewind buttons? Haven't used those for testing so can't recall, but in that case, you'd want to stop shooting before the last frame.

 

[M Carter]

You determine personal EI and development time by doing tests. I prefer 'real world' tests rather than using a densitometer. As I posted earlier you can use the manufacturer's times or the MDC BUT you have to be aware that this is purely a starting point. The reason for doing your own tests are that they relate directly to your own equipment, metering method, agitation regime, etc, etc...

David's methodology is extremely sound and you'll get a star on your forehead upon completion!

if it seems a bit too intense for your first testing go-round... I'd say try this as a starter:

• Google, research, etc and find the range of ISO, devs and dev times folks are using for your film. The internet is chock full of info that will give you a range of what works for people. It may be quite a wide range...
• Settle on a 4-stop range of ISOs (say, for HP5+ that might be 200, 320, 400, and up - your research will probably suggest a range as well, as people will "insist" a film has a true speed and everyone will insist it's a different "true speed"). Figure out the time range people are using for a regular developer - might be something like "many people use HC-110 dilution B anywhere for 6 to 12 minutes at 20c".
• Go through the one-roll tape-tab from earlier in the thread, or any similar way to be able to develop several ISOs at several different dev times.
• Keep in mind that contact sheets and prints at grade 2 or 2.5 or so will tell you far more than just louping the negs!!! Film holds more info than paper can.

You should be able to find which ISOs deliver the most shadow detail, and which processing times are optimal for a given ISO.

Once you've gone through that process, re-read David's list of steps and see what further info you might glean from that process if you want to go deeper.

And keep in mind you may have different results with the same film in different formats (35mm vs. MF, say). Testing MF is a little harder... you can get 2 bracket sets on a roll, with 2 blank frames in between, and a cut scrap of film to measure the halfway point... 35 is a great way to get comfy with testing.

Or... grab a copy of "way beyond monochrome" and read the film chapter. While they do cover density and gamma and using densitometers and making your own charts and graphs... they also have some very simple steps to get a handle on your film speed and development, and some very good "general" rules for exposure/development based on light conditions.

I came up shooting E6 for a living... it took me quite a while to realize it's really hard to give B&W film too much light, quite a reversal from reversal film!

 

[David Brown]

How do you determine the time for a correct development?

Some do extensive tests.

Most of us just start by following the manufacturer's directions and making adjustments as (and IF) necessary.

 

[pentaxuser]

Yep, that's it. I don't rewind (I'm sure it would be a mess)... just find each tab by feel and cut at that point.

With a modern (plastic generally) camera (not knocking that, still use my N90s and 8008s bodeis sometime) you'd want to finish the roll, and then just open the camera back and snip the film from the cassette -I'd assume anyway.

But as I recall, my Nikons don't just start rewinding on the last frame, I have to use the rewind buttons? Haven't used those for testing so can't recall, but in that case, you'd want to stop shooting before the last frame.

Thanks for the answer. With my camera it might be possible to gently lift the film off the pressure-plate and gently pull it back from the wind-on pulley feeling for the tab as each one comes up then cutting it.

My other worry is that in the total darkness I might not be able to feel for the blank frame in the middle and so place my tab on a "live" frame.

Still your method does ensure that you have four sections for development from one film

pentaxuser

 

[M Carter]

The blank frame's easy. Shoot your last bracket of a set, and advance one frame. On any SLR prism camera, the film plane is exactly centered under the eyepiece, so totally easy to find in the dark. And your strip of tape's a couple mm, your cut will be like a zillionth of a MM - horseshoes and hand grenades are fine here - you won't cut into a working frame. (Using small scissors was a night & day upgrade here though, much easier to cut in the dark!)

With my rangefinder, I just had to make sort of a mental note of where the center was, but of course, it's the center of the lens. Or you could stick a piece of tape on the back of the camera, above the door.

The hardest part of the process is getting a strip of 4 frames onto a metal reel... much as I love my Hewes reel, I collapsed my plastic 120 down to 35 and then it's a piece of cake to slip it into the feed slots.

When the roll is done, I don't rewind it - I just open the camera (in the dark), snip it at the cassette, and pull it from the wind reel. My metal 35's - minolta RF, Nikon FG, Old Canons - once you hit the rewind button, the spindle turns freely. never tried it with a more "modern" camera like an N90s, I don't know if those spindles are locked until you hit rewind. But you could snip at the cassette, close the back, and hit the rewind button, but do it with scrap film? I don't think the winding reel winds backwards though, I assume it just de-clutches and the spool-reel starts winding.

I also don't get too hung u on perfect handling - if I get a scratch, it's not like I want to make an art print of my test still life... "Styrofoam and Flannel Shirt with Gray Card, 2015, 20x24 silver gelatine print" doesn't sound too interesting to me...

 

[pentaxuser]

Thanks MCarter, some very helpful tips here

pentaxuser

 

[trythis]

To answer original post question:
http://www.digitaltruth.com/apps/mdc/mdc-faq.php

[h=2]I've noticed that some ISO listings have a dot next to them. What does this mean?[/h]

In cases where there is more than one suggested time/temp combination for the same film speed, this is indicated by a dot or series of dots after the ISO number. For example, you might see 400, 400., 400.. as options. Each of these is a different suggested time. The time listed without the dot is usually the standard recommended development time. The other times may differ in terms of temperature, agitation etc, so please check the notes and compare each time carefully to help determine the best one for your requirements.

I scanned the posts before mine and didn't see this referenced, doesnt mean it wasn't, just means I missed it.