Testing film with step wedge?

[menglert]

I don’t have access to a densitometer to test my films with, and am looking for another option… Can I purchase a step wedge like the Stouffer 21 step, and visually match my films middle gray to that of the step wedge?

 

[Bruce Osgood]

I don’t have access to a densitometer to test my films with, and am looking for another option… Can I purchase a step wedge like the Stouffer 21 step, and visually match my films middle gray to that of the step wedge?

In the ARTICLES/HOW TO section of the COMMUNITY listings there is an article written by noseoil on just that:

(there was a url link here which no longer exists)

 

[Ray Heath]

here's a thought, take some photos at the manufacturers recommended ISO/dev combo and see what happens

 

[Bruce Osgood]

Or, for less money than a step wedge, you can get the "Film Test Kit" from www.circleofthesunproductions.com. It has all you need to test for both proper ISO and proper development time without a densitometer. It can be reused forever, and has comprehensive instructions.

Good luck!

Bruce Barlow

Do you know what comprises the 'kit'? I looked at the site and there is no detail as to what the kit is.

 

[ronlamarsh]

Testing

My recomendation is get the step wedge you'll use more than once and they don't wear out. You can do it without its just more labor intensive. In Bruce Barnbaums book"The art of Black and White Photography" he gives a very easy procedure for this without a step wedge or densitometer.
Shoot a number of exposures of a blank subejct evenly lit at the manufacturers ISO and above and below. Process per manufacturers directions or your own personal preference. Find the exposure that gives just a hint of density above B+F take that ISO setting and cut it in half and that is your ISO. I have used this many times and it is just as accurate as using a densitometer. Then using this ISO , shoot a Zone 5 and zone 8 exposure develope and print at you standard (max blk) printing time. check the Zone 5 against a grey card and the Zone 8 against white paper preferably you'll leave part of the zone 8 print unexposed for this. Even with a densitometer I end up at this point since the eye is often just as accurate.....it won't discern between a negative density change of .05 but if you can't visualize it in the print it doesn't matter.

 

[menglert]

Thanks for all the responses.

I think I will go with the step wedge because it can be used for other things in the future. But, I would like to know what the kit mentioned above includes.

Does anyone here have experience with the kit?

Regards,
Martin

 

[lowellh]

I like your thought Ray!

 

[Amund]

here's a thought, take some photos at the manufacturers recommended ISO/dev combo and see what happens

Couldn`t agree more. Last year I did the "film and developer dance" trying a bunch of differnt film/developers at various ISO etc. Lately I`ve been using Tri-X at box speed in DDX/T-Max at manufacturers recommended time. Best negs ever. Go figure....

 

[Ray Heath]

yeh guys, you don't need to 'go figure', some expert has already figured it to pretty close, all you need do is tweak from there

 

[BradS]

yeh guys, you don't need to 'go figure', some expert has already figured it to pretty close, all you need do is tweak from there

Hmmm, maybe that's why the stuff in the yellow box costs a little more?

 

[dancqu]

I don’t have access to a densitometer ...

B&H have for $24.50 the Ilford EM-10 enlarger exposure
meter. It is a very small spot spot meter which in effect
measures the light intensity falling upon a minute area of
the easel. I've calibrated my EM-10 against a 21 step
wedge. Under exact same conditions as calibration
the densities of any small areas of any negative
can be determined. Use as a densitometer.

The EM-10 is worth while having for it's usual purpose.
I'll likely submit an article describing the use of the
EM-10 as a densitometer. Dan

 

[raucousimages]

Less time testing = more time shooting. I think too many shooters are trying to find magic bullets by testing the hell out everything. So what if you find out the exact ISO of a film. That will change with every developer. Or are you going to test every possible film developer combo like some others in APUG? Get close, Shoot, learn to print. You can become obsessed with testing.

 

[Kino]

yeh guys, you don't need to 'go figure', some expert has already figured it to pretty close, all you need do is tweak from there

Pardon me if I choose NOT to accept those results and do my own testing!

For myself, I find I need to tear it all apart and see how it really works (to the best of my ability) and then proceed...

Besides, it is gratifying. Productivity is all relative, eh?

 

[Bruce Appel]

I test, and usually end up finding I am not far off from what the manufacturer recomends. For me, the value is that I am testing my whole proccess- if I get some numbers that are way off from the manufacturers recomendations, I know somewhwere I have screwed something up.
I do not test a lot, usually just when trying a new film/developer/paper combo for the first time, and I try to avoid that. I want consistancy, so that I know with some degree of certainty that I am going to get what I want when I trip the shutter.
I recently got an em10, and I can see the value of using it as a densitometer, something I have never had. I would love it if you wrote an article about it Dan.

 

[BBarlow690]

Thank you for pointing out my scant description of the Film Test Kit at www.circleofthesunproductions.com. I'll fix it on the site.

The kit contains:

- Two .1 ND filters (not optical quality, one to use and one to keep in case you lose the first one). For film speed, you lay the filter on unexposed-but-developed film and compare it to test exposures. The matching test exposure is easy to see.

- An example of Zone VIII vs. paper base. In our experience at Fine Focus Workshops and with my other students, folks don't necessarily know what to look for. The kit has an example.

- Comprehensive instructions on how to make and evaluate exposures, how to make Proper Proofs, a short explanation of the Zone System ideas from which we can extract a common vocabulary (see how carefully I phrased that?), and a method of exposure in the field that, once tests are done, has never failed me nor anyone I know who uses it. If you have the right film speed, the right development time, and the right proofing time, you can rule the world.

Last time I checked, a .1ND filter cost more than the kit (sadly, Kodak no longer makes the cheap ones), and is overkill for what you need. Folks are offering to read tests with densitometers for anywhere from $7 to $25. The Film Test Kit is reusable forever, and your evaluations will be every bit as accurate as the experts. You don't need a densitometer.

I've used the kit for Pyro staining film developers, and for negatives intended for Azo Grade 2. It works by tuning your equipment, materials, and processes to each other, rather than relying on someone else's opinion of what's "right."

By the way, if you visit the site, Richard Ritter's video on Camera Repair in the Field with Richard Ritter has gathered praise from many. If you're an LF user, you want it just to watch the opening, where Richard smashes a field camera and then fixes it on the spot.

Hope this clarifies things a bit. Again, thanks for pointing out my taciturn New England verbage on the site.

Use the kit, get testing out of the way, and spend your time making beautiful images! I agree with those who say we have too much testing and not enough photography, and I'm as guilty of that as anyone.

 

[Bruce Appel]

The kit works, I have used it.There are many paths to the Buddha.

 

[Paul Howell]

I am going to order a kit and see if it will work for me, my current system does work but it is time consuming.

 

[Bruce Appel]

It all takes time, and I don't find it terribly enjoyable, but alas somewhat neccassry. Once I find a combo that works I tend to stick with it. Years ago after lots of testing, I settled on apx100 in rodinol. That was all I shot until apx went away, and I have since been doing a lot of testing and experimenting to get a replacement.
Having a good repeatable method may be more important than ever in this age of rapidly changing product supply.

 

[pentaxuser]

B&H have for $24.50 the Ilford EM-10 enlarger exposure
meter. It is a very small spot spot meter which in effect
measures the light intensity falling upon a minute area of
the easel. I've calibrated my EM-10 against a 21 step
wedge. Under exact same conditions as calibration
the densities of any small areas of any negative
can be determined. Use as a densitometer.

The EM-10 is worth while having for it's usual purpose.
I'll likely submit an article describing the use of the
EM-10 as a densitometer. Dan

It would certainly be useful for me,Dan and I suspect a few others. I inherited an EM10 as part of a secondhand Darkroom purchase which I don't use as I have a Phillips Analyser/timer but I'd certainly give it a go to test film speed and development.

I look forward to it.

pentaxuser

 

[johnnywalker]

The EM-10 is worth while having for it's usual purpose.
I'll likely submit an article describing the use of the
EM-10 as a densitometer. Dan

Thanks, I'd like to read that.

 

[ronlamarsh]

Testing

Yes it takes time to test and it is not very enjoyable, but if you really don't know how the film/dev/paper/dev combination works or is capable of then results will be less than consistent. You can waste a lot of paper trying to get that print just right when if your negatives aren't consistent.
I advocate a minimum amount of testing since such activities take away from shooting time and it is painful. I use only one kind of film, paper,paper dev and 2 film developers. This limits testing to a minimum and saves me a lot of paper in the printing stage. When I meter a scene and place a value on a particular Zone I know pretty closely what that will look like on the paper and do a lot less fussing around in the printing stage.

 

[Paul Howell]

I test because I use a lot of different cameras, 35 to 4X5 and each camera is rated at different film speeds. For that matter I rate each of my 4X5 lens at different film speeds. I still use 5 films, but over the past years I have narrowed by film developers down to 3.

 

[Daniel_OB]

film test is a must for serious photog. It is a must because he want to know what he is doing. Using densitometer is the most accurate but still far from to be really acurate. One have to include his whole photo system into film testing (on speed and developing procedure). The reason is that camera (or lens) shutter has an error of about 1/3 on "good" camera, apperture has a n error about 1/3 too on "good" lens, densitometer has an error, reading has an error,... So the only reliable system is, again, to reinvestigate film testing in the way that actual and whole photo system of one particular photog is included into testing. Such a system do exist but is still not published. Also that testing sytem has no additional cost (as e.g. densitometer, wedges,...) for it includes ONLY stuff photog already use and allow that the whole test procedure is done in about 30 min once mastered. While it come out do trickery you know. No advantage of having densitometer over "wedge" for they both produce "errors".

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