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neil poulsen
23-Jun-2014, 08:41
I thought that I would do a sanity check; mine!

But before you render an opinion, let me explain . . .

I just completed a speed test for Ilford's HP5, and determined that the speed of my box of film is ASA 141, which is a half-stop better than ASA 100, and of course a half-stop worse than ASA 200.

Is this consistent with the results that others have obtained? Normally, I come up with ASA 200, so I guess it isn't so far off of typical. But, I thought that I would check.

I've accurately taken into account bellows expansion and actual shutter speed. My FB+F was 0.08, and my target was 0.18. I checked my densitometer with a Stouffer's standard that I keep on hand, and it's accuracy appears to be satisfactory.

StoneNYC
23-Jun-2014, 08:49
The actual speed of HP5+ is 400, ilfords speed is accurate, your tests must be off, or your qualifiers differ from ISO standards.

IF you're happy shooting it at such a speed, then do so... But that's way off the mark for me.

Ken Lee
23-Jun-2014, 09:18
This thread will likely grow to encompass the usual ping-pong game between those who use box speeds and those who don't.

That being said, you're still rather close to the usual results of those who don't use box speeds. If your prints are beautiful, then what's the worry ? After all, it's your water, thermometer, agitation, etc.

I presume your results are for N development. We know that effective film speed changes with expansion and contraction.

What developer by the way ?

ROL
23-Jun-2014, 09:19
I just completed a speed test for Ilford's HP5, and determined that the speed of my box of film is ASA 141, which is a half-stop better than ASA 100, and of course a half-stop worse than ASA 200.

The last time I tested, I was satisfied with 200. But, by all means keep testing – maybe you can get the accuracy to 141.4159, for a full measure of PI(e)! :D

StoneNYC
23-Jun-2014, 09:22
The last time I tested, I was satisfied with 200. But, by all means keep testing – maybe you can get the accuracy to 141.4159, for a full measure of PI(e)! :D

That would be EI 314.159 wouldn't it?

ROL
23-Jun-2014, 09:26
Touché.

IanG
23-Jun-2014, 09:31
Ken's right, many shoot HP5 at 200EI, tests involve equipment and other tolerances, like thermometers agitation etc.

I always shot HP5 at 200 but in Pyrocat I use box speed, I use practical tests rather than a Densitometer although I have acquired one this year after 45 years of photography.

Ian

RichardRitter
23-Jun-2014, 09:32
I have been using an ISO of 150 and it's producing great negatives. With great tonal range.

Read the fine print of the film manufacturer guild lines. It said subjected ratting.

Had a long talk with a film expert in the 80's from Polaroid. The listed film rating should be a starting point and then find what works for you. Different developers will give the film slightly different ISO ratings.

neil poulsen
23-Jun-2014, 09:45
Thanks for the input. 141.42135623730950488016887242097 it is, then.

Heroique
23-Jun-2014, 09:51
I just completed a speed test for Ilford's HP5...

Welcome to a tiny sub-set of forum members – the film speed testers.

Don't feel bad if no one agrees with your results.

Your glorious prints will win back their approval.

Drew Wiley
23-Jun-2014, 10:06
What on earth kind of developer are you using? I dev it in PMK, which is not exactly a high-ASA developer, and have been using full box speed (400) all along.

StoneNYC
23-Jun-2014, 10:43
I shoot it at 800 ;) haha :-p

Drew Wiley
23-Jun-2014, 11:14
What I find so odd about this is that I routinely cut the box speed of every other Ilford film in half; it's only HP5 that I shoot at full speed. Same meters, same dev
strategy, same cameras.

Harold_4074
23-Jun-2014, 12:04
Drew, interesting observation. I also use PMK, metering FP4 at 80 but HP5 at 320. Back when I used Plus-X and Tri-X, they were also metered at half box speed, which seems to be typical for PMK. For some reason, HP5 doesn't mess up the upper mid tones when slightly underexposed the way the other films do.

Neil: you are comparing a calculated 140 versus 200, presumably based on instrumental data rather than the printing qualities of the resulting negatives, so the above comment may not be as relevant to you. But do you have a reference sample of film against which to confirm your processing? Kodak process control strips were carefully manufactured and handled for precisely the reason that it is not trivial to manage consistent development without some sort of reliable reference.

Drew Wiley
23-Jun-2014, 12:15
HP5 has a relatively long toe; so I don't particularly care for it in high-contrast situations to begin with. But it can work wonders in certain kinds of lighting, and I like
the speed for 8x10 use. Rarely shoot it in any format smaller than that. I should qualify this by stating that I like HP5 negs a bit "thick" in order to accentuate the
midtone microcontrast and edge effect this film renders so nicely. But a slight overdevelopment like this can render the highlights difficult to print. So the only way
I can have my cake and eat it too is to use a supplementary silver mask, even with today's excellent VC papers. Yet the net result of this extra effort can be something quite special. Otherwise I've standardized on TMY400, which I find more versatile; and it will dig way down into the shadows and resolve values there in
a way HP5 simply can't. Having this option, HP5 will still remain one of my favorite films for 8x10. It does have a special look.

Jim Noel
23-Jun-2014, 12:43
You are not exposing at ASA 141. You are exposing at ASA 400, with an EI of 141.
Something is off in your system. This could be your meter, your shutter speeds, or your processing.
This said, if it works for you , use it.

Brian C. Miller
23-Jun-2014, 12:46
But do you have a reference sample of film against which to confirm your processing? Kodak process control strips were carefully manufactured and handled for precisely the reason that it is not trivial to manage consistent development without some sort of reliable reference.

Unique Photo still carries color control strips (link (http://www.uniquephoto.com/control-strips/)), but did anyone ever make B&W control strips?

dsphotog
23-Jun-2014, 14:03
Thanks for using ASA, it's what my camera's & meter's have on them.

Peter Gomena
23-Jun-2014, 15:02
Kodak manufactured B&W film strips. We used them when I was a first-year student at Brooks Institute of Photography, which was more than 20 years ago.

Bill Burk
23-Jun-2014, 18:14
I thought that I would do a sanity check; mine!

But before you render an opinion, let me explain . . .

I just completed a speed test for Ilford's HP5, and determined that the speed of my box of film is ASA 141, which is a half-stop better than ASA 100, and of course a half-stop worse than ASA 200.

Is this consistent with the results that others have obtained? Normally, I come up with ASA 200, so I guess it isn't so far off of typical. But, I thought that I would check.

I've accurately taken into account bellows expansion and actual shutter speed. My FB+F was 0.08, and my target was 0.18. I checked my densitometer with a Stouffer's standard that I keep on hand, and it's accuracy appears to be satisfactory.

Do your tests include a measure of contrast? Just curious if you judge film speed at the same development time that reaches 0.62 contrast. Or do you develop to Zone System classic "N" time which gives you a certain Zone IX density calibrated to your printing paper.

And also curious if you are doing classic Zone System speed test, where you meter and then stop down to Zone I.

The answer to those two questions can easily account for a stop from Box Speed. Then all that would have to happen for you to "lose" another half stop, is some deviation like choice of developer, minor processing mistakes like time and temperature...

In other words you are sane, it's not uncommon to find personal speeds that are different than manufacturer rated speed.

Andrew O'Neill
23-Jun-2014, 22:14
I shoot HP5 at 250 with most developers, but I remember using a developer (can't remember which one) back in the 90's where I had to use an EI of 160. You have to find what works. Not surprised in the least if EI 141 worked for you.

neil poulsen
24-Jun-2014, 03:21
Do your tests include a measure of contrast? Just curious if you judge film speed at the same development time that reaches 0.62 contrast. Or do you develop to Zone System classic "N" time which gives you a certain Zone IX density calibrated to your printing paper.

And also curious if you are doing classic Zone System speed test, where you meter and then stop down to Zone I.

The answer to those two questions can easily account for a stop from Box Speed. Then all that would have to happen for you to "lose" another half stop, is some deviation like choice of developer, minor processing mistakes like time and temperature...

In other words you are sane, it's not uncommon to find personal speeds that are different than manufacturer rated speed.

The classic Zone System speed test. I metered at ASA 400, and then stopped down to a Zone I. Thereafter, I took three more exposures, opening the aperture a half-stop for each. It's for the last sheet of film that I reported data (FB+f of 0.08 and 0.18 for my target reading, which of course is 0.1 above FB+f). I'm using D76 as a developer, switching from ID-11. So, I'm redoing my Zone system calibrations for the first time in years.

This is the first time that I've used my Zone VI modified meter for testing, which might account for the additional half-stop loss of speed. (Compared to my usual results of ASA 200.) I use daylight corrected bulbs to illuminate my test target, since I suspect that pan-chromatic b&w film is daylight corrected. If my meter performs as purported, I believe it may read the blue a little higher, since blue appears lighter in b&w prints. Thereby, this will close the f-stop a little for a Zone I, and require a little lower ASA to reach the 0.1 above FB+f standard.

IanG
24-Jun-2014, 03:30
The classic Zone System speed test. I metered at ASA 400, and then stopped down to a Zone I. Thereafter, I took three more exposures, opening the aperture a half-stop for each. It's for the last sheet of film that I reported data (FB+f of 0.08 and 0.18 for my target reading, which of course is 0.1 above FB+f). I'm using D76 as a developer, switching from ID-11. So, I'm redoing my Zone system calibrations for the first time in years.

This is the first time that I've used my Zone VI modified meter for testing, which might account for the additional half-stop loss of speed. (Compared to my usual results of ASA 200.) I use daylight corrected bulbs to illuminate my test target, since I suspect that pan-chromatic b&w film is daylight corrected.

Daylight corrected bulbs are not a good substitute for daylight, Ilford used to publish ISO speeds for daylight and artificial light, 400 daylight, 200 artificial light for HP5 so you've not run a valid test except for shooting with those particular lamps.

Ian

w5ami
24-Jun-2014, 07:08
The classic Zone System speed test. I metered at ASA 400, and then stopped down to a Zone I. Thereafter, I took three more exposures, opening the aperture a half-stop for each. It's for the last sheet of film that I reported data (FB+f of 0.08 and 0.18 for my target reading, which of course is 0.1 above FB+f). I'm using D76 as a developer, switching from ID-11. So, I'm redoing my Zone system calibrations for the first time in years.

This is the first time that I've used my Zone VI modified meter for testing, which might account for the additional half-stop loss of speed. (Compared to my usual results of ASA 200.) I use daylight corrected bulbs to illuminate my test target, since I suspect that pan-chromatic b&w film is daylight corrected. If my meter performs as purported, I believe it may read the blue a little higher, since blue appears lighter in b&w prints. Thereby, this will close the f-stop a little for a Zone I, and require a little lower ASA to reach the 0.1 above FB+f standard.

I would strongly suggest using real daylight if at all possible. A good evenly overcast day works great, but a open area with blue skies overhead and no direct sun works even better. All assuming you are film testing for mostly outdoor photos.

Brian

ic-racer
24-Jun-2014, 07:50
I thought that I would do a sanity check; mine!

But before you render an opinion, let me explain . . .

I just completed a speed test for Ilford's HP5, and determined that the speed of my box of film is ASA 141, which is a half-stop better than ASA 100, and of course a half-stop worse than ASA 200.

Is this consistent with the results that others have obtained? Normally, I come up with ASA 200, so I guess it isn't so far off of typical. But, I thought that I would check.

I've accurately taken into account bellows expansion and actual shutter speed. My FB+F was 0.08, and my target was 0.18. I checked my densitometer with a Stouffer's standard that I keep on hand, and it's accuracy appears to be satisfactory.

Most would interpret that as an "exposure index" test. It is not clear what you are using as a target, but if you can have the lens focused at 'infinity' you won't have to bother with a bellows extension calculation.

ic-racer
24-Jun-2014, 07:53
Unique Photo still carries color control strips (link (http://www.uniquephoto.com/control-strips/)), but did anyone ever make B&W control strips?

Most people make their own B&W control strips. You can cobble together a simple sensitometer without too much trouble.

Mark Sampson
24-Jun-2014, 11:45
Kodak made b/w control strips- they were very useful when I operated replenished sink-line processes. Not sure if they still do, though. I've never heard of anyone making their own b/w control strips. I suppose you could... but making them accurate and consistent enough to be valuable might well be more effort than it would be worth.

ic-racer
24-Jun-2014, 14:22
117347
Critical sensitometry requires control of image latency, that is unavailable in these pre-made strips. "Development Process Control" strips like these that are made 'on-site' with a sensitometer have some advantages over the pre-made ones, such as reduced cost, improved obtainability, control of latency, control of film batch and type, etc.

Bill Burk
24-Jun-2014, 21:19
The classic Zone System speed test. I metered at ASA 400, and then stopped down to a Zone I. Thereafter, I took three more exposures, opening the aperture a half-stop for each. It's for the last sheet of film that I reported data (FB+f of 0.08 and 0.18 for my target reading, which of course is 0.1 above FB+f).

OK, then your speed is 142.2623528 according to my calculations. As others have pointed out, this is a "Blue Tungsten Bulb" speed.

That's -2.25 in log Meter Candle Seconds (arithmetic 0.005623413 Meter Candle Seconds).

Take 0.8 divided by 0.005623413 and you get the speed I calculated.

I would have been pleased to quote a time in terms of Pi or Square Root of 2, if that's how it would have worked out. But I don't think those familiar constants contribute to the right answer in this case.

neil poulsen,

The fact you obtained a "Blue Tungsten Bulb" speed shouldn't be too disconcerting. It's probably going to come in handy when you do some copy work. Then that's the right speed to use.

But for daylight landscapes, I think you might be better off assuming your old favorite speed "200" still applies.

bbuszard
25-Jun-2014, 11:17
But for daylight landscapes, I think you might be better off assuming your old favorite speed "200" still applies.

Perhaps, but my tests in daylight have produced results similar to Neil's. I shoot HP5+ at 160 (unless I'm shooting handheld). With FP4+, oddly enough, I can shoot at box speed. Same process for both films, using Xtol 1:1 at 24C.

jerrybro
25-Jun-2014, 20:09
Neil, congratulations. You have found your personal speed for that film in that developer using specific techique. For TMY in one developer I ended up at 160. So? If that allows you to get predictable results nothing else matters.

"If you do this you cna get more speed."
"If you try this developer you can get more speed."
"I do it this way and get a higher ISO."

If you get what you want in the final result nothing else matters.

Cheers

neil poulsen
26-Jun-2014, 07:22
Perhaps, but my tests in daylight have produced results similar to Neil's. I shoot HP5+ at 160 (unless I'm shooting handheld). With FP4+, oddly enough, I can shoot at box speed. Same process for both films, using Xtol 1:1 at 24C.

That's interesting about FP4. I'm itching to give this film a try. If so, I may not have to take too much of a hit in speed.

My film speed test target is about 6" in diameter cut in a largish sheet of plywood. I place a sheet of translucent white plastic against this and follow with a sheet of frosted glass 3/4" behind that. I illuminate this target from behind with two blue bulbs. I can change the intensity of the target by varying the distance between the bulbs and the target. (Or, by turning off one of the light bulbs.)

djdister
26-Jun-2014, 07:42
Given your results for HP5, you should definitely consider either FP4 or Delta 100.

Brian C. Miller
26-Jun-2014, 07:49
Neil, what is your take on Paul Wainwright's zone method? (PDF link (http://www.paulwainwrightphotography.com/biblio_files/use_your_eyes.pdf))

Stephen Benskin
28-Jun-2014, 18:05
117499

jnantz
28-Jun-2014, 18:23
I thought that I would do a sanity check; mine!

But before you render an opinion, let me explain . . .

I just completed a speed test for Ilford's HP5, and determined that the speed of my box of film is ASA 141, which is a half-stop better than ASA 100, and of course a half-stop worse than ASA 200.

Is this consistent with the results that others have obtained? Normally, I come up with ASA 200, so I guess it isn't so far off of typical. But, I thought that I would check.

I've accurately taken into account bellows expansion and actual shutter speed. My FB+F was 0.08, and my target was 0.18. I checked my densitometer with a Stouffer's standard that I keep on hand, and it's accuracy appears to be satisfactory.

neil

have you used this film in a non-controlled-atmosphere yet ..
i mean in a non film test / situation shooting outside
or wherever / whatever you like to shoot ?

and did your "real life" ( non-controlled-lab ) results
jive when you exposed your hp5 at iso 141 with your
processing-situation ? or was your film over / under exposed ?

john

Regular Rod
29-Jun-2014, 04:33
Doesn't all this depend on what you choose to meter on in the subject?

RR

IanG
30-Jun-2014, 13:46
Doesn't all this depend on what you choose to meter on in the subject?

RR

When you do a speed test you use a reference point (it might be an 18% grey card) and you work from there. It's slightly different to metering an image in real life, which John is alluding to.

There's no totally definitive method, The Minor White/Adams method of Zone System testing differs slightly from the British approach used by John Blakemore, Peter Cattrell, Fay Godwin, John Davies etc - we tend to print slightly a bit flatter in the UK, with a longer tonal range. Actually if you look at Ansel Adams work his later prints (even off early negatives)n were much more tonal.

Ian

Kevin J. Kolosky
2-Jul-2014, 10:19
best thing to do now is go out and shoot some long scale, short scale, and medium scale subjects, using your tested ISO and a few other ISOs and then contact print all of them at the same time, which would be the time for the film base to just turn black. develop all the same. see what you have and go from there.

neil poulsen
2-Jul-2014, 15:49
Neil, what is your take on Paul Wainwright's zone method? (PDF link (http://www.paulwainwrightphotography.com/biblio_files/use_your_eyes.pdf))

I read over the portion that discussed exposure index. One thing, he presents a method that doesn't require a densitometer. Personally, I HAVE TO HAVE a densitometer. If I didn't have one to do calibrations, I'd start twitching. In full disclosure, I'm a statistician, so I LOVE DATA. And, my densitometer isn't that great. I spent $100 for it years ago, and until I received it, I wasn't that certain that it worked. But from an old Stouffer test negative that I have, it gives me fairly accurate results in the lower regions, and it gives me comparative values above that. By comparative values, I need to only be confident that densities are the same in two different negatives.

But also, I don't think that it was without consideration, that Ansel Adams recommended the 0.1 density units above FB+f. I'd be interested in the views of others on this; but, I think that at stake in selecting this standard (0.1) are both detail in the shadows and detail in the highlights. The higher this number, the less room at the top for the highlights. So, the 0.1 standard is a compromise between room at the top and room at the bottom. In recommending an ASA of 200, Wainright isn't that far off. That's what I typically get. But, I think that it's best to have data to know for sure. In this case, I believe that my lower than typical results can be traced to a combination of using blue bulbs and using a Zone VI modified meter. Apparently, my testing with data took this into consideration.

As for determining development times, he uses a method that lends itself to visual examination. For example, to get an N-1 development time, he would lower the development time until he sees detail in a Zone IX exposure.

I would call this an "absolute" approach, where mine is more a "relative" approach. For the same result, I would first determine an enlarger exposure time for maximum paper black (as Wainright does), and then use visual examination to select a film density that gives me a Zone VIII that I like. This would by my "N" development. (I use Zone VIII for an "N" development; Ansel Adams recommended Zone VII for an "N" development.) Thereafter, I would use comparative readings to find a Zone IX film density that gives me this same value for an N-1 development. And, so on and so forth.

In summary, I would say that Wainright's approach, and his recommendation of using ASA 200 for an ASA 400 film, is based on a solid understanding of how B&W film behaves. His "absolute" approach lends itself to visual examination, where one might not have a densitometer. But, it's a bit squishy for me and includes sources of variability that I can avoid using a densitometer. Besides, I LOVE DATA!

neil poulsen
2-Jul-2014, 16:10
neil

have you used this film in a non-controlled-atmosphere yet ..
i mean in a non film test / situation shooting outside
or wherever / whatever you like to shoot ?

and did your "real life" ( non-controlled-lab ) results
jive when you exposed your hp5 at iso 141 with your
processing-situation ? or was your film over / under exposed ?

john

Of course, the real test is in how prints come out. The reason I migrated to using blue bulbs, was because I wasn't getting the results I wanted in the field.

neil poulsen
2-Jul-2014, 16:16
Doesn't all this depend on what you choose to meter on in the subject?

RR

Yes. And, A.A. gave us a strategy by which to decide what to meter in a scene. Meter as a Zone III in the scene the darkest area in which we wish to retain detail shadows. Also meter as a Zone VIII (for me) the lightest area in which we wish to regain detail in the highlights.

Bill Burk
2-Jul-2014, 22:42
Yes. And, A.A. gave us a strategy by which to decide what to meter in a scene. Meter as a Zone III in the scene the darkest area in which we wish to retain detail shadows. Also meter as a Zone VIII (for me) the lightest area in which we wish to regain detail in the highlights.

You are right, when you spotmeter a shadow and then place the reading on a shadow zone, you might place it on Zone II (Minor White), Zone III (Common Practice) or Zone IV (Bruce Barnbaum). Makes a big difference in exposure. Probably does not make a big difference in results... but whenever you work towards a personal EI... You have to make up your mind first... which Zone you will place the shadows on...

Drew Wiley
3-Jul-2014, 08:59
It's really the shape of the toe, and not box speed, in relation to the all the other variables, which determines where you place your deepest shadows. Who preached this of that as some kind of hard rule is basically meaningless. Films differs. There are film and developer combinations where I can easily get crisp shadow separation clear down to Zone 1 or even 0, or at the other extreme, something like PanF, which has a very brief straight line, and I do need place it way up there on Z III. And everything is ultimately decided by your personal aesthetic. So there Zone system is not meaningfully a religion with an alleged Pope, but more like a big rubber band you stretch to accommodate your own objectives. And the only way to determine this is to practice shooting, developing, and printing.

Bill Burk
3-Jul-2014, 10:22
It's really the shape of the toe, and not box speed, in relation to the all the other variables, which determines where you place your deepest shadows.

True, when you want the least exposure you use a certain amount of the toe and the shape is important.

I was just stating the obvious that you can use box speed and place your shadows on Zone IV, or use half box speed and place shadows on Zone III and get the same aperture and f/stop setting on the camera...

So how you meter and calculate exposure is a very important part of the personal film speed determination for big, obvious reasons. Because picking one Zone or another for shadow placement, is as big a change as picking double or half the exposure index.