Personal EI or film speed test procedure

[Down Under]

I've never owned a step wedge, nor have I even seen one. So that leaves me out.

For me the best test, I reckon, is the simplest one ever devised (by me, tho' I would never claim to be its original creator, surely others have done this, long before I came along and bought my first Yashica TLR. Some guy named Ansel, I think, thought it up on or about 1940, tinkered with it a bit, expanded it, and made his reputation out of it, along with LF snapshots of Yosemite. Obviously, it must work.).

First, you find a brick wall. Then you wait for an overcast but bright day.

Put your camera (loaded with film, of course) on a tripod and expose as follows -

Normal exposure - then reverse, three steps (-0.3, -0.7, -1.0), then forward, three steps (+0.3, +0.7, +1.0).

Process the film as you always do. Normally. Evaluate the results.

Next, repeat the process on a sunny day. As per above.

By which time you may have figured out that something seems to be wrong with your processing workflow. Especially if you use replenished developer, or you home-brew using chemistry not intended for film developers (supermarket laundry borax instead of sodium metaborate, etc etc). So you test your developer by reshooting the lot, dividing the rolls into three equal parts, and developing for 0.5 (half) the time, 1.0 (normal) time, and 1.5 (normal and half again).

Eventually you go insane from it all - and the problem goes away by itself.

 

[ic-racer]

Over the years, I've re-though my film-speed testing.

First, how you determine your personal E.I. depends on how you meter. If you're a Zone System user using a spot meter to meter and place shadow values, you'll end up with a different E.I. than if you shoot 35mm using an in-camera matrix meter, etc., etc.

Also, there are different approaches to the whole "finding your personal E.I." process. Some like to nail everything down with step wedges, densitometers and plotted graphs before they make a photograph of anything important, some like to just go out and make pictures and adjust things on the fly.

I've done all the testing, exposing film in 1/3 stop intervals to a gray card then reading densities, making proper proofs, etc., etc.

I no longer think all that work is necessary. Remember, there is a rather large window of exposure and development for black-and-white negative films that will still allow you to make an excellent print. You only need to hit the window.

So, if you plan on basing your exposure on a shadow value à la Zone System and plan on making prints in the darkroom here's my advice: Rate your film at 2/3-stop slower than box speed (for starters). Make photographs, keeping careful notes about the shadow value you used to base the exposure on and what Zone you placed it on as well as where the other values in the scene fall (e.g., highlight value in Zone VIII or wherever). Don't worry about N+ or N- developments to start with. Make negatives and develop them according to manufacturers' recommendations (or a reliable recommendation for your film/developer combination if there isn't one from the manufacturer). Then, make "proper proofs" of your negatives, i.e., a proof print where the black of the clear film rebate is just a tiny, tiny bit less black than the maximum black the paper is capable of. Look at those proofs and examine the shadows, highlights and overall contrast carefully.

Then, make adjustments to your starting E.I. and development time as follows: (This may sound familiar...)
-For normal scenes, if your prints consistently have too-dark shadows, rate your film a bit slower.
-For normal scenes, if your prints are consistently to contrasty (i.e., the highlights are too bright and without detail), then reduce your development time 10%. Increase development time 10% if the highlights are too dull and dark.
-Repeat until you zero in on an E.I. and development time that allows you to print your normal scenes at a medium contrast setting (e.g. a #2.5 filter or thereabouts)
(Note, the above is for "normal" scenes, in which Zone III is a textured black and Zone VIII is a textured white).

If you want to explore N+ and N- developments (only really practical if you use sheet film), then do the same for low-contrast and high-contrast scenes (do read about where the highlight Zones need to be for each, e.g., for N-1, Zone IX is the one that should print as a textured white). With today's VC papers, this is less important.

If you plan on using an in-camera meter, then the approach is different. Rate your film at box speed (for starters), go out and make pictures. Print those pictures as well as you can and then make adjustments as follows:
-For normal scenes, if your prints consistently have too-dark, featureless shadows, rate your film a bit slower.
-For normal scenes, if your prints are consistently to contrasty (i.e., the highlights are too bright and without detail), then reduce your development time 10%. Increase development time 10% if the highlights are too dull and dark.
-Repeat until you zero in on an E.I. and development time that allows you to print your normal scenes at a medium contrast setting (e.g. a #2.5 filter or thereabouts)
-Plan on using the leeway VC paper offers to deal with scenes of different contrast.

Best,

Doremus

Nice summary, nothing to add.

 

[Stats]

When testing for your personal EI keep in mind that you are not testing the film, you are testing your equipment, specifically your light meter. I have two Pentax digital spot meters which I use for large format photography. One meter is set at 200 asa for Tri x, the other is set at 320asa. Both meters give the same readings.

 

[Stephen Ryde]

This is an eye opener for me.
I had no idea that the system I use to meter ie: Zone or non Zone, determines my camera metering settings.

I always use the Zone system and a hand held meter, none of my cameras have 1/3 stops only 1/2 stops

My conclusion from all this information?

Set my hand held meter to 2/3's box speed, place the shadows in my desired Zone, set my camera to the metered settings, if the settings can't be set to the metered settings overexpose to the next closest setting.

Am I getting close?

Now, when I develop the film, where should I start with my development time so I can place my highlights where they need to be?
Do I develop at the 2/3 box speed?
I know I have to print the negative so i can fine tune my development time.

Whew

Stephen

 

[JerseyDoug]

This is an eye opener for me.
I had no idea that the system I use to meter ie: Zone or non Zone, determines my camera metering settings.

I always use the Zone system and a hand held meter, none of my cameras have 1/3 stops only 1/2 stops

My conclusion from all this information?

Set my hand held meter to 2/3's box speed, place the shadows in my desired Zone, set my camera to the metered settings, if the settings can't be set to the metered settings overexpose to the next closest setting.

Am I getting close?

Now, when I develop the film, where should I start with my development time so I can place my highlights where they need to be?
Do I develop at the 2/3 box speed?
I know I have to print the negative so i can fine tune my development time.

Whew

Stephen

When I start using a new metering method, or a new film, or a new developer, or any combination of the above, I always start with the film and developer manufacturers recommended development time if they agree or with the average of the two if they don't agree.

 

[Doremus Scudder]

This is an eye opener for me.
I had no idea that the system I use to meter ie: Zone or non Zone, determines my camera metering settings.

I always use the Zone system and a hand held meter, none of my cameras have 1/3 stops only 1/2 stops

My conclusion from all this information?

Set my hand held meter to 2/3's box speed, place the shadows in my desired Zone, set my camera to the metered settings, if the settings can't be set to the metered settings overexpose to the next closest setting.

Am I getting close?

Now, when I develop the film, where should I start with my development time so I can place my highlights where they need to be?
Do I develop at the 2/3 box speed?
I know I have to print the negative so i can fine tune my development time.

Whew

Stephen

Stephen,

You are more than close IM-HO Yes, for starters, set your meter to 2/3-stop slower than box speed. I assume that's what you mean with "2/3 box speed" - if not, then you should be aware that each film-speed number is 1/3-stop away from the next. So, if you have an ISO 400 film, you'd move down two numbers, i.e., pass 320 and set your meter to 250. Does that make sense?

Once you've done that, just meter and place the shadow in your desired Zone and err on the side of overexposure if you can't apply the exact setting. The difference between 1/3-stop and 1/2-stop is only 1/6-stop - Nothing to worry about with b&w negative film (which I assume we are discussing here).

As for developing: There's really no such thing as "developing for 2/3-stop slower than box speed." I know that a lot of amateurs talk about "developing a stop slower or faster" or whatever, but things really don't work that way.

The amount of developing determines the contrast gradient on the negative, that is, the amount of density difference per extra stop of exposure. So, what you are after really is a development time that allows you to print the highlights from a scene with a "normal" subject brightness range (SBR) at a "normal" contrast setting on VC paper (that would be with a #2-#3 filter).

The manufacturer has tested developers with their film and arrived at a good starting point. You should use that first and then only deviate once you feel the need. If you're using a film/developer combination that neither the film or developer recommendations list, then check the Massive Development Chart online or inquire here for starting points. Note that the way you develop makes a difference in the time (tray, tank, rotary, etc.)

Then, to test your system make a few proper proofs. That's a print made at a middle contrast setting and exposed at the minimum time it takes for the black from a clear area of the negative like the rebate around the image to be rendered really, really close to maximum black on the paper. The way to do this is to make a test strip of the negative, leaving a bit of empty space at the edge of the negative for light to strike the paper without passing through the negative. You can then compare the black of the rebate and the black of the area exposed without the light passing through the negative. Evaluate the test strip when dry and in "normal" lighting for exhibiting prints. When in doubt, err on the side of the shorter exposure.

Once you have your proper proof exposure, proof a few negatives and see what they look like. If everything is overall way too dark, you've likely chosen the wrong proofing time. However, if your shadows look close to where you want them, you're on the right track. Now examine the highlights: If they are consistently too dark for "normal" scenes, your film developing time is too short, and vice-versa.

Similarly, if you are getting good blacks in really clear areas of your negative, but the shadows are still to dark, then you should rate your film slower and vice-versa.

Keep refining as you go. Remember, you've got lots of leeway with VC paper to deal with scenes with more or less SBR. The trick is to find the sweet spot for developing time that allows you to print the extremes of the things you photograph. If you consistently find that you're using the #5 filter or the #00 filter a lot, then adjust your developing time so that things are closer to whatever is the middle for you.

If you use sheet film, you can try exploring longer and shorter development times for scenes with lower and higher SBRs, respectively. Add 20% to your "normal" developing time for a starting point for N+1; subtract 20% for N-1. Repeat the proper proof tests for these times to refine.

Hope this helps,

Doremus

 

[Stephen Ryde]

When I start using a new metering method, or a new film, or a new developer, or any combination of the above, I always start with the film and developer manufacturers recommended development time if they agree or with the average of the two if they don't agree.

Awesome JerseyDoug thank you

 

[Stephen Ryde]

Stephen,

You are more than close IM-HO Yes, for starters, set your meter to 2/3-stop slower than box speed. I assume that's what you mean with "2/3 box speed" - if not, then you should be aware that each film-speed number is 1/3-stop away from the next. So, if you have an ISO 400 film, you'd move down two numbers, i.e., pass 320 and set your meter to 250. Does that make sense?

Once you've done that, just meter and place the shadow in your desired Zone and err on the side of overexposure if you can't apply the exact setting. The difference between 1/3-stop and 1/2-stop is only 1/6-stop - Nothing to worry about with b&w negative film (which I assume we are discussing here).

As for developing: There's really no such thing as "developing for 2/3-stop slower than box speed." I know that a lot of amateurs talk about "developing a stop slower or faster" or whatever, but things really don't work that way.

The amount of developing determines the contrast gradient on the negative, that is, the amount of density difference per extra stop of exposure. So, what you are after really is a development time that allows you to print the highlights from a scene with a "normal" subject brightness range (SBR) at a "normal" contrast setting on VC paper (that would be with a #2-#3 filter).

The manufacturer has tested developers with their film and arrived at a good starting point. You should use that first and then only deviate once you feel the need. If you're using a film/developer combination that neither the film or developer recommendations list, then check the Massive Development Chart online or inquire here for starting points. Note that the way you develop makes a difference in the time (tray, tank, rotary, etc.)

Then, to test your system make a few proper proofs. That's a print made at a middle contrast setting and exposed at the minimum time it takes for the black from a clear area of the negative like the rebate around the image to be rendered really, really close to maximum black on the paper. The way to do this is to make a test strip of the negative, leaving a bit of empty space at the edge of the negative for light to strike the paper without passing through the negative. You can then compare the black of the rebate and the black of the area exposed without the light passing through the negative. Evaluate the test strip when dry and in "normal" lighting for exhibiting prints. When in doubt, err on the side of the shorter exposure.

Once you have your proper proof exposure, proof a few negatives and see what they look like. If everything is overall way too dark, you've likely chosen the wrong proofing time. However, if your shadows look close to where you want them, you're on the right track. Now examine the highlights: If they are consistently too dark for "normal" scenes, your film developing time is too short, and vice-versa.

Similarly, if you are getting good blacks in really clear areas of your negative, but the shadows are still to dark, then you should rate your film slower and vice-versa.

Keep refining as you go. Remember, you've got lots of leeway with VC paper to deal with scenes with more or less SBR. The trick is to find the sweet spot for developing time that allows you to print the extremes of the things you photograph. If you consistently find that you're using the #5 filter or the #00 filter a lot, then adjust your developing time so that things are closer to whatever is the middle for you.

If you use sheet film, you can try exploring longer and shorter development times for scenes with lower and higher SBRs, respectively. Add 20% to your "normal" developing time for a starting point for N+1; subtract 20% for N-1. Repeat the proper proof tests for these times to refine.

Hope this helps,

Doremus

Thank you Doremus

Simlpy put and perfectly understandable

All of the assumptions that you made in the beginning of your reply where 100% accurate.
Good notes and consistent technique to produce repeatable results.

 

[JerseyDoug]

I've never owned a step wedge, nor have I even seen one. So that leaves me out.

For me the best test, I reckon, is the simplest one ever devised (by me, tho' I would never claim to be its original creator, surely others have done this, long before I came along and bought my first Yashica TLR. Some guy named Ansel, I think, thought it up on or about 1940, tinkered with it a bit, expanded it, and made his reputation out of it, along with LF snapshots of Yosemite. Obviously, it must work.).

First, you find a brick wall. Then you wait for an overcast but bright day.

Put your camera (loaded with film, of course) on a tripod and expose as follows -

Normal exposure - then reverse, three steps (-0.3, -0.7, -1.0), then forward, three steps (+0.3, +0.7, +1.0).

Process the film as you always do. Normally. Evaluate the results.

Next, repeat the process on a sunny day. As per above.

By which time you may have figured out that something seems to be wrong with your processing workflow. Especially if you use replenished developer, or you home-brew using chemistry not intended for film developers (supermarket laundry borax instead of sodium metaborate, etc etc). So you test your developer by reshooting the lot, dividing the rolls into three equal parts, and developing for 0.5 (half) the time, 1.0 (normal) time, and 1.5 (normal and half again).

Eventually you go insane from it all - and the entire problem goes away by itself.

Been there, done that.

For 35mm, my current process for determining a working film speed is to put a 36-exposure roll of the film in my Nikon F6, set the F6 ISO to box speed, shoot a variety of subjects in a variety of lighting conditions, develop the film for the film and developer manufacturer's recommended time (or the average of the two times if they differ), and make prints of the most problematic looking frames. This has always resulted in usable, if not ideal, negatives.

I then shoot two or three more rolls of the same film, iteratively adjusting the F6 ISO and/or the developing time up or down after evaluating the previous set of prints for shadow detail and highlight treatment. After a total of four rolls (and sometimes only three rolls) I can no longer decide whether the ISO or the developing time should be increased, decreased, or left alone, and I'm done.

Coincidentally, I am doing this right now now with FP4 Plus developed with FX-39. I have one last roll to develop and print but it is looking like I will settle on ISO 100 developed for 11.5 minutes at 68ºF. I had enough confidence that I was at or very near the right numbers (for me) that I used the roll for some money shots.

Once I determine my working speed for a film I can put the monster F6 back on the shelf and return to using my LTM Leicas with incident metering. (Translating the F6 all singing all dancing reflective metering to incident metering is a subject for another conversation.)

 

[Bill Burk]

I did the testing procedure described by Bill in post #3 and I ended up with HP5's speed being 500.

Wait. If you get 500 by sensitometry tests and have met the ASA criterion, then you should change the number to 400 and recalibrate to 400.

Unless you had already performed the tests developed in D-76 and got 400 in that combination, then switched to XTOL and saw a 1/3 stop increase in speed…

Then you could say that you got 500.

But in general that film in a standard developer should give 400

 

[Down Under]

Been there, done that.

For 35mm, my current process for determining a working film speed is to put a 36-exposure roll of the film in my Nikon F6, set the F6 ISO to box speed, shoot a variety of subjects in a variety of lighting conditions, develop the film for the film and developer manufacturer's recommended time (or the average of the two times if they differ), and make prints of the most problematic looking frames. This has always resulted in usable, if not ideal, negatives.

I then shoot two or three more rolls of the same film, iteratively adjusting the F6 ISO and/or the developing time up or down after evaluating the previous set of prints for shadow detail and highlight treatment. After a total of four rolls (and sometimes only three rolls) I can no longer decide whether the ISO or the developing time should be increased, decreased, or left alone, and I'm done.

Coincidentally, I am doing this right now now with FP4 Plus developed with FX-39. I have one last roll to develop and print but it is looking like I will settle on ISO 100 developed for 11.5 minutes at 68ºF. I had enough confidence that I was at or very near the right numbers (for me) that I used the roll for some money shots.

Once I determine my working speed for a film I can put the monster F6 back on the shelf and return to using my LTM Leicas with incident metering. (Translating the F6 all singing all dancing reflective metering to incident metering is a subject for another conversation.)

Gosh, what a minefield we've laid down with this thread...

Anyway, about your post, Doug. In general, your system will work well too, I reckon.

Except for the part about shelving the F6 and using other cameras. Leicas or not, the problem starts all over again, as no two cameras will ever have exactly the same shutter speeds. With any luck at all, they will all be fairly close together, but there isn't any guarantee, especially with older cameras.

Also, nowadays I don't make prints of everything I shoot. Not enough time, I'm now too old. Over the decades I've learned to eyeball my negatives, and if I need to check the finer points of an image, I scan the thing. Much easier to fine-tune half a dozen adjustments to the scanner than to print six prints. A lot kinder on resources too, not to overlook cheaper on my pensioner's budget.

Otherwise, it would seem that all's fine and good with your sytem.

The ideal method, of course, would be one devised so that we can get down to the basics of which exposure/film EI is best, using one roll of film for testing only. Given the price of film these days.

Now to add yet more fuel to this fire - in the days when I used 120 almost exclusively in my Yashica D and then my Rolleiflex, I didn't have any of the problems associated with EI speeds. Everything just seemed to come out fine, but that was in the 1960s and 1970s, two different world entirely. Then I moved to 35mm and all my problems really started.

I've never quite worked out why this is or what to do about it, other than as time passed, films changed, and this had everything to do with it. Less silver in the mix, maybe.

 

[Craig]

Wait. If you get 500 by sensitometry tests and have met the ASA criterion, then you should change the number to 400 and recalibrate to 400.

Unless you had already performed the tests developed in D-76 and got 400 in that combination, then switched to XTOL and saw a 1/3 stop increase in speed…

Then you could say that you got 500.

But in general that film in a standard developer should give 400

I only used Xtol as my developer. I used Phil Davis's method from BTZS and a friend has the software to analyze the results. I gave him a spreadsheet of all my densitometer results from the 5 sheets of each film. I contact printed the step wedge under my enlarger, then developed in my jobo for 4, 5.5, 8, 11 and 16 min. I did this for both HP5 and Delta 100.

I mainly worked backwards from the contrast index to determine a developing time, and from that an effective film speed. I also bought the ExpoDev app from my phone, and that gives an effective film speed and developing time for each scene that I meter.

For Delta 100, my speed was around 80 and I have always had great negatives with a 7-1/2 min developing time.

My HP5 negs however, have always been thin and flat with the 8 min ( from Ilford) or worse with the 7-3/4 (Kodak) recommended times. After doing this analysis I have gone to a 9'20" developing time for an average scene and my negs are coming out much better. As a consequence, the film speed from charts suggests 500. I use whatever the app says for the particular scene I'm photographing and I'm getting much better results than I used to. Using the 8 min time, my testing came to a contrast index of 0.50, which would explain why my negs were lacking contrast. By extending the development time they are looking much better.

The charts below are the output from the software showing all the parameters. Ignore the 70°F in the header, it was really processed at 20°C in replenished Xtol. HP5 charts first, Delta 100 second.

 

[Bill Burk]

@Craig I know how it feels to have a developer you don’t stray from. I won’t ask you to buy a bag and mix it up because I know I wouldn’t like to get a bag of XTOL and mix it up. It’s just too much trouble.

I always use D-76 1:1 and calibrate sensitometer exposures and graphs to 0.1 density above filmbase plus fog where TMY2 met ASA parameters. I call that 400 and calibrate my sensitometer there (edit the graph in InDesign and slide the exposure scale to align -2.7 with the 0.1 density of that film that met ASA - typically 13 minutes 30 seconds in D-76 1:1 at 20-degrees C).

I had a couple rolls of HP5 plus that I got for testing but already shot them up. I might have included a sensitometry strip to read… If so I’ll check and see if I got 400 in D-76 1:1

Something is squirrely here in your speeds. Somewhere along the way you should have a film that meets its speed criteria at ASA parameters.

Don’t use the sliding speed of BTZS - it’s based on a fallacy and will say your 100 speed film is 80 at 0.5 contrast. Speed doesn’t slide that way. Maybe that’s the issue.

If you want to share the densities I could graph them out on paper to see what you have. (Maybe attach a spreadsheet or text file).

Bottom line: 400 should be 400 at ASA parameters. If it isn’t, a couple big reasons could be you found a developer that increases speed (and that should be easy to confirm if true), or the calibration of your test exposure needs a tweak.

I find slight variations in different films. For example I find Panatomic-X to rate 50, but I don’t tweak the sensitometer calibration to my finding because I figure it has unique spectral sensitivity.

But fresh TMAX100 and TMY2 lock in at 100 and 400 for me.

 

[Sirius Glass]

I use replenished XTOL in a Jobo processor for 35mm, 120 and 4"x5".

 

[gone]

I guess my method for finding out the film speed is not really about that, but it enables me to see what's up. With a new film, I'll shoot the whole roll making 3 frames of each subject. 1 pic will be shot at half box speed, the next at box speed, and the next at twice box speed. Then develop it normally. This will give me a good idea of which way I might want to go.

There's many other things one needs to be aware of. What kind of light do you expect to encounter the day you shoot, which kind of enlarger is being used, RC or FB paper, which film developer and at which dilution, what the subject matter will be, etc.

 

[JerseyDoug]

...Anyway, about your post, Doug. In general, your system will work well too, I reckon.

Except for the part about shelving the F6 and using other cameras. Leicas or not, the problem starts all over again, as no two cameras will ever have exactly the same shutter speeds. With any luck at all, they will all be fairly close together, but there isn't any guarantee, especially with older cameras....

The reason I use the F6 is that it has an electronically controlled shutter with a built-in monitor. Nikon's claim is that the shutter speed accuracy is as good as that of the factory's test equipment.

In real life, focal plane shutters with inaccurate shutters are invariable too slow. Not once have I ever picked up an unfamiliar camera, tried the shutter at 1 second and thought, "that sounds too fast." Slow shutter speeds cause overexposure which is much more tolerable than underexposure with film. None of my shutters (all tested) are far enough off speed to require compensation.

 

[Craig]

If you want to share the densities I could graph them out on paper to see what you have. (Maybe attach a spreadsheet or text file).

I sent the data as a PM, since I couldn't attach a spreadsheet to the forum reply.

 

[Sirius Glass]

The reason I use the F6 is that it has an electronically controlled shutter with a built-in monitor. Nikon's claim is that the shutter speed accuracy is as good as that of the factory's test equipment.

In real life, focal plane shutters with inaccurate shutters are invariable too slow. Not once have I ever picked up an unfamiliar camera, tried the shutter at 1 second and thought, "that sounds too fast." Slow shutter speeds cause overexposure which is much more tolerable than underexposure with film. None of my shutters (all tested) are far enough off speed to require compensation.

The prime reason that you use the Nikon F6 is that you own it. Right!?!

 

[Bill Burk]

The prime reason that you use the Nikon F6 is that you own it. Right!?!

I knew the F6 was good but didn’t know it was “self-aware”

 

[Bill Burk]

I sent the data as a PM, since I couldn't attach a spreadsheet to the forum reply.

Thanks!

I thought I had properly calibrated my SEI photometer until I went to confirm EV 6 and EV 12 on a variable test light. The Sekonic L758-DR disagrees by 2/3 stop.

Just illustrates that sometimes properties of a device you want to use as a standard are off by a bit.

 

[Bill Burk]

I always use the Zone system and a hand held meter, none of my cameras have 1/3 stops only 1/2 stops

My conclusion from all this information?

Set my hand held meter to 2/3's box speed, place the shadows in my desired Zone, set my camera to the metered settings, if the settings can't be set to the metered settings overexpose to the next closest setting.

Each film speed setting is 1/3 stop and we say give two more of these third stops. So from 400 speed a third stop more exposure is 320 and two-thirds more than 400 is 250. Use 250 as a general rule of thumb.
And it’s for mechanical reasons because ASA sets shadows 3 1/3 stop down from gray but Zone System set it up as 4 stops down from gray.
Yes you pick the nearest setting.

 

[Bill Burk]

And I suppose you should think the 2/3 stop exposure increase for Zone System is only relevant if you are reading and evaluating exposure based on shadow values. Around Zone III, 400 is 250.

If values that you are reading and placing are Zone V and above, the difference is gone. Zone V and up, 400 is 400.

When people talk about how they love extra shadow detail when they give 2/3 stop extra exposure. That’s a different reason! Now if that’s the reason, more power to you. Keep 400 at 250 because you like the look

 

[JerseyDoug]

The prime reason that you use the Nikon F6 is that you own it. Right!?!

I did own it at one point. Now I borrow it from my wife, and only for this purpose. When I want to use an automatic everything camera I much prefer my N75 with a 50/1.8D lens. Less than half the weight and less than 1/50 the cost to replace it if I do something stupid.

 

[Sirius Glass]

I did own it at one point. Now I borrow it from my wife, and only for this purpose. When I want to use an automatic everything camera I much prefer my N75 with a 50/1.8D lens. Less than half the weight and less than 1/50 the cost to replace it if I do something stupid.

I too have an N75 which I just used yesterday with Portra 400 film.

 

[Stephen Ryde]

And I suppose you should think the 2/3 stop exposure increase for Zone System is only relevant if you are reading and evaluating exposure based on shadow values. Around Zone III, 400 is 250.

If values that you are reading and placing are Zone V and above, the difference is gone. Zone V and up, 400 is 400.

When people talk about how they love extra shadow detail when they give 2/3 stop extra exposure. That’s a different reason! Now if that’s the reason, more power to you. Keep 400 at 250 because you like the look

And I suppose you should think the 2/3 stop exposure increase for Zone System is only relevant if you are reading and evaluating exposure based on shadow values. Around Zone III, 400 is 250.

If values that you are reading and placing are Zone V and above, the difference is gone. Zone V and up, 400 is 400.

When people talk about how they love extra shadow detail when they give 2/3 stop extra exposure. That’s a different reason! Now if that’s the reason, more power to you. Keep 400 at 250 because you like the look

Thanks Bill
Yes I am evaluating all this according to the shadows