The Ultimate Exposure Computer

[Michael Guzzi]

[...]What's your speed range?

B to 1/500, plus T and (I believe) M and X flash synch. I say "I believe" because it's not here yet! I have some fresh RPX400 waiting for it! I have a spare Tempor with a SH Culminar on it, just in case. The Tempor looks and feels way cheaper than a Compur, but gets the job done too. Besides, with the limited maximum aperture on these folder lenses 1/500 is a bit OTT IMO, and that 1/500 is more like 1/400 most times too.

 

[Monday317]

I think you're thinking of Monolith, not Moonrise. Moonrise was indeed made without a meter (and underexposed about a stop) but he used a yellow filter, and Moonrise was not in the darkroom fire.

You thinketh wrong, mon ami: Moonrise was singed in the fire and requires a teeny bit of cropping and burning on an upper edge to Get It Right. That said you are correct about the filter: it indeed was a Wratten #15 (G) Deep Yellow, not a #25 Deep Red as I misidentified it:

"I was at a loss with the subject luminance values, and I confess I was thinking about bracketing several exposures, when I suddenly realized that I knew the luminance of the moon – 250 c/ft2. Using the Exposure Formula, I placed this luminance on Zone VII; 60 c/ft2 therefore fell on Zone V, and the exposure with the filter factor o 3x was about 1 second at f/32 with ASA 64 film. I had no idea what the value of the foreground was, but I hoped it barely fell within the exposure scale. Not wanting to take chances, I indicated a water-bath development for the negative."--quote from Examples

 

[Monday317]

B to 1/500, plus T and (I believe) M and X flash synch. I say "I believe" because it's not here yet! I have some fresh RPX400 waiting for it! I have a spare Tempor with a SH Culminar on it, just in case. The Tempor looks and feels way cheaper than a Compuir, but gets the job done too. Besides, with the limited maximum aperture on these folder lenses 1/500 is a bit OTT IMO, and that 1/500 is more like 1/400 most times too.

Yup, got mine from Certo6, who said the same thing. 1/250 may be attainable, but not reliable. Your Compur sounds great, especially with the fine old Tessars!

 

[MattKing]

BTW, if ic-racer is me, then who am I.

His long lost cousin?

 

[ic-racer]

Yes Cousins! In fact, I tried to catch up with Steve to share the news with him and it went something like this (my real name is Alfred):

 

[NedL]

Hi! Late to the party here, but I love my Ercona II. I use it mostly outdoors, and rarely carry a lightmeter with me these days. I don't use exactly the ultimate exposure computer version of sunny-16... my version pays more attention to the nature of shadows ( e.g. shadows w/ crisp edges, blurry edges, just dark blobs under trees, not visible at all .... ) I can't remember now where I learned that but it works well except in deep forest/shadow where I pay more attention to how much open sky is above....

Still, for anything critical I tend to carry some kind of light meter, sometimes it might just be another camera with a meter that I'm well familiar with.

By the way, do you guys use the "red dot" snapshot setting? I've found it only useful for snapshots when the subject is ~3 or 4 meters away and you don't care if the horizon is sharp.... it's definitely NOT "hyperfocal" in the usual sense. cheers!

 

[Monday317]

In the interest of accuracy, let's set this straight.
On p.5 of Examples is clearly described the fire damage to the Monolith negative, made in 1937.
On p.43 of Examples Moonrise was best dated as 1941, using the Wratten #15 (G) Deep Yellow filter.

Curiously, though, he shows in the Negative that the factor for #15 is 2.5 (daylight) and 2.0 (tungsten or warm light), not a factor of 3. And for a setting sun it seems the 2x factor would apply, so the 3x would have helped a bit with the low foreground luminance but obviously not enough. Here's what my exposure calculation comes up with, using the data he provided:

Exposure Formula requires the key stop to be f/8 (sq. root of ASA 64) at Zone V
1/250 @ Zone VII
1/60 @ f/8 = Zone V
1/4 @ f/32 (w/o 3x filter factor)
3/4 @ f/32 (w/ 3x filter factor)
3/4 should not require reciprocity correction
OK, he did say about 1 sec. (Not sure when he decided to be a stickler for record keeping). And it’s possible he applied a personal EI.
BTW, in the Negative he quotes Kodak's recommendation for reciprocity correction at 1 sec to be an additional 1 sec, so he was on the brink.

I hereby play The Age Card and chastise you for messing with an old geezer's mind, when his copy of Examples in storage at Fairbanks, AK.

Yes sir, you are correct on all counts as my trip to the library confirmed, and I apologize to one and all on insisting incorrect information was the goods. D'OH!!

FWIW, the Adams site mentions that another astronomer found tyhe moon's position incorrect as stated for the time originally calculated. October 31, 1941 @ 1605L (IIRC!). The coorected date & time is November 1, 1941 at 16:20:22L; how they got that down to the second, I can only guess. The new time was confirmed by the previous astronomer, so short of a trip in a time machine, we can accept this as the Real Deal.

Thank you, SilverorO for keeping me--and the rest of us--on the straight and narrow, in a polite, reasonable manner; much to be admired. Mmmm...crow. Great with Frank's Red Hot!

 

[Monday317]

Hi! Late to the party here, but I love my Ercona II. I use it mostly outdoors, and rarely carry a lightmeter with me these days. I don't use exactly the ultimate exposure computer version of sunny-16... my version pays more attention to the nature of shadows ( e.g. shadows w/ crisp edges, blurry edges, just dark blobs under trees, not visible at all .... ) I can't remember now where I learned that but it works well except in deep forest/shadow where I pay more attention to how much open sky is above....

Still, for anything critical I tend to carry some kind of light meter, sometimes it might just be another camera with a meter that I'm well familiar with.

By the way, do you guys use the "red dot" snapshot setting? I've found it only useful for snapshots when the subject is ~3 or 4 meters away and you don't care if the horizon is sharp.... it's definitely NOT "hyperfocal" in the usual sense. cheers!

We probably oughta start an Ercona Owner's Thread. If you are getting good results with your camera, I doubt we would care if you used a crystal ball, or consulted squirrels--so long as it works! Don't you love those huge 6 x 9 negs?

I haven't used the red dot at all. Given what it takes to get a decent shot, I would agree this is no point-and-shoot camera. If you know enough to use one, the red dot is moot, these day, at least. I have found my camera doesn't do well even out to 1/100 hand held, so am finishing refurbing an old tripod I got on eBay last year. With a cable release, I think those blurry details should go away! I have the manual for the camera and lens and have been working on a spreadsheet for a DOF calculator, FWIW. But range focusing so far works fine 90% of the time. But trying to use a Portra +1 lens is another matter...

Enjoy!

 

[removed account4]

Yup, got mine from Certo6

good luck with that ....

 

[Monday317]

good luck with that ....

Not the first time I've heard that. I personally have zero problems with Jurgen, but he can be prickly if he feels someone is being unreasonable, or demanding. How that shakes out on an individual basis, I couldn't say. His work has been fine with any task I asked and paid for.

 

[NedL]

The 6x9 negatives are wonderful to print. I have a print that if you pull out a magnifying glass you can see the wire on a fence that must have been 3/4 mile away. I actually like the "red dot" setting ( for the aperture, not focus! ) because it's my "sunny 16" setting for acros at 1/100... and it reminds me to knock off about 1/3 stop from "normal" when using that film. I use it handheld and on tripod about 50/50, but agree you need to be careful handheld even at 1/100. FWIW, I got mine from Jurgen too, and I love the camera. So far I've never tried the 6x6, but I've got the insert for it.

 

[Bill Burk]

On p.43 of Examples Moonrise was best dated as 1941, using the Wratten #15 (G) Deep Yellow filter.

Curiously, though, he shows in the Negative that the factor for #15 is 2.5 (daylight) and 2.0 (tungsten or warm light), not a factor of 3. And for a setting sun...

silveror0,

Your thoughts here sent me down a rabbit hole...

Does anyone know the film used for "Moonrise, Hernandez, New Mexico"?

I have a guess, based on what he used in "Making a Photograph" 1935 (where it says... "Unless otherwise noted all..."), and in "Yosemite Valley" 1959 (where he gives exposure information based on "ASA 64" black and white film). I'm thinking he stuck with one film as long as he could. (Keep in mind that we are talking about a film you might rate at ASA/ISO 125 today, but it was rated at 64 under the old system... and I'm having trouble confirming numbers for this particular film so I don't really know if it really was 64).

In 1941 my guess is he may have been shooting Eastman Super Sensitive Panchromatic Film. This film, I am guessing might be what would be classified as an extended-red "Type C" panchromatic emulsion. So, silveror0, you would be right... the factor for a "Type C" film with #15 is 2.5 (daylight) and 2.0 (tungsten). But the light was fading fast, and I think you might agree that most of the light in the scene was cool daylight...

But for the light on the crosses, I just realized... they would be lit up by warm light... and so where the crosses are concerned, the 2.0 tungsten factor would be right. (In other words, that warm light got through the filter and kept the exposure on the crosses high).

Luck really was running in Ansel Adams' favor.

 

[removed account4]

Not the first time I've heard that. I personally have zero problems with Jurgen, but he can be prickly if he feels someone is being unreasonable, or demanding. How that shakes out on an individual basis, I couldn't say. His work has been fine with any task I asked and paid for.

you are very lucky.
he mistreated my camera so extremely bad, i will never have anything to do with him again.
i won't pollute your thread with the details but you are very lucky.

 

[pbromaghin]

Thank you for posting TUEC. I printed that out and used it to shoot without a meter for a couple of years with my Zeiss. It taught me an awful lot about photography.

 

[Bill Burk]

So, Bill, you're finding it difficult to do meaningful research down in the darkness of the rabbit hole?
BTW, note my edit in post #33 regarding use of a personal EI.

It's fun. I'm like a rabbit in the briar patch... of course it would be Ansel Adams' personal speed. But in 1941 his speed would be close to ASA speed of the time.

Ran across a reference that told me Weston speeds began with an arbitrary number 12 for a common film for which... for a brightness of 100 candles per square foot... the meter would indicate an exposure of f/4 and 1/100 second. This isn't quite "Sunny 16" yet. And it's not the "exposure formula" either.

 

[Bill Burk]

Does anyone know the film used for "Moonrise, Hernandez, New Mexico"?

I have a guess...he may have been shooting Eastman Super Sensitive Panchromatic Film.

A friend has suggested that an early reference quoted Ansel Adams saying it was Panatomic-X.

It's easier to arrive at a one second exposure with the given factors if you consider the film might be Panatomic-X

But it's also reasonable to think that Ansel Adams might not have been really thinking "Zone VII Moon" when he made a one second exposure for Eastman Super Sensitive Panchromatic Film. He may have been thinking "it's near the upper limit, I better be careful when I develop"... which he says he marked for water bath development.

I found Weston speeds for Eastman Super Sensitive Panchromatic Film in 1941 50 (tentative) which would have been ASA 64

And a Weston speed for Panatomic-X in 1941 24 would have been ASA 32

Now it's also interesting to note that John L. Davenport published "Constant Quality Prints" in 1940. Which Ansel Adams used as inspiration for the Zone System. This suggests to me that either the Zone System was rapidly developed in 1940-1941... Or perhaps Ansel Adams didn't really "Place the Moon on Zone VII"


I think the computation comes out like this...

If the film is Panatomic-X, he placed the moon on Zone VII.

If the film is Eastman Super Sensitive Panchromatic Film, he placed the moon on Zone VIII.

 

[pbromaghin]

You thinketh wrong, mon ami: Moonrise was singed in the fire and requires a teeny bit of cropping and burning on an upper edge to Get It Right. That said you are correct about the filter: it indeed was a Wratten #15 (G) Deep Yellow, not a #25 Deep Red as I misidentified it:

"I was at a loss with the subject luminance values, and I confess I was thinking about bracketing several exposures, when I suddenly realized that I knew the luminance of the moon – 250 c/ft2. Using the Exposure Formula, I placed this luminance on Zone VII; 60 c/ft2 therefore fell on Zone V, and the exposure with the filter factor o 3x was about 1 second at f/32 with ASA 64 film. I had no idea what the value of the foreground was, but I hoped it barely fell within the exposure scale. Not wanting to take chances, I indicated a water-bath development for the negative."--quote from Examples

Funny, but a former (early 80's) assistant to Ansel, David Pfau, told me this was a BS story they made up after the fact to add some drama. He tells it that Ansel was napping while his assistant drove. The assistant saw the potential photo, stopped the car and set everything up. Then he woke Ansel up to go trip the shutter, thereby making it a real Ansel Adams original. No panic, no missing light meter. I never did get the assistant's name. If you're ever skiing in Breckenridge, CO, stop in his shop on Main Street. But who knows, he might be full of crap, too.

 

[removed account4]

Funny, but a former (early 80's) assistant to Ansel, David Pfau, told me this was a BS story they made up after the fact to add some drama. He tells it that Ansel was napping while his assistant drove. The assistant saw the potential photo, stopped the car and set everything up. Then he woke Ansel up to go trip the shutter, thereby making it a real Ansel Adams original. No panic, no missing light meter. I never did get the assistant's name. If you're ever skiing in Breckenridge, CO, stop in his shop on Main Street. But who knows, he might be full of crap, too.

i had a college roomate who worked as an assistant on a variety of trips with an extremely well known
photographer back in the day ( 80s/90s ) she directed the exposures. everyone scurried around did "stuff"
he set everything up, she just tripped the shutter. i worked for pros as well, set everything up they pushed the button ...
and when i worked in an environmental firm plenty of times i wrote reports that others put their name on ...

the story is plausible, .. assistants .. assist, and more often than not, someone else gets the credit.

 

[removed account4]

Plausible, yes, but not certifiable.

even if AA was around it would be a he said she said and because AA has a reputation people would claim the assistant was FOS.
plenty of assistents do most if not all the work while the "name" gets the glory.

 

[pbromaghin]

Spreading rumors of this sort is analogous to challenging the integrity of someone who's no longer with us and cannot defend against this crap, in effect calling AA a liar after (1) witnessing him in a live public presentation describing his challenges at the time of his taking the photo, and (2) allowing his biographer to publish the story as he knew it. BTW, who are the individuals who concocted this story, identified as they? Yes, I'd say for sure "he's full of crap." And also, btw, I've not found anywhere on Mr. Pfau's website where he states he was an assistant to AA, after merely attending a Yosemite workshop in 1983. So please knock off this stuff.

Mr Pfau told this story to Laostyle17 and me 3 years ago when we were the only customers in his shop on a slow off-season day. According to Mr Pfau, the story was the source of a lot of laughs on the occasion. I'm sorry that I am not familiar with who might be hanging out at Ansel's house for cocktails on this particular occasion, but it was at least Ansel and his son, and probably the Turnages. Ansel a liar? Not hardly. How about a mischievous imp in the 1940's, blowing smoke up a few chardonnay-swilling, oh-so-artistically-correct butts at a gallery opening, little realizing the story would become world famous and he'd be stuck keeping it up for 40 years?

Why Mr Pfau wouldn't mention a college summer job in a one-paragraph summary of a 40 year career, I couldn't say. It ain't my story. You have his phone number. Call him up and tell him he didn't hear what he heard, see what he saw, or do what he did. That ought to go over real well. I'd love to hear that conversation. But as the saying goes, he might have been blowing smoke up MY butt.

 

[CMoore]

Regards The Computer...I recently wondered what experience you guys may have had using it, on a "typical" down-town street at night, with Ilford FP4.
I suppose the best thing is to just give it a shot myself.....follow The Computer and see how the negatives develop.

 

[Bill Burk]

I just picked up an extinction meter - my first - an Addiphot. What is remarkable to me is that this device looks an awful lot like Fred Parker's Ultimate Exposure Computer.

Here is my take on how you use it. First you pick the main number for sun, clouds, bright indoors, dark indoors... then add the number you can see on the extinction scale. Since your eyes are always adapted to conditions, the highest visible number will usually be around 2 or 3.

The scale slides over the holes but I don't think it's part of how you use it. I think you show all 7 holes, read it, and then use the slide rule.

I'm not having the best luck with guessing exposures using it.

This seemed to have an amazingly long lifetime in the market... It seems to have been made in the thirties, and I see Popular Mechanics magazines from the '60s and '70s still advertising it.