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From Wikipedia, the free encyclopedia

Equivalent (1926), one of many photographs of the sky taken by Stieglitz.

Equivalents is a series of photographs of clouds taken by Alfred Stieglitz from 1925 to 1934. They are generally recognized as the first photographs intended to free the subject matter from literal interpretation, and, as such, are some of the first completely abstract photographic works of art.[1]

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Transcription

I went to Wikipedia, and I decided to pick up the definition for an equivalent there. And I actually didn't find it too useful, but there are some things that I wanted to point out. So it says, "The equivalent is formally defined as the amount of a substance which will either react or supply with one mole of hydrogen ions in an acid base reaction; or do the same with one mole of electrons in a redox reaction." So all I've really figured out so far-- I was a little confused when I read this-- but I figured out what they are saying is that an equivalent is basically some amount, some number, right? So let's start there. So when someone says, hey, how many equivalents do you have? I know that they're talking about some number. So equivalent is equal to-- and this is for some ion, right? So for some ion of my choosing an equivalent equals some number. And usually that number is in terms of moles. So some number of moles that I need, so needed to balance something. I'm actually balancing some charge. So balance the charge of an oppositely charged-- so an opposite charge-- opposite monovalent. Actually, I should even add, balance the charge of-- I guess I can add without erasing-- charge of one mole-- that's actually really important-- of an oppositely charged monovalent. OK, so let's jump into an example, because I think that will clear up any confusion that you may have to this point. So let's say we're talking about, for some ion, let's say we pick potassium, OK? Here's our potassium. And I've got to balance out one mole of an oppositely charged monovalent. So this is my little line demarcating the other side. So on the other side let's say we have chloride. And chloride is oppositely charged. It's negative, right? And it's a monovalent. It's not negative 2, or negative 3. It's just negative 1, right? So we've got, let's say a mole of these, because the definition I wrote up just said that I needed a mole of an oppositely charged-- and as I'm writing this up, I'm realizing, and I hope you are, too, that there's no way in the world I can write up a mole of this stuff. There's no way, right? So let me just get the point across that, just imagine that there are a total of this many-- 6.02 times 10 to the 23rd chlorides. Because that's really the question. How many potassiums do you need to balance out the charge from all of those chlorides. And that's too big a number, too big a number to write out in any easy way, other than to say, well, maybe you need some number of moles of potassium. And that's why I wrote that right into the definition. So let's figure this out. So we know that potassium binds one to one with chloride, right? We know that's what happens. So when potassium's floating around, and it's gonna bump into chloride, it's going to go one to one. So we know that for one chloride, we're going to get one potassium. And so that means that for one mole of chlorides, we're going to get one mole of potassiums bound to them, right? And that's going to balance out the charge perfectly. So if someone says, well, how many equivalents do you have for potassium? That seems like a very simple answer. Well you say, OK, well, one equivalent would then be one mole of potassium. Or you could even rephrase it. You could say, well, in one mole of potassium-- and this is how people usually use the phrase. They say, well, 1 mole of potassium equals 1 equivalent. So I know that's the same thing flipped around, but that's how people usually state it. So now let's do a slightly more challenging example, and you'll see where this becomes a little different. So instead of potassium, let me jump into another one. Let's do calcium. Calcium-- so there's a plus 2. And same thing as before. I'm going to have to choose some oppositely charged monovalent. And I'm going to pick the same one, because this still is oppositely charged. I just needed some negatively charged monovalent, and chloride suits our purposes. And we know, just as before, we need a whole mole of them. And so if that's the case, how many calciums will bind to a chloride, and vice versa. How many chlorides will bind to a calcium? So let's imagine we have a little chloride and calcium party, and they can meet each other. Well, what's going to happen is, that you're going to have a calcium there, and a chloride there, and a chloride there, right? Because this will come here. This will come here. And they're going to basically bind and make this. They're going to make CaCl2, because the chlorides are only one negative charge-- actually, and this is two positive charges. I'm flipping around my negatives and positives. Sorry about that. There we go. Negative, negative, and plus 2. So you know that for every one calcium, you're going to get two chlorides. So let me write that out very clearly. So for every one calcium-- or actually I can write for every two chlorides you get one calcium, right? And that means that for every-- if I divide both sides by 2-- for every 1 chloride, I basically needed a 1/2 a calcium. And that's not how we think about it, usually, because it's hard to imagine 1/2 a calcium. But at least the math works out there. And so if I'm talking about one mole of chloride, then I'm left saying, well, then I have a 1/2 a mole of calcium. So far so good. And so, then, 1 equivalent, going back to our definition, equals 1/2 mole of calcium. And I said that we could flip around the equation, and we can. We could say, well, then 1 mole-- now all I did is multiplied both sides by 2-- 1 mole of calcium-- I'm not writing clearly right now, sorry-- 1 mole of calcium equals 2 equivalents. So there is how people usually phrase it. They'll say, OK, well, how many equivalents do you get for 1 mole of something? And so here you would say the answer is 2. And so I just want to point out something to you, which is that we kind of did this a long way, but here is a quick and dirty way. You could say, well, I know that calcium is divalent, and we know that potassium is monovalent, and here is kind of an interesting pattern that's emerging, right? As this Ca plus 2 emerged, we got 2 equivalents out of it. Let's test this with a third one. Let's just see what we get if we use, let's say, nitrogen. So let's do nitrogen. Nitrogen is negative 3. And I have to create my boundary, and on the other side, I need some oppositely charged monovalent. So there's a monovalent and it's opposite-- here's monovalent, check, and it's oppositely charged, check. Opposite. Opposite of the negative, right? So check, check. It meets our requirements. And I need a mole of them. So I have to draw out a mole, and you know there's no way I can do that, as I said before. And so just imagine 1 mole of these guys. And the question, again, is how much nitrogen do I need to balance all this out? And I'm gonna just underline in red the clue. So here's the clue. And let's now actually go through the steps of figuring it out kind of the longer way. So let's imagine you have a nitrogen here, negative 3, and it's going to be at this, let's say, cocktail party, and it meets some protons. And in this case, 3 of them come by. So it's going to form NH3, right? If we say 3 protons then come together with 1 nitrogen, which is what we just said, then I can divide both sides by 3, and I can see that 1 proton then comes with 1/3 of a nitrogen. So far so good. And I can then even go on to say 1 mole of protons, which is going back to our definition, would be balanced out by 1/3 of a mole of nitrogen. And if that's the case, then I can say, well, 1 equivalent equals 1/3 third of a mole of nitrogen. And I'm going to flip this around, just as we did before. I could say, then 1-- let me change that-- I could say, then 1 mole of nitrogen equals 3 equivalents. And remember, we underlined that little 3 in the beginning, and I'm going to underline it again. And now you can very clearly see the pattern that's emerging. So you can see that any time you look at the cation or anion that you're talking about, if you look at the number-- like if it's, let's say, magnesium, that's 2 plus, or calcium is 2 plus-- then you can know immediately that that probably means, if you did the work the long way like we just did, that the equivalents are going to work out to the same number. So nitrogen has 3 equivalents. Magnesium or calcium have 2 equivalents. And potassium and chloride, they all have 1 equivalent. So that's what equivalents mean in terms of the moles needed to balance out a charge on the opposite side.

Description

Stieglitz took at least 220 photographs that he called Equivalent or Equivalents; all feature clouds in the sky. The majority of them show only the sky without any horizon, buildings or other objects in the frame, but a small number do include hills or trees. One series from 1927 prominently features poplar trees in the foreground.

Almost all of the photographs are printed very darkly so the sky often appears black or nearly black. The contrast between the sky and the much lighter clouds is striking in all but a few of the prints. Some images include the sun either as a distinct element in the photograph or as an illuminating force behind the clouds.

Background

The multiple series Stieglitz called Equivalents combined two very important aspects of his photography: the technical and the aesthetic. He was a master at both, but with Equivalents he succeeded in bringing his skills to a new level. On the technical side, Stieglitz had been fascinated by the special problems of photographing clouds ever since the summer of 1887, when he took his first pictures of clouds over Lake Como in Italy. Until the 1920s most photographic emulsions were orthochromatic, which meant they were primarily sensitive to light on the blue end of the spectrum. This made photographing clouds particularly difficult because unless special filters were used the sky would appear very light and the clouds would be lost against it.[2] Over the years Stieglitz repeatedly took photographs of clouds using orthochromatic emulsions, but he reported "Every time I developed [a cloud negative] I was so wrought up, always believing I had nearly gotten what I was after – but had failed."

In 1922 Stieglitz read a commentary about his photography by Waldo Frank that suggested the strength of his imagery was in the power of the individuals he photographed.[3] Stieglitz was outraged, believing Frank had at best ignored his many photographs of buildings and street scenes, and at worst had accused him of being a simple recorder of what appeared in front of him. He resolved immediately to begin a new series of cloud studies "to show that (the success of) my photographs (was) not due to subject matter – not to special trees or faces, or interiors, to special privileges – clouds were there for everyone…" He said "I wanted to photograph clouds to find out what I had learned in forty years about photography. Through clouds to put down my philosophy of life –…My aim is increasingly to make my photographs look so much like photographs that unless one has eyes and sees, they won't be seen – and still everyone will never forget them having once looked at them."[4]

Coincidentally at this same time a new panchromatic photographic emulsion was developed that allowed the full range of colors to be captured. Soon after it became available Stieglitz aimed his 8 in × 10 in (200 mm × 250 mm) view camera at the sky and began taking pictures. By the next year he had created a series of ten mounted photographs he called Music: A Sequence of Ten Cloud Photographs (also called Clouds in Ten Movements). He told his wife Georgia O'Keeffe "I wanted a series that when seen by Ernest Bloch (the great composer) he would exclaim: Music! Music! Man, why that is music! How did you ever do that? And he would point to violins and flutes, and oboes, and brass…"[5] He first exhibited this series in 1923 in his one-man show at the Anderson Galleries in New York, and reported that when Bloch saw them there he had exactly the reaction Stieglitz had wanted.[6]

Encouraged by the success of the Music series he took his smaller 4 in × 5 in (100 mm × 130 mm) Graflex camera and shot dozens of pictures of the sky in the summer of 1923. He arranged many of these photographs into distinct series he called Songs of the Sky. In late 1924 he exhibited sixty-one of his cloud photos in a single room at the Anderson Galleries. In the catalog to the exhibition he wrote "Songs of the Sky – Secrets of the Skies as revealed by my Camera are tiny photographs, direct revelations of a man's world in the sky – documents of eternal relationship – perhaps even a philosophy."[7] After seeing the exhibition, Ananda Coomaraswamy, who was then curator at the Museum of Fine Arts in Boston, persuaded Stieglitz to donate some of his photographs, including five from Songs of the Sky, to the museum. This was the first time a major museum in the U.S. acquired photographs as part of its permanent collection.

Stieglitz continued photographing clouds and skies for most of the next decade. In 1925 he began referring to these photographs as Equivalents, a name he used for all such photographs taken from that year forward. In 1929 he renamed some of the original Songs of the Sky as Equivalents, and these prints are still known by both names today.

Dorothy Norman once recorded a conversation between Stieglitz and a man looking at one of his Equivalents prints:

Man (looking at a Stieglitz Equivalent): Is this a photograph of water?
Stieglitz: What difference does it make of what it is a photograph?
Man: But is it a photograph of water?
Stieglitz: I tell you it does not matter.
Man: Well, then, is it a picture of the sky?
Stieglitz: It happens to be a picture of the sky. But I cannot understand why that is of any importance.[8]

Stieglitz certainly knew what he had achieved in these pictures. Writing about his Equivalents to Hart Crane, he declared: "I know exactly what I have photographed. I know I have done something that has never been done…I also know that there is more of the really abstract in some 'representation' than in most of the dead representations of the so-called abstract so fashionable now."[9]

Artistic importance

The Equivalents are sometimes recognized as the first intentionally abstract photographs, although this claim may be difficult to uphold given Alvin Langdon Coburn's Vortographs that were created almost a decade earlier.[10] Nonetheless, it is difficult to look at them today and understand the impact that they had at the time. When they first appeared photography had been generally recognized as a distinct art form for no more than fifteen years, and until Stieglitz introduced his cloud photos there was no tradition of photographing something that was not recognizable in both form and content. Art critic Hilton Kramer said that Equivalents "undoubtedly owe something to the American modernist painting (Dove's and O'Keeffe's especially) that Stieglitz felt particularly close to at the time. Yet they go distinctly beyond the pictorial conventions that governed avant-garde painting in this period by reaching for the kind of lyric abstraction that was not to enter American painting until the 1940s and 1950s. In the line that can be traced from the paintings of Albert Pinkham Ryder to, say, those of Clyfford Still, it is in Stieglitz's Equivalents – rather than in painting itself – that we find the strongest link."[9]

One of the reasons that the strongest of these photographs appear so abstract is that they are void of any reference points. Stieglitz was not concerned with a particular orientation for many of these prints, and he was known to exhibit them sideways or upside down from how he originally mounted them. Photography historian Sarah Greenough points out that by doing so Stieglitz "was destabilizing your [the viewer's] relationship with nature in order to have you think less about nature, not to deny that it's a photograph of a cloud, but to think more about the feeling that the cloud formation evokes."[11] She further says:

"The Equivalents are photographs of shapes that have ceded their identity, in which Stieglitz obliterated all references to reality normally found in a photograph. There is no internal evidence to locate these works either in time or place. They could have been taken anywhere—nothing indicates whether they were made in Lake George, New York City, Venice, or the Alps—and, except for the modern look of the gelatin silver prints, they could have been made at any time since the invention of photography. And because there is no horizon line in these photographs, it is not even clear which way is 'up' and which way 'down.' Our confusion in determining a 'top' and a 'bottom' to these photographs, and our inability to locate them in either time or place, forces us to read what we know are photographs of clouds as photographs of abstracted forms."[12]

New York Times art critic Andy Grundberg said The Equivalents "remain photography's most radical demonstration of faith in the existence of a reality behind and beyond that offered by the world of appearances. They are intended to function evocatively, like music, and they express a desire to leave behind the physical world, a desire symbolized by the virtual absence of horizon and scale clues within the frame. Emotion resides solely in form, they assert, not in the specifics of time and place."[13]

Photographer Ansel Adams said Stieglitz's work had a profound influence on him. In 1948 he claimed his first "intense experience in photography" was seeing many of the Equivalents (probably for the first time in 1933, when they met).[14]

Series and sets

Stieglitz arranged the photographs he called Equivalent into several different groups when he exhibited or published them, and often he inscribed the mounted prints on the back with one or more letters to further identify what he called "sets". These groupings are not sequential, and Stieglitz did not consider any single series or set as a discrete unit. Some of the individual prints are included in more than one series or set, and some copies of the same print are inscribed with different identifications. In general, his sets should be seen as "totally artificial constructions which mirror, not the passage of real time, but the change and flux of Stieglitz’s subjective state."[12]

The following is a chronological listing of the Equivalents photographs. Many of the prints do not have individual titles, and dozens of photographs are known by the same generic name Equivalent. The most comprehensive catalog of these photographs is found in Alfred Stieglitz: The Key Set.,[15] and the numbers in this list refer to the photographs identified in that publication.

  • 1923 – Songs of the Sky "W" / Equivalent "W" – two prints (Key Set #950-951). These prints were originally part of the Songs of the Sky series, but in 1929 Stieglitz renamed them Equivalents. These are not the same prints as those belonging to "Set W" taken in 1929.
  • 1923 – Songs of the Sky "XX" / Equivalent "XX" –four prints (Key Set #952-955). These prints were originally part of the Songs of the Sky series, but in 1929 Stieglitz renamed them Equivalents. These are not the same prints as those belonging to "Set XX" taken in 1929.
  • 1923 – Songs of the Sky / Equivalent – thirty-four prints (Key Set #956-989). These prints were originally part of the Songs of the Sky series, but in 1929 Stieglitz renamed them Equivalents.
  • 1925 - Forty-five prints (Key Set #1093-1137)
  • 1926 - Twenty prints (Key Set #1159-1178)
  • 1927 - Ten prints (Key Set #1198-1207)
  • 1928 - Twenty-seven prints (Key Set #1208-1239)
  • 1929 – Set B: two prints (Key Set #1282-1283)
  • 1929 – Set C2: five prints (Key Set #1253-1257)
  • 1929 – Set HH: three prints (Key Set #1258-1260)
  • 1929 – Set K: three prints (Key Set #1261-1263)
  • 1929 – Set O: seven prints (Key Set #1264-1270)
  • 1929 – Set W: five prints (Key Set #1277-1281)
  • 1929 – Set XX: nine prints (Key Set #1284-1292)
  • 1929 – Thirteen prints ("Key Set" #1293-1305)
  • 1930 - Twenty prints (Key Set #1330-1349)
  • 1931 - Fifteen prints (Key Set #1412-1426)
  • 1933 – Three prints (all from one negative) (Key Set #1512-1514)
  • 1934 – Six prints (Key Set #1558-1563)

Notes

  1. ^ Hirsch, Robert (2000). Seizing the Light: A History of Photography. NY: McGraw-Hill. p. 239. ISBN 0-697-14361-9.
  2. ^ "Orthochromatic Photography". Retrieved 2008-12-26.
  3. ^ Richard Whelan (1995). Alfred Stieglitz: A Biography. NY: Little, Brown. pp. 431–432. ISBN 0-316-93404-6.
  4. ^ Alfred Stieglitz (19 September 1923). "How I came to Photograph Clouds". Amateur Photographer and Photography: 255.
  5. ^ Waldo Frank, ed. (1934). America and Alfred Stieglitz: A Collective Portrait. NY: Literary Guild. p. 154.
  6. ^ Lowe, Sue Davidson (1983). Stieglitz: A Memoir/Biography. NY: Farrar Straus Giroux. p. 257. ISBN 0-374-26990-4.
  7. ^ Stieglitz, Alfred (1923). Catalog of the Third Exhibition of Photography by Alfred Stieglitz. NY: Anderson Galleries.
  8. ^ Dorothy Norman (1984). Minor White, A Living Remembrance. Aperture. p. 9.
  9. ^ a b Kramer, Hilton (1982-12-19). "Photography as High Art". New York Times. p. 1. Retrieved 2008-12-26.
  10. ^ "Alvin Langdon Coburn, Selected Photographs from the Collection of the National Gallery of Art". Archived from the original on 2014-08-08. Retrieved 2014-08-02.
  11. ^ Greenough, Sarah (1995). Mark Greenburg (ed.). In Focus: Alfred Stieglitz; Photographs from the J. Paul Getty Museum. Los Angeles: J. Paul Getty Museum. p. 132.
  12. ^ a b Greenough, Sarah; Juan Hamilton (1983). Alfred Stieglitz: Photographs and Writings. Washington: National Gallery of Art. pp. 24–25. ISBN 0-89468-027-7.
  13. ^ Grundberg, Andy (1983-02-13). "Photography View: Stieglitz felt the pull of two cultures". New York Times. Retrieved 2008-12-26.
  14. ^ Phillips, Sandra. "Adams and Stieglitz: A Friendship". Art in America. p. 1. Retrieved 2008-12-26.[dead link]
  15. ^ Sarah Greenough (2002). Alfred Stieglitz: The Key Set. NY: Abrams. ISBN 0-8109-3533-3.

External links

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