And yet Mozart scholarship doesn't even know for sure when Mozart's brother-in-law painted this portrait. In 1913 Edward J. Dent claimed that it originates from 1791. After having met sharp criticism from Téodor de Wyzewa in a review in the Revue des Deux Mondes and Edward Speyer, Dent in a later edition of his book Mozart's Operas corrected the dating to 1782. In an article in the 1926 Salzburger Museumsblätter art historian Julius Leisching assigned the Lange portrait to 1790. This dating did not gain acceptance either and in 1931 Roland Tenschert in his book Mozart. Ein Künstlerleben in Bildern und Dokumenten presented the portrait as having been painted in 1782. Otto Erich Deutsch seems to have pondered for several decades over a possible dating of Lange's work. In 1956 he dated the portrait with "winter of 1782-83, curiously describing it as "a sketch in oils, unfortunately never completed". This dating was influenced by the assumption that Lange's portrait of Mozart was somehow related to his portrait of Constanze Mozart, which since 1931 belongs to the University of Glasgow as part of the Zavertal Collection and is presumed to have been one of the two small portraits that Mozart sent to his father on 3 April 1783: "Auch folgen die 2 Portraits; – wünsche nur daß sie damit zufrieden seyn möchten; mir scheint sie gleichen beyde gut, und alle die es gesehen sind der nemlichen Meynung." ("The two portraits will follow; – I only wish that you will be pleased with them. I think they are both good likenesses and all who have seen them are of the same opinion.") Within the next five years however Deutsch changed his opinion again and in his 1961 book Mozart und seine Welt in zeitgenössischen Bildern (published as part of the NMA) he assigned the Lange portrait to 1782/83. Since then this dating has been revised by Mozart scholarship to 1789, based on Mozart's remark in a letter to his wife from 16 April 1789: "ich möchte gerne wissen ob schwager Hofer den Tag nach meiner Abreise gekommen ist? ob er öfters kommt, so wie er mir versprochen hat; – ob die Langischen bisweilen kommen? – ob an den Portrait fortgearbeitet wird?" ("I want to know if brother-in-law Hofer visited the day after my departure? If he is visiting more often, as he promised me; – Whether the Langes come by now and then? – If work on the portrait is being continued?")
I have been studying Joseph Lange's life and work for over ten years and I assume in all modesty that I have seen more of Lange's paintings than anybody else. Lange's Mozart portrait has been the object of my scrutiny for a long time and I have always been intrigued as to how its appearance and its state of preservation have changed during the last 60 years. Moreover I was always sceptic regarding its supposed "state of incompleteness", which owing to the unusually straight edges of paint on Mozart's body is at odds with many other unfinished paintings I know. Could it be that the painting was not unfinished, but represents an enlargement of an orignal small portrait which then was never completed? There is a model for this particular procedure. It turns out that this model is none other than Lange's portrait of Constanze Mozart which today is on display in Glasgow. That this painting is an enlarged version of a small portrait (previously 18 x 13 cm, now 32,3 x 24,8 cm) has long been known and has been pointed out several times in the literature, most recently in the catalogue of the 1991 Mozart exhibition in Salzburg. The irregular size of the original portrait (as shown approximately in the following picture) was caused by cutting and the obviously bad state of canvas quality on the lower left corner of the original painting. The enlargement was either sewn or glued to the original painting after it had been turned about eleven degrees to the right.
It is not known when the Constanze portrait was enlarged. Old black and white photographs, taken before a very intensive restoration of Mozart's portrait in the early 1960s, show that the painting underwent a similar treatment as the painting in Glasgow: i.e. a miniature, showing only Mozart's head was turned about four degrees to the right and inserted into a bigger canvas, which was supposed to show Mozart's upper body and the shape of a piano, but later remained unfinished. A photograph of the unrestored painting (in deplorable state of conservation), taken in 1946, eerily shows the distinct contour of the original small painting:
The original miniature, about 19 x 15 centimeters in size, looked like this (in exact size relation to the colored picture above):
I realized that the portrait is an enlargement in March 2009 which can be attested by several colleague musicologists. On 29 June 2010 I visited Mozart's birthplace and examined the Lange portrait, which at that time had been taken from the exhibition to be scrutinized by the museum staff. I told Dr. Großpietsch and Dr. Ramsauer about my hypothesis and had to realize (because the Mozarteum is a museum like no other) that there is no scholarly documentation on the 1963 restoration of the painting and the Mozarteum had never X-rayed the portrait. The restoration of course has rendered the visible distinction between the original minature and the enlargement almost imperceptible. Not only was the gaping horizontal crack that is visible on old photographs filled with putty, the edge of the brown paint at the lower end of the painted area on Mozart's chest was also horizontally adjusted, as if to hide the tilted original miniature:
Given the current state of the painting, the different canvas of the small original portrait is only discernible as a slightly lower rectangular area, when looked upon in a very flat angle in backlight. Therefore I concluded that in the course of the enlargement the small painting was mounted from behind to the larger canvas. The Mozart portrait by Joseph Lange is not an unfinished painting of "Mozart at the Piano", but an unfinished enlargement of an original miniature of Mozart's head.
What are the implications of this discovery? The original miniature portraits of Mozart and his wife painted by Lange, both of which were later enlarged, could well be the two small paintings that Mozart sent to his father in April 1783. The Mozart miniature portrait from 1782-83 is "lost", because for over 200 years it has been hidden in plain sight in the "unfinished" painting of Mozart at the piano. Constanze's small portrait was successfully resized, while the enlargement of Mozart's portrait - at some time sent back to Vienna - was never completed. That Lange had not finished the work by 1812 may well have been caused by the fact that at this time he had long separated from Constanze's sister and had started a third family with a woman 30 years his junior. The enlargement with the addition of the piano could have been the work Mozart was referring to in his 1789 letter from Dresden ("an den Portrait fortgearbeitet"). Recently some pseudo-scholars tried to cast doubt on the authenticity of the Lange portrait. Their aim was twofold: first, to boost the credibility of the so-called "Hagenauer Mozart" which simply doesn't resemble the man on Lange's painting. And second, to add probability to the absurd idea that "the man in the red frock" could have been the small portrait that Mozart sent to Salzburg in 1783. One proponent of this crude hypothesis even went so far as to visualize Mozart wearing a pigtail on the Lange portrait, which "can't be seen because of the chiaroscuro".
As a portraitist Joseph Lange was one of the best 18th-century amateur painters I have come across. He enjoyed a first rate education at the Vienna Academy of Arts and his technique, his shading, his mixture of skin tones was thoroughly professional. I have never seen any reproduction of the Salzburg Mozart portrait that really does justice to the artistry of color and glazing technique of the original. Contrary to a wide-spread misconception, caused by an entry in Joachim Daniel Preisler's diary, Lange did not give up painting in 1788, but diligently pursued this activity into his old age. Many of Lange's masterpieces, such as the group portrait of his mistress Therese Koch (1780-1851) and her three daughters, are still extant in the possession of Lange's descendants. Among the many amazing portraits by Lange the following is my favorite. P. Maurus (Franz Borgius) Stützlinger (b. 6 January 1775 Gmunden, d. 7 August 1842 Salzburg) was elected abbot of Lambach Abbey in 1812. In 1820 he was deposed owing to the abbey's complete bankruptcy. Joseph Lange's life-sized portrait of Maurus Stützlinger was painted in 1815: