A DEMONSTRATION OF A CLAUDE GLASS (scroll down to see the photos)


  • The Claude Glass or (Lorrain Mirror) is a small black mirror used as a drawing aid by artists.

  • For viewing sunlit scenery; artists could work with less eyestrain.

  • Named after Claude Lorrain, the French painter who was thought to have invented it (disputed). 

  • 18th century tourists used Claude glasses when looking at scenery.

  • Real landscapes reflected in it were judged by how much they resembled a painting by Claude Lorrain. 

  • It is optically ground to display a wider scene than a flat mirror of the same size.

MY PHOTOS WERE TAKEN IN 2001 to demonstrate what an image reflected in a Claude mirror looks like. I had noticed that online reference sites described Claude reflections as "sepia" or "neutral" or "monochrome". This was a misunderstanding as, presumably, the entry writers had not seen one in use.

Drawings executed with the help of a Claude glass were often monochrome but the reflections seen in a Claude glass are not. 


I took the pictures using my Claude glass and put up an Apple Homepage website to show them. One photo was edited to monochrome to resemble the erroneous notion of a Claude glass reflection.


LOCATION I chose Calton Hill in Edinburgh because the grand, classical monuments there are the kind of motif that attracted early users.


PURPOSE You can see from my photos that a Claudian mirror shows full colour scenes without dazzle, allowing  such qualities as the rounded shapes of clouds to be appreciated.              


After I contacted the editor of an online reference work devoted to scientific instruments, he viewed my site and emailed me to thank me for my demonstration of the Claude; he adjusted the relevant entry to take account of the new information! I wish I could remember what the site was called; I do not know if it is still online.


The "Claude Glass" is a black, optically ground, convex mirror said to have been invented by the French painter Claude Lorrain in the seventeenth century although that historical belief is denied today by art historians who say there is no evidence for it. "Optically ground" means that if you place a Claude glass beside a flat mirror of the same size, you will see that the Claude displays a broader field. I think it is the case that the glass of a real Claudian mirror is dark throughout and not simply clear glass with a black backing.


FASHIONABILITY The Claude glass was made fashionable in the English-speaking world by the poet Thomas Gray and William Gilpin, the theorist of The Picturesque. Using the Claude glass, artists and travellers were able to study intensely bright, sunlit scenes at length without eye strain, clearly make out shapes and details, work out the scale of tones and use their analyses to construct drawings and paintings (and verbal descriptions); the leisured could comfortably spend time looking at scenes which attracted them. It occurs to me that meteorologists might have found the Claude glass a help in the then-new study of clouds.


Claude glasses went out of fashion around the middle of the nineteenth century probably due to the hostility of John Ruskin who criticised them in "The Elements of Drawing" because they falsified tones; he wanted artists to work directly from nature. Around that time, photography was replacing some functions of drawing by hand and Ruskin also warned about the dangers to artists of photography: the shadows in a photo were too dark by a factor of four in his calculation. His ideas were taken up by the French Impressionists who referred to him with admiration. I had always thought that the artists who used a "claude" were professional painters or engravers but some writers insist that they were used by amateurs only. I don't know whether Claudes have been found in the inventories of professional artists (including engravers) of the 17th, 18th and early 19th centuries.


NAMES I refer to the instrument in various ways, in part to match different Internet searches and also due to my uncertainty as to how it should be referred to (capitalisation and synonyms).


 INTERPRETATIONS Today, there is a school of thought which is interpreting the "Claude" in new ways, e.g. as an 18th century kind of Instagram: "the English were once forward looking, inventive and curious as a nation, and so they came up with their own way to grungify the views they saw on vacation, and (probably) their breakfasts" (from the Web). Instagram is a feature of modern leisure but such interpretations miss the point of what the original users were about. The modern pastime of "filtering" digital images to make them look like products of various obsolete imaging technologies was not what eighteenth century users of these black mirrors had in mind; there was no pre-existing database of billions of images awaiting "filtering" by Instagram; making an image was the problem and that could only be done by eye and hand and several visual aids.


After the "Claude" fell out of use, people who came across them possibly thought they were spoiled, blackened mirrors or photographs on glass and threw them away. That was my first thought when I saw one at an uncatalogued auction preview before I realised what it was.  


PROVENANCE OF THIS INSTRUMENT I was able to buy mine cheaply at the weekly "Wednesday Hall" sale devoted to dispersing household goods at the old Lyon & Turnbull between Thistle Street and Thistle Street Lane parallel to George Street in Central Edinburgh. No one else there seemed to know what it was and I jumped with surprise when it was "knocked down" to me at a very low price. Claudes were never common; in their heyday they were required only by wealthy connoisseurs of  landscape who were sometimes amateur artists and perhaps by professional painters and engravers.


SHAPE AND SIZE  I speculate that professional topographical artists might have needed the larger, almost cumbersome, rectilinear examples whereas a Lady might only have carried a pretty, little, oval one. My Claude glass has a format which puts me in mind of engravings of towns.


THE CAMERA I used was an entry-level Kodak digital camera. The capacity of such a retail consumer camera and the picture size allowed on photo-sharing sites like Homepage were both less than is common now so my pictures are quaintly "pixellated". After Homepage closed, these pictures have been hosted on other Apple picture servers but, as those have shut down too, they are now hosted here.


THE CASE is stamped underneath: "Elliott Brothers Opticians 56 Strand London” under a Royal Coat of Arms. According to www.gracesguide.co.uk, "Elliott Brothers; Opticians; 56 Strand; London" traded under this style at this address from 1853 to 1858.


SIZE: 6 1/2 x 5 1/2  x 1 inches.


APPEARANCE: Dark greenish leather, pink silk lining.


July 2015:

 I hired this Claude glass to Spun Gold TV who have made the gardening programme "Titchmarsh on Capability Brown" for Channel Four in which Alan Titchmarsh oversees and discusses the restoration and completion of the gardens at Belvoir Castle, seat of the Duchess of Rutland, following the rediscovered plans which were drawn up by "Capability" Brown. Spun Gold wrote to me that "the sequence we filmed with Alan using the Claude Glass went really well! It really brought something extra to the series, we can't thank you enough for allowing us to use it. This sequence will be shown in the final of 3 episodes".

6th Feb 2017:

I am delighted to say that I have hired this claude to a second TV production company, Oxford Film and Television. The programme is about art and industry and has been commissioned by BBC Four.

PS: this page by James Gurney, the creator of Dinotopia, is interesting.