From The Spectator (London) No. 689 (11 September 1841) pp. 877-878:

8th September 1841.

SIR—I have read in your number of the 4th instant an article entitled "Photographic Miniatures." In which, after comparing my process with that of Mr. Beard, you conclude that the portraits taken by Mr. BEARD are superior to mine. As your remarks may leave an unfavourable impression on those who have not had an opportunity to compare the two processes, I hope you will admit into your next number a few observations, which I wish to submit to your impartiality and to the good sense of the public.
    You have stated that Mr. BEARD�S process is shorter than mine. On what data have you grounded this opinion? Have you ascertained the exact time taken by Mr. BEARD�S process and mine—at the same hour, with the same state of the atmosphere, during the same day, and in the same month? If you have witnessed Mr. BEARD�S process in June and mine in August, of course you must have found a considerable difference in the time of the two operations. The fact is, that in June I operated in 10 to 20 seconds; in July, in 20 to 40 seconds; in August, in 40 to 60 seconds; and now, in September, in 60 to 90 seconds. This is about the proportionate average according to the power of the sun�s rays and the clearness of the atmosphere in those respective months; influences that must be submitted to by all Daguerreotypists.
    You also state that my process for fixing the picture, which is peculiar to myself, is not so very important; and that Mr. BEARD�S portraits have not altered by being exposed several months to the light. In this you are again mistaken. My mode of fixing is of the greatest importance, because my portraits so fixed may be rubbed with any soft substance without sustaining the least injury, in order to clean them when covered with dust, &c.; and were it not for this mode of fixing, the slightest touch would take off the light film that forms the image upon the silver plate. Assuredly the process of fixing cannot be considered as an unimportant improvement.
    Your comparison of Mr BEARD�S mode of reflecting the image by a concave mirror, whilst I make use of an achromatic lens, shows that you are fully conversant with the optical part of the Daguerreotype. You state very correctly that the former gives an image larger at the circumference and smaller at the centre, and that the latter renders it larger at the centre and smaller at the circumference. You acknowledge at the same time, very justly, that the distortion is greater in Mr. BEARD�S process and less in mine. This, Sir, is the best acknowledgement that can be given that my process is not inferior to Mr. BEARD�S; for in point of portraits, the less the distortion of the features the better the likenesses. However, I have a new arrangement for the optical part of my process, by which the spherical aberration is almost completely corrected; whilst such an improvement cannot be made with the reflector.
    With respect to your observation that my process gives an inverted image and Mr. BEARD�S a right one, I am sorry that you have not been aware that my apparatus is furnished with a parallel mirror, by which I can at will take a portrait in either way. It is true, I seldom make use of the mirror; because I have found, that when I did employ it for the same sitting, in one apparatus, whilst the other apparatus was without it, no difference in the likeness was observed by the parties. Nevertheless, I make use of the parallel mirror whenever I find faces not alike on both sides, or that have some peculiar defect. It takes a little more time when I make use of the mirror, although this is now a consideration of trifling importance, particularly since I can electrotype my portraits so as to obtain as many fac-similes of each portrait as are required; and these reproductions by the electrotype process are as perfect and as beautiful as the original Daguerreotype portrait. Of this admirable and unlooked for application of the two self-acting processes, as perfect as nature, I send you a specimen for your inspection, showing the same portrait in duplicates; and you will observe, that as the faces look towards each other, one must be inverted and the other right. Copies may be repeated to any number without injuring the original; and each copy can serve to produce other copies without weakening the first picture.
    You say Mr. BEARD�S portraits are superior to mine, I think I have the right to complain of such a statement, inasmuch as you have not been able to see many of the portraits I have produced; and if you have seen a greater number of Mr. BEARD�S better than mine, it is because Mr. BEARD has had the time to produce several thousands since the beginning of the year, and that I have hardly yet had a fair chance, in the course of three months, of producing a few hundreds; nor have I had the leisure to produce may portraits for show, the better specimens being invariably away by the owners. Moreover, I had hardly begun taking likenesses, when I was disturbed by a suit in Chancery instituted against me by my very opponent.

I am, Sir, your obedient servant, A. Claudet.

[We willingly insert M. CLAUDET�S polite and explicit communication respecting his process of taking Photographic Miniatures; as our only object in making a comparison of his and Mr. BEARD�S was to explain the differences between the two, and to place their relative merits fairly before the public. His letter supplies new information on one or two points.
    So far as regards the differences in time, it is not very material; and we stated that "it was about equal in both cases," taking into account the production of two miniatures. That Mr. BEARD�S is absolutely the quickest for producing single likeness, appears form M. CLAUDET�S statement; since we saw two or three portraits taken at the Polytechnic Institution in from four to seven seconds on a bright day. With reference to the fixing-process of M. CLAUDET, it is impossible to overrate the importance of a preparation which admits of particles of dust being wiped off from the surface of the plate; but we were not aware that the miniatures taken M. CLAUDET admitted of the application of this test without the subsequent operation of gilding.
    The use of the parallel mirror by M. CLAUDET is also new to us; and we should consider it to essential in every case, for the two sides of the face are not exactly alike in any individual countenance. That the reversal affects the resemblance was evident in one instance where we had an opportunity of comparing the portrait with the original; the difference between the two miniatures of the same person sent by M. CLAUDET, one reversed the other not, is also evidence of the fact.
    The application of the Electrotype to multiplying photographic miniatures is equally curious and valuable; and increases the utility of the Daguerreotype as a means of portraiture.
    Our opinion of the relative merits of the two processes was formed from a careful examination of the results of both, as shown in a variety of specimens, good, bad, and indifferent; most of which, we were told, had been rejected; but on the point of executive beauty the public may judge for themselves, by comparison.]

(End of text. Please refer to our textnote regarding this text.) This text is a rebuttal by Claudet to a previous text published in September 4, 1841 edition of The Spectator.