My dear Sir
Many thanks for your beautiful Talbotypes. <1> I hardly know which to give the preference to they are all so fine. –
There is a remark that has often occurred to me in looking at photographic pictures from nature viz: that they are hardly one in fifty perspective representations on a vertical plane. In consequence perpendicular lines all converge upwards or downward wh is a great pity. – Now it is so easy to avoid this by attaching a small level to the camera box, adjusted by trial so as to bring the picture right in the horizontal portion of the box level that is seems quite a necessary part of the apparatus.
But it is true that in that case the Points of Sight would being always in the horizon line, nearly half the best part of the field of the lens would often be sacrificed. Still when a high station can be chosen this is not the case & this is a reason for chusing a station half way up to the height of the principal object to be represented.
I remain My dear Sir Yours very ty
JFW Herschel
Notes:
1. These were calotypes made both by WHFT and friends. See Doc. No: 06016. Although WHFT preferred the term calotype, Herschel and other friends sought to honour the inventor by naming his process after him, in parallel with the Daguerreotype.