Information and discussion on all aspects of British photographic history
I recently acquired a Grubb brass bound lens and I wondered if anyone could date it, I assume it is a Petzval type but would like to know a bit more. It is engraved “A2 Grubb Dublin 993” . I have put a couple of photos of it at http://tinyurl.com/hnh7nqq . It came with one stop and no flange. It seems to have a fairly short focal length and suffers with some separation of the front elements and "cleaning" marks.
There's nothing in the lens vademecum that helps with dating unfortunately.
Hi Michael, Thanks, when I search the web I find references to dates and serial numbers but can't find the actual lists. I was hoping that someone in this group might have access to the data.
I found this in the Journal of the Birmingham Photographic Society Thom. Sutton Ed. Vol III 1858 pg 154
This may or may not help.
I am looking for more.
Mr. Grubb, of Dublin, has patented a new
view-lens. In its outward form it resembles
the ordinary view-lens, that is to say, it is
nearly plano-convex, with a stop in front,
and the crown and flint lenses are cemented
together ; but the inner curve, instead of
dividing the compound lens into a double
concave of flint, and a double convex of crown
glass, divides it into a meniscus of crown,
and a concavo-convex of flint glass ;—the
crown lens being that on which the rays are
incident. In this arrangement, as in the old
form, the conditions of achromatism are
satisfied, and the radius of the field is the
same, but the new lens has less spherical
aberration than the other, and is therefore, in
an important particular, superior to it. It is
not a little remarkable that the problem of
the single achromatic view-lens should admit
of two, and only two, solutions, and that the
wont of the two should be that which has
been adopted for a number of years. We
have had our controversies with Mr. Grubb
on some points of theory in optics, but in
the matter of this new lens we fully appreciate
the improvement which he has suggested.
Unfortunately, however, it comes too late.
The Orthoscopic lens of M. Petzval accom
plishes what no single view-lens can do, viz. :
it gives an image i'BEE from distoetion.
The question between this and a single viewlens, of any form, is not one of rapidity of
action, or size of the stop ;—it lies far deeper,
and is of far greater moment ; it is a question
of DISTOETION OF THE IMAGE,—of TBUE OE
false febsfective. We cannot insist too
strongly upon this. Photography fixes the
images of the camera, but of what value is
the process if those images are false and
distorted ? Photography then becomes merely
the instrument of an untruth. The first
consideration in investigating the merits of
a lens is that of feeedom fbom distoetion.
Now, in the single view-lens with a stop in
front, the oblique pencils have great excentricity of incidence, and the distortion is very
great, straight lines are curved inwards at their
extremities, and the objects at the margin of
the picture are diminished in size as compared
with those in the centre. These evils
exist to precisely the same extent in Mr.
Grubb's new lens, as in the old one. %Ye
advise our readers therefore, to have nothisg
more to say to the single view-lens of any
form, but to use the Orthoscopic lens, ui
that only, for views ; and with respect to tit
size of the stop, we advise them on til
occasions to use the smallest stop possible,
because solarization is better avoided in thii
way, and a cleaner and better picture produ
ced. Besides, with an exposure of three
seconds, every moving figure produces a bin;
on the picture, while with an exposure 4
three minutes, a regiment of cavalry maj
gallop before the camera, and no effect be
produced upon the picture. If a view canoe*
be taken instantaneously, it matters but
little how long the exposure 13, within i
reasonable limit. A great deal too much is
made of the comparative rapidity of processes,
when absolute instantaneity of exposure is no;
With respect to Mr. Grubb's patent, ■
believe it will not hold good. In No. 33 of
this Journal, page 305, we have given tie
formula for a view-lens. It is immaterial u
that formula, whether the crown or flint gbus
receives the incident rays, but when recein^
upon the flint lens the formula gives the
ordinary view lens,—when received upon lis
crown, the lens of Mr. Grubb. Both m
included in that formula, and it only aduitf
of those two solutions.
In a letter just received from Mr. Ross, h
says, " with respect to my paper on the Petri*
lens, I can only apply myself to it at leism'
moments ; but will do my best to let JW
have it for No. 55.
If it is a "C" lens, it existed in 1861.
The Photographic Journal may 1861 pg 187
day, or to some other convenient time.
First, then, as to the apparatus.—My nega
tives are all on 12 by 10 plates, and, with the
exception of one (which was previously men
tioned in this room, and was taken with a
Ross's 8£ by 6% orthographic lens), wore aD.
taken with a Grubb's C lens—a lens which is
intended to cover merely 10 by 8 ; and I
think it will be allowed that the definition even
to the margin is all that can be desired. At
this point I may be permitted to observe that
I believe the landscape lensjw excellence is
that known as the single lens, and that, for
this purpose, it is superior to all tho new
lenses, whether orthoscopic, orthographic, or
triplet. I do not mean, in speaking of Mr.
Grubb's lens, to disparago the landscape lenses
of Mr. Ross, Mr. Dallmeyer, or any other
maker of eminence ; I am merely mentioning
tho fact that my pictures were taken with a
Grubb's lens, and that I think as highly of it
as possible for landscape work. My camera is
a folding one ; and although somewhat heavier,
I consider it superior to that known as Captain
Fowke's and to Mr. Kinnoar's, inasmuch as it
is firmer and more rigid. The tent which is
before you is that known as Smartt's ; and I
must say that, for field work, I know nothing
so efficient and convenient. I have arranged
in it some special fittings and contrivances of
my own, to which I will refer presently. I
used Ponting's collodion only, and a bath made
after his formula.
And whater this means from Neblette 1931 I think that is a British patent no.
|2574||- 1857||Improved achromat lens.
And this from
The Camera 1916 Frank Chambers Ed. Pg. 338:
The earliest form of a landscape achromatic lens used for photography,
consisted of a bi-convex lens of crown glass cemented to a bi-concave flint.
The Grubb lens, which is interesting as being the first so-called aplanatic lens,
was formed by cementing a concavo-convex flint to a meniscus crown. It was
found to work with a larger aperture and with less distortion, but of course
was not as correct in this particular, as more recent lenses of the aplanatic
form, which are not single corrected lenses, but compound ones. This sub
ject of distortion will need another chapter to make it clear to you.
Late to this topic but in case its still of interest here are my comments. You appear to have a Grubb made 'Carte de Visite or Portrait Combination' Petzval lens designed to cover or 4" x 3". Each (front and back) lens diameter should be 1 7/8". Its probably circa 1858/60 although exact dating is not currently possible. Grubb seems to have made lenses almost on a 'bespoke' basis and the mechanical designs of earlier lenses vary considerably although the Petzvals were relatively conventional.