Paul, I believe we have found that many Grubb lenses are effectively bespoke. Have you two that are exactly the same as regards both designation and dimensions? None of mine are the same despite having the same designations e.g. C lenses.Originally Posted by pgk
William
A Google Sheet works well - you can set permissions on it so you can edit it and others can just view it. Being web based you can then put a link to it in any post.
Karl French did this with the Cooke Portrait Lens Serial Numbers, and I (imitation being the sincerest form of flattery) made one for the TTH RV, RVP and CAP lenses.
If you use Excel you certainly wouldn't have any problem using a Google Sheet. You can paste your data in straight from Excel. Inserting or deleting rows is a bit different, as is copying and pasting, but it's easy to get the hang of.
(There are obviously pros and cons to Google - I have a Google account for this purpose alone!)
William. The later 'C' Patent lenses seem pretty close and as though their dimensions were at least intended to be the same. Otherwise only the Petzvals really look as though they were very similar. Most of Grubb's lenses seem to have slight differences. This even includes placement of the washer stop in relation to the glass and I wonder if there was some consideration of the user's requirements (I have a stereo lens which is far better at closer distances than at infinity for example). Flanges vary in style and depth and thread(!), the washer stop retaining rings vary as does the length of the washer stop tubes. Some lenses are heavily built and other more lightly. From the surviving ledger it is clear that lenses were batch built so perhaps each batch, which could be separated by months, simply had a machinist assigned to make the brasswork without any absolute guidance other than following a roughly dimensioned design? I doubt that we will ever know now.
Grubb lenses are intriguing because from the known and surmisable production information it appears that there was small but continuous demand for the lenses over many years - production probably spans something between 40~50 years, with the odd later specification lens appearing (the Ax being an example which was introduced around ~10 years after the patent). One thing which all Thomas Grubb's Patent lenses share is minute rice writing on the glass though.
I'll work on the spreadsheet later.
Struggling as I don't use Google but here's a pdf:Grubb Lenses.pdf
Lenses in bold have been examined by myself. Any details of known additional lenses would be much appreciated.
Thank you Paul for providing your informative list.
A quick check against my list reveals that I have two lenses with a serial number that are not on your list yet. However I have to double checked the source, before I can provide you with these.
Thanks Ron. Any info much appreciated - and pix if at all possible.
Something which might interest any owners of Grubb lenses which are missing their flange, is that Thomas Grubb seems to have been an early adopter of the 1841 Whitworth screw thread. In 1847 it was used (1.25" x 16tpi) by the Royal Astronomical Society as their standard for telescope eyepieces which is where Grubb might have got the idea from. All the Grubb flange threads I have been able to look at appear to have Whitworth form threads although diameter and tpi do vary substantiall across the lens range, and some flanges from the same designation lenses are clearly of very similar (the same) thread but are too tight/loose to be usable - bespoke and hand made using steam powered lathes led to some tolerance problems by the look of it!
So here's an oddity. This is a late Grubb lens engraved as being from Sir Howard Grubb. Dating it is not easy. It is certainly post 1883 as the London Agent's details confirm this. But it is a late lens and not far off Willeica's aluminium lens which has the highest know serial number. So its far more likely to be from the 1890s. It has been modified which is shown by the impingement on the engraving which seems to have occured when the rotary stop mechanism was fitted. But what is most intriguing is that the glass itself is inscribed with Grubb Patent and the serial number. This accords with Thomas Grubb's practice from much earlier and indicates that whilst this lens is much later (30~40 years later), it is still of the 1857 patented design. It looks very much like the glass is similar, or the same as one of Thomas Grubb's 'A' coded Patent lenses, although obviously the brasswork is completely different. As such it would have been well out of date when manufactured and superseded by newer designs some of which may have been using Jena glass and would have been of better performance. I'm intrigued to know why. Does anyone have any suggestions?
https://www.largeformatphotography.i...attach/jpg.gif
Last edited by pgk; 29-Dec-2022 at 02:44.
Very nice, Paul. This looks very similar to my aluminium Grubb lens No 5350 which has a diaphragm (starting with the RPS scale No f11.3) and orange coated glass elements. Because of the last mentioned feature, it is difficult to see if it contains the usual engraved on glass writing. However, this is obviously not a lens for the general market, but rather for some, as yet undiscovered, scientific purpose. The barrel is engraved ' Howard Grubb - Dublin- Aplanatic 12 x10 - 5350. There is no reference to a London or any other Selling Agent.
William
Hi Paul, after double checking it appears there is only one which seems to be missing in your list: nr. "3823 B3 Grubb Dublin" portrait lens.
(I have also nr. 5291 in my list, but can't find its source - so that one must be left out).
A photo of 3823 can be found in the book of Agostini page 300.
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