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View Full Version : Finding and Fitting a Brass lens hood for a deserving Petzval



Steven Tribe
1-Mar-2015, 07:16
I had already made a temporary brass lens hood for this large fast 1850's Waibl. But it didn't match the slightly later versions shown in the "austrian photohistoric index". They have the traditional flange with a thread matching a thread on the barrel, which means the diameter of the lens hood is more than a centimeter large in diameter.

There are occasional listings of large "orphan" lens hoods on Ebay. These are mostly with male mounting threads - the more modern way of mounting brass hoods. I bought a large male hood early in february, which would be big enough to convert for my purpose.

Co-incidentally, this hood must have come of a Suter Portrait Petzval no. 4 as it matches in everyway with the hood of this lens which I have!.

The cutting of the hole (thereby removing the thread section, was done with ordinary (PRC) saw, after a drill (1.5mm) created an entry slot. Slight adjustment with a file.

I was expecting to use small tracks of soft solder at 3 positions in order to cut some retaining sections of thread. However, the fit so perfect that it could just be eased on, with a slight flexing of the hood to compensate of ovality. It can only be removed now through flexing (compression) in a particular way. The flexing ability is made possible because the large diameter.

Time

bore holes - 5 minutes.
saw round the circumference - 10 minutes.
File the cut hole - 30 minutes.

All done when my wife was at a Ceramics Workshop to-day and she hasn't come home yet!

Now she is home!

Steven Tribe
2-Mar-2015, 04:06
The sequence of Photos is a little confusing! The last image (previous posting) is of the male lens hood. the second is the completed mounted hood and the "waste" male thread.

The first new photo here is the Waibl without the new lens hood and the mountable lens hood and the last one shows what the previous DIY brass hood looked like.