Dallmeyer 10x8 Rapid Rectilinear Lens

[Kurtay Photography]

Hi All

I have just got this lens (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWNX:IT&item=150316549564) on Ebay and I was wondering if anyone else has one and uses one of these lenses. I have done a test on my 10x8 camera and result was rather pleasing and the image looked quiet sharp and soft in contrast. I believe they are from 1866 and the one I have is a f6 portrait version. I was wondering what the aperture was as there is no indication on the lens and I googled to find it out. Then I noticed that there are no photographs on the net made with using one of these lenses. I was surprised to see that such an history and no samples..!

I am posting my one here and hope to see more of these samples from the other users.

21111

Thanks
Kurtay

[Glenn Thoreson]

There are lots of posts here on Rapid Rectilinear lenses. Perhaps not the same brand but the Rapid Rectilinear is what it is in about any flavor. I'm a little puzzled about the f/6 aperure, though, which would usually be an Aplanat. I'll bet our friend Ole knows. :D

[BarryS]

I have the next size up--a 12x10 Dallmeyer Rapid Rectilinear. It's a 16" focal length at f/8. It's a lovely little lens--almost perfect for 8x10 portraits. I find mine very sharp in the center with some very gradual falloff in sharpness and very soft bokeh. Are you sure your lens isn't f/8? Did you measure the focal length from the waterhouse slot?

[Brian Stein]

Id be interested in Ole's expertise but my understanding is that the f6 portrait lens was a petzval, the RR potrait was an f4, and that the generic RRs were f7.7 or f8. The engraving here is pretty clearly RR, so I think you have a 13" f8 RR. In any event you seem to be putting it to good use!

[Kurtay Photography]

Thanks guys for all the input... Well, I have a
210mm Berthiot Paris Stellor 1b Serie No:6 f4 lens (http://i333.photobucket.com/albums/m386/kurtayphotographer/BerthiotParisStellor10x8.jpg) and looking at that I have put the two lens side by side and the diameter of the both lenses are only marginly different RR being smaller. Then I read on the internet that some of these lenses were built in f6 rather than f8 and another information says this lens is f8! CONFUSING! I have done my assumption on according to f6 when I took the photo and the negative looked right (I guess).

I have measured the lens from waterhouse to front is 34mm (1"1/4) and the front diameter of the glass is 45mm (1"3/4). The lenght is 65mm (2"1/2) long.

More info will be useful on this beauty. Also, what is the story on Aplanat lenses?

Thanks
Kurtay

[Brian Stein]

IIRC aplanat is the designation from most of the European makers for a rapid rectilinear.
These were offered in a variety of forms: wide angle ~f12-16, the standard f7-8 covering about 70 degrees, a portrait aplanat at f4-5.5 with more even coverage than petzvals but narrower than std, detective aplanats at f6 or so, and a portable around f11. You are starting to become a lens vade mecum target audience!

The stellor is an aplanat, so part of the next generation of lenses. Dont know much about them but prob. 1920s onward, triplet design.

[Ole Tjugen]

Rapid Rectilinear was the British name for what Steinheil named Aplanat.

All else being equal, they can be considered to be just the same.

Portrait Rectilinears/Aplanats were often f:6; "normal" or "Universal" anywhere from f:7.2 to f:8, "Landscape" around f:10, and wide angle around f:14 to f:18.

An f:6 portrait lens is likely to be a RR or Aplanat. Much faster than that, and it's far more likely to be a Petzval.

Just remember that there were several different aperture scales in use at the time, so that what is really f:8 can be marked as 4, 64, 1, or just about any other number...

[Kurtay Photography]

Hello Again

Thanks for the further information...

For the record of a lens vade mecum, is this Dallmeyer RR a f6 lens? ;-)

Cheers
K

[BarryS]

Since the 10x8 RR is a 13" (330mm) lens, the diameter you measured makes it no faster than an f/8 lens. If the front glass is 45mm in diameter, once you subtract a bit for the diameter of the Waterhouse stop opening it would probably be closer to 41 mm.

330mm/(45mm-4mm)=~ f/8