lens names under each image...
lens names under each image...
Fantastic, just what we need a series visually explaining SF
Thank you!
Tin Can
you're welcome -
just a few more of my favorites...
Names are basically ways manufacturers came up with to try to differentiate their lenses. But a Darlot hemispherique rapide is just a Rapid Rectilinear. They used that name because they were french, and it sounded good. The rest of Europe called them Rapid Rectilinears or Aplanats. All the same design, and pretty much the same look.
It's not "simply slower than a petzval." A RR is the lens that replaced the Petzvals in a lot of portrait studios. They were used, along with Petzvals, for portraits for 30 years, until the better corrected Anastigmats came out. So that's the difference, a petzval, though the sharpest in the center, has a curved field, which makes things go out of foucs towards the edges. A RR does not, but still has other aberrations like astigmatism. The Zeiss designs around the mid 1890s corrected even that. Interestingly, though the anastigmats replaced the Rapid Rectilinears, which quickly became obsolete and were no longer made, they did not replace quality portrait Petzvals. Those continued to be made another 30 years. The RRs had no advantage over a Dagor, Tessar, or Protar. But the Petzvals did.
Individual RRs will have slightly different looks, but all have a fairly flat field, and usually are around F6 to F8. Slower than a Petzval, but with less concern that the edges would be out of focus, if shooting groups. Yet Petzvals don't have to go out of focus at the edges, if you use a long enough one. If a head and shoulder shot, with a studio background, and using a correctly sized Petzval, it will give a similar look as an RR, just have shorter depth of field. No swirls, no edge aberrations. But for 8x10 you'd need at least a 14" or 16" one. People today try to get by with 12" ones, or use foliage as a background. Hence, swirls.
You can review portraits shot by various lens on a lot of sites like here, and choose what look you want. Instead of what sound! https://www.flickr.com/groups/lf-portrait/
Garrett
flickr galleries
Newly made large format dry plates available! Look:
https://www.pictoriographica.com
That's unfortunate. Most of the machinists I've worked with were old school machinists. I had the good fortune of learning my way around a shop under the tutelage of a Navy machinist with something like 40 years' experience (and no missing fingers).
Part of that experience included learning how colorful the English language can be when put to use by veteran Navy personnel. Unfortunately, the only thing that particular experience gets me now is in trouble with my wife when I forget that the kids are in hearing range!
Newly made large format dry plates available! Look:
https://www.pictoriographica.com
The Darlot I have is... well ... a Darlot, they didn't have model numbers other than what they are classed under in old catalogs,
it's a petzval design and 8" focal length. I didn't see much swirly on an 8X10 compared to the 10" Seroco lens I have, but I haven't had a chance
to test it with the waterhouse stops I made, if there are swirlies the waterhouse stops will probably dull the effect depending on the f stop.
Cameraeccentric's site is a great place to start by looking thru the old catalogs, Gandolfi posted some great examples,
I might relapse into brass fever again because of his pictures, and CCHarrison and Garrett gave a great explanation of the lens type/names
and what design style they are, you need to narrow down what you want and work from there.
Bookmarks