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Shen45
9-Oct-2007, 22:05
Today with time on my hands I found I had a set of Wollensak Petzval barrels with the same internal thread as my Alphax #4 shutter.

I took the rear element group of a 305mm Raptar [Dialyte] and put it on the rear tube, [straight fit, exact threads] on the front I left the Petzval front group in its barrel. Between these barrels sits a studio shutter.

The image on the GG is very smooth sharp - a slight glow and nice OF areas.

Combined the lens has a focal length of about 229mm at infinity, the same as the original Petzval.

Meant to add I will take some images over the next day or so.

Ash
10-Oct-2007, 00:19
Sounds great. I'm doing similar, ripping lens elements out and seeing what effect I can get by mis-matching. Of course I'm not as lucky as you :D

walter23
10-Oct-2007, 01:53
I discovered that a +2 eyepiece diopter from a nikon camera makes a fun little 320mm f/16 lens for my shenhao 4x5. Requires front standard gymanstics (rear tilt forward & axis tilt backward) even for infinity work, but I can get enough extension for about 10 to 15 foot minimum focus.

Makes me want to buy glass elements and try putting them together in interesting combinations. Will have to read up on some basic optics first.

Here's the only thing developed from it so far (just a quick test I ran off during a 30 second window of light between cloudiness and sunset). Just a standard black & white tree shot with a novel lens, nothing good. I have a bunch more interesting stuff exposed and awaiting processing.
http://ashphotography.ca/zenphoto/albums/ghetto-lens/Untitled-1.jpg

Ash
10-Oct-2007, 02:07
Walter go to your local (good) camera shop where they have loads of second hand lenses.

Pick yourself up the longest focal length 35mm lens in the fattest barrel. The bigger and uglier the better. Usually the front elements are nice and long 'f' with a very bright 'f/'.

I've done this a few times,

Enlarger condensers - http://i2.photobucket.com/albums/y43/second-belated/aUntitled-1b.jpg

Hanimex 300mm - http://i2.photobucket.com/albums/y43/second-belated/Untitled-1copy-1.jpg and http://i2.photobucket.com/albums/y43/second-belated/Untitled-9a-1.jpg

And I also have a really nice telephoto zoom lens that's awaiting a test shot from the front element.

Shen45
10-Oct-2007, 03:42
Walter and Ash, this is a Verito backend with a Petzval back end.

I will look forward to some of the creations people come up with. Maybe a whole new market for the "little green men"

walter23
11-Oct-2007, 10:20
Nice effect Steve.

jb7
2-Dec-2007, 17:23
Nice pictures-

This is one I tried last week using a condenser from an old spotlight-
about 5" diameter, about 5" focal length-
Looks like my only f/1 lens-

Taped to a copal 0 lensboard makes it about f/4-

joseph

rippo
2-Dec-2007, 21:55
jb7, that's a really awesome portrait! something i'm striving for with my homemade lenses, but still in the 'trial' phases.

jb7
3-Dec-2007, 06:34
Thanks Matt-

Nice of you to say so-
Though this is more of a readymade than an experimental lens,
as described above-

Really need to get a Packard shutter to do this properly;
how come Photography is such an endless shopping list?

I've got an old Nikkor 135 f/2,8,
but having difficulty removing the front element-
I've already taken an angle grinder to the mount for another project,
but don't want to use the same method near the glass-
Should it just unscrew from the front, I wonder would anyone know?


j

Alex Wei
3-Dec-2007, 13:47
wow, very interesting!