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View Full Version : Can't find a Kalosat diffusion lens? Make one...



Dr Klaus Schmitt
30-Nov-2009, 18:34
Well after searching for years for a Kalosat diffusion soft focus pictorial lens with no result, I finally decided to make one. I took a quartz meniscus lens of about 120mm focal length, an old lens barrel, some focusing helicoids, my camera and a dried up rose bouquet, and well, here are now some results of that contraption at various aperture settings. The lens element itself is about f4. The "diffusion" effect gets quite visible.

http://forum.mflenses.com/userpix/200911/455_Quarz_Aanastigmat_120mm_00017a_1.jpg

some crops:

http://forum.mflenses.com/userpix/200911/455_Quarz_Aanastigmat_120mm_00016a_1.jpg

Mike1234
30-Nov-2009, 18:38
SF isn't my cuppa tea but those are nice, Klaus. Care to post a "how-to"?

Dr Klaus Schmitt
30-Nov-2009, 18:50
Thanks, but the "how to" was already mentioned in my text, pretty simple and straightforward....don't expect CAD drawaings and a parts list with order numbers pleeeze ...

Mike1234
30-Nov-2009, 18:56
True enough...

Jim Galli
30-Nov-2009, 19:03
Klaus, I don't really think you'd see much if any difference between the Kalost and the Spencer. I don't have a Kalosat so I'm theorizing here, but both use the same basic lens formulae principal and I don't really know what the quartz glass ads besides some advertising hype.

Louis Pacilla
30-Nov-2009, 19:10
Hi Dr Klaus

Wonderful. Nice glow over the most important sold base. Content is lovely. Thanks for sharing .
Peace
Louis P

papah
30-Nov-2009, 20:47
Klaus, that's beautiful. Where did you find a quartz meniscus?

sun of sand
1-Dec-2009, 02:05
I like #2
#4 looks like a rather crappy ordinary "sharp" lens

Dr Klaus Schmitt
1-Dec-2009, 15:39
Thanks guys!

@Jim: well it might be only hype, but in my (limited) understanding quartz has a different (much lower)) dispersion
than ordinary glass has, so that should show in the results. In "Abels's Photographic Weekly" Hanovia Labs advertised it as:
((quote))
In a Kalosat you have more than a
"Spectral Diffusion Lens". You have a lens
capable of rendering your subject in a very
superior manner. It has qualities that are
unsurpassed in the realm of photography —
results that show soft delicacy of tone, great
breadth of effect, beautifully depicted lighting
and no flare or hajb. Delicate skin modu-
lations can be portrayed with infallible
accuracy and beauty, and retouching is re-
duced to practically the vanishing point.
These pleasing qualities and more.
((unquote))

well, so far for the sales. I haven't yet had time to make a thorough comparison of the Spencer Portland
and my homebrew "Kalosat". But isn't the Spencer a cemented achromatic meniscus whereas the Kalosat
(and the Struss Pictorial) are simple quartz menisci?

@papah: Edmund Scientific and optical surplus stores are good sources usually. I have a few spare very special
quartz lenses made by famous german lens maker Steinheil, Munich (one made from real Brasilian quartz!!)
but the focal lengths are 700-800mm, too long for me. Speed is about f8

@sun of sand: well I agree, it was to test out the effect of stopping down; of course that ends up at a fairly sharp level,
but will never reach a fully corrected modern lens of course.

Mike1234
1-Dec-2009, 16:14
Hey Doc!! No further replies to my request for more info? Oh yeah... that's right... I'm an idiot. Maybe you cerebral types should go start your own forum. We wee-minded folk aren't your cuppa tea, iz wee??:)

Dr Klaus Schmitt
1-Dec-2009, 16:23
We HAVE our own forum already found - here ... LOL

Mike1234
1-Dec-2009, 16:38
Hey Doc... I don't think you'll garner a lot of support from the average "Joe". Be as arrogant as you like but no one will like you.

Glenn Thoreson
1-Dec-2009, 18:33
I made something similar out of the front element from an old Sears Super 8 movie camera. Just glued it into the hole on a Speed Graphic board. About f/3.8, methinks. I haven't tried it with film yet, but the image on the GG looks too sharp. Maybe it'll go goofy around the edges. Only the Shadow knows. :D

8x10 user
1-Dec-2009, 19:41
Cool lens Klaus!

papah
1-Dec-2009, 22:18
SF isn't my cuppa tea but those are nice, Klaus. Care to post a "how-to"?

All you ever want to know about building your own lenses:
http://www.alternativephotography.com/books/je_exploring_simple_lenses.html

Another source is:
"Primitive Photography: A Guide to Making Cameras, Lenses, and Calotypes" by Alan Greene, available on Amazon.

Or, just Google "DIY lenses"

Mike1234
1-Dec-2009, 23:33
Thank you, Bruce.

Dr Klaus Schmitt
2-Dec-2009, 01:26
Thanks Bruce,

good sources helping to start newcomers; I haven't see that before.

@Mike: I hope that helps you to start!

Mike1234
2-Dec-2009, 02:32
Thanks, Klaus. Yes, it's an interesting read. And sorry for my earlier post.

csant
2-Dec-2009, 07:07
But isn't the Spencer a cemented achromatic meniscus

Yes it is.

Steven Tribe
2-Dec-2009, 09:23
I was in Edmonds (website) last night and they have quite a selection of lenses of 2 inches diameter which would fit very well in the more common smaller petzval projection barrels from around 1900. I have sure a lot of us have these with one of the two rear lenses missing/cracked. The internal rear thread continues about 1/3 of the way down the barrel with an adjustable male threaded stop disc - so the barrel could be shortened. The front mounting ring, once the lens has been removed, could allow for mounting disc stops. Now we just need a special offer week from Edmonds!

Dr Klaus Schmitt
2-Dec-2009, 09:39
Well, yes, nice things can be found at their site, usually the first place where I have a look for optical stuff.

Struan Gray
2-Dec-2009, 13:33
Edmund are also one of the few optics houses who are truly happy to deal with private individuals. Their UK arm is nicely inside the EU, which simplifies shipping, VAT and customer care.

For tinkerers, it's always worth checking out their discounted items lists, and having a look at Anchor Optics (www.anchoroptics.com), their 'commercial' grade outlet. For example, right now there are some big condensor lenses with long focal lengths that would make fun swirly project lenses.

Klaus: do you know about the Visby lenses? If the vikings could grind quartz aspheres in the 11th century, it might be possible at home today :-)

Dr Klaus Schmitt
2-Dec-2009, 15:48
Yes Struan, Anchor is their "surplus" dept. much less expensive, but haven't found much there.

I know the famous Visby quarz aspheric lenses of course, a miracle indeed for the time they have been made.
I'm still in awe when I see amateur astronomers grind their fused silica mirror blanks!