PDA

View Full Version : JM Sharkey's Magical Mystery Macro lens.



Darin Cozine
18-Oct-2004, 15:03
JM Sharkey, an Epay seller who specializes in too-good-to-be-true advertizing, is at it again.

This time there is a wollensak 88mm f1.4 lens, obviously one of the oscilloscope lenses that sell dirt cheap. However in this case it is being sold as a 'macro' lens with "much more depth of field than ordinary lenses. " He claims it is "formulated like the infamous Cookie Deep Field Panchro"

Is there any truth to this claim?

I've also read most others say that oscilloscope lenses are very soft.

Dan Fromm
18-Oct-2004, 16:04
Darin, I don't know who's behind the name. For all we know, it could be a dog. In any case, there's no magic lens design that gets more DOF on film than any other, given magnification and aperture. The Deep Field Panchro is just a well-made carefully-calculated double gauss lens in the OPIC/Panchro/Planar/Xenotar/... family. I shoot a close relative, a 4"/2.0 Taylor Hobson Anastigmat; nice lens, doesn't work wonders.

IMO, JMS crosses the line between permissible hyperbole and, um, overstatement.

Cheers,

Dan

Kerry L. Thalmann
18-Oct-2004, 16:34
"Magical" qualities aside, it looks just like another old oscilloscope lens to me. In fact, if you supersize the first image you can clearly see the letters "OS" after the f1.4 engraving - likely the beginning of the name OSCILLO-RAPTAR or similar. I've seen countless similar lenses end up in the scrap heap at work over the last 15 years. Sometimes the shutters can be salvaged for use with other lenses, but the glass itself is pretty much worthless for anything other than the original intended purpose - recording images off an oscilliscope CRT onto Polaroid film. As such, they were not required to have very high resolution, or a very wide angle of coverage. Also, I've heard they are not flat field but have significant field curvature to match the face of the old fashioned CRTs they were intended to photograph. Most oscilloscopes made in the last 15 years have either a printer port or a floppy drive so images can be stored in a standard file format and viewed/printed on a PC. Thus, no more need for oscilliscope cameras. That's why so many of these lenses have ended up in the trash (or on eBay) in recent years.

If you need an Alphax shutter for some reason, go for it. Just don't be swayed into bidding too high by the "enthusiastic" description. If you really want an old oscilloscope lens and have a friend in the high tech industry, they could probably get you one for free out of the company dumpster. That's where most of them eventually end up.

Kerry

Ernest Purdum
18-Oct-2004, 16:40
Apparent depth of field does increase with softness, up to the point of the pinhole with which nothing is in focus but everything is equally sharp or equally fuzzy.



At f1.4, maybe his lens is soft enough to produce this effect. Does he also sell Florida real estate, or bridges in the Manhattan area?

Jim Galli
18-Oct-2004, 16:45
Yadda Yadda. I'm guilty of selling a few of these, but when I do I make sure that my buyers know that the lens was corrected for a curved field of an old fashioned 1950's crt screen a few inches away and that it is very probably good for nothing. People seem to buy them anyways. In fact the worse stuff you tell them the more excited they get.

Jason Greenberg Motamedi
18-Oct-2004, 16:53
As Ernest points out, the only way of increasing depth of field is by inducing astigmatism. So, soft focus lenses often have more apparent depth of field than "sharp" lenses because astigmatism has been purposely induced via spherical or chromatic aberration.

Kerry L. Thalmann
18-Oct-2004, 16:56
In fact the worse stuff you tell them the more excited they get.

Hey Jim,

Maybe they think a really crappy lens will make them the next Sally Mann. Of course, they overlook the fact that Ms. Mann has immense talent to go along with her crappy lenses.

Kerry

Jay Staton
15-Dec-2004, 10:31
There is a sucker born every minute. And I am that fool! I paid $442.77 for that "great" lens.
A lens that promises 2 stops more D.O.F. than the rest, how could I pass that up. I am not a physics major, unfortunately, so I was impressed with Mr. Sharkey's claims.

I haven't put the lens into a lens board yet, but based on the previous comments about the lens, maybe I won't waste my time.

Is there anyone interested in a nice paperweight?

Oh, by the way, I am from Florida, and am looking to sell some of the nice swamp land I bought 20 years ago.

Byer Beware!

Jay

cpellp
3-Oct-2006, 20:05
My Dad passed away about a year ago, and my Mom and I are liquidating their large-sih collection of cameras and accessories. We have one of these "heavy" lenses. I can take pics and send to anyone interested. Although perhaps not noteworthy, it may provide a for a source of interest to someone. If anyone interested, please let us know. Description around lens: Wollensak 31/2' (88MM) f/1.4 Oscillo-Raptar 1:1 No. E22986. Comes in a handmade circular handmade box. E-mail: cpellp@bellsouth.net

walter23
5-Oct-2006, 12:33
If you have the lens, you might as well try it out.


There is a sucker born every minute. And I am that fool! I paid $442.77 for that "great" lens.
A lens that promises 2 stops more D.O.F. than the rest, how could I pass that up. I am not a physics major, unfortunately, so I was impressed with Mr. Sharkey's claims.

I haven't put the lens into a lens board yet, but based on the previous comments about the lens, maybe I won't waste my time.

Is there anyone interested in a nice paperweight?

Oh, by the way, I am from Florida, and am looking to sell some of the nice swamp land I bought 20 years ago.

Byer Beware!

Jay

Capocheny
5-Oct-2006, 13:00
Darin,

As they say, "Sometimes gold, sometimes pyrite!:)"

Cheers

Void
30-May-2008, 06:27
If you need an Alphax shutter for some reason, go for it. Just don't be swayed into bidding too high by the "enthusiastic" description. If you really want an old oscilloscope lens and have a friend in the high tech industry, they could probably get you one for free out of the company dumpster.
Kerry
What size of Alphax is it?