Although, to answer your real question, many theaters are cheap, plain and simple. I don't mean to be sarcastic, but that's usually the reason. Many times the public will accept lower quality if they don't know better, or there no other theater close by.

In addition to focus, different lamps, lenses, screen types will change the color temptature, requiring a 3-color temp meter (very expensive, $20,000 last time I looked.)

There are some places that do care, but it takes money, and theaters have always been a 'feast-or-famine biz' kind of biz.

I do feel that printing a simple version of a test/alignment film onto the heads or tails (just like the "color-test-girl") would be very beneficial, but no one liked my idea when I suggested it awhile ago (sniff-sniff!) I did make a proposed pattern, if anyone wants to see it.

I am not suggesting that a full blown projector test image be printed on the head of the film. I was just thinking of a simple focus test and maybe a lens test.

In the machinist world you have "go" and "no go" gauges. I am sure the resolution of the print film would support a diffraction pattern that would spell out "go" in focus and "no go" in a defocus condition.

Just a thought.

I am using a Kollomorgen BX241 3.75 inch lens in my system. The same lens listed in the beginning of the post. I am also using a Kollomorgen-ISCO KA298 Anamorphic. Both together have been opticl bench tested at about 125 l/mm at 15 ft. Not bad for an old system and at 15 ft.

I should retest it. At the time only interested in how close I could get the anamorphic to focus and not it's maximum resolution.

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Actually, I did get to 12.5 ft before resolution fell off a cliff. I didn't check it the other way. I am sure these lenses are distance dependent and have a peak resolution distance.

The Kollmorgen ISCO KA 298 German made anamorphic was pulled out of a newer bankrupt theater. It does say ISCO on it. Does anyone know the history on this optic?
It looks to me that Kollmorgen and ISCO at least had one lens in common.

I do think that a simple focus test or maybe a Phase Contrast target using the words "go" and "no go" could be done. It would not take any more technology then the digital sound timing data located on the edge of the film.

It would be more or less using a Moire pattern to check focus and lens quality. I guess I am sort of into Moire patterns. They are kind of fun to play around with.

I notice that several people on the net have the newer ISCO MC lenses for sale for about $200 each. I would like to get down to about 3 inches focal length. I just might buy one of these.

Larry

Also, you can use them to read the fine print on perscription bottles! (Us old foggies need that....)

You can easily see that steel sliver you ran into your thumb so you can yank it out with a wire cutter, blah blah blah..., and if you are not well-endowed, they can be very handy in the restroom. (Ahem)

Now I too have issues with 35-PA not being nearly consistant enough.

Steve

The problem is that it isn't representative of the typical frame...it is too black. Sure it will put the optical system through it's paces and give you more information than 35-PA in some respects, but isn't as good in others.

One of the nice features with it is the grid lines to see geometric distortions caused by the lens and keystone. (SMPTE used to produce a film called 35-FA that had a better grid and was more of a neutral gray).

On your Magnacom tests...have you tried different vintages? For instance, ISCO has two different versions now (Type S and Type-L) that replaced the older Magna-com 65. Schneider still has theirs. Then there are the old Kollmorgan Magna Coms.

A current magnacom or Ulta-Star Zoom Converter (as they are now called) can be a dynamite lens in the proper application.

Steve

As I said before, in the right application, Magna-Coms can be wonderful. Take, for instance, projecting onto a Cinerama Curve screen...what distortion? The picture will start to square up more so than with a conventional lens...sure the sides will pincushion a bit but this is less noticable than the barrel distortion of a conventional lens on horizon lines. In fact, the Zoom Converters are nice on curved screens in general where the radius is less than throw.

As to Schneider's Variable Primes...The claim is that they offer a varible focal length without any of the downfalls of traditional zoom attachments. In fact, Dwight wanted to have the front of the lens say something to the effect of " not a zoom, not a magnacom!" Hence the "variable prime" designator to make it sound somewhat better. Personally, I think they are just too expensive for what they offer, that is the bare minimum of cropping. Now that Schneider and ISCO offer the shorter focal lengths in 2.5mm increments, what is the point? The fringe area caused by the aperture plate spacing from the film plane has a greater effect than the 1mm of focal length difference!

Well those are my opinions and observations.

Steve

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion