Someone will remeber the lamp problem that I had in one theater with lamp alignment and power (4000W at 105A). At that time I posted the following picture to explain how the lamphouse has been aligned.

Now, the lamp has been replaced with a 3k one. I went to the theater with my colleague to check the cinemeccanica's alignment and I found the following problems:

1. The "focus" leverage on the lamphouse is at the end of its range. I have a good uniformity on the screen but I think that can be better
2. The vertical alignement works only in one way; I cannot align the lamp way up.

I believe that the adapter installed on the 3k to match the 4k plug has move too far the lamp itself. What can I do without the "help" of Cinemeccanica?? The problem the photo is explaining is still there...
The projector is a Vic5 in a consolle.

More: the screen is very big (15meters, 49.21 feet) and too near the projector (I think no more than 68 feet, 21 meters).
The geometry of Cinemascope is very bad. I tried to rise the frame up and down to see the frameline: they appeares like this draw:

Lenses are made by ISCO (I'll check the model).

What can I do to increase the picture quality???

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What about the geometry issue?

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Noone answered to my geometry problem.

Since I'm facing the problem with my manager, I would like to have your opinions!
Let me update to the situation.

That theater definitely has the lamp/lamphouse/lenses in a very very bad alignement.
I hope that my manager provide me a laser alignement to correct it, I now have few feet of 35PA to check the scope but...

Yesterday night I was at that theater to see "collateral damage" that is in 1.85:1.
Before the show I saw the trailer of "Killing me soflty" that, in Italy, has few black words on a white background.
I have that trailer at my cinema too and I always saw that words fucosed perfectly. Yesterday night I saw that words out of focus but, better, with a strange "halo" surrounding them. It was just for few moments but perhaps I saw a red halo surrounding the words...
I went under my screen (since in that theater the screen is very big and the room is not so long...) and I confirmed that the words are perfectly focused.

I also noted that the geometry problem is still there also in 1.85:1 (not so viewable as in 2.39).

So my questions are:

1. Can be the lamp/lamphouse/projector/lenses alignement affect the quality of the image or just the quality of the light?
2. WHY that lenses are deforming the images?????? The screen is completely FLAT, but the projector is not in the absolute center of it, is slighty shifted, not too much. Lenses are made by ISCO.

I will try to remove the booth/auditorium glass since I believe that it is not a quality glass. Parhaps that is the problem.

In the meantime I will appreciate any suggestions!

Lens design is a science, and I wish we had a film-tech member who was involved in this. I'll give you my take on the subject, but if I am wrong I'll be happily corrected by a qualified representative from one of the lens companies.

What you are seeing is called pincushion distortion. The opposite type of distortion where lines curve outward is barrel distortion.

If the film in the projector was perfectly flat and the screen was perfectly flat, and the audience sat exactly in the "sweet spot," this would be an inexcusable flaw in the lens design. However, a projector lens has to be designed for a curved field, because the film in the gate isn't flat, but warped by heat (except in projectors like the Imax projectors.) Even worse, the lens designer can't be sure exactly how much the film will curve in the gate. Generally, the hotter the film, the more it curves. That means the lens designer must make compromises and assume certain things, like the film distortion caused by the most common lamp (2,000 watts), most common shutter, average humidity, average size of image in the aperture, and an average density of the film. In short, a good projecter lens is very specialized and must be much different than a good camera lens.

When an audience must sit too close to a screen, a little pincushion effect in the lens can be a good thing. It has the visual effect of compensating for the barrel distortion of the image caused by sitting too close to the screen. Certainly it is less noticable than barrel distortion, which can have the effect of seeing the image projected on a barrel or big ball. The amount of distortion you have drawn seems excessive. If the distortion is this much, it could be a design flaw in the lens.

The halo around the credits is called chromatic abberation, which simply means that all the colors don't focus in exactly the same spot. A perfect lens doesn't have it, but as I've said, projector lenses are not perfect, but compromises. Sometime chromatic abberation gets worse as a lens ages and coatings are lost or damaged from heat and light. (Oddly, I've been told that on the earliest camera lenses, chromatic aberration often diminished with age as pollution made a coating on the lenses.)

It sounds as though you might have lens problems, and it might be worthwhile to try some other lenses to compare.

I do not completely agree with you...

1. Geometry distortion: aperture plates on that projector has been worked to compensate the distortion on the screen (its shape is bended). Why my aperture plates, at my theater, are perfectly straight and boders on the screen are not bended? If you have a flat screen, I'd say that the projector would project the images straigh, not bended... let's suppose that the projector is not at the center of the screen: an hypotetic cube on the screen will became a trapezium, but not a sphere!!!
The amount of distortion I've drawed is real, I'm not exagerating.
I will try another lens, but I'm afraid that my lenses will make a too small picture on that screen to evaluate it.
2. Chromatic aberration: how many years can a lens be used without problems? Mine is in service since 8 years with no visible problems. That lenses are in service since 4 years but with bigger lamp (4k and now 3k, mine has a 2,5k).
3. Focus at credits: good tip, I never tought about that!

Greg,
Yes, I'll try another lens. Align-o-tron: I'm not the one that pay for these stuff, once my manager will be convinced about the usefulness of that tool, I will can align the lamp in the best way!

Bye
Antonio

I have a hard time agreeing with myself sometimes. As, I said, it would be nice if a lens designer could set the record straight. I imagine many of the techs here know more about lenses than me. I just have a big mouth and like to use up Brad's bandwidth.

"1. Geometry distortion: aperture plates on that projector has been worked to compensate the distortion on the screen (its shape is bended)."

Most of the plates I've seen have minor distortions in them. I heard that Bob Maar cut one to look like a martini glass.

" Why my aperture plates, at my theater, are perfectly straight and borders on the screen are not bended? "

Probably you have a better lens.

"If you have a flat screen, I'd say that the projector would project the images straight, not bended... let's suppose that the projector is not at the center of the screen: an hypothetic cube on the screen will became a trapezium (trapazoid), but not a sphere!!!"

True. Here is what I mean by barrel distortion A square projected on the screen looks like it is projected on the bulge of a sphere.

"The amount of distortion I've drawed is real, I'm not exagerating.
I will try another lens, but I'm afraid that my lenses will make a too small picture on that screen to evaluate it."

I think you will see a noticable lack of distortion with a different lens.

"2. Chromatic aberration: how many years can a lens be used without problems? Mine is in service since 8 years with no visible problems. That lenses are in service since 4 years but with bigger lamp (4k and now 3k, mine has a 2,5k)."

I don't know. I've seen new lenses ruined by running a projector without any film in the gate. The current crop of lenses may not be affected as much. If different glass is used to get the same effect as a coating, it may not be damaged as much by overheating or age. You are getting beyond what I know.

Probably you have a better lens.
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Same lenses. ISCO ones, blu series.
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"If you have a flat screen, I'd say that the projector would project the images straight, not bended... let's suppose that the projector is not at the center of the screen: an hypothetic cube on the screen will became a trapezium (trapazoid), but not a sphere!!!"

True. Here is what I mean by barrel distortion A square projected on the screen looks like it is projected on the bulge of a sphere.
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I have nothing of that at my theater. Since projector are tilted and higher than the screen I have the aperture plate borders on the screen forming a trapezium, but are absolutely straight!!!
Do you think that a lens with minor focal can have the barrel distortion?

Bye
Antonio

"Do you think that a lens with minor focal can have the barrel distortion?"

The screen is 15 meters wide and the projector is 21 meters far.

I don't have right here a converter...