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Curve projector display

1727 Views 27 Replies 5 Participants Last post by  Y.K.A
I deleted the question. Sorry. I had a basic misunderstanding. My question is irrelevant to others so I deleted.
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Hello everyone. Apologies in advance for the English I use Google Dictionary. I bought a dlp projector for close to $ 1,000. I have a particular interest that I think is a problem and I wanted to consult with you. In the meantime I prefer not to expose the brand itself because I do not want to give it a bad name. The projector has an automatic shape correction and there is a manual correction of 4 corners. The automatic repair only works when the projector is placed on a table (i.e. not hanging upside down) and it does not align well. When the projector is hung from the ceiling it is hung upside down and this function does not work at all. The manual repair works. The problem is that when the projector is placed or hung upright and balanced, the screen height is not the same on both sides. On one side I measured 119 cm, while on the other side the height is 116. The points of shape correction are all set out to the end. My question is is it ok that the image is not straight in the default mode. That is, the correction is intended to align the shape when the projector is not positioned straight, and should not compensate for the image not being straight in normal mode. Seemingly this is not a problem, I can slightly reduce one side in a manual correction, the problem in this situation is that when there is a dark image, the curved shape is the one shown. This is because even when I narrow the view, there is still some light flowing in the original original form, which as mentioned is the one that is crooked. The seller does not really understand the problem. I checked pictures of other projectors and saw that it was supposed to be straight. What do you think about this situation?
It would help to know the projector model. You should not be using keystone correction, but instead level the projector and ensure that the top edge of the image is centred on the projector lens and is the correct height for the projector's image offset.

This is an example using a UHD35:

According to the calculator (and Optoma's specifications) the top edge of the image should be about 6cm (5% of image height) below the centre of the lens, when ceiling mounted.
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It needs to be looking down more

If your image is trapezoidal like this \---/
Rotate it forward and you should see |---|
Rotate too far forward and you'll see /---\
Thanks for the comment friends. My projector is not on this list. It's a Chinese projector. Is a relatively new but high quality brand. However, this is not a problem of how to position the projector or how to set it to see a straight image. Two other problems - the first is that when the projector is placed balanced, and the manual correction is directed outwards to the maximum extent, the screen is asymmetrical. And the second problem is that with manual or automatic repair still light leaks in the curve form.
Weird. Sounds like you're beyond the focal plane or have the projector making too large of an image maybe.
Like Dun said you'll need the model and to do a throw calc to get more info.
הוספת תמונות עוזרת באבחון. לפעמים אפילו רמה מושלמת עדיין לא מדויקת
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Ok so part of what you have is "קצה מאיר"
We call it "light border" but that would be the best way to describe it.

האם מדובר על יחידות מציאה לתופעות לוואי. מקור ההקרנה אינו מעומעם מספיק
יכול להיות שיש 1.5-3.0 ס"מ ממנו. לא כל כך

בעיה נוספת היא כיצד המרכז משמאל לימין נמדד מהמקרן. הקירות בחדר, האם המדידות הן מרחק שווה?
ש גם דבר שנקרא "קיזוז אנכי"

יהיה עליכם לשקול זאת

בהתקנת המקרן שלי, למשל, אני מקבל מסך בגודל 135 אינץ ', אך התמונה צפויה לנוע למטה 18 ס"מ ממרחק של 4.5 מטר.

אם אני מיישר את המקרן כך שחלקו העליון של המסך יהיה זהה למקרן, הוא למעשה לא מפלס!


אם זה מחושב ברמה מכאן ועדיין תוצאות רעות, הייתי חוזר ליצרן
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Friend, thanks for your response. I'm not sure I understood what I needed to check about what you said. If I look at a simple thing - the projector is balanced, the walls are straight, if the space between the display and the ceiling is the same on both sides, then even down it should be balanced, right?

אפילו כמות הנפילה מהתקרה צריכה להיות מאוזנת בהתאם למפרט היצרן
Sounds like the projector is not square to the screen, or the screen itself is not flat and square.
It is projected on a wall that is completely straight.
But the projector itself isn't perfectly perpendicular. I think everyone understands you're saying it's "balanced" but the image it's shooting says it's not.

Loosen up the mount and play with the angle. Tilt it slightly up and slightly down and see how the image changes, from wider at the top to wider at the bottom. You should be able to manipulate it to have the sides be perfectly parallel.

Now if your projector has no lens shift, then it has to be a specific distance from the ceiling and perfectly perpendicular with the screen to get the image where and how you want it.

It can be a pain in the butt trying to square the projector. And while using the Keystone correction isn't ideal, if you care more about a perfect rectangle, then maybe move the projector back a little more. The image will be slightly bigger and you can use less 4 corner correction to square it.

Honestly I think people blow the use of Keystone out of proportion. Peace of mind and actually enjoying watching a movie is more important than the slight degradation of the image. But that's just me.

Sent from my SM-N981U using Tapatalk
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