4 Corner Adjustment - Linearity Distortion

I’ve only ever used it with internal content, and I can tell you it doesn’t automatically project from any angle.

Mine was perfectly square on the startup screen but when I try and play something through a firestick its badly distorted.

The design intent is that the projector should adjust automatically when it is angled up or down. The automatic procedure is only designed to handle projecting against a vertical wall or flat ceiling, and must first be calibrated against gravity in a neutral position to know what “down” is. An internal sensor can then sense the angular difference between what was calibrated, and the current direction of gravity.

The projector lacks sensor capability to determine its own horizontal angle against the screen (left to right). From the projector’s own point of view, the picture covers the same angle even if part of the screen it is projected on is closer or further back.

I think it could be theoretically possible to program an appromixation of a “left-to-right” sensor by checking the difference in focus distance while adjusting to find focus, as the left and right side of the screen become sharp at different times. It would not be easy though, if the motorized focus is as imprecise as has been suggested, and the difference in distance is small enough that most of the screen looks “acceptably sharp”. It would probably yield a much less useful result than manual four-corner correction.

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13 posts were split to a new topic: Discussion about PPX features that were advertised but not present in final product

New PPM owner here.

I’ve set it up yesterday in our bedroom, on bedside table. It’s projecting at cca 30 degrees angle to the wall in front. It’s also projecting up. So in summary “right and up”.

I’ve manually adjusted 4 corners to the best of my abilities. Doing it manually is not too big of a deal for me however …

I have tried Netflix and H Linearity problem is visible - objects on the left are “squashed” and to the right larger then they should be.

I’ve read number of posts in this forum but I can’t figure out what is the latest on this problem. Is there an ETA for a solution (and I surely hope one is coming sooner rather then later)?

Welcome on board and thanks for your feedback!

Philips Projection is/was definitely working on this Task #29 and the Feature & Bug List [1] will be updated very soon. As far as I can see in the moderator section, the Task was marked internally as closed, so lets cross fingers for a software update announcement in the next time :wink:

[1] Current Bug / Planned Features list

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Thanks for the pointer to the backlog.

Items #16 and #29 are of interest. Not 100% sure what #16 is all about but #29 looks like it might be addressing the issue I am seeing. I hope we’ll get target version for this item soon.

Any progress on this issue? just wondering if this is targeted for an update release? 1.2.0?

Thank you!

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@Philips_Support_P When is the next SW update planned and would it include linear distortion fix?

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@Philips_Support_P is it possible to do horizontal auto keystone correction by using the onboard camera to recognise horizontal features in a room?

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Any update on the progress?

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I have had the same issue as most in here (not a square image) and I just thought it was “normal” but I have now received my second pico today (bought one for my parents) and it does not have this issue. I believe it is a manufacturing defect in the original unit as no matter the surface the pico is projecting on, it never produces a square image - always a trapezium. The focusing is also far louder in the original.

Please tell me what comparison pics you would like me to upload to further demonstrate the issue.

Someone from Screeneo really should make clear if it’s factory issue and reason for replacement or it’s fixable by FW. I’m also facing this issue and I thought it’s normal and I’m not happy with it

All of them! Well, those you consider showing enough to display the difference between the two devices would be really helpful.

The issue that this thread is addressing is not about correct rectangular projection, this is about linearity distortion that happens even if you manually adjust the image correctly with 4-corner adjustment.
The image does not compensate for the angle the projector is at relative to the projection and distorts the image (one side stretched, the other compressed).
Your issue sounds different and there are threads of users mentioning that issue.

That’s the distorsion we are talking about. Am I understanding correctly that’s an hardware issue? Size of icons is almost doble from left to right.

I don’t think this is a hardware issue. The 4 corner correction is purely done in software unlike the vertical keystone correction. Hopefully, this one will be fixed soon. 4 corner correction right now is almost like an anti-feature because it’s not working properly and takes a lot from the system performance.

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Yes you are correct. That is different to my issue -

Red = Original Pico
Yellow = 2nd Pico
Black = Rectangle

Unless you created a bracket to hold the PPX in the exact same position, which you have securely mounted at the same spot, for both sets of pictures, you can’t compare these pictures. Any offset from the lens plane being perpendicular to the wall will create a distorted non-rectangular picture.

Any progress on the linearity distortion with 4 corner correction?? (not the rectangular image issue some people started talking about)

Any ETA?