General Table for Projector/distance/Psd resolution/wall

maxiwille

Hi All !! maybe is a question that could be no precise, but i will try.... What I want to know if there is a way to calculate the relation between Resolution of an image/Psd file, the distance from the Projector to the wall, and the wall´s size? For example a 10x5 mts wall a projector 10 mts away from the wall. what could be the the correct resolution for the Hd image ?

Best,

Maxi

Michel

@maxiwille

If your projector has a resolution of 1920x1080 it does not make sense if you pictures resolution is higher than that.

Best Michel

maxiwille

Thanks Michel ! I understand. But considering this: a 10x5 mts wall surface, a projector 10 mts away from the wall with the projector you mention, will be the image pixelated ? Thats where my confuses questions aim.

mark

@maxiwille,

Well, the size of the pixels will be image size [ 10m x 5m ] divided by projector resolution [ 1920 x 1080 ] = 0.52cm x 0.46cm. The distance between the projector and the wall doesn't enter into the calculation, since you know the resulting image size and resolution.

Best,

Mark

MatthewH

Whether something will appear pixelated has as much to do with distance between the viewer(s) and the image surface as it does to do with the size/pitch of the pixels. A 10mm LED video wall which has a full centimeter between pixels does not appear pixelated from far away. Conversely, a 1920x1080 laptop monitor can appear pixelated if your face is close enough to it. The type of content you intend to display also greatly impacts perceived quality in this regard as does the type of projection technology. For example, unlike DLP and LCD projectors, LCOS projectors do not have lines between their pixels which can help them to appear less pixellated even with the same number of pixels per cm and viewing distance. Conversely, LED tiles have large black spaces between each LED SMD which makes them generally appear more pixelated. There really is no simple mathematical calculation to answer this question for you. You can easily do the pixels per measurement calculation that mark indicated but you will just have to develop a sense for what that number will mean in practice with different types of venues, display technologies, content, etc to know whether or not it will be a suitable resolution for a given application.

maxiwille

Thank you all !! Its very clear what you all say, also that projectors and projecting are a whole world, and must say that I feel prety ignorant Best Maxi

Clement

Hi there !

A calculation exists to predict the minimum distance to not see the pixels (doesn't work with LED walls as mentioned by Matthew Haber).

The separative power of the eye isn't able to differentiate two points separated by 1mm if the spectator is further than 3m.

So, in Mark's example, with a 10m wall base and a 1920x1080 projector, the pixels are more or less 5mm : to not see pixels, spectator has to be distant of 5 x 3 = 15m.

I didn't test this method yet, but it's good to know anyway.

All the best !

maxiwille

Thanks a lot Clement !!

Best

Maxi

Woland

I know that in this particular case it might not be useful, but in questions involving projection throw this projection throw calculator has served me well in the past.

Cheers,

Woland