Mirror question

Have been thinking about the visuals for my single seat 737. Came across these discussions here. Interesting & daunting. Seen a lot of talk about Mylar. But wondered why nobody seems to have a look at highly polished metal sheets or acrylic mirrors. Too heavy, too expensive or not good enough??Best regards,JWS

Mylar is really only the practical choice for making the mirror cell of a collimated display. g.

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Originally Posted by geneb

Mylar is really only the practical choice for making the mirror cell of a collimated display. g.

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Thanks for your response. Could you elaborate a bit on the 'practicallity' of that choice? I've seen how some people have managed to build a Mylar mirror, but to be honest, it seems to me a very demanding project, that involves lot's of calculations, correctly shaped woodwork or metal frame, vacuumcleaners, airflow regulation, etc. It seems to me that e.g. a polished metal mirror could be easier to handle (if not too big or too heavy), but then again I might be overlooking other problems. At least it is first surface by design.Best regards,JWS

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Originally Posted by JWS

Thanks for your response. Could you elaborate a bit on the 'practicallity' of that choice? I've seen how some people have managed to build a Mylar mirror, but to be honest, it seems to me a very demanding project, that involves lot's of calculations, correctly shaped woodwork or metal frame, vacuumcleaners, airflow regulation, etc. It seems to me that e.g. a polished metal mirror could be easier to handle (if not too big or too heavy), but then again I might be overlooking other problems. At least it is first surface by design.Best regards,JWS

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When correctly used, silvered Mylar will create an optically perfect*, seamless, spherical section mirror. This is why all commercial full flight simulators use Mylar for their mirror cells. Bending a sheet of metal into a spherical section would likely involve some kind of custom made press at an astronomical cost. I also doubt it could be polished even "good enough". * A Mylar spherical section mirror created by a vacuum is as literally perfect a mirror as you can create without going to a multi-ton glass mirror. You can either build multiple single-channel Wide Angle Collimators, or you can build a mirror cell & screen combination using vacuum drawn Mylar. Trying to use other materials simply isn't practical. It's either not good enough (metal) or too expensive (metal or glass). g.

Thanks for your further explanation.BRJWS