Hello
i have been watching some projects and i notice some ppl put cold mirrors after the lcd pointed to the objective. Now my question is.. a cold mirror i guess it's to prevent high temperatures.. if this is used after the lcd the lcd will stay with high temperatures.. so whats the point of use a cold mirror instead of a "normal" mirror?
Can anyone explain this to me please?
in case that i do a projector with direct light like this: light>fresnel>lcd>fresnel>obecjtive. it's work put a temperated glass between the light and the fresnel? will it help me anyway keeping my lcd cold?
...Obvious i'll use fans too
Thanks 🙂
i have been watching some projects and i notice some ppl put cold mirrors after the lcd pointed to the objective. Now my question is.. a cold mirror i guess it's to prevent high temperatures.. if this is used after the lcd the lcd will stay with high temperatures.. so whats the point of use a cold mirror instead of a "normal" mirror?
Can anyone explain this to me please?
in case that i do a projector with direct light like this: light>fresnel>lcd>fresnel>obecjtive. it's work put a temperated glass between the light and the fresnel? will it help me anyway keeping my lcd cold?
...Obvious i'll use fans too
Thanks 🙂
i think that they do use regular mirrors. but i could be wrong. and i think it gives longer focal length.
your setup is wrong. you need two fresnels or a ohp fresnel
light---ohp fresnel---lcd---objective
or
light---fresnel---lcd---fresnel---objective
your setup is wrong. you need two fresnels or a ohp fresnel
light---ohp fresnel---lcd---objective
or
light---fresnel---lcd---fresnel---objective
eheh no problem
about the mirror again.. i guess i'll try to use a "normal" mirror as long as it will be after the lcd there is no problem with temperature.
i did some tests with a small mirror that i had from one comercial projector and it was well focused except the edges but that's probably because it was a really small mirror.
about the mirror again.. i guess i'll try to use a "normal" mirror as long as it will be after the lcd there is no problem with temperature.
i did some tests with a small mirror that i had from one comercial projector and it was well focused except the edges but that's probably because it was a really small mirror.
What you want is a simple, relatively cheap Front Surface Mirror. It doesn't have all the refractive/reflective losses inherent in having another pane of glass in the signal path.
They most definitely aren't using cold mirrors after the LCD, btw. Cold mirrors are prohibitively expensive for most of the people on here for fullsize projects. There's ONE source I've found for cheap dichroic cold mirrors, and they're 5" to a side. Not very viable for a 15" LCD.
Other than that, I've found a single store with a small spherical cold reflector for a moderate amount of money, and the numerous manufacturers who will make you a one-off for hundreds of dollars.
Lumenlabs will hopefully have an ETA on their condensor / cold spherical reflector setup soon.
They most definitely aren't using cold mirrors after the LCD, btw. Cold mirrors are prohibitively expensive for most of the people on here for fullsize projects. There's ONE source I've found for cheap dichroic cold mirrors, and they're 5" to a side. Not very viable for a 15" LCD.
Other than that, I've found a single store with a small spherical cold reflector for a moderate amount of money, and the numerous manufacturers who will make you a one-off for hundreds of dollars.
Lumenlabs will hopefully have an ETA on their condensor / cold spherical reflector setup soon.
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