Heya teletag, i had a scope for a while and had a look around for a good while in the skies of Australia, i had a tasco galaxsee 675. Not a bad scope, but nothing compared to a newtonian, ive always wanted to build one of these and may do in the future, but time is always the issue with me latley lol
You are dead right about how we can relate a scope's optics to a projectors light engine, its what you say, its a scope in reverse, and its prety much how i started out in learning about light engines in the beginning. Just smaller focals is what we work with and somtimes a few different reflectors.
Trev
You are dead right about how we can relate a scope's optics to a projectors light engine, its what you say, its a scope in reverse, and its prety much how i started out in learning about light engines in the beginning. Just smaller focals is what we work with and somtimes a few different reflectors.
Trev
Lol
Well I'm working on projector Mk2.
I have been sucsessful in projecting around 2m wide 16:9
But my light source is a 150watt OHP
I'm hoping to get a 250+ MH system up and running
but suppliers in the UK are hard to find for the LCD etc.
Funny you should mention about making a telescope.
Thats exactly what I'm doing right now.
I'm hoping to get a robotic scope up and running in around 2 years. Take a look at my site at http://www.teleteq.mine.nu for
my project details (Still under construction
)
Sorry of the thread hijack
Well I'm working on projector Mk2.
I have been sucsessful in projecting around 2m wide 16:9
But my light source is a 150watt OHP
I'm hoping to get a 250+ MH system up and running
but suppliers in the UK are hard to find for the LCD etc.
Funny you should mention about making a telescope.
Thats exactly what I'm doing right now.
I'm hoping to get a robotic scope up and running in around 2 years. Take a look at my site at http://www.teleteq.mine.nu for
my project details (Still under construction
)Sorry of the thread hijack
teletag
Nice
I started to make a robotic tracking satelite dish as i got into downloading live images from space from various satelites before i left Aust, its not very common but its around on the net. Ive got satellite tracking programs and a skywatch program with tracking software for a elqualatoral robotic tracking system if your interested. You just need to make a plc card for the comp and get a hold of 2 ham radio antenna rotators for the motorised mount. use this with the software and you can track anything in space lol.
As for the thread jacking yeah we better call it quits, email might be the go, all the best in your projects anyway.
Trev
Nice
I started to make a robotic tracking satelite dish as i got into downloading live images from space from various satelites before i left Aust, its not very common but its around on the net. Ive got satellite tracking programs and a skywatch program with tracking software for a elqualatoral robotic tracking system if your interested. You just need to make a plc card for the comp and get a hold of 2 ham radio antenna rotators for the motorised mount. use this with the software and you can track anything in space lol.
As for the thread jacking yeah we better call it quits, email might be the go, all the best in your projects anyway.
Trev
I agree that the parobolic reflectors are best for parallel light raws and that is nothing new, BUT there are alot light we can´t use with the parabolic reflector, there for is the elepticalreflector a better choise because we can collect more light with it and yes the rays may not be completly parallel but that is not a problem, the condensorlenses correct this.
And the above picture is eliptical, is´t not bend in anyway it´s the reflection that make it look like that, this is still true if you look at the picture i took of my reflector you can see that you get strange reflections, the blacklines you see are reflections from the metalbox take another look !
And the above picture is eliptical, is´t not bend in anyway it´s the reflection that make it look like that, this is still true if you look at the picture i took of my reflector you can see that you get strange reflections, the blacklines you see are reflections from the metalbox take another look !
The image in the post quoted below is incorrect optics btw. If you look at the two pairs of rays furthest to the right, their incident angles of reflection do NOT match their reflected angles. THe incident angles look about 20+deg where their reflected angles are more like <5deg.
Err well this post jumped a page, so look one back to see the image I'm talking about. Here's a link to the post: http://www.diyaudio.com/forums/showthread.php?postid=338347#post338347
mathias said:
Err well this post jumped a page, so look one back to see the image I'm talking about. Here's a link to the post: http://www.diyaudio.com/forums/showthread.php?postid=338347#post338347
mathias, ive been working with steel for the most part of my life, i am also a certified engineer in metal, i also have very good eyes, and im telling you its a bend. Buy one of these and prove us that im wrong because i can garentee you that its a bend. That reflector is a cheap press formed steal reflector and ends at the bend, the rest is the light guide to not waste light, nor to contaminate surounding areas, and to stop light comming out of other areas. This is just press formed into a one peice unit.
Trev
Trev
LOL the eliptical reflector concentrates all light gatherd to a secondary focal point, normal torch lights use parabolic, u can even test this with your finger. Dont go on shape mathias as parabolic reflectors come in manny shapes and sizes depending on their beam spread and are normally not drawn as a half circle either like you have ilistrated in your drawings, they have a slight PART of an elipse, but once again this depends on the aplication and the desiered amount of light to be reflected, also not all parabolic reflecters are used to reflect perfectly parabolic rays, some alpications like a torch have the beam spread slightly out. Buy a magna light if you want to see what a lens does to a torch and ajust the beam angle.
Trev
No they don´t, a parabolic reflector is not so deep.
A parabolic reflector can not have any other scape than parabolic, if it´s deeper than a parabolic, it´s a elipticalreflector. If they use a mix of parabolic and eliptical in a torchlight I don´t know, but it´s alot deeper than a true parabolic. And this deep shape is what I am talking about. This deep parabolic collect more light than a true parabolic-reflector.
It´s pointless to argue about the picture, I say it´s not bend, and you say it´s bend, let them how watch the picture self decide.
Anyway I have proved with my own picture from a torchlight that the reflector has a shape more like a ellipse.
mathias put a peice of paper infront of the torches reflector, without its lens on and see what pattern u get on the paper with the paper standing on its end. Its parabolic.
As ive said you can also test this with your finger.
In the picture below these are all parabolic reflectors, the one on the left and center is a 25deg spot light, the one on the far right is a torch reflector, they are all the same shape and are parabolic.
And mathias im not arguing im stateing facts.
As ive said you can also test this with your finger.
In the picture below these are all parabolic reflectors, the one on the left and center is a 25deg spot light, the one on the far right is a torch reflector, they are all the same shape and are parabolic.
And mathias im not arguing im stateing facts.
Attachments
Guys,
The fact of the matter is that there are differing shapes of both parabolics and elliptical reflectors. Both kinds can be made shallow or deep. The difference is that they follow a different mathmatical formula for how the slope of the curve changes. It is possible to make an elliptical reflector that is so close in shape to a similar parabolic that it would be hard to tell at a casual glance which is which. You would have to have them superimposed on each other to tell the difference.
Hezz
The fact of the matter is that there are differing shapes of both parabolics and elliptical reflectors. Both kinds can be made shallow or deep. The difference is that they follow a different mathmatical formula for how the slope of the curve changes. It is possible to make an elliptical reflector that is so close in shape to a similar parabolic that it would be hard to tell at a casual glance which is which. You would have to have them superimposed on each other to tell the difference.
Hezz
Hezz ive just tested my torch out, its parabolic for sure, all of the other parabolics that i have and are known parabolics share the same shape, and thats why i have taken the pictures and posted them up, your right about the depth factor and this is normally used in area size and focal lengthes given to a certian the aplication can fit into, it also has alot to do with eficientcy.
Trev
Trev
mathias i dont understad you somtimes, these are parabolic reflectors, not eliptical and no way can they work in the same way, sure they will come close, but its ineficient and they arent designed to do so, if they did well then they wouldnt have made a parabolic reflector and a eliptical would they? Its imposible to turn a parabolic reflector into an eliptical. However you can turn a spherical to radiate parabolic light rays, but its not eficient and thats why we have a parabolic reflector with its acociated shape designed to work in an eficient manner.
Trev
Trev
Trev you must agree that the ellipse is closer in my torchreflector picture than the circle even if it´half round, that´s why I called this kind of reflectors elliptical, but as Hezz say it´s very hard to see the diffrence. Anyway it´s good that we are talking about the same type of reflectors, I would maybe called it "deep parabolic reflectors".
Yeah somthing like that lol, hey i just tried a parabolic with a condenser, no go , you will end up with a dark patch in the middle, i turned the condenser around the oposite direction also and basically you will loose light so a pcx on a parabolic is a no no and its why they arent comonly used at all on parabolics, this is where an eliptical has another advantage cos with an eliptical we can use a condenser of this nature because it has a focal point. In magna lights i think they use a double convex lens so its probally more the go on a parabolic system.
Trev
Trev
I just want to show the difference between a real parabolic reflector and a elictical/parabolic reflector. The reflector to the right is a true and orignal parabolic reflector, to the left the deep parabolic or eliptical reflector or what you want to call it. In my design where I say eliptical I mean the deep parabolicreflector. This is the type of reflector you must use in the slideprojector design.
If you want to build the slideprojector design, which is the absolute best design use condensors from a slideprojector and turn them in the way they are in the slide-pj. You maybe need bigger slideprojectorcondensors but they must have the same scape as the orginal slideprojector condensors.
Also with slideprojector I mean whose how use a ELC A1/259 multimirror bulb 150-250W.
If you want to build the slideprojector design, which is the absolute best design use condensors from a slideprojector and turn them in the way they are in the slide-pj. You maybe need bigger slideprojectorcondensors but they must have the same scape as the orginal slideprojector condensors.
Also with slideprojector I mean whose how use a ELC A1/259 multimirror bulb 150-250W.
Attachments
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.