Cruser,
I sent the files to your e-mail address. The three attachments where about 1.6 MB so I hope your hotmail will take them.
I'm hoping to find two themoset optical plastics of the right refractive index and Abbe numbers to replace the SK16 and F2 glasses in the triplet design. If I can find them out there we can make this lens a lot easier and cheaper.
Hezz
I sent the files to your e-mail address. The three attachments where about 1.6 MB so I hope your hotmail will take them.
I'm hoping to find two themoset optical plastics of the right refractive index and Abbe numbers to replace the SK16 and F2 glasses in the triplet design. If I can find them out there we can make this lens a lot easier and cheaper.
Hezz
Duno about that hezz, depending on grade some of this acrylic is darn exspensive in pellet form or the sheet form. Nice work btw.
Trev
Trev,
The reason I want thermosets is because they are pourable at room temperature. They set up like epoxy. I just need to know all the index of refraction and Abbe numbers for all of the kinds of clear thermosets. And I need to study some more about substituting plastics for glass because it is not an exact substitution. Then once I find the best substitutes I can reoptimize the lens.
By the way here is a four hour ray trace of 10 billion rays for the plastic tessar above. The corners are slightly dim but it may be the ray tracing algorythm because it does random places.
Trev,
Would you know enough about light transmission to venture a guess as to how many photon rays would be in a real situation. I would think over a trillion in an area as big as we are doing here and with the bright lights.
Hezz
The reason I want thermosets is because they are pourable at room temperature. They set up like epoxy. I just need to know all the index of refraction and Abbe numbers for all of the kinds of clear thermosets. And I need to study some more about substituting plastics for glass because it is not an exact substitution. Then once I find the best substitutes I can reoptimize the lens.
By the way here is a four hour ray trace of 10 billion rays for the plastic tessar above. The corners are slightly dim but it may be the ray tracing algorythm because it does random places.
Trev,
Would you know enough about light transmission to venture a guess as to how many photon rays would be in a real situation. I would think over a trillion in an area as big as we are doing here and with the bright lights.
Hezz
Attachments
Hezz i can get the exact calcutlation for this if you'd like, my mrs has studdied quantum machanics and has all of the formulas for this but my rough guess would be well over a trillion, it depends on how manny numbers that comp of yours can take lol. But yeah light is fasinating stuff, once u know about it and have learnt what its made up of u see how easy a tv works and how dangerous one can be (ie: Xray radiation!!).
Trev
Trev,
That would be really cool if it is not too much work. The computer can do almost any amount of numbers it's just a matter of how long you want to leave the computer to crunch numbers unattended because it consumes the entire CPU resources. You can't do it in the background while doing other things.
I'm finding that there are more optical grade thermosets than I originally thought however some materials that may work well might not have full refractive index equations published with them because the material is usually used for other things.
It will take some time and more knowledge on my part. I know this is slightly pie in the sky trying to make a state of the art lens on the cheap but we can try.
Cruser,
I got an e-mail back saying your hotmail account didn't get the e-mail with the attachments. If you have another e-mail address where I can send larger attachments let me know otherwise I can send you some laser printed copies in the regular mail if you want.
Hezz
That would be really cool if it is not too much work. The computer can do almost any amount of numbers it's just a matter of how long you want to leave the computer to crunch numbers unattended because it consumes the entire CPU resources. You can't do it in the background while doing other things.
I'm finding that there are more optical grade thermosets than I originally thought however some materials that may work well might not have full refractive index equations published with them because the material is usually used for other things.
It will take some time and more knowledge on my part. I know this is slightly pie in the sky trying to make a state of the art lens on the cheap but we can try.
Cruser,
I got an e-mail back saying your hotmail account didn't get the e-mail with the attachments. If you have another e-mail address where I can send larger attachments let me know otherwise I can send you some laser printed copies in the regular mail if you want.
Hezz
ok guys i tested the diylabs triplet on the sgi 17.3" widescreen i guess i had smoke in my eyes cause its not gonna work its real close but NOT!!!
but what i did find was the 3m 9800 ohp triplet works flawless
its a 342mm fl triplet complete focus corner to corner yeah baby its finaly running sweet i took it to its final home and i will get some screen shots up real soon
so all you guys that want to use a 17" widescreen lcd go for it you wont be dissapointed the screen door is a non isue with this at 100" diagonal at 3 feet from the screen and the colors OH MY
the clarity OH ME OH MY!!! cmv1515 ha i laugh at that lcd !!!!
SGI HAS WON RESPECT FOR THIS LCD its 6 years old and its the best looking lcd i have ever seen period and its a diy'ers dream to dissasemble and mount
but what i did find was the 3m 9800 ohp triplet works flawless
its a 342mm fl triplet complete focus corner to corner yeah baby its finaly running sweet i took it to its final home and i will get some screen shots up real soon
so all you guys that want to use a 17" widescreen lcd go for it you wont be dissapointed the screen door is a non isue with this at 100" diagonal at 3 feet from the screen and the colors OH MY
the clarity OH ME OH MY!!! cmv1515 ha i laugh at that lcd !!!!
SGI HAS WON RESPECT FOR THIS LCD its 6 years old and its the best looking lcd i have ever seen period and its a diy'ers dream to dissasemble and mount
Cruser,
what is the distance of the lens to the screen at 100 inches diagonal for the 3M 9800 triplet.
Hezz
what is the distance of the lens to the screen at 100 inches diagonal for the 3M 9800 triplet.
Hezz
Ok. I have one oportunity to buy this lcd in my country for $550 used with the appropriate video card. So in addition I will need a 10 inch and a 15inch FL fresnel that is 15.75 inches square correct? So I guess Cruser and the group buy thing is the most economical option? Are there any other cheap options?
Cruser, when you doing another group buy for these fresnels? I may want to buy the monitor first and than the fresnels when I get more cash. Can we expect a group buy on these on a fairly regular basis? Say every 45 days or so?
Cruser, when you doing another group buy for these fresnels? I may want to buy the monitor first and than the fresnels when I get more cash. Can we expect a group buy on these on a fairly regular basis? Say every 45 days or so?
ace,
how much are those 3m triplets? Are they also 65mm diameter?
Will a crt projection lens with 150mm diameter work for sure?
The surplus shed fujinon is large diameter but wont work with large lcds correct?
how much are those 3m triplets? Are they also 65mm diameter?
Will a crt projection lens with 150mm diameter work for sure?
The surplus shed fujinon is large diameter but wont work with large lcds correct?
the lens is at 5' 9" from the screen to get 100" diagonalHezz said:
dracul said:
i do not know if it will work on that mobo but i just cant unerstand why you would build a projector around a specific motherboard/videocard just dosent make sence to me
Cruser,
Thanks for the information. For my room that throw would be too short. But I would still be very interested in seeing your results. I have figured out a way to make the high end glass cooke triplet for a reasonable amount of money but I don't have access to a lathe yet. Plus I will have to build a small kiln. If you would still like a copy of the lens plans let me know were I can send a larger attachment. Or maybe your hotmail account will accept only one file attachment. In that case I will have to zip or rar them all together.
Hezz
Thanks for the information. For my room that throw would be too short. But I would still be very interested in seeing your results. I have figured out a way to make the high end glass cooke triplet for a reasonable amount of money but I don't have access to a lathe yet. Plus I will have to build a small kiln. If you would still like a copy of the lens plans let me know were I can send a larger attachment. Or maybe your hotmail account will accept only one file attachment. In that case I will have to zip or rar them all together.
Hezz
Cruser,
Are you not getting my emails? Anyway I was just wondering about the fresnels for the sgi 1600sw. I was thinking of getting a pair right after I get the 1600sw from my country here. I have only one oportunity to get it here. Will you hold another group buy? Should I not wish to wait long do I have any other reasonably cheap options? I dont want to split. I want one double fresnel.
Are you not getting my emails? Anyway I was just wondering about the fresnels for the sgi 1600sw. I was thinking of getting a pair right after I get the 1600sw from my country here. I have only one oportunity to get it here. Will you hold another group buy? Should I not wish to wait long do I have any other reasonably cheap options? I dont want to split. I want one double fresnel.
Dracul,
I could be wrong but I always thought the group buy that cruser carried out was for another set of fresnels. I think the large ones that he ordered were just a special order and were expensive. They cost him like 100 USD each. So 200 USD for the big fresnels. However, he has not yet disclosed the source were he got them as I am aware.
Dnt32,
Of course the ceiling mount would help some as the screen is usually higher this would reduce keystoning some but whenever the projector is not mounted at the centerline of the image it will have some keystoning. Most DIY projectors with the exception of ones like Ace's are too big to be ceiling mounted. And because of the short throw OHP design would be right in the way of the people watching the screen.
Hezz
I could be wrong but I always thought the group buy that cruser carried out was for another set of fresnels. I think the large ones that he ordered were just a special order and were expensive. They cost him like 100 USD each. So 200 USD for the big fresnels. However, he has not yet disclosed the source were he got them as I am aware.
Dnt32,
Of course the ceiling mount would help some as the screen is usually higher this would reduce keystoning some but whenever the projector is not mounted at the centerline of the image it will have some keystoning. Most DIY projectors with the exception of ones like Ace's are too big to be ceiling mounted. And because of the short throw OHP design would be right in the way of the people watching the screen.
Hezz
No, they were 15 inch x 15 inch fresnels with no missing corners. The group buy was for these larger fresnels that could be used to project the entire 15 inch and larger lcds.
Cruser, I want these fresnels. What should the specs be and where can I get them at roughly the same price you got them for?
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