I would say high buddy cos if we use a crap frensel it will also change our colour of our lcd, it is also the main light plane for the lcd so it is important. Also all frensels disolour, look at some ohp's that are getting on in age, there frensel is yellow! so they dont last forever either but enough for our needs. This process is just sped up by the more light we throw at them.
Ok to the others, i am or was just stating facts in here, this is for you to learn and its not an argument, if monkey dont see, monkey dont know. However i am not telling people to stop buying this lens from allan, its totally your choice and your money, i am just telling you guys a few facts for your OWN good, and trying to save you guys disapointment in the long run. I myself wouldnt buy it, 92% is aceptible but after having somthing better, i wouldnt go back after seeing the big diff it makes, but thats me , and not you, so guys after this i hope you guys can see that im just stating facts and not trying to argue or run allan down.
Trev
ok this is a question i need alan to give a straight forward and honest answer to . what is the transmisivity of your 12.2 fresnel?
i have used many of those fresnels in the past and im curious to know
i have used many of those fresnels in the past and im curious to know
Cruser, the transmisity of our 12.2x12.2" fresnel lens is also 92%. Also, we have an antiglare addititive with the acrylic, which I believe changes the angle of refraction of those lenses so that as much light as possible will go through the lens instead of reflecting back toward the lamp side of the projector ... this makes for a more efficient light engine.
with that being said ill take 4 sets now!!! i have used your 12.2 fresnel in numerous projectors and i can honestly say its all good
for $50.00 a set ,if you dont buy these your nutz. now i feel like i was smoked on the $100 fresnels i just bought.
oh yeah thats $100 EACH
for $50.00 a set ,if you dont buy these your nutz. now i feel like i was smoked on the $100 fresnels i just bought.
oh yeah thats $100 EACH
Sounds GREAT, cruser! About those $100 fresnel lenses, those places probably have warehouse fees and stuff like that, whereas my operating costs are very low, and I'm also not making a profit off of these first several lens orders (the pre-orders), so that's probably why the difference in cost.
Just in case anyone is interested, I'd be willing to cut the price per lens for case orders (10 lenses per case) if you are wanting to re-sell these lenses. I'm open to any partnerships for these new fresnel lenses.
Just in case anyone is interested, I'd be willing to cut the price per lens for case orders (10 lenses per case) if you are wanting to re-sell these lenses. I'm open to any partnerships for these new fresnel lenses.
I never heard of anyone having to cut the corners of the lens for shipping purposes!
I'm not saying theres anything wrong with the lenses... and for that price anyone should jump on them... but I dont think they are custom at all. Sounds too much like a stock size your buying in bulk. No way is this a totally custom run of fresnels. But thats besides the point.
JCB
www.diybuildergroup.com
I'm not saying theres anything wrong with the lenses... and for that price anyone should jump on them... but I dont think they are custom at all. Sounds too much like a stock size your buying in bulk. No way is this a totally custom run of fresnels. But thats besides the point.
JCB
www.diybuildergroup.com
AWI get their lenses from japan, i know where from, they are non custom and the charges are due to shipping charges, quality, tax and import duties, not forgetting a profit on top.
I doubt that as a 210mm x 210mm size frensel with anti glare is over $250 for a single lens, not even pro projectors use these frensels in the medium range because of their exspence. If your frensels are green on the surface and made of glass, then they do have the anti glare, otherwise no they dont. The anti glare has to be on the facing surface or it wont work, weather in the material or not.
Trev
Custom Lens
Yes these are custom lenses. We are purchasing a custom lens mold, which will need to be milled from an aluminum block for (I assume) injection molding. I requested that the corners be cut because we have purchased perfectly square lenses in the past and the right-angle corners tend to crack easily and puncture bubblewrap when I ship them.
As for the anti-glare. It is not a coating, but rather a different grade of acrylic. It does not completely remove reflective glare such as with most newer CRT screens (with the purple coating), but rather simply reduces any feedback/input from other than the light source. The additive, as I have explained, alters the angle of refraction of the fresnel lens.
Bttom Line is that these lenses will actually work with LCD panels up to 17" diagonal without cutting off any of the image, which hasn't been possibly previously without dropping a large sum of money.
Yes these are custom lenses. We are purchasing a custom lens mold, which will need to be milled from an aluminum block for (I assume) injection molding. I requested that the corners be cut because we have purchased perfectly square lenses in the past and the right-angle corners tend to crack easily and puncture bubblewrap when I ship them.
As for the anti-glare. It is not a coating, but rather a different grade of acrylic. It does not completely remove reflective glare such as with most newer CRT screens (with the purple coating), but rather simply reduces any feedback/input from other than the light source. The additive, as I have explained, alters the angle of refraction of the fresnel lens.
Bttom Line is that these lenses will actually work with LCD panels up to 17" diagonal without cutting off any of the image, which hasn't been possibly previously without dropping a large sum of money.
Pre-Order Now Available
To all who are interested in pre-ordering either the 13" FL lens or the Dual Focus (13" and 8.67" FL's) lens, both are now available for pre-order at www.diylabs.org/projector/parts.htm by clicking on the left side. The price of the F15SPLIT is $29.99, while the F15DUALSPLIT (Dual FL split lens) came out to be $52.65. Please email me if you have any questions/comments about manufacturing, quantity pricing, or other aspects of the lens. Also feel free to post questions here in the forum as well. Thanks for your support with this group buy!
To all who are interested in pre-ordering either the 13" FL lens or the Dual Focus (13" and 8.67" FL's) lens, both are now available for pre-order at www.diylabs.org/projector/parts.htm by clicking on the left side. The price of the F15SPLIT is $29.99, while the F15DUALSPLIT (Dual FL split lens) came out to be $52.65. Please email me if you have any questions/comments about manufacturing, quantity pricing, or other aspects of the lens. Also feel free to post questions here in the forum as well. Thanks for your support with this group buy!
Allan, trust me, ive done one hell of alot of research into this and there is no additive, anti glare can only be a coating in optics, not an additive as an additive will loose us more light within the optic its self, and will not work as an additive due to refraction of light.
For a custom mould to be made for a normal pcx lens of 75mm is $2k, thats just a blank lens mould, and thats not including a lens or any polishing of a lens, nor materials, it is also a simple mould. For a frensel of your size, thats atleast $5k and up, they are a work of art and can only be machined by a special machine to get the mould right, they are extreme precision, and can not be made overnight. They are also made out of high tensile steal, that alone would cost $1k unmachined for that size.
Bottom line is: They are cheap cos they come from china, and they have cut corners and stock specs cos they arent custom.
Fair enough they are a good deal, but why must you lie about where they are comming from or their specs?
Ace, I don't appreciate you calling me a liar. I'm well aware of how expensive the lens molds are - I have a total of $3k invested right now with an additional $2k as soon as the lenses are ready. So $5,000 for 100 lenses = $50 per lens, which is almost exactly what I am charging. Also, as brainchild says - glass lens molds are closer to about $500-100 depending on the size of the lens. Frankly, I'm not sure why we are arguing about this - I started this group buy originally to keep DIY Labs up to speed and in the game and to help out the great many people who have 15" or larger LCD panels, but so far that help doesn't seem well-received by a few of people. If you don't think I should offer these lenses, then just say so please.
Finally, a note on transmisity from earlier... even if your fresnel were made from 100% transmisity acrylic, the lens would still not have nearly that much efficiency because the angle of each groove causes some reflection of light back towards the light side. You'll notice that if you look at the underside of your fresnel during operation, you can see it, meaning that light is reflecting from the lens back at you. If you look at a glass lens or even a sheet of glass, you'll not see the material nearly as much, yet they have about 95% transmisity at best. The sad truth is that everything we add to our projectors eats up light. When you consider than the LCD itself consumes all but about 5%-10% of incoming light, the transmisity of a fresnel lens becomes less significant as long as the efficiency isn't terrible.
Finally, a note on transmisity from earlier... even if your fresnel were made from 100% transmisity acrylic, the lens would still not have nearly that much efficiency because the angle of each groove causes some reflection of light back towards the light side. You'll notice that if you look at the underside of your fresnel during operation, you can see it, meaning that light is reflecting from the lens back at you. If you look at a glass lens or even a sheet of glass, you'll not see the material nearly as much, yet they have about 95% transmisity at best. The sad truth is that everything we add to our projectors eats up light. When you consider than the LCD itself consumes all but about 5%-10% of incoming light, the transmisity of a fresnel lens becomes less significant as long as the efficiency isn't terrible.
Ring Edmonds Optical and get yourself a quote, moulds start at $2k. China and the usa have diffent economies hence prices and quality.
Maybe, but that's Edmunds, and I'm not using them. If a different company deals more exclusively with custom lens molds and injection molds, then they might have a better manufacturing process. The reason I feel that my lenses are truly custom (asside from the contract that I have with the manufacturer) is that you won't find these lenses used anywhere else. There aren't any OHP's that large, and I can't imagine where else they would be useful. Also I'm able to chose any design I want - could've made the lens triangular if I had wanted to.
Allan, im not arguing, im just stating facts to others in this forum who i beleive deserve to know what they are getting first.
The rings and all have nothing to do with the transmisibility, its obvious rings chew light, but the transmisity is actually the transmisity of the actual materal that the frensel is made out of, we all know that ring pitch and ring angles all chew light and thus some are better then others, thats a whole new ball game that i wasnt going into.
The reason i stated that you wer a liar was because on the additive in the acrylic, im sorry but it doesnt igsist in optics, the only aditaves you will find are additives to purify the glass to give it more transmisibly, only anti glare can be a coating.
As ive said before, im only stating facts, not arguing or having a go at you directly. I beleive i have posted enough facts in here for people to learn, and what there is to look for in a frensel when purchasing them, i could go on forever in here but lets face it, this is a group buy and lets all carry it on as planned.
No hard feelings Allan.
Trev
The rings and all have nothing to do with the transmisibility, its obvious rings chew light, but the transmisity is actually the transmisity of the actual materal that the frensel is made out of, we all know that ring pitch and ring angles all chew light and thus some are better then others, thats a whole new ball game that i wasnt going into.
The reason i stated that you wer a liar was because on the additive in the acrylic, im sorry but it doesnt igsist in optics, the only aditaves you will find are additives to purify the glass to give it more transmisibly, only anti glare can be a coating.
As ive said before, im only stating facts, not arguing or having a go at you directly. I beleive i have posted enough facts in here for people to learn, and what there is to look for in a frensel when purchasing them, i could go on forever in here but lets face it, this is a group buy and lets all carry it on as planned.
No hard feelings Allan.
Trev
Trev,
Thank you for your post - I'm glad that we are in agreement about the rings issue. So is your feeling that the lenses I have purchased are actually good, especially for the money, regardless of how they may be manufactured and what country that comes from?
Also, would you be interested in me getting specifics about the anti-glare from the manufacturer? I know we've beaten that issue to heck, but if you're interested I'll be happy to ask them and post it here. Thanks!
Thank you for your post - I'm glad that we are in agreement about the rings issue. So is your feeling that the lenses I have purchased are actually good, especially for the money, regardless of how they may be manufactured and what country that comes from?
Also, would you be interested in me getting specifics about the anti-glare from the manufacturer? I know we've beaten that issue to heck, but if you're interested I'll be happy to ask them and post it here. Thanks!
Well no doubt they are a good buy, the quality is sound and will work well, i think its irrelivant where they come from and weather they are custom or not, or what you pay for them. At the end of the day, we all want gear that works, we want a good performance vs price level and i would say for the price you will get good results with these lenses, but dont exspect the best. Ofcourse we are not all aiming for the best either so thats in mind also.
The issues i brought up was to make people aware of what to look for and how to determine price vs quality, ive also stated how important optics are in a system even with a 4% gain or loss. I may have put it abit harshly to you Allan as you are the seller of these lenses, but by all means, no pun was intended at all.
Now ive stated the facts, i know for a fact that there isnt antiglare as an additive in a lens at all and i wont carry on with this due to this being your group buy thread, and for the respect of the other readers/ members, but however now that people know what to look out for and know the facts, at the end of the day its their choice. By all means would i never tell a person not to buy anything from anyplace, as its their choice and their responsibility to know what they are buying. Frensels havnt had much technical talk in here regarding specific specs other then ring pitch, grouve number, and focal, so its the sole reason why i brought this up in here in the first place lol.
And on that note ill leave it at that.🙂
Trev
Trev, thanks for all of that. Again, I appreciate your comments. Hey, I'm going to be adding a "theory behind fresnel lenses" page to my website (a more technical update to what I already have). I don't suppose you would want to contribute? Email me and we'll talk. Thanks! 🙂
hi alan,
sorry to see your thread degrade. i'm sure folks in this forum
can tell who is sincere and what will work best for them. i think
you will find much support for your new fresnel lens.
thanks for all the leg work on getting these lenses.
just for interest, i included a photo of a fresnel mold i own. it
is made of soft alloy, easy to machine. all the best in your ventures, tony
sorry to see your thread degrade. i'm sure folks in this forum
can tell who is sincere and what will work best for them. i think
you will find much support for your new fresnel lens.
thanks for all the leg work on getting these lenses.
just for interest, i included a photo of a fresnel mold i own. it
is made of soft alloy, easy to machine. all the best in your ventures, tony
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