New thread started for the purpose of dispensing knowledge learned/earned THE HARD WAY!
In failure there lies answers
I'll start: Bought a HONKIN big 9 inch x 3.5 inch thick enlarger lens through Ebay.
Two really nice convex lenses mounted thusly )( .
Weighs in at 10 pounds.
F/L of 8.25 inchs.
Well I figured (being the optical genius that I ain't 😉 ) I'll bid this puppy and effectively "decrease" the height (or thickness depending on build style) of my projector. Took a gamble on it being able to "see all of my 12 inch panel" at 8.25 inchs. No sweat there .. followed a lucky hunch
It projects a dandy image..awesome brightness and extremely clear....
Here's the BUTTT..the image gets way out of hand at any throw distance at all. 6 feet away makes a 6 foot wide screen. My projector currently sits 12 feet away and the best I can do is project the entire wall..then put the player software on top of a black windows desktop..sans icons...then drag the player onto my screen. If I used this new lens I would need a barn wall at 12 feet LOL 😱
If I had the room I'd use it for a rear projection unit..no room...maybe I'll build a telescope!
zardoz... has learned a few lessons the hard way...for sure...
Mental note to self....learn more about optics
In failure there lies answers
I'll start: Bought a HONKIN big 9 inch x 3.5 inch thick enlarger lens through Ebay.
Two really nice convex lenses mounted thusly )( .
Weighs in at 10 pounds.
F/L of 8.25 inchs.
Well I figured (being the optical genius that I ain't 😉 ) I'll bid this puppy and effectively "decrease" the height (or thickness depending on build style) of my projector. Took a gamble on it being able to "see all of my 12 inch panel" at 8.25 inchs. No sweat there .. followed a lucky hunch
It projects a dandy image..awesome brightness and extremely clear....
Here's the BUTTT..the image gets way out of hand at any throw distance at all. 6 feet away makes a 6 foot wide screen. My projector currently sits 12 feet away and the best I can do is project the entire wall..then put the player software on top of a black windows desktop..sans icons...then drag the player onto my screen. If I used this new lens I would need a barn wall at 12 feet LOL 😱
If I had the room I'd use it for a rear projection unit..no room...maybe I'll build a telescope!
zardoz... has learned a few lessons the hard way...for sure...
Mental note to self....learn more about optics
Were the lenses double-convex or plano-convex? Did you use any other projection lenses in this setup?
Mistake 1. I bought an NEC 1545. Due to either stress on the cables, improper grounding, excess heat, or all of the above, I totally destroyed the thing.
Mistake 2. Bought a second one and I'm still using it. However, one edge of the panel did not get cooled as well as the rest of it, and I coincidentally (or not) have dead pixel giving me bright spots on that side of the panel. It's not that bad and not noticable by anyone but me, but it is there.
Long story short, be careful with this thing if you get it.
Mistake 2. Bought a second one and I'm still using it. However, one edge of the panel did not get cooled as well as the rest of it, and I coincidentally (or not) have dead pixel giving me bright spots on that side of the panel. It's not that bad and not noticable by anyone but me, but it is there.
Long story short, be careful with this thing if you get it.
Re: Crashed & Burned? or Lessons Learned...
Great experimental lens! Sounds like it would be great for the micro-panel guys. Or building an immersive experience for your Game Boy?
If it's really that clear, save it. The older DLP's gotta hit eBay someday.
There's no chance you still have an extra fresnel after the LCD somewhere, right?
It's a shame since that is a lot of light-gathering diameter. Have you thought about trying to use it as condensing lens on a lamp somewhere? This would be a good one for a lamp with a really flat reflector, maybe even a planar mirror.
In the meantime--take it camping, just in case you can't get a fire started.
Great experimental lens! Sounds like it would be great for the micro-panel guys. Or building an immersive experience for your Game Boy?
If it's really that clear, save it. The older DLP's gotta hit eBay someday.
There's no chance you still have an extra fresnel after the LCD somewhere, right?
It's a shame since that is a lot of light-gathering diameter. Have you thought about trying to use it as condensing lens on a lamp somewhere? This would be a good one for a lamp with a really flat reflector, maybe even a planar mirror.
In the meantime--take it camping, just in case you can't get a fire started.
afan: The unit consists of 2 plano convex lenses, to experiment I folded the arm down on my 3M9550, then projected from the surface of the OHP to my ceiling ~6ft.
lifter: Thats a drag about the first panel 🙁 And I know what you mean about the "dead pixel" issue. I have 3 dead pixels..no one else seems to see them...for me it's like a poke in the eye! New panel on the way as we speak...hoping this one is clear of dead pixels. (the trouble with buying laptop screens off of Ebay)
neededandwanted: I agree it's a prety awesome lens, another reason I bought it 😉 It came cheap ..something like $32.00 US dollars complete with shipping to Canada. No extra freznel, I'm still using my OHP as stock (untill I find a couple of nice freznels that are seperate). I originally wanted to use 400 watt drop lights for my light source (factory style MH) so eventually might use one of the lenses as a condensor.
zardoz...one mans trash is another mans treasure 😉
lifter: Thats a drag about the first panel 🙁 And I know what you mean about the "dead pixel" issue. I have 3 dead pixels..no one else seems to see them...for me it's like a poke in the eye! New panel on the way as we speak...hoping this one is clear of dead pixels. (the trouble with buying laptop screens off of Ebay)
neededandwanted: I agree it's a prety awesome lens, another reason I bought it 😉 It came cheap ..something like $32.00 US dollars complete with shipping to Canada. No extra freznel, I'm still using my OHP as stock (untill I find a couple of nice freznels that are seperate). I originally wanted to use 400 watt drop lights for my light source (factory style MH) so eventually might use one of the lenses as a condensor.
zardoz...one mans trash is another mans treasure 😉
I think that you should try to use these two big PCX lenses separately around your LCD and without your fresnel in OHP. The projection lens from the OHP should be used to achieve better screen size/distance ratio (as in your OHP now). To make this ratio even better, you should experiment with projection lenses of different focal length. As I guess, the bigger is FL, the more distance between the LCD and projection lens should be and the smaller the projected image would be achieved.zardoz said:
My english must be bad, I didn't understand lol
What are you saying, with the lens, the image is too big?
What are you saying, with the lens, the image is too big?
spent $150 builing a parkland plastics fixed screen and had to scrap the entire thing because it got bubbles in it after i adhesed it with contact cement. ended up going with a $30 painted screen (see my results thread for how nice it looks).
Lifter's dead pixel
lifter:
I'm gonna torture my 1545 to see how hot it can get. I've seen 130 degrees F so far with no problems yet. As for your dead pixel-try a Sharpie black marker- ablack dot is better than a white one!
lifter:
I'm gonna torture my 1545 to see how hot it can get. I've seen 130 degrees F so far with no problems yet. As for your dead pixel-try a Sharpie black marker- ablack dot is better than a white one!
Once upon a time!
Once upon a time, there was a young ferret head called Mick.😀
Thought he might save a few bucks and build his own stuff, 'How hard can it be', said Mick.
Crashed and burned with that plan!😀
Oh, dear! So far, its been an awesome journey!
Thanx greatly to diyaudio for enlightening me!
Now, a much wiser Mick reckons, 'Ah well at least i'm not the only doughnut!'😛
Appentice for life now me thinks!!!!!
Once upon a time, there was a young ferret head called Mick.😀
Thought he might save a few bucks and build his own stuff, 'How hard can it be', said Mick.
Crashed and burned with that plan!😀
Oh, dear! So far, its been an awesome journey!
Thanx greatly to diyaudio for enlightening me!
Now, a much wiser Mick reckons, 'Ah well at least i'm not the only doughnut!'😛
Appentice for life now me thinks!!!!!
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