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post #271 of 317 Old 07-10-2014, 08:29 PM
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Compared to most premium single chip DLPs this unit has more than double the light output while maintaining the same kinds of native and dynamic contrast. So someone who has a screen the size of yours can get an image as bright as one of your Sony 4K machines. I think the extra brightness really does a lot in terms of perceived contrast, sharpness, color, and overall enjoyment.

Also, what's interesting is that this projector is more in line, in regards to contrast at least, with .95" DMD projectors. ~3000:1 measured contrast seems pretty close to what you're getting on your modded .95" DC4 PD8130, right? Typically the smaller DMD only got around 1700:1 max measured native contrast. I also think the lens on this unit will make up for the difference in DMD size for image sharpness. Time will tell...
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post #272 of 317 Old 07-10-2014, 08:42 PM
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Originally Posted by Seegs108 View Post
Jeff was using the long throw lens. Those lenses are typically better with contrast. Sound and Vision got about 3000:1 with the stock lens which is the lens mine has. I'll measure with my Minolta CL-200 when it arrives on Wednesday. The unit only has 50 hours on it. From what I've read these are specialty .65" DMDs that were designated as "DC4" by some as they are graded and the top performing DMDs TI makes at this size. Though, I believe contrast is more affected by the light path and optics than what TI states is typical. Look at Sim2. They're able to achieve 7000:1 native contrast at full brightness with their Lumis line when TI specs the DC4 DMD to be much lower. It is possible Runco has added a few tweaks to the Delta OEM design to boost contrast over the HighLite 260? They've done things like this in the past. As far as differences in "software" I meant more along the lines of color management and dynamic iris algorithms which are intellectual properties (unless using a stock implementation, which I doubt either company uses) and will vary on units even if the hardware is the same. For example I've owned the Runco Q750i, Vivitek H9080FD, and the NuVision ProVu P2. All are the same projector internally but the DI implementation each varied in performance with the Runco taking the cake on visibility and transparency. It just seemed more well rounded of the three.
Yeah, agree re lightpath, it does matter. I did some extensive testing on a C3X a good while back. Got 10k+:1 on it in it's highest CR setting (Iris closed, max throw, etc) IIRC. Haven't heard that about the chipsets, I'm skeptical there. I got some inside info from the heads of one of the PJ companies I work with, but I don't have any hard data handy so not worth repeating here, been discussed here somewhere before anyway.

But we are OT a little, apologies to the OP or LED1000 lurkers.

Cheers
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post #273 of 317 Old 07-11-2014, 07:39 PM
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The LED models do have a dynamic black function, though it works slightly different. Instead of an aperture that opens and closes to dynamically change the amount of light that leaves the projector, the LEDs dim and brighten dynamically to do the same thing the aperture does. Then, just like dynamic black, dynamic gamma gets implemented to try and alleviate brightness compression artifacts.

I bought a Runco LS-10i, which is the same unit as your highlite 260 just in a different chassis and some intellectual property changes to the software. I've heard the dynamic iris on the Runco is better implemented compared to the DP 260. I'm pretty excited. This will be my first three chip DLP unit. I should have it next week!
Congrats, 3 chip is the business. I am guessing you found a deal on an ex-demo or used one? I don't know how good a deal it was but were you not tempted by a .95 3 chipper? I know most of the bargain .95 models don't have a DI.
I'll be very interested to hear your views, if it gets the Seegs stamp of approval maybe I'll have start looking for one

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post #274 of 317 Old 07-11-2014, 08:14 PM
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Congrats, 3 chip is the business. I am guessing you found a deal on an ex-demo or used one? I don't know how good a deal it was but were you not tempted by a .95 3 chipper? I know most of the bargain .95 models don't have a DI.
I'll be very interested to hear your views, if it gets the Seegs stamp of approval maybe I'll have start looking for one
It was a demo unit from a Runco dealer in Las Vegas. It has 50 hours on it. I didn't get the kind of deal I usually get, but I still think I could get my money back if I were to sell it down the road. I will say this is by far the most expensive projector I've bought thus far, by a decent margin (about double the next most expensive). You're right about there not being a lot of 3-chip .95" DLP units having a DI. Other than the Sim2 Lumis line (and then again it's only some of the units in that line that have them) I don't think there many other 3 Chippers that have one. The Sim2 Lumis line, even used, will still cost you $15,000+.

I think the culmination of all the parts will yield the best DLP image I've seen thus far. The light output, the nature of a 3 chip design (no rainbows), great motion, great ANSI contrast, classic 3 chip DLP color, Runco DI implementation, nice Konica Minolta lens, ect. I'm pretty excited.

With that said, let's not derail this thread anymore. Please PM me if anyone wants to talk about this further.

I'll post my impressions next week in Zombie's shootout thread.

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post #275 of 317 Old 07-14-2014, 10:21 AM
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FWIW, I have my Darbee set to %40. I also used max dynamic black. I've been experimenting, and to my eyes, those are the settings that work best for me.
I'll reiterate that you guys can wake me up when there is a 4k laser and lots of 4k content. Til then, I'm going into hibernation mode.
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post #276 of 317 Old 07-15-2014, 10:24 PM
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FWIW, I have my Darbee set to %40. I also used max dynamic black. I've been experimenting, and to my eyes, those are the settings that work best for me.
I'll reiterate that you guys can wake me up when there is a 4k laser and lots of 4k content. Til then, I'm going into hibernation mode.
These projectors are just so convenient. Nothing like having a worry free projector with a great picture.
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post #277 of 317 Old 07-16-2014, 09:34 PM
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These projectors are just so convenient. Nothing like having a worry free projector with a great picture.
yup, part of me definitely thinks not buying the f8500 and x35 and using that money towards an open box cine 1000 would have been a pretty ok thing. but that option wasn't really viable 14months ago, which was when I needed it to be.


but now, my plan was to find a decent LED projector in the 1500 range to compliment my jvc. but the time that happens, or I'm ready for it, I may be better off finding a high quality led projector instead. I honestly didn't expect buying one good LED projector to be cheaper than buy one good bulb based projector and one 'good enough' led projector.
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post #278 of 317 Old 07-17-2014, 05:38 PM
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I finally have the open box unit from Mike installed. I'm watching the Lego movie with the picture on a blue painted wall with white ceiling and a non light controlled environment and the picture is still amazing! Can't wait to see what it looks like with a screen in place.
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post #279 of 317 Old 07-20-2014, 11:22 AM
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Originally Posted by Seegs108 View Post
The LED models do have a dynamic black function, though it works slightly different. Instead of an aperture that opens and closes to dynamically change the amount of light that leaves the projector, the LEDs dim and brighten dynamically to do the same thing the aperture does.
A DI also increases CR; do any of the LED units use one?

At the prices they charge, they should.

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post #280 of 317 Old 07-20-2014, 11:43 AM
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A DI also increases CR; do any of the LED units use one?

At the prices they charge, they should.
Do you mean a physical DI device? I don't believe any of the current models do. Though, my understanding is that the LED dimming/modulation does the exact same thing a physical DI device does and once you include dynamic gamma the result is the same as it would be with a physical DI.

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post #281 of 317 Old 07-20-2014, 11:59 AM
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Yes, I mean a physical DI, which increases CR by reducing the aperture and blocking more stray light.

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post #282 of 317 Old 07-20-2014, 12:03 PM
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That's what I thought. Yeah, there aren't any out there. Instead of blocking a static amount of light from a lamp, the LEDs simply dim dynamically so there is less light to begin with. If you look at reviews the contrast numbers, both on/off and ANSI, don't seem to suffer from an issue of stray light. Contrast numbers are right in line with the best DLPs.

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post #283 of 317 Old 07-20-2014, 07:46 PM
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Originally Posted by Seegs108 View Post
Contrast numbers are right in line with the best DLPs.
Yes, and as you often say, those numbers aren't the least bit competitive with to LCOS.

A DI would at least double dynamic CR.[/QUOTE]

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post #284 of 317 Old 07-20-2014, 07:52 PM
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They are different technologies. Apple and oranges. Even Sim2 can't seem to manage more than 5000:1 native contrast with their top of the line models. They can manage 7000:1 if you're at the telephoto end of the zoom range. But that's still far from something like JVC. That is, however, right in line with Sony's 1080p models as far as native contrast goes. So DLP can still manage native and dynamic contrast to SOME LCoS models, just not JVC's but then again no digital projector out there can match them. These LED models seem to only manage 2500:1. My JVC DLA-X500 next to any projector out there will get blown away if we're looking just at contrast, but I have to say, the three-chip DLP Runco LS-10i I have here now looks excellent with contrast too and can trump the JVC in other areas.

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A DI would at least double dynamic CR.
Are you saying LED dimming and a DI? I don't think these LED models are anywhere near bright enough to have two contrast enhancement techniques implemented.

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post #285 of 317 Old 07-21-2014, 09:08 AM
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I'm not saying a physical DI will make LED DLP competitive with LCOS, but 2X CR is certainly a big improvement, especially starting from such a low value.

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post #286 of 317 Old 07-21-2014, 10:55 AM
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but, can you stack those technologies? they are doing the same thing. it's kind of like saying if you put TWO DI's on a projector, you'll get 4x the contrast ratio, and I don't think that's true either.


if the LED's dim, and there's hardly any stray light to block, then a DI wouldn't be nearly as effective. maybe it only results in a 5% increase in contrast, but DI's are 100% annoying, haha. but seriously, I have to think if it was a worthwhile feature to add, they would. so it's either not very effective, or it's much too difficult to implement correctly.
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post #287 of 317 Old 07-21-2014, 10:57 AM
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I'm not sure if he's under the impression they do the exact same thing. We'll have to wait and see what Noah says. Obviously a physical device is different but in practice (and the numbers support it) the LED dimming has the same effect a physical device has.

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post #288 of 317 Old 07-21-2014, 02:04 PM
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Originally Posted by fierce_gt View Post
it's kind of like saying if you put TWO DI's on a projector, you'll get 4x the contrast ratio, and I don't think that's true either.
If they're both physical apertures, one at the lamp and one at the lens, that may in fact be possible.

But for this discussion let's it's either lamp dimming or DI, in which case the DI wins on CR but loses on complexity and cost.

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if the LED's dim, and there's hardly any stray light to block, then a DI wouldn't be nearly as effective. maybe it only results in a 5% increase in contrast, but DI's are 100% annoying, haha. but seriously, I have to think if it was a worthwhile feature to add, they would. so it's either not very effective, or it's much too difficult to implement correctly.
Dimming reduces brightness, not the proportion of stray light.

Your conjecture on effectiveness contradicts the experience of JVC owners, including Seeg.

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We'll have to wait and see what Noah says. Obviously a physical device is different but in practice (and the numbers support it) the LED dimming has the same effect a physical device has.
How soon you forget:

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Yes, I mean a physical DI, which increases CR by reducing the aperture and blocking more stray light.
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That's what I thought.
It's well known that an iris, either static or dynamic, increases CR, which info is contained in many of your posts so I'm baffled that we're having this discussion.

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post #289 of 317 Old 07-21-2014, 02:20 PM
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Quote:
Originally Posted by noah katz View Post
If they're both physical apertures, one at the lamp and one at the lens, that may in fact be possible.

But for this discussion let's it's either lamp dimming or DI, in which case the DI wins on CR but loses on complexity and cost.



Dimming reduces brightness, not the proportion of stray light.

Your conjecture on effectiveness contradicts the experience of JVC owners, including Seeg.



How soon you forget:





It's well known that an iris, either static or dynamic, increases CR, which info is contained in many of your posts so I'm baffled that we're having this discussion.
I don't understand your point. We get the same ANSI and dynamic on/off numbers when using LED modulation as we do with this same light engine using a physical dynamic iris in the light path (this light engine is the the same as the PD8150's just without a DI and LEDs in the spot where the bulb normally goes). What exactly is your point? Why would we want two DIs or instead of the LED modulation only and physical device? I don't think I understand exactly what you're trying to say. I'm a bit confused.

If you're simply saying we should use two DIs to increase dynamic contrast I've already pointed out these projectors aren't bright enough for that and if they were pushed even more we'd be seeing dynamic gamma overused and the image would look awful during darker content. DG is already used a bit too much in my opinion on these models. I don't think I'd own one of these models of it were used any more. We'd have clipped whites in every dark scene as opposed to occasionally like how it's setup now.

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post #290 of 317 Old 07-21-2014, 02:39 PM
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I'm saying, again, that a physical DI gives higher CR than dimming the light source.

The fact that a DLP w/lamp and DI doesn't exhibit higher CR than a DLP w/LED's (me not realizing this explains our misunderstanding) must be because of better entendue (intrinsically less scattered light).

And maybe that means that there's little improvement to be had w/a physical DI.

Noah

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post #291 of 317 Old 07-21-2014, 03:49 PM
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Yeah, both the PD8150 and Q750i, for example, get basically the same ANSI and dynamic on/off even though one uses LED dimming and the other uses a physical DI. Both implement dynamic gamma to the same extent. I've had each here and compared side by side. The PD8150 had a very slight advantage in black level but we're splitting hairs here and this could have been unit to unit light engine/DMD variance.

Cine4home got 10000:1 on the PD8150 and 10500:1 on the Vivitek H9080FD (same Delta light engine). They measured 560:1 ANSI on the PD8150 but didn't publish the numbers for the H908FD but you should expect the same number because it's the same light engine and optics.

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post #292 of 317 Old 07-21-2014, 06:01 PM
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If they're both physical apertures, one at the lamp and one at the lens, that may in fact be possible.
my point was more to consider the law of diminishing returns. some projectors do have two iris's, but then why not have 10? at some point it's just not worth it anymore, perhaps with LED's even one is overkill.

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But for this discussion let's it's either lamp dimming or DI, in which case the DI wins on CR but loses on complexity and cost.
I'm not sure I agree. having never seen a DI I didn't need to turn off, I like the idea of dimming LED's because they can theoretically be MUCH faster, have more 'steps', and be completely silent in operation. I'd think the complexity of making it work well would be pretty equal between the two.


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Dimming reduces brightness, not the proportion of stray light.
less light equals less stray light. I'm not convinced the 'proportional' amount of stray light to focused light is the only important factor. on the same line of thought, LED's tend to be a LOT more directional too, so maybe just that fact alone makes a DI less effective? maybe there's less stray light from a LED source to begin with. a DI is a bandaid fix to a problem, perhaps LED projectors don't need this bandaid as much?
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Your conjecture on effectiveness contradicts the experience of JVC owners, including Seeg.
now I'm lost. jvc doesn't have an LED model, so I'm not sure how the experience with a jvc is applicable to how DI's work on LED projectors?

anyway, I see a DI doing two things(that are wanted)
1. reduces brightness during dark scenes to improve black levels
2. increases contrast by blocking some stray light


the first can be completely duplicated by dimming the led's, an iris would have no further benefit in that regard. so it's only that second one, and I'm just guessing here, but maybe because LED"s are more directional, they can control that stray light better, and CR's actually aren't improved that much on LED models. personally, the only reason I'd notice a DI is to get better blacks on dark scenes, so for me, a dimming light source is far better than a DI.
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post #293 of 317 Old 07-22-2014, 07:04 AM
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Yeah, both the PD8150 and Q750i, for example, get basically the same ANSI and dynamic on/off even though one uses LED dimming and the other uses a physical DI. Both implement dynamic gamma to the same extent. I've had each here and compared side by side. The PD8150 had a very slight advantage in black level but we're splitting hairs here and this could have been unit to unit light engine/DMD variance.
I also had the Runco LS5 (PD8150) and the Runco Q-750i set up side by side for 2-3 months. I can confirm that the CR was effectively the same on both units despite one using a DI and the other LED modulation.
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post #294 of 317 Old 07-22-2014, 09:41 AM
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Quote:
Originally Posted by fierce_gt View Post
less light equals less stray light.
It's the ratio of stray light to total light that affects CR, not just the absolute amount of stray light.

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...jvc doesn't have an LED model, so I'm not sure how the experience with a jvc is applicable to how DI's work on LED projectors?
Right, which I conceded.

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...maybe because LED"s are more directional, they can control that stray light better, and CR's actually aren't improved that much on LED models.
That's what I said.

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post #295 of 317 Old 07-23-2014, 12:41 AM
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Quote:
Originally Posted by noah katz View Post
It's the ratio of stray light to total light that affects CR, not just the absolute amount of stray light.
well, to be technical, that's what affects ANSI contrast ratio. but on/off contrast ratio is also very important. I'd argue that most DLP's have high enough ANSI contrast already, I'm never left feeling a bright image lacks depth. what I miss is the fades to black that actually get close to black. a good DI can darken dark scenes enough to make on/off contrast pretty comparable to the jvcs(pre-DI on them). I just never liked that I could always see the DI's working, and hear them, so the JVC was a more appealing option for those reasons. I speculate that a dimming LED could be fast enough, and obviously silent enough, do be a better option for achieving lcos-like on/off contrast from a dlp than a DI. whether it gets 5000:1 or 8000:1 ansi CR is less important to me since I seem to be totally thrilled with even less than that. while important, like with brightness, at some point it's not longer the weak link and I'd rather get other improvements. imo, the ability to achieve good results without using a DI is a good thing, as I've always found DI's to take away from the viewing experience. sometimes they are a necessary evil, but they are definitely a compromise. so I like options that provide equally good results without the use of one


we still have the question of whether or not a dynamic iris PLUS led dimming would be worthwhile or not, though. I just don't agree that a mechanical DI is better than LED dimming, if you had to pick just one. and this is only based on my experience with DI's, I've not seen the LED dimming. I just know I hate DI's
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post #296 of 317 Old 07-23-2014, 01:05 AM
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Quote:
Originally Posted by fierce_gt View Post
less light equals less stray light. I'm not convinced the 'proportional' amount of stray light to focused light is the only important factor. on the same line of thought, LED's tend to be a LOT more directional too, so maybe just that fact alone makes a DI less effective? maybe there's less stray light from a LED source to begin with. a DI is a bandaid fix to a problem, perhaps LED projectors don't need this bandaid as much?
While more directional than traditional arc lamps, are they more directional than lamp modules with reflectors? Having spent some time building my own projector in the past, the shorter the arc, the more collimated the light from the lamp assembly will be... that is one of the reasons these lamps are so pricey... not too many uses for small, bright, broad-spectrum collimated light sources. I realize the old-school DIY projector light paths are not at all similar to DLP, but the same need for collimation applies. no? It is more difficult to collimate a larger source... there is a tradeoff here, and I'm not sure LED is the easier source to collimate. The PT120 is 4.6mm in its largest dimension, while a short arc PJ lamp IIRC is ~1-2mm. It may very well be the case that LED has less scattered light than traditional PJ lamps, I honestly do not know how collimated LEDs are (and thus the amount of scatter). Are LEDs directional in general, or is that a result of the lenses typically applied on the lower power LEDs? I for one, would love to see a high-end LED DLP PJ with a dynamic iris... of course, I could not afford it!

"A wide screen just makes a bad film twice as bad. "
-Samuel Goldwyn

I wonder what he'd think about 3D IMAX?

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post #297 of 317 Old 07-23-2014, 01:54 AM
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Originally Posted by dougri View Post
While more directional than traditional lamp filaments, are they more directional than lamp modules with reflectors? Having spent some time building my own projector in the past, the shorter the arc, the more collimated the light from the lamp assembly will be... that is one of the reasons these lamps are so pricey... not too many uses for small, bright, broad-spectrum collimated light sources. I realize the old-school DIY projector light paths are not at all similar to DLP, but the same need for collimation applies. no? It is more difficult to collimate a larger source... there is a tradeoff here, and I'm not sure LED is the easier source to collimate. The PT120 is 4.6mm in its largest dimension, while a short arc PJ lamp IIRC is ~2mm. It may very well be the case that LED has less scattered light than traditional lamps, I honestly do not know how collimated LEDs are (and thus the amount of scatter). Are LEDs directional in general, or is that a result of the lenses typically applied on the lower power LEDs? I for one, would love to see a high-end LED DLP PJ with a dynamic iris... of course, I could not afford it!
I wish I had answers, but I really don't, only things I've observed. there may not be a strong correlation to projectors, but the LED bulbs I've used at home, as well as the raw LED's I've used for projects, have always been 'focused' in their raw forms. I actually had to do some mods to the lenses on my GU10 LED's so they didn't look like I stuck a bunch of flashlights in my ceiling. so I'm assuming led's are more focused by default. I've never seen an LED emit light backwards for example, and at 90* angles, very, very little is seen. in fact, moving from dead center to as little as 5* off axis can be the difference between blindingly bright and very dim.


but I think it'd be more interesting to look at the designs for projectors specifically, and I don't really have any knowledge of a comparison between a bulb and led source for projectors. I don't know if led's actually can be focused more precisely or not.

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post #298 of 317 Old 07-23-2014, 03:37 PM
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Originally Posted by fierce_gt View Post
I wish I had answers, but I really don't, only things I've observed. there may not be a strong correlation to projectors, but the LED bulbs I've used at home, as well as the raw LED's I've used for projects, have always been 'focused' in their raw forms. I actually had to do some mods to the lenses on my GU10 LED's so they didn't look like I stuck a bunch of flashlights in my ceiling. so I'm assuming led's are more focused by default. I've never seen an LED emit light backwards for example, and at 90* angles, very, very little is seen. in fact, moving from dead center to as little as 5* off axis can be the difference between blindingly bright and very dim.


but I think it'd be more interesting to look at the designs for projectors specifically, and I don't really have any knowledge of a comparison between a bulb and led source for projectors. I don't know if led's actually can be focused more precisely or not.
I've never played around with bare LEDs... just those with integrated lenses (the package includes an integrated plastic lens... some have reflectors as well now I think). When you say "raw LED's" are you speaking of the T1 (3mm) or T1-3/4 (5mm) packages with integrated lenses, or truly raw/exposed LED chips? Obviously the LEDs intended for household lighting have lenses/reflectors to mimic incandescent bulbs as closely as possible. I believe the phlatlight chips have a flat glass piece over the chip for protection (instead of a plastic lens), so maybe that is a good place to look for directionality of LEDs. I thought Mr. Katz knew a lot about optics, lamps, LEDs and such... do you know the skinny Noah?

"A wide screen just makes a bad film twice as bad. "
-Samuel Goldwyn

I wonder what he'd think about 3D IMAX?
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post #299 of 317 Old 07-23-2014, 06:56 PM
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Originally Posted by dougri View Post
I've never played around with bare LEDs... just those with integrated lenses (the package includes an integrated plastic lens... some have reflectors as well now I think). When you say "raw LED's" are you speaking of the T1 (3mm) or T1-3/4 (5mm) packages with integrated lenses, or truly raw/exposed LED chips? Obviously the LEDs intended for household lighting have lenses/reflectors to mimic incandescent bulbs as closely as possible. I believe the phlatlight chips have a flat glass piece over the chip for protection (instead of a plastic lens), so maybe that is a good place to look for directionality of LEDs. I thought Mr. Katz knew a lot about optics, lamps, LEDs and such... do you know the skinny Noah?
mostly the ones with the integrated lens, but I have seen a few attached to the circuit board directly, just not sure how typical they were.


I guess what I'm getting at, is that in nearly every instance I've seen, the led's have a more focused light path. it just seems weird that even when you'd want a dispersed light(like an incandescent bulb replacement) it seems like that's not possible with a single LED, or even an array of them unless they are pointed in all different directions.

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post #300 of 317 Old 07-23-2014, 08:40 PM
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Originally Posted by fierce_gt View Post
well, to be technical, that's what affects ANSI contrast ratio. but on/off contrast ratio is also very important.
To be technical, that includes on/off CR.

http://en.wikipedia.org/wiki/Stray_light

"Stray light is light in an optical system, which was not intended in the design. The light may be from the intended source, but follow paths other than intended, or it may be from a source other than the intended source. This light will often set a working limit on the dynamic range of the system; it limits the signal-to-noise ratio or contrast ratio, by limiting how dark the system can be."

Noah

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