RGB laser, help please!!

[p1t8ull]

Does anyone else out there agree with White-Light and think that using 445nm for the blue in an RGB projector pulls other colour mixes down in brightness causing reduced luminosity of the projector overall?

[Stoney3K]

Does anyone else out there agree with White-Light and think that using 445nm for the blue in an RGB projector pulls other colour mixes down in brightness causing reduced luminosity of the projector overall?

If you consider equal power, it probably will.

But if you compare a 2W or 4W dual or quad 445nm with a 457nm DPSS, I do think the winner will be quite obvious.

And still, that quad 445 won't break as much bank as the 457 or 473 you would need to buy to get some decent brightness, and it'll modulate a lot better.

Furthermore, consider reliability: If a 473 or 457 decides to fail on you during show-day, it's much too expensive to keep a spare on hand. On the other hand, having a spare $200 445nm module in your tool kit is just as easy as you would keep a few spare gas discharge lamps.

[norty303]

However, its personal. I haven't seen 457nm in action myself although clearly its heading in the right direction from the wavelength point of view for brightness.

I don't know what my opinion is about pulling colour down as I've never seen a 457nm myself, however I do have an opinion that advice offered by people who have no direct experience of a particular situation should be considered as subjective, rather than de facto.

[kl79]

ok, I've seen 457nm, it's a beautifull color....but I seen it before "the revolution" (445nm)..
I must see my friend and compare now..

I think, people with some money should go for a 457nm, because of the spot quality. (you cannot play a decent graphic show with those multimode 445nm diodes.)

[Stoney3K]

ok, I've seen 457nm, it's a beautifull color....but I seen it before "the revolution" (445nm)..
I must see my friend and compare now..

I think, people with some money should go for a 457nm, because of the spot quality. (you cannot play a decent graphic show with those multimode 445nm diodes.)

I will have to agree with that. If you want to go graphics, 457 is a better choice because of its single mode (round) beam. The 445's will cause smearing on the graphics because the beam is much wider.

Take care with modulating the 457 though, it might be a little more sluggish than your direct diodes, but depending on your setup, the green may be even slower.

If you want to do graphics, you do need to take a good look at your red lasers too. 635nm is a big no-go, with a wide flashlight beam, 650 may be too dark for your choice. Take a look at 642nm for red.

[p1t8ull]

Well graphics capability rather depends how well your 445nm beam is corrected and the specification of the other lasers in that RGB..
Yea an un-correected 445nm diode would struggle with graphics but it's not hard to make 445's with 3.5mm beams and under 1mR divergence with a very square spot shape, in one case I made one with under .9mR. Looked pretty good doing graphics to me

[danielbriggs]

Does anyone else out there agree with White-Light and think that using 445nm for the blue in an RGB projector pulls other colour mixes down in brightness causing reduced luminosity of the projector overall?

Yeah buddy!
Have you seen what 445nm does to the yellow distribution?!
Fire up a cuppa, cos you need to repalletise you're whole damn chrominance and luminance alignments after readdition.

With all this blue confusion talk; I just took the whole lot out... (gold and green are quite well balanced as is )
You can't have nuffin' good in blue these days; they even took the blues ones out of bloody Smarties!

Hurumph!

[danielbriggs]

I wasn't making a recommendation based on value for money which is why I was 1st to point out that its a far more expensive option. If you want value for money 445 wins hands down.

It also has nothing to do with Chroma which I still rate Stoney provided its used properly ie by looking at the white triangle instead of the white spot in the centre, taken in that context I believe its highly accurate. In the past others and myself (before I saw the light) were obsessed with the very obvious central white spot which meant that real life and the programme cleary didn't match up in terms of white balance prediction. However, Steve Milani's latest projector's spec combined with the wider white triangle shows that predictions are far more accurate than was previously thought as his projector shows a cold blue icy white which taken on the spot method was clearly outside of the white balance area but taken using the white triangle method is clearly within the white area and within the area you'd expect to find it for an icy blue colour. So yes I do believe its accurate and has had unfair press from memebers on here who like me, interpreted the graph wrongly in the 1st place based on the obvious white spot instead of the less obvious white triangle. You can't blame a programme for user error!

However, explanation over, I don't make a recommendation here based on Chroma.

The reason I'd take 457 over 445 money allowing is:

1. 445nm makes a nice white but I still believe it pulls other colour mixes down in brightness causing reduced luminosity of the projector overall. I still like 445 as an individual colour but I don't like projectors with it in as much eg 473 because of the dulling effect it appears to have on many mixed colours.

2. 457 is that little bit brighter than 445nm watt for watt

However, its personal. I haven't seen 457nm in action myself although clearly its heading in the right direction from the wavelength point of view for brightness. I have heard from others though that its still a deep blue whilst offering the greater luminosity. McCarrot would really be the best person to comment here as I believe he both sells and uses 457nm.

I would personally choose it over 445nm myself anyday given the luminosity downside to 445nm which I quite frankly detest. In fact money allowing I'd take 473 over 445 for colour anyday, simply because I'd rather compromise depth of blue than projector luminosity and thus impact.

I've never heard anyone in a club say that blue isn't dark enough. I have heard people say though I wish the lasers were brighter. Horses for courses.

I know most would recommend 445nm as it has a large following especially given its price drop and thats fine. I'm in a minority who do not like it. If the OP wants value for money then 445 is the way to go.

Niccceeee....

[White-Light]

Does anyone else out there agree with White-Light and think that using 445nm for the blue in an RGB projector pulls other colour mixes down in brightness causing reduced luminosity of the projector overall?

I make my opinion on that based on the Kvant 1.6W that Martin brought to the UKLEM I attended. My view is and always has been they're amazing projectors for quality, in fact unbeatable in that regard. But what struck me that day was how much the projector seemed to favour the purple / violet end of the spectrum and how much some of the lighter mixed colours seemed dimmed by the presence of 445nm when compared to other projectors of a similar power there using 473. Subsequent videos have only confirmed this in my eyes. There's a definite loss of punch in my eyes on the lighter colours when 445 is in the mix.

As for anyone else not favouring 445, I believe Adam (Buffo) has said he prefers 473. However, I couldn't tell you his reasons.

Ultimately, though as I said above its presonal choice. 445 is very popular because of its true blue colour, nice white and fantastic price.

[FULLPRODUCCIONES]

Thanks for all your threads they have been really healpfull. My main problem with the 445nm is that in some clubs the color used to look more purple than normal.

Something similar also happen with the 650nm red, in some darker clubs you can see it that well, but yesterday when i use it on a club that was painted White, and i was able to see more red power than ever

This picture is using a 300mw 447nm CNI diode, it does look quite purple, the photo i toke it from about 80ft

http://img256.imageshack.us/img256/821/img0814vz.jpg


To check the problem with the red you can check this video, the first video i toke it from about 50ft away, the second is from about 120ft away (Laser is 800mw 650nm, 500mw 445nm and 300mw 532nm)

http://www.youtube.com/watch?v=uPtZX1lQsks

For all this i use a CANON EOS 550D with a 18-55mm lens. All with the same setting (picture and videos)

Any idea why this happens, or if i go with diodes like 640nm and 457nm this wont happen that often (my theory is that is more bright for my eyes in a controled situation this will also help in a regular day)

Thanks for your time