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Thread: How much better is <1mrad vs <1.4mrad?

  1. #1
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    Default How much better is <1mrad vs <1.4mrad?

    Im looking at some projectors and I was curious to your experience, how much better is <1mrad vs <1.4mrad? What issues will I see with the 1.4 that I wont with 1? Is it a significant upgrade 1 over 1.4? I never owned a laser before so I wanted to ask for yalls advice. Thanks

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    There's more than that as to what makes a great laser projector, but I would personally buy the lowest divergence you can.
    However... if there's a big price difference and the areas you plan to use it in are fairly small <20m, it won't make much of a difference.
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    Since we are dealing with milliradians as they apply to beam divergence the answer is "Not much for your application"

    If you are trying to draw on scrim a football field away, it may make a slight difference though not unless you have something to compare it to. If you are interested in beam shows, you wont notice any difference.
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    What is considered small? Will there be notable difference at 50 feet? 100 feet? I'll probably do some night clubs but also probably some (on the smaller side) architectural mappings. Mostly will probably do medium scale art installations with it. Thanks for your feedback

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    What sort of power projectors? That will influence how big rooms and buildings (and therefore distance) whereby a lower divergence will/won't make a difference.
    2 other factors that make a good difference when mapping is the cleanliness of the beams, so you eliminate the fuzz on the edges, and the quality of the drivers and whether they are balanced nicely.
    Although they were more popular with DPSS lasers, I still use colour correction boards in some of my projectors as you can fine tune the start and tails so nicely.
    Frikkin Lasers
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  6. #6
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    3watt. That’s all i can afford right now. Im looking at the venus rgb vs the unicorn rgb.

    http://www.lightspaceusa.com/holiday-sales-event.html

  7. #7
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    Quick approximation... 1 millirad at 1000 meters gives you a one meter wide beam. 1.4 would be just less then a meter and a half wide.
    Your eye cant tell the difference, and the above assumes perfect lab grade lasers, which you will not be buying. Your beams will be oblong and fuzzy with bright spots due to diode physics at 1000 meters, not a clean circle like a classical gas laser would be.

    Steve
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    It’s good to be aware of divergence, but from experience I’ve found it rare for the real-life beam divergence to match the manufacturer’s quoted figures. Part the reason is that there are at least 4 different ways to classify beam diameter, so you’re not always comparing like with like. But moreover, I get the impression that the measurement process for some manufacturers is little more than taking a measurement with a school ruler of the spot size created at some distance.

    Higher end, (and hence more expensive), projectors will likely have more care taken in achieving the good divergence and reporting it more accurately. For budget projectors, just take the usual precautions in looking for something with good overall build quality, good reviews, and (I would say this ), all the correct safety features and labelling. And as far as the beam is concerned, as others have said, look for well matched and converged profiles, that don’t look too fuzzy. Taking a look at each colour in turn, as well as the white beam can be useful.

    The main thing is to enjoy what you get, and make some good effects/shows with it, for even today’s well-built budget projectors produce beams that are much improved on the early generation solid-state RGB projectors of just a few years ago.

    James
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    steve we gotta get my spiricon M200 up and running

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    @OP: Get the Unicorn - those are decent projectors.


    @James... part of the reason I picked this up!
    So many manufacturers don't know or care enough to document their specifications correctly.
    Another one: "50k modulation" gets slapped on every driver I see. After testing many drivers, most don't live up to this! (To me its rated speed is the -3dB point). For 99% of light show applications, driver modulation speed is not an important factor to consider, but on that rare time you go looking for a driver and need specific modulation capability it's frustrating to see the lack of care taken with "advertised specs".

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    - There is no such word as "can't" -
    - 60% of the time it works every time -

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