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Thread: 100mW vs 300mW

  1. #21
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    Also, putting "just a point" into the drawing window will NOT give you a constant, unchanging 5V signal -- well, not from our software anyway... Our software does certain things "behind your back", and you will just have to trust that we know what we are doing, and the things that we do are for your own good
    Thanks for clarifying that 'point' Bill, it's what i was after, as i wasn't sure if it was standard behaviour or not for the FB3. I'm still curious 'why' the metered average signal was 0.17vdc/0.34vac on a single point in a frame, but as you've said you're not revealing more, i'll not press you! (not that it would do any good anyway!)

    Could this effect be anything to do with why both my lasers appear to be the same brightness? Would 3 1.5v AA batteries (4.5v) be ok to test the modulation line?

    Color signals are pulsed waveforms, and a meter will, at best, give you the average voltage. You need a scope to measure the voltages coming out of color lines, not a meter.
    Could low average voltage on some frames/patterns upset TTL lasers, if they happen to fall on or around the switching point? Would there be any practical use for having a software feature that provided a binary type (TTL) output over the analogue output? Again, i don't even pretend to know about these things but i'm trying to apply the logic that i do know, so any clarification is useful.

  2. #22
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    And besides that why are you paying for infrared?. Filter no filter. Who cares Price is set for 300mw@532nm and not for 200mw@1064nm+100mw@532nm.
    To clarify, they said they DO have IR filters, and that their power ratings are based on 532nm output.

  3. #23
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    Quote Originally Posted by norty303 View Post
    To clarify, they said they DO have IR filters, and that their power ratings are based on 532nm output.
    You said that they measured power before they put Ir filter on. If they did so this mean that they can't base their power on 532!
    I hired an Italian guy to do my wires. Now they look like spaghetti!

  4. #24
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    I think you'll find it didn't! Although maybe not quite clear on a second read, i said they do have IR filters and they measure power without IR [included]

  5. #25
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    Maybe your 100mw is overspec to 220mw. Then you can't really see the difference. Burning the tape test is good for units without IR filter. Because it's not visable light that burns it. It's IR leakage. You need some serious VIS power to burn tape. My 600mw green takes about 3-4 seconds to start something and I have to hold the tape very still. And yes I had measured all my lasers with power meter.
    I hired an Italian guy to do my wires. Now they look like spaghetti!

  6. #26
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    If you were going about testing lasers through a 'tape burn method' you would really need to go about it scientifically. There are a lot of factors that would be out of your control and some that are in your control. In my opinion if that is the type of test you were using it might be in your best interest to set up a testing platform. Something that would hold a unstretched piece of tape X feet away. I would say 5 feet away which would allow any extra IR to dissipate enough that it wouldn't drastically sway the results (of course assuming they have IR filters in place that wouldn't matter).

    If you can put a lens on the output side, this would give you a better chance to see the difference. The 100mw laser would have a hard time burning the tape. Using the same lens on both set ups will give you a better idea of the time it would take. I agree with Dr. Laser you do need quite a bit of power to burn tape. But the power density really will be the determining factor.

    With my 800mw Laser-Wave I don't have any problem burning tape. But placing a lens in front of it will cut tape like a red hot knife on butter.

    Some of the out of control factors include how well (or not well for that matter) the laser is focused on the galvos along with distance the laser travels internally (that shouldn't decrease a 300mw laser to ~100mw but it can affect it)

    Thats all I have to say now - I better get back to work

  7. #27
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    Ok, just because i KNOW you lot aren't sick of this thread yet, I took some pics with smoke for comparison (and had an awkward moment where my 2kw fogger got stuck on full for about 10 secs! It took a while to clear the flat, i can tell ya!)

    The orientation is the same as before although from the other side this time, so 100mW on left of pics, 300mW on right. Using either Alphalite or FB3, as i was trying to narrow down some parameters. The main thing that i noticed between the 2 DACS was that the smaller the image got (probably meaning less points) the less bright in comparison the FB3 was to the Alphalite. Now i know that Bill said earlier that the measuring across the intensity pins wouldn't tell much, however the difference between the Alpha and FB3 when running small lines and points was over 3vdc in most cases, with the FB3 being much reduced in brightness. I'd be curious to know why this might be the case on supposed TTL lasers, surely they're either off or on?

    Anyway, the first pic is a small circle, and you can see the output is visibly greater on the 100mW. The rest are all much the same, not too much to call between them.
    Attached Thumbnails Attached Thumbnails smallcirc.jpg  

    sinewave.jpg  

    sinewave2.jpg  

    flatbeam.jpg  

    flatbeam2.jpg  


  8. #28
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    I would agree with your statement - the only one that looks like the 300mw is winning is in the 4th picture down. The beams seem more distinguished.

    That last picture is awesome! Its like your shutter speed is close to the speed of light!

  9. #29
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    That last picture is awesome! Its like your shutter speed is close to the speed of light!
    I know, can't quite work out what causes that, unless its the way it scans down the image as it takes the photo. Had a couple come out like that

  10. #30
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    Yeah its most likely is the way the data is interpreted by the camera. I've never seen that happen before with a picture - what camera are you using?

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