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Thread: Can Lasercut vary glass tube power whilst raster engraving to give relief effect?

  1. #1
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    Can Lasercut vary glass tube power whilst raster engraving to give relief effect?

    As title, can Lasercut based machines vary the power pixel by pixel from bitmap colour information to raster engrave with variable intensity to give a relief/variable burn effect in say laser ply like an Epilog can?

    I understand the glass tubes have a minimal effective power, and I read that their power is varied by an analog voltage rather than PWM like the RF tubes. However, PWM at a high enough frequency and a low pass filter can effectively be a digital to analog converter, so what is there a practical difference?
    Last edited by john banks; 11-08-2011 at 4:53 PM.

  2. #2
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    I don't think so. However if I remember correctly, Rodne suggested that it may be possible. It would like to know too.
    Shenhui 1440x850, 130 Watt Reci Z6
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  3. #3
    My version of Lasercut 5.3 can do that by mapping a greyscale bitmap for a 3d effect.

  4. #4
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    Hi John, can you explain how it's done? Shenhui supplies LaserWorks with their lasers, I've heard it is the same but I don't know for sure.
    Shenhui 1440x850, 130 Watt Reci Z6
    Gerber Sabre 408

  5. #5
    I've got a Chinese laser, via Connecticut. It's a Jamieson LG-640. I started to answer your how to question, and realized that the 3d option (greyscale mapping) isn't built into the lasercut package, but in another application that came from Jamieson, called EZphoto. It's a plug in for Corel X4 that sets up the bitmaps for the LaserCut corel plugin. So, I guess I was wrong. LaserCut doesn't do this on its own. Sorry.

  6. #6
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    Do you get a varying depth of engrave/relief in your lasered material for different colours in your bitmap or does the software just process it to 1 bit depth bitmap and use dithering/half toning to get the greyscales so the engrave look good even though the final surface is fairly flat?

  7. #7
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    Does RetinaEngrave do this?

  8. #8
    You need to start with a greyscale image, like Gantry sells. The software maps the power to the greyscale (not color) such that the white is engraved the least, and black the most. It works much like the ULS or Epilog software.

  9. #9
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    Sounds great. I wonder if they do it with a higher density of "on" pulses for the black areas rather than varying the power of the laser. If the results look good I doubt it matters though?

  10. #10
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    RDCAM 5 does indeed do this. I tried it this morning.

    If you select "output direct" then it will map grayscales to power dynamically. Use the minimum and maximum power to select the range, I used 10 to 60% and played with both to prove that it respects these boundaries by engraving solid squares and watching the ammeter. Even with a solid black it does not run my tube above the maximum power.

    On its own this technique doesn't give enough contrast to the engraving if you use a grayscale photo, but it may be able to enhance a halftone effect or give more depth.

    Interested in how other users get on with this.
    Shenhui 1280 100W RECI

  11. #11
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    It can only be used for 3d engraving as it doesnt dither the image to 1/2 tones. Try fill a circle with a radius fill in Corel , black in centre , white at edges - should engrave as a dish.
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  12. #12
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    I am assuming that you are talking about a bitmap image. So I can create a circle in Corel with a gradient fill going from black in the center and white at the edges, export it as a bitmap, import in RDCAM. What do I do in the RDCAM bitmap settings to engrave it like a dish?
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  13. #13
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    Do what John Banks said....
    Rodney Gold, Toker Bros trophies, Cape Town , South Africa :
    Roland 2300 rotary . 3 x ISEL's ..1m x 500mm CnC .
    Tekcel 1200x2400 router , 900 x 600 60w Shenui laser , 1200 x 800 80w Reci tube Shenhui Laser
    6 x longtai lasers 400x600 60w , 1 x longtai 20w fiber
    2x Gravo manual engravers , Roland 540 large format printer/cutter. CLTT setup
    1600mm hot and cold laminator , 3x Dopag resin dispensers , sandblasting setup, acid etcher

  14. #14
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    Quote Originally Posted by Khalid Nazim View Post
    I am assuming that you are talking about a bitmap image. So I can create a circle in Corel with a gradient fill going from black in the center and white at the edges, export it as a bitmap, import in RDCAM. What do I do in the RDCAM bitmap settings to engrave it like a dish?
    You would be using the grayscale image, not a bitmap.

  15. #15
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    The "Output Direct" option will not be available on older versions of LaserCut.

    Bitmaps can be greyscale, or any number of colors.
    Shenhui 1440x850, 130 Watt Reci Z6
    Gerber Sabre 408

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