problems with picture engraving

[AR]

i got ugly horizontals lines all over my picture, and also outside of the picture area.
do you know the problem?

[Steve]

I am not sure what you meen by horisontal lines.

What cutter did you use? what material and QuickCAM settings did you use. What machine?

The cutter should not touch the material other than in the photo area.

From Quick CAM go to the HELP menu, Select TUTORIALS and then LITHOPHANE TUTORIAL.

This takes you right through the procedure with regard to feeds speeds stepover and depth of cut.

Could you take a picture of the cut part and send it to me by e-mail?

[Denford Admin]

Are you engraving pictures on the VersaLaser ??

If so I think Steve has got the wrong end of the stick here

email a photo to technical @ denford . co . uk. So we can post it up and see what the problem may be

[Steve]

I now understand you are using a laser to engrave the picture.

To try and print a picture with a laser on wood is dificult as slight variations in the wood will cause the image to be darker in some areas.

The best way to get round this is to convert the image using a package such as photoshop to turn the image to Black and white or to pixilate the image (like a newspaper print picture) so the laser is either on or off. This will prevent the laser markinging where it is not wanted.

If you have photoshop first convert the image to GrayScale which will get rid of colour information (IMAGE, MODE, GRAYSCALE).

Then convert to Black and White (IMAGE, MODE, GRAYSCALE).

Adjust the Brightnes and Contract (Image Adjustments Brightness and Contrast)

Then convert to Bitmap (Image Mode Bitmap) Set to 50% Threashhold.

This results in an image that is Black and White so the laser is on at full power where the picture is Black and off where white.

I will ask Admin to post some pictures using your sample and one from a good quality origional.

[Denford Admin]

As an example:

Original colour image:

Then convert to Black and White (IMAGE, MODE, GRAYSCALE)

Adjust the Brightness and Contrast (Image Adjustments Brightness and Contrast)

Then convert to Bitmap (Image Mode Bitmap) Set to 50% Threshhold.
This results in an image that is Black and White so the laser is on at full power where the picture is Black and off where white.

[Denford Admin]

Also, have a look at this thread:
http://denfordata.com/bb/viewtopic.php?p=869#869

It shows how LaserCAM or QuickCAM 2D Design can be used to modify colour images to create great looking contrast engravings

LaserCAM is now being supplied free with every Laser machine that we sell.

[AR]

doe's any picture for any matirial need to be hige contrst ?
where can i find some kind of manual, that will tell me how to edit my file
for specific matirial?

[Denford Admin]

You don't always have to have high contrast.
It all depends on the material your "etching / burning" and the image you have.

Most of the time you can simply print the full colour image and the versalaser driver will do a decent job of rastering onto the material.

Expermintation is the key - get a decent image editing program, eg Photoshop, CorelDraw / CorelPaint and use the tools in there to optimise the image for engraving - there are enough free tools such as the Gimp http://www.gimp.org/ to experiment with.
On most packages you can apply half-tone to an image (so it looks like a newspaper photo) - this gives great results on something like anodised aluminium - the image is still black (laser off) and white (laser on), but it preserves the different shades of the image
Other tools like edge detection can be used to clean up images of text / logos

Have fun

[casinoman1]

I got ugly horizontals lines all over my picture, and also outside of the picture area.
I see that ar have the Sam problem pleas send me what you find out what is the problem

email to dror42@hotmail.com


thanks

[Denford Admin]

Can you post a picture attachment of the results - I don't understand what you mean by horizontal lines outside the picture ?

If you are laser engraving a photo, then you normally need to clean up the picture first and alter the contrast.
You will always get "artefacts" when using lower quality compressed JPG images, which may be more visible when lasered.

[casinoman1]

HERE IS THE picture attachment of the results

[Denford Admin]

It seems like the laser is not switching off fully - looks like the laser tube is losing control over the output power.

Looking at the image, I would still try to create a black and white high contrast image to work on - all that fine grey detail will be asking a lot of the laser.

Nextly, I would try some different material settings on the same actual material - go for something very soft, which will use lower power settings, then try something harder (which should run the machine slower) and compare the results. Also try another (physically different) material with the correct settings and see what happens.

Other than that, I believe there are some tickle adjustments which may help - Martin will be able to advise on that.

If none of these help, then it could be your laser tube or control board has a fault

[casinoman1]

I contact versa laser and the are sending me CPU and HUB-USB I am going to try that we try to play whit the switch on the laser tube but its not working so we are going to try this part first I will send you my result the machine is new under warranty

[Denford Admin]

Thanks - it will be good for us all to see what the cause of this problem was if it happens to someone else.

[casinoman1]

go to viewtopic.php?t=324

and see that this happened to AR too