View Full Version : Problem with Lasering Mirrors

Scott Shepherd
03-10-2007, 12:19 PM
I picked up a couple small mirrors at craft stores over the last week. I took a photo I had and converted it to black and white in Elements and saved it as a JPEG as well as a TIFF. Engraved it on a small mirror and it looked pretty good. I was happy.

Took a larger photo and a larger mirror and did the same thing. Looked like crap. It had lines going about at a 45 degree angle that didn't etch at the same rate as the area around it. For instance, someone's face would have this pattern of lines running through it.

I personally took all the photos using a 10MB camera, so I know the photos are premium as far as the resolution.

So, I took the original photo I had good luck with, imported it into Corel, and did a mid-size mirror with it. Same problem as the large one. Same pattern of lines.

I'm perplexed at this point. My only guess is that it's something to do with importing the photo and then possibly resizing it a little in Corel, to make it fit the item, but that's only a guess. The lines, at no time, are visible on the photo.

Here's a photo of what I'm talking about. The "pattern" of lines running across this are NOT patterns in his clothes!

Any ideas on what I'm doing to cause this?

Dave Jones
03-10-2007, 12:28 PM
In elements are you converting it to a bitmap (pure black/white) or a grayscale?

If bitmap, then it is making a dot pattern (typically dither or halftone). If that is what you are doing you need to do the conversion so it has the exact resolution (dpi) that you will be lasering at and can not resize it in Corel.

If you are converting it to grayscale in Photoshop (and not making dot patterns by converting to bitmap), and then relying on the laser's printer driver to do the conversion to halftone or dither, then scaling in Corel shouldn't be a problem.

Scott Shepherd
03-10-2007, 1:05 PM
In Elements, it just says "Convert to Black and White", I think. I've left work now, so I can't look. I'll swing back by there some time this weekend and have a look.

I totally unfamiliar with Elements, so I could be doing it all wrong.

Gail LaPorte
03-10-2007, 1:44 PM
Hi I am new to lasering .I do a lot of mirror's i do them twice to get rid of the lines. ( Am hopeing someone tells me diffrent settings so I dont have to anymore )I dont do anything to a pic. un less i want the back ground out of it, I just import it and them send it to the laser at what ever size mirror i am doing.
I have a 40W
I do the pictures at 70-100 /DIP 500
Gail LaPorte

Scott Shepherd
03-10-2007, 2:16 PM
Hi Gail, do you run them twice at the same setting? Or once heavy and then once light?

The first few little ones I did (of the same photo) had no lines at all. However, all the photos I have resized inside of Corel have had the lines. But, I do not know if I used the same image each time, as I had saved the photo in JPG and TIFF, so I could have used JPEG on one and TIFF on the others.

I'll have to test it out and see if I can track it down. I have a feeling that it's more to do with the type of file I'm bringing into Corel, but it's only a guess.

I'm using a 45W at 600DPI, 45 Speed, 35 power. Am I way off on those settings?

Dave Jones
03-10-2007, 2:40 PM
I'm very familiar with Photoshop (full version) but not so much with Elements.

Besides "Convert to Black and White" is there also a "Convert to Grayscale"? If so then "Black and White" is the bitmap mode I mentioned.

Alternately, when you convert to black and white is it giving you any options, such as halftone or dither? If so, then again that is the same as the bitmap mode I mentioned.

And finally, if you zoom way in on the image after conversion do you see shades of gray in each pixel, or do you see a series of pure black and pure white dots?

Nancy Laird
03-10-2007, 2:42 PM
We were told my our guru NEVER to resize photos in Corel, but always to make them the size we want them in our photoshop program. Seems that resizing in Corel degrades the photo. You might try making sure that your photos are sized in your photo program, then import them into your Corel graphic, but don't resize them after you get them there. Try that and see how it does.


Larry Bratton
03-10-2007, 5:40 PM
I know from my studies so far that photos need to be 8bit greyscale. If your using CorelX3, you should have Corel Photopaint available to you. Open it up, bring your bitmap image into Photopaint, resample it to the size you want it, it should be 300dpi, then convert it to 8 bit greyscale. All the tools are there. Then save it and import it back into your design in Draw. You should be good to go then. :)

Gail LaPorte
03-10-2007, 5:47 PM
I just scan them at 300dpi and import them into what ever program is used to send to the laser. I use Laser Master 2 because thats what came with my laser. I have one posted in here just do a search for mirror you will see it there is a picture attached . With that one it was at night so I did not want a black background in it so i toook it out.
I laser them at 70 speed 100 power with the raster-ramp settings on.

Gail LaPorte
03-10-2007, 6:04 PM
If i did it right this is the picture outside at night. to engrave it the background out. After i engrave them I spray them black so you can see them.

Scott Shepherd
03-10-2007, 6:43 PM
Thanks Dave, Nancy, Gail, and Larry.

In Elements, on the convert to black and white, it's no options. Just one click and it's done. There is a way to do the grayscale that's in a different place, so I think you're right Dave. I'll give it a go from a different angle.

I had been messing with converting everything to 8 bit b/w and I called support, and they said "Why are you doing that?". I said "Ummm....because someone said to!", and they said "Well, you can stop because you don't need to- try it".

So, I did, and it worked :)

I'll also try sizing it correctly prior to importing it into Corel. Thanks for all the tips. Seems like I'm now armed with enough information to take another whack at it :)

Thanks all-

Larry Bratton
03-10-2007, 6:58 PM
Thanks Dave, Nancy, Gail, and Larry.

In Elements, on the convert to black and white, it's no options. Just one click and it's done. There is a way to do the grayscale that's in a different place, so I think you're right Dave. I'll give it a go from a different angle.

I had been messing with converting everything to 8 bit b/w and I called support, and they said "Why are you doing that?". I said "Ummm....because someone said to!", and they said "Well, you can stop because you don't need to- try it".

So, I did, and it worked :)

I'll also try sizing it correctly prior to importing it into Corel. Thanks for all the tips. Seems like I'm now armed with enough information to take another whack at it :)

Thanks all-

Scott; Wait a minute. Are you saying 8bit BLACK and WHITE or 8bit Greyscale? I am laboring under the assumption that conversion to 8 bit greyscale is a MUST to raster a photograph. Does this mean you sent it to the laser in color?:confused:

Scott Shepherd
03-10-2007, 8:40 PM
Does this mean you sent it to the laser in color?:confused:
Yup, sure did, burned a photograph from a color photo onto a piece of wood and it looked good on the wood.

I can't say it was right, or perfect, because the wood was just a scrap of wood I had to try it out. I didn't have anything else to try it on, but it looked good and you could clearly see all the detail of the photo.

Dave Jones
03-10-2007, 9:55 PM
There can be confusion in terms used here because many of us think of "Black and White" as in old black and white televisions, meaning grayscale and no color. But in paint programs there are 3 variations (actually more, but 3 basic ones.


Color images obviously have color. These can be 8 bit, 12 bit, 16 bit, 254 bit, or can use "indexed colors" and have anywhere from 2 to 24 bits.


================================================== =======

Grayscale has no color, but has shades of gray. Usually these are 8 bits (256 shades of gray) but could be different numbers of bits giving different numbers of shades of gray. Some people think of this as black and white, and maybe some programs call it that, but most major paint programs call this grayscale.


================================================== =====

Bitmap or Black & White. There are no shades of gray. This is a one bit image. Pure black and pure white. Shades of gray are simulated by making patterns of black and white dots or shapes. Some people think of images with shades of gray as being "Black & White" but most paint programs call single bit images Black & White. Photoshop (full version) tends to call then "Bitmap Mode". This can also be confusing because of Microsoft's file format .BMP or "bitmap" but that has no relation to how many bits, shades of gray or colors are in the image. That's just a file format name.


Dave Jones
03-10-2007, 10:04 PM
If you place a color or a grayscale image into Corel you should have no problem scaling it there before sending it to the laser, though there was some mention of a bug in (I think) Corel 9 where the photo needs to have a resolution divisable by 4 or there may be some lines created when lasering.

Most lasers won't care if you place a color or a grayscale image in Corel, since they will convert it to shades of gray anyway.

If you convert an image into 1 bit Black & White in PhotoPaint or Elements (aka "bitmap" mode in Full Photoshop), or convert an image via PhotoGrav, then you can not scale it once it is in Corel or you will end up with lines or patterns added to the image when it is engraved.

Larry Bratton
03-11-2007, 12:10 PM
Good info Dave. Thanks

Tom Cullen
03-11-2007, 1:20 PM
Just one other thing to keep in mind, I also have a 10 mega pixel camera and eventually realized that the camera although 10 megs actually saves the images in the camera or on the card at 72dpi, you need to change the dpi in a photographic program before doing any touch up work.

Scott Shepherd
03-12-2007, 11:28 AM
Okay, I'm back to work on this, this morning and having tried various things this weekend, I'm drawing a blank. The closer I thought I got to figuring it out, the futher away I actually got.

Here's exactly what I am doing. Keep in mind, I did two mirrors last week of the same image and had none of these issues (hence the mass confusion on my part).

1) I have a photograph. Color. I took the photo into Elements and didn't use the Convert to Black and White, but rather the "Convert to Grayscale" function (the background was removed from the photo at the same time).

2) I saved it as a JPEG and as a TIFF.

3) Open Corel V12, click on "Import File", and drag open the area/size for it to import as. In this test case, it's about 3" tall.

4) Picture looks perfect. Hit the mirror image button. Send to printer.

That's the technique I'm using. Not really complicated.

As a test, I imported the JPEG, the TIFF, and the original Color photo and did them all at the same time. All three have the lines. The TIFF is a little better than the JPEG or the Color.

When I look at the object properties, I see two Grayscale Bitmaps and one RGB Bitmap.

I could easily fault the photo but since I have two items I did of the same photo, then I'm assuming the photo is not the issue, or it wouldn't have worked on two previous items.

I saved the settings from the first mirror that worked, so I know I'm using the same S/P settings. I have bumped up and down, the S/P as it's running to try and see if it fixes it, but it doesn't.

I also gave up on this particular photo and tried three other ones, all from different sources. All of them did the same thing as well.

I'm obviously doing something wrong in procedure, or there's a bug in the driver or something.

Just went into Elements and resized the photo to 3" tall, which made the DPI go into the 1200DPI range. Ran that one, still had the lines. Not as pronounced, but they were still there.

Everything is being lasered at 600DPI on the print driver settings.

Did I miss trying anything anyone mentioned? If so, let me know and I'll give it a go.

I just know I'm doing something wrong, and it's simple.

Thanks in advance-

p.s. We'll be having a sale on mirrors starting right now. Of course, they are all etched with a baby photo on them, or various other photos, and they all have lines running through them :) I think we'll need a bigger office for the scrap if I can't get this solved soon!

Tom Cullen
03-12-2007, 12:04 PM
Hi Scott,
I think I know what your problem might be, lets start from the beginning. 1: open your JPEG or TIFF in elements, from here you can mess around with the brightness or contrast using the ENHANCE drop down on top. 2: go to the IMAGE drop down and choose SIZE, at this point change the DPI to 300... you wont really need more than this. In the same area change the image size in inches to what your final size in Coreal will be. remember to always keep the image the same size in Elements and Corel,before sending to the laser. 3: Go back to the IMAGE drop down list and select MODE, click on GRAYSCALE, from this point you will save the photo by going to FILE and SAVE AS. When the SAVE AS window appears you MUST pick the file FORMAT you want to save it in . In this case choose from the extension list BMP, also pick the location to save it in and to the right click the SAVE button. you should now get a window that gives you BMP OPTIONS, choose 8 bit and say OK. Now you have saved it as a genuine bit map. I forgot to ask if you use Photograv? I usually at this point run my bitmaps through that and then bring them into Corel and print ( laser). Hope this helps , just follow the instructions and you should be fine..works all the time for me and the same would apply to Granite Marble etc.

Scott Shepherd
03-12-2007, 12:23 PM
Thanks Tom, tried it exactly as you said and still has the same issue with the lines :(

Not using photograv.

Any other ideas?

Scott Shepherd
03-12-2007, 12:30 PM
Here's a link to the photo I'm using. It's a large image, and a large file, so it'll take a minute to load and then it'll resize itself in your browser (or so it should).


Dave Jones
03-12-2007, 12:42 PM
When you followed Tom's instructions, and then imported it into Corel, did you still drag to size it? If so, try importing it and simply click on the screen to place it. Do not drag to place and do not resize it after placing. Just click to place it at full size and then you can grab it and move it around for position, but not to scale it in any way. All the scaling should be done first in Photoshop.

Also, I don't remember what laser you have, but on my Epilog there is a setting on the advanced tab of the driver for "clipart" vs "photograph". If you have something similar be sure to select Photograph.

Scott Shepherd
03-12-2007, 12:46 PM
Yes Dave, I did exactly that. When I imported it, I simply hit the enter button and it imported it in, the size I exported it out of Elements as. I then grabbed it and put it where it needed to be. Didn't resize or mirror it.

I also tried saving it as an EPS file and they didn't do any better either.

Epilog 45W. I tried the clipart/photograph setting yesterday several times. Couldn't see any difference there either.

I've also tried different sources for the mirrors, so it's not tied to one manufacturer.

Mark Fitzmorris
03-12-2007, 1:14 PM
Scot I ran your photo thru Photograve see if that solves your problem.


Scott Shepherd
03-12-2007, 2:18 PM
Thanks Mark, no such luck there either. Still has the same lines going at about a 45 degree angle. Not as bad. Not at all on the face or dark parts, but in the background and on his white sleeve, it was just as normal, lines running through it.

That tells me we've ruled out the photo and it's getting more down to the laser.

Having tried about 20-25 different things now, I'm almost ready to throw in the towel.

Having said that, I did the image on a piece of AlumaMark and it did fine. No crazy 45 degree lines. Just seems to hate mirrors for some reason.

Thanks for the help. On a side note, I was so impressed with the detail of the PhotoGrav image, that it's now on the top of my list of things to buy :)

Dave Jones
03-12-2007, 4:24 PM
Couldn't see any difference there either.

That surprises me. The clipart setting will give a halftone look to the image, which is a much coarser pattern than the dither pattern given by setting it to photograph.

Since you said it doesn't happen with the Alumark, how about trying any other materials you have, such as a piece of wood or plain glass. I'm starting to wonder if it's something caused by the mirror itself.

Are you engraving the front of the mirror or engraving away the silver on the back?

Scott Shepherd
03-12-2007, 4:32 PM
Works fine on any other material. Did it on a piece of popular, I think, no issues at all. I'll try a piece of glass and report back.
It only seems to happen on the mirror, engraving it from the backside.

That's why I thought I might be doing something wrong.

Scott Shepherd
03-12-2007, 4:41 PM
Tried it on a piece of glass, same settings, not the first line anywhere. Dropped the power down some so the image wasn't just a mass blob etched on it, and still, no 45 degree lines.

Dave Jones
03-12-2007, 4:53 PM
Sounds like the problem is the mirror itself. Maybe those lines are varying thickness of the silver coating on the back.