Erase Background in CorelDraw X4

[Richard McMahon]

Hi guys,
I am wondering if someone can steer me in the right direction with a problem I have.
I need to erase the background from my laser files and make it transparent so that I can engrave them bigger than 9" in size.
I am using the Solustan Linkmotion V2.56 software and the Leetro controller and apparently the software doesn't like "white" as the background and will chuck a fit if the job is too large and it faults to a VB-Script fault.
I have asked Solustan for the answer but they don't seem to want to mail me anymore and Corel sent me a phone tech support number but I have had no luck contacting them :-(
Can someone here offer some suggestions.
I use Photograv for a lot of my pictures but I have problems with that also with the white background.
Thanks in advance.
Richard.

[Rodne Gold]

What might help is to crop the picture to just include the elements being engraved , trying to "cut out" the background is going to be a mission and is going to take a long time.
If you use photograv and corel , what you can do is try to trace the PG output , its mainly black dots , however the trace file might also be too big and give you issues with the resolution. If you do trace , then fill the traces with black and then delete the trace outline to more or less get you back to what Photograv gives you without it being a raster file.

[John Barton]

When you say "white as the background" are you referring to vector files or bitmaps?

What I have done in Corel to eliminate the background on product images is to crop around them using the node tool. I have also made cropping masks to lay over the images and used the trim tool to eliminate everything I did not want.

To do this make a square larger than the image. Then make a shape, say a circle that should contain the image portion you want. Center the square and the circle. Choose the square first then the circle and trim the square. Then you will have a mask with a hole in it. Place this over your image and select the mask first and the image second and trim it. For easy editing of your mask make it transparent and then you can edit it as need to get the portion of the image you want.

I haven't found any other reliable way to get bitmaps into corel without the backgrounds. Once in a while I will have this dream that way back in Corel9 I was able to import transparent gifs and have them come in without the background. But since I can't do it now I think that that was some fantasy on my part.

[George M. Perzel]

Hi Guys;
Convert the image to a tiff with a transparent background.
Not sure how to do this in Photopaint but easy in Photoshop

Convert to grayscale, double click Background to make a copy, use Magic wand to remove background, save as tif file with transparent background.
Best regards;
George
LaserArts

[Richard McMahon]

Thanks for the replies guys.
I was wondering weather to convert to a .tiff file or not. I think .png can have a transparent background too.
I will try that and see where it gets me.
I thought the only way to do this properly was to convert the white bitmap background to transparent inside the program but I couldn't find any way of doing this.
I don't have Photoshop but my partner has Elements at her shop so I might give that a try as well.
Thanks for the interest guys.
:-)
warm regards
Richard.

[Mike Null]

Richard

If the image is a vector file you can ungroup it and delete the background.

If it is a bitmap you can use the shape tool to reduce the background as far as you like.

Or you can go to tutorials by Alex Galvez and see how he removes the background altogether.

There are a number of tutorials available here. http://www.youtube.com/watch?v=PBtpo5TfrZo

[Richard McMahon]

Thanks.
I have watched Alex's videos before and think they're great and even sent him a post a few months ago on this subject. Maybe he came through with my request.
I just tried something.
I loaded a .tiff file into Corel X4, process previously in PhotoGrav, of a nice steam train and then placed another .jpg of the same train behind the bitmap one and just off to the side to see if there is any transparency. I then, after a bit of blundering around, found out that if you select "no fill" in the properties tab on the side then the background white color is actually converted to transparent.
Could it really be this simple???
I will try the engraving out in a few days when I have some time in the shed.
This will really get me back on track if it works as good as it seems to on the screen right now.
Thanks for all the input.
Rich.
Below is a screen grab using MWsnap of the files before, after and also a closeup showing that it is indeed a transparent background.

[Martin Boekers]

[QUOTE=Richard McMahon;1451515]Thanks.
I then, after a bit of blundering around, found out that if you select "no fill" in the properties tab on the side then the background white color is actually converted to transparent.
Could it really be this simple???
QUOTE]

Amazing! after all these years and playing with this and then creating large TIFF file, it was as easy as that?!!!!

That was worth the admission alone. (opps I haven't paid admission yet, I guess this will be the time to buck up!. Keith, I'll get hold of you next week and get onboard.)


Marty

[Mike Null]

Here's another great graphics link. There are many tutorials here including getting rid of the white box.

http://www.unleash.com/articles/whitebox/

[Dan Hintz]

I need to erase the background from my laser files and make it transparent so that I can engrave them bigger than 9" in size.
If the problem is not enough memory due to file size, changing the background color to transparent will not likely resolve the issue. The filespace taken up by the transparent background is the same as the white background, it has simply changed "color"... consider it like changing the white to green.

If your driver does not transmit the transparent pixels to the laser, then yes, it may resolve the issue due to a lower amount of data stored in the laser's memory... but unless compression is involved I don't see that as being the case.

[Richard McMahon]

Thanks Mike, I have Foster's "Graphics Unleashed" DVD for Corel X3 but I couldn't find any reference to removing the background colour. It's worth buying the DVD if you haven't used Corel before as he has a pretty good teaching manner about him and you can get up to speed very quickly.

To Dan - : I have 4 Gig of memory on my 3.2 GigHz Pentium4 computer which should be ample for the table size I have. (50" x 32")

The nice people at Solustan sent me a mail a few months ago saying, among other things, that they " don't do white very well " and that Linkmotion doesn't process the transparent "colour" when printed. I hope this is the solution for me.
I will have a look at some of the links today while at the little woman's shop and see what I can get into trouble with. :-)

Thanks for all the help, everyone. It's been a big boost for my knowledge bank.

[Dan Hintz]

Richard,

I was talking about memory in the laser, not the computer. You don't mention what system you have in your signature, so I guessed it was one that contained memory on the motherboard and downloaded the entire file to the laser. If that's not the case, disregard my last response.

[John Barton]

Hi Guys;
Convert the image to a tiff with a transparent background.
Not sure how to do this in Photopaint but easy in Photoshop

Convert to grayscale, double click Background to make a copy, use Magic wand to remove background, save as tif file with transparent background.
Best regards;
George
LaserArts

And then you can bring this into coreldraw with a transparent background?

I have hundreds of images saved without backgrounds as tifs and gifs and I can't figure out how to import them without a background. I will die swearing that I did this once in 1998 :-)

If it's a raster file then I almost always have to use the node tool to trim the image so that the background is gone. I haven't tried this on my current laser to see what it accepts but on my ULS - if I remember right - it accepts the trimmed borders and engraves only the visible sections of the bitmap.

When I get to work later I will do a quick experiement to see how the laser handles a trimmed bitmap from CorelDraw vs a transparent background one.

[Richard McMahon]

Sorry Dan,
I have a home built 30 watt laser with a ULS laser tube running gecko 201 drives and a home built rotary attachment utilizing a 5 phase harmonic drive.
The Pentium computer controls the whole shebang.
I must get my profile updated soon to save any unnecessary comments and people wasting their valuable time trying to imagine what sort of setup I have.
My YouTube channel can be found here for a look at what I have.

http://www.youtube.com/user/baccus61

I think a few of you have already seen it before.
Rich.

[Mike Null]

Richard

That's awesome! Great work.

[Rodne Gold]

How does the "9" in size" fit into all this?

[Greg Bednar]

FWIW - I import the graphic into CorelDrawX5/Edit Bitmap (which throws me into CorelPhoto Paint)/Magic Wand/place cursor on background, press and hold mouse button, and then drag away the white background. Either crop in PhotoPaint or finish editing and crop in CorelDrawX5.

[George M. Perzel]

John;
After saving it as a tif with a transparent background, justy import it into Corel-so simple even a caveman can do it..........
Best regards;
George
LaserArts

[Richard McMahon]

Rodne, et al,
The 9 inch size is about the limit of the size I can currently engrave without the program crashing with a VB Script Error.
Even with the converted file with transparent background I can still only get to about 16" in size without it faulting.
Apparently the software designers have had people engrave out to about 50" but I'll be damned if I know how they can do that without having 50Gig of RAM.

My set up is about as basic as it comes with no excess programs running and only Corel Draw and Linkmotion loaded so I still can't figure out how they do it.
Vector cutting is very good and I can cut multiple files out to the table size of 52" x 30" so there isn't a problem there.

It's just Bitmap processing that has really always let me down and the team at Solustan keep saying I'm doing something wrong. There is only so many times I can read an instruction manual and rewire the controller and play with the INI string.

If I can cut an EXACT square or circle 12" in size it also figures that I can engrave a bitmap the exact size I have drawn it. I can't ! It is also shrunk in on the X axis. I have to expand the bitmap nearly 2/3 bigger along X so it will engrave the correct size or close to it.

This is not acceptable as I can't engrave a picture then cut it out with a square or circle surrounding it as it never comes out the right size.
But, I am doing something wrong, they say.
There is only 1 INI. string for the laser program so bitmaps should be the right size that I draw them. They're not!
Solustan still say I am doing something wrong but I can't see how. I know of other people who can't get the software to work but after paying $1,100 for it I want it to work and work flawlessly. It doesn't.

I wonder sometimes how some people can laser engrave large slabs of Granite bigger than 2 feet in size without having to do it in 5 passes/areas.

Geez. I do sound a bit grumpy but I have invested hours upon hours sitting at the table in the cold shed tweaking and rewiring etc etc to no avail and at Xmas time when I really needed support for the Xmas present rush, I had none.

I think it's time to change vendors!

Does anybody know how WINcnc laser works?

Rich.

[paul mott]

Hi Rich,

I don't think anybody is fully satisfied with Linkmotion. A couple of the guys on another forum, buildlog.net/forum/viewtopic.php?f=6&t=36 have now given up in favor of alternatives.
It must be so frustrating for the Linkmotion software writers who are so close yet not quite there.

Paul.

[Rodne Gold]

The file size is a function of it's PPI - pixels per inch- (NOT dpi) albeit PPI and DPI are sometimes wrongly exchanged.
At best your laser will probably only resolve 100-150 dots per inch on granite, so making your graphics file any bigger or engraving at any larger value will restrict the size , try this:
Engrave at 100-150 dpi or failing that , resample the graphic so that there are 150 pixels per inch or less. If scanning , scan at 100-150 PPI (dpi) IE reduce the resolution of the file.
A 50" graphic is viewed at quite a large distance , you can get away with ppi and dpi values of 75 or less for this.

[Richard McMahon]

I usually engrave a lot of mirrors and I set the dpi at 350 for my 2" focal length lens which turns out about the best dot size for the 12" mirrors without leaving a lot of small lines between each Y axis move. My spot size is about 0.004" which I am pretty happy with most of the time.
I fitted a 1" focal length lens yesterday but I am yet to find the exact distance from the lens holder to the job top. I will do this later on but I did a few test cuts and found I can cut about 20% faster with it compared to the 2" focal length lens. More power density is really helpful.
Now I need to find some old magnets thinner than the ones I already use because they won't pass under the lens holder.
I tried 300dpi on Granite before and found the resolution for the stone wasn't up to scratch and had to drop my dpi down to 120 which was still a bit blurry but acceptable considering the picture wasn't that great. I don't have a ready supply of tiles in the town but when I next travel I will pick some up and do some more tests. It's all fun if the machine doesn't let you down. :-)

Thanks for all the help.
SawMillCreek really is a great resource filled with caring people. Hard to find now-a-days.
Be well.
Rich.

[Dee Gallo]

Rich, I love the super thin earth magnets, since they hold like mad but are really thin, like 1/16" inch. You can get them in small sizes, like 1/2" to 1" or so and that's plenty to hold most things. Put a tape handle on on side to make it easier to remove by lifting straight up. You can buy them on-line from lots of vendors.

:) dee

ps - a cheap source of thin regular magnets is old shower curtains. They hold well and they are a nice size.

[Richard McMahon]

Thanks Dee.
I'll look around for some. I wasn't too sure about the Neo magnets though as I think they would be way too powerful and just a bit brittle for the chipboard I cut with them but I might look for some thin Alnico ones. I get the dropsies sometimes and I need stuff that's unbreakable. :-)