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Khalid Nazim
11-25-2012, 9:23 AM
I have an order to engrave the attached grayscale image on leather. Any suggestions on how to do it on a Shenhui using RDCAM or any other laser that uses RDCAM/Laserworks software? I would like to know if I can directly engrave the image on leather or would I need to prepare the image as a halftone image and then engrave.

Regards
KN
246344

Ross Moshinsky
11-25-2012, 9:48 AM
You're going to need to do some photo editing. The first step will be to do something with the background. That gray background will not work well. You're going to want to at least lighten it a few tones if the customer wants that grayish background.

After that, you're going to need to do some testing. I believe RDCAM has some sort of photo processing ability. It might work well. It might now. If it doesn't, you're going to have process the image in Corel using the Gold Method or something similar.

In order to get it right, you're going to need to do some testing. Think of it this way, the customer is paying you to learn. That way you can offer the service in the future and you'll know exactly what to do.

Rodne Gold
11-25-2012, 10:37 AM
It would be better to convert it in Corel using the "gold method" or photograv and import into RDCAM as a bitmap..you will have a bit more control. You can try use the RDCAM driver to do it , I never have , so can't tell you how it will turn out.

Lucy Lee
11-25-2012, 9:40 PM
Hi KN,
Yes,it is better to change it to bitmap ,then engraving , RDCAM should be same as laser cut 5.3,
choose photo---image size 10 resolution 500 p/i ok- mode grayscale discard color information? ok....................
hope this can help you

Best Regards
Lucy Lee


I have an order to engrave the attached grayscale image on leather. Any suggestions on how to do it on a Shenhui using RDCAM or any other laser that uses RDCAM/Laserworks software? I would like to know if I can directly engrave the image on leather or would I need to prepare the image as a halftone image and then engrave.

Regards
KN
246344

Joe Pelonio
11-25-2012, 10:22 PM
Leather is easy to mess up, since every piece is different. It's good to go to a leather supply and buy a bunch of samples of different colors, textures and thicknesses. Then when you get a job you can test it on something as similar as possible.

gary l roberts
11-25-2012, 11:08 PM
What is the COREL "Gold Method?" Sorry don't mean to hi-jack your post......

Dan Hintz
11-26-2012, 1:08 AM
What is the COREL "Gold Method?" Sorry don't mean to hi-jack your post......

In a much earlier post (years ago), Rodney outlined a basic method of preparing an image for engraving... it was later turned into a Corel macro by another member here, and it's now commonly referred to as "the Gold method". In a nutshell, it's a few steps to sharpen an image and (generally) increase its contrast before changing it to a single-bit image. What's on the screen will typically look over-processed, but that's often what's necessary to get the engraved image to look right.

walter hofmann
11-26-2012, 5:13 AM
Hi dan
I have try to find the macro for corel but I never was aible to can you give me thelink??
thanks
waltfl

Rodne Gold
11-26-2012, 5:39 AM
http://www.sawmillcreek.org/showthread.php?91076-Converting-programs-for-Engraving-Manual-Method-and-Adobe-Photoshop

Khalid Nazim
11-26-2012, 11:08 AM
Thanks everyone for your suggestions. The Gold Method did work for me and I took the following steps:

Steps in Corel PhotoPaint
1. Convert to Grayscale Change the size of the image - Image > Convert to Grayscale (8-bit)
2. Size image to the desired size and adjust DPI - Image > Resample >enter Width & Height + set resolution to 300+
3. Adjust Brightness/Contrast - Adjust > Brightness/Contrast/Intensity> for this image I increased contrast to +20
4. Unsharpen Image - Effects > Sharpen > Unsharp Mask > Percentage 500, Radius 4, Threshold 0, OK and then then one more time Unsharpen with Percentage 100, Radius 1 and Threshold 0
5 Convert to 1 Bit Image - Image > Convert to Black & White (1-Bit) > I selected Conversion Method as Stucki with Intensity at 100
6. Save As BMP image

Steps in RDCAM
7. Start RDCAM and Import Image.
8. Engraved it at 500mm/sec at 20% power, resolution set at 0.6

The image attached here is engraving on Vegetable Tanned Leather. I am going to stain it in Tan. This is for journal cover.

Regards
KN

246416

gary l roberts
11-26-2012, 5:34 PM
Thanks for the info

walter hofmann
11-27-2012, 6:03 AM
Hi rodne
thanks for the link but I cpould not find a macro of the " gold methode" for corel photopaint . is there one??

Mike Null
11-27-2012, 6:49 AM
Khalid

I have better luck with the finish if I wax the leather before engraving. I use a neutral wax like Johnson's paste wax then engrave, clean gently and wax again then buff.

Khalid Nazim
11-28-2012, 9:30 AM
Mike, do you use the standard Johnson's paste wax for wood on leather or is there a special paste wax for leather?

I stained and finished the cover see image below. Note: The yellow text is just to cover the name on the cover and its not the engraving :)
246586

Mike Null
11-28-2012, 9:55 AM
Khalid

I use the floor wax. Minwax makes one too. I have found that I can clean engraving residue with a light rubbing with diluted cleaner such as Mr. Clean.

Your work looks very, very good.

Balsanu Gabi
11-28-2012, 1:42 PM
Hi Khalid,

I try to follow your instruction's , but I receive different results. Basically what happened was related with the size of the image imported in RDCAM. I set the iamge at 150mm by whatever the maintain aspect ratio put. When I imported in RDCAM the image has 1041.753mm by another value. What I am doing wrong?

Thank you
Gabi

Khalid Nazim
11-28-2012, 4:22 PM
Hi Gabi,

Just make sure that the size of your image in Photopaint is not in centimeters or in any other measurement type other than mm. Check that out first.

Regards
Khalid

Balsanu Gabi
11-29-2012, 5:51 AM
Hi Khalid,

I try everything I think of but same results. The image imported in RDCAM is bigger than image exported from Photopaint. I don.t know what else to do. I try gold method same... Can you post a photo with the image already converted with your method (an before and after will be awesome)

Thank you
Gabi

Balsanu Gabi
11-30-2012, 7:20 AM
Hi Khalid,

I check and everything is in the same units. Still, same results. I try Rodne's gold method same. I think it is related with the way how RDCAM import the .bmp files. Can you post a picture of that photo vefore and after the process?

Thank you
Gabi

Guy Hilliard
11-30-2012, 9:54 PM
Check that the resolution of the image (DPI) in RDCAM is the same as it was in the processed image coming out of Corel. It sounds like the resolution in RDCAM is coarser (lower DPI) than the image that was exported from Corel.

Khalid Nazim
12-01-2012, 12:09 AM
Here you go. Before and after image attached here.246760246761

Ross Moshinsky
12-01-2012, 12:51 AM
Check that the resolution of the image (DPI) in RDCAM is the same as it was in the processed image coming out of Corel. It sounds like the resolution in RDCAM is coarser (lower DPI) than the image that was exported from Corel.

This is exactly what's happening. RDCAM probably runs at a native 72 or 90 dpi. A lot of programs automatically scale an image if its 300dpi to work with screen resolution but RDCAM obviously doesn't. Just take the image and scale it down to the side you want. It's the exact same thing.

Balsanu Gabi
12-01-2012, 3:29 AM
Do I need to scale the processed image in RDCAM? The reason for asking this is related with somr previous posts about not touching the image after was in the "laser engraving" state

Ross Moshinsky
12-01-2012, 8:09 AM
Do I need to scale the processed image in RDCAM? The reason for asking this is related with somr previous posts about not touching the image after was in the "laser engraving" state

Corel/Illustrator automatically look at the image's DPI and scale it. RDCAM doesn't. The monitor doesn't know DPI. It knows resolution. Scale it exactly the same size as when you did your conversion and you'll be fine.

Balsanu Gabi
12-02-2012, 4:11 AM
Thank you for explanstion. I will try that.

Gabi