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cwestwood
02-23-2007, 02:04 PM
I'm having a problem with some of my carvings. The edge of the carve areas are getting "pecked" by the bit on the pass or two before it actually plunges into the wood (see pics). Almost looks like it is trying to feather the edge of the carved areas although the feather setting is set to zero. The confusing part of it is that when I carve the exact same image in reverse (with the letters sticking out) it looks great. Both carvings were done using the exact same image, highest carve quality, bit optimization at best, and zero feather. I also notice that when the reverse of the image is carved, it still takes some wood out of the high areas so that the tops of the letters are actually a bit lower than the original wood surface. I am wondering if these two things are a result of the Y-axis being slightly out of calibration. Or is it something completely different? Any ideas? Thanks, Craig

HandTurnedMaple
02-23-2007, 02:26 PM
Did you import these images into Designer? Or did they come as patterns?

It may be that they are some extra pixels from the pic you imported (if you went that rout). When you import it, turn the image in the second screen and see if there are any "fibers" (as I call them) sticking out of the image.

Cliff
02-23-2007, 02:28 PM
What does the graphic it was created from look like? With 256 steps in carving just the slighest bit of difference can cause unexpected results. I've seen this in some of my pratice carvings and when I enlarged the graphic used to create the pattern noticed the shade differences. Either not totaly white or totaly black depending if I was running an inverted image. The machine is accurate to say the least when it comed to detail.

Cliff

cwestwood
02-23-2007, 03:05 PM
Images were created in Corel Draw as black and white images and exported as a jpg. Then imported into designer. I tried looking at the second screen during import and didn't see any thing that looked out of the ordinary, but then again, I couldn't zoom in to really see any irregularities. Why would one image be so clean and sharp, and the invert of it all chipped up on the edges? Craig

Cliff
02-23-2007, 04:23 PM
Not sure one is cleaner than the other. While one show the pecks at the top level around the edges the other is inverted so the reverse is at the base of the letters and not as noticeable but I believe they are still there. The image looks as if it was carved in mdf.

Cliff

cwestwood
02-23-2007, 05:14 PM
I see your point that the irregularities may be at the bottom of the carving and therefore less noticable. From looking at the carvings themselves however, I can't see any signs of these "irregularities" in the inverse carving - it's very clean. Yes it was in MDF. Same problem noticed when carving pine and oak, although less noticable (I think the grain of the wood tends to mask some of it). The artwork is "clean" as a jpg so if the problem is from the artwork, it would have to be as a result of the import process. When I zoom in on the image in Designer it looks good there too as best I can tell. Any other ideas?

BoardSilly
02-23-2007, 05:29 PM
Looks like pixalation occuring between the color used in the lines, letters and the background. This is a small but distinct bleeding from one color to another. Almost a 'shadowing' if you will. Decrease your color depth in the jpeg and see if it cleans up.

CallNeg151
02-23-2007, 05:35 PM
I see your point that the irregularities may be at the bottom of the carving and therefore less noticable. From looking at the carvings themselves however, I can't see any signs of these "irregularities" in the inverse carving - it's very clean. Yes it was in MDF. Same problem noticed when carving pine and oak, although less noticable (I think the grain of the wood tends to mask some of it). The artwork is "clean" as a jpg so if the problem is from the artwork, it would have to be as a result of the import process. When I zoom in on the image in Designer it looks good there too as best I can tell. Any other ideas?

A couple of ways to tell if it is the jpg. Try carving the image twice. Does it have the same problem in the same places? If so, you almost certainly have a jpg problem. Otherwise, try carving a small piece created completely in designer, using no imported images. A simple carved square with a raster letter would work. Look around the edges. If the carving is clean, you likely have a jpg issue.

It looks like you are having some issues around the edges of the letters and lines. That mostly resembles jpg artifacting. Keep in mind that a 1/256th difference in darkness between pixels can create an nick from the carving blade, but is likely invisible to the naked eye on the computer screen.

Unless your bit is wobbling, or the markings are inconsistent between carves and appear on items not incorporating jpgs, then you likely have a jpg compression artifact problem.

Good luck!

Rickrljones
02-24-2007, 08:43 AM
On my last carving, My CW machine started pecking on the flat surface of the carving... I was carving the Great Seal of the USA... It's a dished VA3D pattern... The only thing I did different was the carving height... I used .500 for depth and 350 for height... That was the only time my machine pecked at the carving...

BobHill
02-24-2007, 09:19 AM
Could you have set the carving quality to other than BEST?

Bob

Rickrljones
02-25-2007, 08:56 AM
I do all my carvings with the best quality it can perform...

cwestwood
02-25-2007, 08:21 PM
Looks like it was the graphics. After creating the images in Corel Draw, we (my accomplice and I) were exporting the image and saving it as a JPG. During that process we were using the default settings in Corel which was saving the image at a 300 dpi resolution. That 300dpi jpg was then imported into Designer. We changed the export jpg resolution (in Corel) to the highest allowable (2000dpi) and everything we have run so far looks great. I didn't mention earlier that we were also having a problem with the outline function not recognizing shapes very well. By that I mean when we would run the outline pattern tool on our image, what looked to us as solid lines or shapes would be broken into many different pieces. This was a problem because the outline around our carving was intended as a cut line, but since it was broken into many different pieces, Designer didn't see it as a continuous line and thus wouldn't allow us to do this. After the change in export resolution, this problem has resolved itself also. Thanks for the feedback folks. It got us reconsidering some things we had earlier dismissed. Craig

Jeff_Birt
02-25-2007, 08:25 PM
You might try saving it as a GIF or PNG both are lossless formats and would be a better choice (300 dpi would be fine too).

liquidguitars
02-26-2007, 01:29 AM
You might try saving it as a GIF or PNG both are lossless formats and would be a better choice (300 dpi would be fine too).

that's right Jpg will never work well, as it is a compressed format its good for small work but not so good for detail bump mapping.

*** I AWAYS use PNG or BMP for cleaner work. ***

Liq

Baron Richard
02-26-2007, 02:52 PM
I found that creating a JPEG from CorelDraw 12 tended to dither the edge of the transition to add visual appeal on the screen. To get around this I now export as PNG (Portable Network Graphics) file and don't get any dithing in the pattern. This also allows you to set a transparent color for the background so you can have an image without a border shape to deal with.

Hope this helps.

cwestwood
02-26-2007, 09:05 PM
Ok I'll try the PNG tomorrow. I'll let you know how that works for me. Thanks, Craig

BobHill
02-26-2007, 09:22 PM
Baron,

For some reason, I've found that CorelDraw just doesn't make the best JPEGs from it's vector images, so I make them into a PSD and then in PhotoShop do the JPEGs which are great. And, Liq, JPEGs really do work well (when initally compressed well in PhotoShop) especially since it's in 8bit grayscale mode, same as a GIF. The only advantage of a GIF is that of transfering a transparent background, but since Designer isn't a program that accepts transparency, it doesn't make any difference there. Remember that a GIF is also a compression algorythm (LZW) just as a JPEG. In RGB you'll see a lossy color effect, but not much so with 8bit grayscale, so when the file is exploded in Designer (or other programs) you get the full image once again.

Bob

Jeff_Birt
02-26-2007, 11:08 PM
Bob, I have found that Designer does understand the transparent background. Try the same image with and without. The one with a transparent background won't have a rectangular background.

liquidguitars
02-27-2007, 12:22 AM
Baron,

For some reason, I've found that CorelDraw just doesn't make the best JPEGs from it's vector images, so I make them into a PSD and then in PhotoShop do the JPEGs which are great. And, Liq, JPEGs really do work well (when initally compressed well in PhotoShop) especially since it's in 8bit grayscale mode, same as a GIF. The only advantage of a GIF is that of transfering a transparent background, but since Designer isn't a program that accepts transparency, it doesn't make any difference there. Remember that a GIF is also a compression algorythm (LZW) just as a JPEG. In RGB you'll see a lossy color effect, but not much so with 8bit grayscale, so when the file is exploded in Designer (or other programs) you get the full image once again.

Bob

Not with my rendering software. I find jpeg a no go I will keep to BMP for overall use, if I need 32 bit I run PNG.

not to say I do not love the little jpeg format...

BobHill
02-27-2007, 08:55 AM
Liq,

I've not heard of 32bit graphics, but in any case Designer can only use 8bit shades of gray (256 shades from white to black).

Jeff,

How in the world are you Importing a GIF into Designer for a PTN without the background except by doing an Action (Lower)? No matter what format with or without a transparent background in the format, I always get the rectangle (yellow border) in Inport and then the wood rectangle that has to have the background and transparent part Lowered to remove the background. If I leave the GIF with a white background or transparent background in PhotoShop, results in Designer Import are the same.

Bob

BobHill
02-27-2007, 09:32 AM
Jeff,

Here are my GIFs with a white background and with Transparent background and with white background ready Import to PTN

Bob

Jeff_Birt
02-27-2007, 10:04 AM
Bob, I'm not sure what we are doing diffrent. I've attached an image (.gif) that I saved with a transparent background with the import screen in Designer. (It looks like the new forum SW converts everything to .jpg!) I draw it in Corel Draw copied to Photo Paint then saved as a gif.

BobHill
02-27-2007, 05:34 PM
Jeff,

What's the black in your Import image? Is that background, like my white? Do you still have to Lower in the next step or Raise Action? What's the image from next to it, the Original? My original is a raster image clipart that I made into a transparent background in PhotoShop, then imported it into Designer.

Bob

Jeff_Birt
02-27-2007, 06:05 PM
Bob, when you import an image with a transparent backgroudn it shows up as black on the import screen (3d screen) in Designer. I did not need to rasie/lower it. The second image was the original gif but the forum SW converted it to jpg.

I created vector art in Corel Draw, slected the whole image adn copied it to the clipboard. I then pasted it as a new image into Photo Paint and saved it as a gif.

BobHill
02-27-2007, 06:29 PM
Strange, Jeff, but since Lower works just fine, no problem. I'll have to do some experimentation later on, I guess.

Bob