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Mark Ward
09-06-2017, 5:40 AM
Whenever I copy for example a JPG or Vector and then paste into Coreldraw the image clarity goes and it becomes pixalated. Even then when I have to convert with the trace Bitmap tool to High Quality image lots of the detail can be lost depending on the image.
Is there a way of copying and pasting a jpeg or Vector image that I'm being really stupid and getting wrong so the sharpness of the image remains or should i be using Corel PhotoPaint for this process first?
An example image: https://static.comicvine.com/uploads/scale_small/11114/111142403/3673352-batman+-+the+man+who+laughs+-+page+00.jpg
Looks great in the browser but not as sharp in coreldraw.

Mike Null
09-06-2017, 7:49 AM
Mark

That image is a 72 dpi image. In other words, a very low resolution image and generally not suitable for much besides the internet. Even so, you may get better results when using trace if you try using outline trace-line art.

The photo is a straight trace (image on the right) with no re-touching. If you want a perfect vector then I think you're in for a lot of drawing. We would need to know what you intend to do with the image in order to advise whether PhotoPaint or CD should be used to edit the image.

Robert Bonenfant
09-06-2017, 8:18 AM
I agree with Mikes response,

You want to look for higher resolution pictures - You can find them on google, most likely you copied and pasted a thumb print image (They use these as place holders so the large image doesn't have to load) If you click on the image on google the base picture should be higher quality (The pictures source - Normally a secondary website from google). There is also a option on google to set minimum picture quality, also when working in corel draw try not to copy and paste images, Try to import them into the program - Copy and paste can cause trouble on advance work.

Kev Williams
09-06-2017, 12:05 PM
There is a quick and easy fix for pixelated photos in Corel-- click on: BITMAPS/RESAMPLE-- then up the resolution.

this is a 72dpi graphic as opens in Corel on the left. The right I changed the resolution from 72 to 1000, much better, and tracing the high res version will give you much better results too...367388

note the resample does work better the larger the original is-

Joseph Shawa
09-06-2017, 12:15 PM
It does work better but only to a limit unknown to me. CD will reduce the bitmap before tracing it even when set to the highest quality. I also set my smoothing to 1 so that I don't get too soft of corners.

Ross Moshinsky
09-06-2017, 2:17 PM
DPI is nothing more than a scaler in the digital world. It only exists in the physical world.

When trying to figure out if an image is of a good quality, you look at the resolution & the actual quality. That image "fails" the resolution test as it's only 457px × 640px. It might be adequate for engraving something small but even then, it's just asking for problems due to the relative complexity of the image.

Kev Williams
09-06-2017, 3:13 PM
Any complicated tracing I do in Casmate, which really likes it when I resample with Corel to smooth the pixels down. Since I don't do colors, I use Corel PhotoPaint to remove colors, works very well.

I rarely use Corel's trace because it's ridiculously frustrating, nothing I love more than when it sharpens round corners, rounds off sharp corners, and deletes graphic segments just when the result almost suits me... IMO it's almost completely useless. The ONLY time I use it is if a customer supplies a large, decent black/white graphic via email that 'quick trace' will work on. And raising the res on them does help.

Why I don't use Corel-trace: I took Mike's pic, left side original, copied it into CPaint, removed the colors, adjusted the grays left, saved it as a tif, imported into Casmate, traced it, and the only editing I did was to remove clutter above the cards, and made Batman's eyes bigger. Back into Corel where I engraved it onto a small piece of white Rowmark with the LS900. From start to engraved plate took less than 10 minutes. Not possible (for me) to get results like this from 'trace' at all, let alone so quick...
367390

Anyone with the patience to endure working with Corel's Trace has my utmost respect! :)

Mike Null
09-06-2017, 4:33 PM
Kev
In my opinion, the one click trace image I did with CD is better than your Casmate image. I just did the one click version so less than a minute was all the time it took. I am a fan of Trace and use it often. Some images are near perfect with the one click trace, others, such as this one require some more work.

Using resampling such as you suggested is a good idea also.

Mark Ward
09-07-2017, 5:31 AM
Thanks for all the replies guys! I'll give them a proper read over and try out what has been suggested. Good tip on checking the DPI of the original image too, something I'd not even thought of!

Ian Stewart-Koster
09-08-2017, 10:00 PM
I think the answer your problem is right in your first sentence: "copy... and paste..." [*shudder!*]

As mentioned you're getting a low-res screen shot @ 72 ppi resolution. That's crummy.

The only correct way to get a picture with ALL its detail into Corel is to use the File>Import command.

You can then trace or do what you wish with it, but you'll have it at the original resolution that way.
You must use the 'resample' option,too, rather than the resizing 'handles' if you wish to keep resolution as you enlarge somethng - unless it is not important.


Hope that helps.

Kev Williams
09-09-2017, 12:37 AM
I think the answer your problem is right in your first sentence: "copy... and paste..." [*shudder!*]

As mentioned you're getting a low-res screen shot @ 72 ppi resolution. That's crummy.

The only correct way to get a picture with ALL its detail into Corel is to use the File>Import command.


Try as I might, everything bitmap comes in to Corel-- at least MY Corel- at 72dpi, regardless...

1- click 'import'-- (look close, lol)
367552

choose a pic on my computer- this is 10 mpxl pic of our mutt--
367553

click it in--
367554

I imported it, not copy/paste, it's 53.778" wide x 30.222" tall,
3,872 x 2,176 pixels, which is definitely all it's detail, and--
- it's 72 dpi...
367555

No matter what pic or bitmap I copy/paste or import, it's ALWAYS 72 dpi...

Mike Null
09-09-2017, 9:39 AM
Kev

Can't lay claim to expertise here but if I import from my photo file I also get 72 dpi images but if I've saved an image to a Corel folder at the original resolution I seem to be able to import it as is in Corel. But, trace will not work if the image is above a certain size and it will ask if you want an auto reduction in order to trace the image. Trace does not reduce the dpi of your original image except for the purpose of the trace.

The bitmap below is a 300 dpi image from the customer. I used trace with just one click to get the vector image shown. The image needs a little work but I think it's pretty good.

367565

Glen Monaghan
09-09-2017, 11:23 AM
Your Quick Trace results may differ depending on your CorelDraw settings... If you go to Tools, select Customization, and look in the Workspace section under PowerTRACE, you'll find options that determine how Quick Trace functions. Mine is set to trace using Last Used (whatever method I last chose manually) and highest quality. While verifying this, I also discovered why one trace option (merging colors) wasn't working quite right: I had the tool set to average merging colors, but I wanted merge to first selected color! There is probably a setting somewhere that to change the default dpi for pasted images, because mine defaults to 96 dpi compared with the 72 dpi many people have noted.

I think the point about dpi vs total pixels has been made at least once, but I'll reiterate that dpi is not particularly important in this context. If you have AxB pixels, it doesn't matter what the dpi is; you'll get the same trace results whether it's 72 or 300 dpi. What matters is how many pixels you have to work with. Mike's original elephant image may have been 300 dpi but, if it only measured (approximately) 865 by 270 pixels (which is about the size of the "300 dpi" example shown above), then any version of CorelDraw trace would have produced a much worse result than he shows. Upping the pixel count to 1730x540 (doubling the image dimensions while quadrupling the number of pixels) significantly improves the trace results. However, attempting to further improve CD's trace by continuing to increase the pixels quickly hits a limit and CD will start to ask if you want to reduce the bitmap before tracing. Up to a point, you can refuse and wait longer for the full image to be traced, but the results typically aren't noticeably better. And, before you can get enough additional pixels to improve the (full image) trace results significantly, CD changes its popup so that, instead of allowing you to continue with full resolution and longer processing time, your only option is reduce resolution or cancel.

Depending on the image and your needs, you might find that you can get better/acceptable results more quickly by breaking apart a large bitmap (that would otherwise have to be reduced), separately tracing the parts of the image, and then combining the results. In Mike's case, he might split the image to trace each elephant and the central region separately (3 sections) to pick up the fine details better and avoid a lot of manual tweaking. Also, I find that text (especially curved, like Bullet Safaris) often traces poorly and is particularly problematic to tweak manually. If the initial trace of text is unacceptable (and I know/can quickly find the font or a close approximation), I find it much faster and better to throw away the traced text and replace it by retyping the text and fitting that to a purpose-made curve.

Mike Null
09-09-2017, 12:05 PM
Glen

Thanks for that explanation. I have always been of the high res gets better traces school so it's good to have your info.

David Sharp02
09-18-2017, 9:10 AM
Try as I might, everything bitmap comes in to Corel-- at least MY Corel- at 72dpi, regardless...
I imported it, not copy/paste, it's 53.778" wide x 30.222" tall,
3,872 x 2,176 pixels, which is definitely all it's detail, and--
- it's 72 dpi...
367555

No matter what pic or bitmap I copy/paste or import, it's ALWAYS 72 dpi...
Just change the DPI to 600 or whatever, and then click the checkbox "Maintain Original Size".

This will keep the actual pixel data the same and simply mark the image as a higher resolution. If you look, you'll see that originally, the image is 54" wide. If you bump the DPI to 600 it will cut that down to around 6.5". I'm still learning to use my laser engraver, but I've been told that you want the DPI to be such that the pixels are large enough that your laser's minimum spot size can accurately render the pixels, ideally without any periodic resonance. So if the image is still too large at the DPI suitable for you machine, you may need to resample again to cut the size of the image down fit your machine.

Dave

Kev Williams
09-18-2017, 7:45 PM
I know about upping the dpi by just entering it, I have one customer who insists on sending me thumbnails sized pics, like 75 x 75 pixels--I just engrave them direct in halftone, and the engraving area for them is only about 10x10mm, and just raising the DPI does help!

Before I go further, just want to reiterate that 99% of my work is 2 colors- actually, more accurately would be ONE color, BLACK, since the other color is "nothing". So while I give props to PowerTRACE for tracing colors, that doesn't help me much, especially since I just cannot get a satisfactory simple black outline trace unless the original is pristine and large.

This is from an actual job last week. It's not pristine OR large. My customer sends me sayings and names and such to put on SIC cups. This is one from last week, a name and a date. I chopped off most of the name for this test...

First, I copied this into Corel directly from the email.
Just to make a liar out of me, note the DPI. I haven't touched it!
Also note the size, pretty small at 2.53" across...
368129

So I throw it into Trace, and proceed to try and get a decent result.
I tried a few options but went 'line art', and spent quite a bit of time moving sliders trying to get it to look good.
Every time I moved a slider I had to go into 'settings' and change the colors back to 2. Irritating...
But this was almost the best I could muster. I did get it a little better but not much...
If I went more detail, the hard lines got harder. Less and the holes would fill in.
368130
--Changing smoothing would make some areas smoother but others flatter...?? Why can't it just outline what it sees?

So I copied it into Corel Paint, changed it to grayscale, and exported it as a TIF, then imported into Casmate...
368131

This is a zoom-in... note it's major pixelated, and I've done nothing to help that, it's still as-is from the email.
368132

So I clicked "vectorize", and in less than one second- no kidding- done! --check out the lines, very smooth, no choppy edges...
Casmate doesn't try to guess at corners or curves or smoothing or detail, it just simply outlines dark, and does a great job.
Now, Casmate DOES have a secondary option called 'enhanced corners', where I can choose smoothing and detail settings, just like Trace-
and guess what? The results are a lot like Trace, rounded corners and squared off round edges. Nah, I'll just use one click and done :)
368133

Below is a screenshot of the Corel job in the link below, with the original emailed image on top, middle is Corel Trace's version, bottom is Casmate.
I removed the name pieces from the vectors...
368134
For simple black/white tracing from user file to laser, there's no contest. I did zero editing to any of this, other than the grayscale change necessary for Casmate.
Oh, and to pull out all the second holes from the Trace version. All inner holes were doubled up...
The Corel file below is a version 10, feel free to open and check it all out. If someone can figure out how to make a decent Corel Trace from the original, I'd love to know how! While I love Casmate, it's just another step I'd just as soon avoid if I can get Trace to work!

368135



.

Mike Null
09-18-2017, 11:18 PM
Kev
I'm working with my Mac with Parallels so this is my first attempt at using it for such an exercise. First, your file that you posted is not what you used for the trace. Therefore I can't demonstrate Trace, apples to apples so to speak.

With a simple black and white I use quick trace--just one click.

As an aside, I thought I was being very clever in buying this MacBook and Parallels, Win 10, and X7. I was far less than clever.

Kev Williams
09-19-2017, 12:55 AM
Kev
I'm working with my Mac with Parallels so this is my first attempt at using it for such an exercise. First, your file that you posted is not what you used for the trace.
oh, but it is!! In the Corel file, the very top is the image I traced, the other 2 are the results...

this is the wireframe view-
368155

Mike Null
09-19-2017, 8:14 AM
Kev

I'm now on my working pc. I stand corrected!

My quick trace with one click appears to be as sharp as yours but the inner holes have to be edited. That may be more time consuming than your process.