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Daniel Muller
02-26-2009, 9:42 AM
I am new to photograve and I have attached a photo of what i have done and the pic I used. what else can i do to get this photo right. I have read the user guide over and over and it doesn't seem like i am getting anywhere. Using photograv 3.0 epilog helix 24/ 40 watt

material black granite
power 40
speed 100

Steve Clarkson
02-26-2009, 9:52 AM
Dan,

Have you tried one without photograv? Try just Stucki.

Daniel Muller
02-26-2009, 10:07 AM
trying it now. i figured I gave up my first born for this program and would like to get it to work for me.

Tim Bateson
02-26-2009, 10:59 AM
Daniel, I no longer user PhotoGrav for anything. Try your driver's dithering options.

Steve Clarkson
02-26-2009, 11:19 AM
Tim and Frank are converting me to anti-photograv.......

Martin Boekers
02-26-2009, 1:50 PM
Have you tried it on black marble?

It's a bit hard to see with image size and the flakes in the granite.

Granite is tough to work with, I cringe when a client suggests it!

Marty

Larry Bratton
02-26-2009, 4:55 PM
I am new to photograve and I have attached a photo of what i have done and the pic I used. what else can i do to get this photo right. I have read the user guide over and over and it doesn't seem like i am getting anywhere. Using photograv 3.0 epilog helix 24/ 40 watt

material black granite
power 40
speed 100
Daniel:
First of all, you need to make the background black. Anytime you do anything on black material you need to do that as Photograve will invert it. I prefer to take the photo I am using into Photoshop, tweak it and convert it to Greyscale, you can use Corel Photopaint if you don't have PS. You need to begin with a photo of at least 300dpi. Engrave it at 250-300. After you have submitted it to Photograv, use the Interactive feature to tweak it a little more. Photograv will report a recommended power and speed setting to you based on the parameters you entered for your laser which are higher than what I do. I use those settings you used, maybe 50 power and usually get pretty good results. Also remember that granite is a natural material and results may not be consistent from piece to piece.

Daniel Muller
02-26-2009, 9:16 PM
Larry,
Thanks I have tried both doing it without photograv and with photograv but not tweeking it first then photograv. I understand the natural material but I am just running small images to get it down first so I am utilizing a few different pieces. I will give it another shot.
Dan

Larry Bratton
02-26-2009, 10:02 PM
Larry,
Thanks I have tried both doing it without photograv and with photograv but not tweeking it first then photograv. I understand the natural material but I am just running small images to get it down first so I am utilizing a few different pieces. I will give it another shot.
Dan
Did you make the background black in the original photo? To explain what happens, after you have processed your photo in Photograv, save the engraving. Photograv will designate it with a ENG in the name. Then re-open that file with Photograv and you will see that your dog is now a dithered image on a white background. The laser fires on those black pixels and that is a simplified version of what's going on there and why you need to work on that background. ( I realize the dog is black, but do it anyway)

Also, Daniel, when you re-save that file, save is as a bmp or a tiff etc. Each time you save the jpg format you lose quality due to compression and that jpgs by nature are "lossy" files. Be sure you start with a good high resolution photo..that is imperative. Your photo looks OK in here, but it would at that size. What size are you trying to engrave? If you have a 72dpi file and then try and make it into a bigger size by stretching it, it's not going to work. Be sure also that once you get it into Corel, don't do anything except to move it in to position..no resizing etc.

Daniel Muller
02-26-2009, 10:53 PM
I am still giving the photograv the benefit of the doubt but I am just struggling getting this to work for me. Attached is the granite piece I just finish and didn't use photograve.

Frank Corker
02-27-2009, 8:41 AM
Daniel, that result is as good as you are likely to get from the picture that you posted. The Epilog drivers, as I am finding more and more, are able to turn out good results from photos without the need for photograv (Epilog rocks!!), especially when the backgrounds are black.

You have a few things working against you that I can see. Firstly your image should have been sharpened (I would recommend to anyone using Focus Magic). I don't believe that you did that. Your image could have been enhanced by removiing the background, but the oval vignette has been quite successful. The granite that you are using is not absolute black, the small speckles that you see deflect the laser light and so the surface is not as even as some that you have seen.

At the end of the day, you can only get a good result from a good image.

Dan Hintz
02-27-2009, 9:15 AM
Daniel,

I would be relatively happy with that engraving given the picture you started with. As Frank said, I would have sharpened it a bit more and faded the edges of the vignette a good 20 pixels or so, but nice enough.

I chose to stay away from PhotoGrav, as well, being a glutton for punishment (and a damn stubborn engineer, to boot). After some sharpening and contrast adjustment in Paint, I simply select the Dither option in my print driver (I keep meaning to ask tech support what algorithm they use as it's not listed). It took me 12 2"x3" images on a single granite tile and one extra 6"x6" test tile before etching an image that I was happy with. The 6"x6" was a huge leap in quality from the smaller ones, and my second 6x6 was spot on.

Practice practice practice...

James Stokes
02-27-2009, 9:29 AM
You do know that you can take your test piece and paint it with black spray paint and re-use it do you not. Also I generally run my tests on porcelain tiles painted black. If you buy the porcelain tile you can find 12 x 12 for around 89 cents.

Daniel Muller
02-27-2009, 9:32 AM
Frank & Dan

Thanks for the encouragement and the suggestions. I don't think I sharpened the image but even getting to this point from what i started at was a relief. I will keep plugging along and sure i will be hitting some of you up for more suggestions.
Thanks Dan

Dan Hintz
02-27-2009, 9:45 AM
James,

Porcelain tile doesn't have the same blast pattern as granite due to the flecking. Now that I've (somewhat) mastered granite, I feel confident anything I do in tile will be acceptable right off the bat.

Daniel Muller
02-27-2009, 9:55 AM
James,
did not know that. this is still new to me so i am learning but quickly with the help of all of you.
Dan

Larry Bratton
02-27-2009, 10:52 AM
James,
did not know that. this is still new to me so i am learning but quickly with the help of all of you.
Dan
Good job Dan!
Another trick that some people use to make the engraving whiter..(don't ask why) is to spray the piece and wipe it down with Armorall before lasering.
I haven't had occasion to use the Epilog driver for dithering, so I won't make a comment, but if Frank says it, I believe it. I'm going to try it.