PhotoGrav Installation

[Shari Loveless]

HELP! Just got the PhotoGrav software. I cannot even get to step one to install it. When I put the cd in, a little info box pops up with the following:

C:\WINDOWS\SYSTEM32\AUTOEXEC.NET. The system file is not suitable for running MS-DOS and Microsoft Windows applications. Choose "Close" to terminate the application.

I put a call in to PhotoGrav, but no reply yet. Has anyone had this problem? I have installed a lot of software before, this is a new one on me. The computer is a Sony VAIO desktop.

Shari
Arizona

[Shari Loveless]

Please disregard my earlier note. Photograv faxed me some instructions. They worked. It is now loaded and ready to use. It seems a couple of other people had the same problem before me. A 16 bit autoexec install file was missing. All is well.;) Now all I have to do is find the time to try it out!
thanks guys,
Shari

[Keith Outten]

Shari,

Good luck with PhotoGrav, I think it is the second most popular software that engravers use. Corel Draw has to have the top spot :)

Don't forget to follow the instructions to the letter. Prepare your bitmap and size it before importing it into PhotoGrav. Never make changes after the photo is processed, import into Corel and print...

[Shari Loveless]

Thanks for the info. I am planning on trying it out today sometime. Will let you all know what I think of it. I am going through the manual and trying to learn all the options. :eek: I think I am a software junkie. If it makes my job faster and easier, I use it.

Shari

[Kevin Huffman]

Hello Guys/Gals,

I just got a copy of this software with one of the new machines we are testing out. It is a really good and easy program to use.

Just open PhotoGrav.
Open your picture. (has to be saved as a 8bit greyscale)
Load your parameters for the material you are using.
Hit auto process.
Save the engraved version of the file.
Imoprt it into your laser software.
Send the file to the laser.
And your DONE ! ! ! !
Perfect almost every single time.

I have been able to engrave photo's that we previous were unable to get to work because of this program.
I have am really impressed with how well it works.

[Jerry Allen]

Kevin, please share some of your settings for a Mercury 25, etc., with various materials.

If we use some sort of common baseline, everyone regardless of machine could interpolate and benefit from the input. I believe I've read that Epilogs and the newest Pinnacle machines run twice as fast as Mercurys do. That would mean if you recommended a speed setting of 50% on a Mercury, an Epilog user would use 25%, right?

[Rodne Gold]

Jerry , I don't think it's as simple as that , settings depend on a lot of things , like pulses per inch , beam quality , spot sizes , power density , how the machine ramps to speed , how the driver controls the laser , various brands of materials and substrates , how power varys over the table etc.
My Mercurys settings did not really translate in any linear fashion when we upgraded to explorers. (mercury uses synrad , the explorers use Coherent DEOS sources)They even vary between all my machines to some extent as even tho the rated power of all of them are the same , the measured power of my lasers vary by up to 10 watts. Im not sure of other mnfgrs , but with the GCc range , the rated wattage is the minimum and on one of our old 25 watt mercurys , the actual measured power was 37 watts.'

[Jerry Allen]

Thanks for the input , Rodne. As always good info that makes sense.

I still think there is some value in parameters from other machines. For instance, if I have no idea where to start and I read here that someone with a Mercury 60W used S50, P100, I might try starting with S25, P100. I don't expect miracles, and in a couple of cases it has me gotten closer the the needed setting faster. Even if the machine is totally different in every aspect, there is still some general info to be inferred from someone's discussion of their settings. It is even better if they specify details like machine type, DPI, material source, etc.

When you got your new machines and learned that there was no simple linear relationship , did you scrap all your previous data and start from scratch? I tend to think that there must have been some interpolation, at least for starters, based on your previous data after you had some experience with the new equipment.

By the way, how do you measure power?

[Rodne Gold]

We tried existing settings and extrapolating but it didnt work well , so reprofiled most of our settings from scratch. we were using a slightly higher powered and different make of source with different beam quality and characteristics. It was actually a good thing as we tried different ppi , dpi , power and speeds and found that lets say engraving at 25% speed and 50% power was actually better at some other arb setting of both parameters. Ie not better at 12% speed and 50%power (if extrpolating to a faster machine you must slow down the speed) but something like 20% speed and 80% power (just using those figs as an example).
What we did in terms of engraving is do tests starting out at what we thought was a good figure and then increasing speed by 10% (or decreasing) and then fine tuned a speed figure.
We then started right from our original and varied power to tune that and looked at many things like the smoothness of the engraving , its edges , depth , heat affected areas etc (a 10x loupe is invaluable for the laser engraver , it tells you just whats going on.) Once we got a combined figure which optimised the quality vs speed , we then varied dpi and ppi a bit just to see what happened. You have to keep notes in all this. Eventually you get what all laser engravers want , optimised quality at the fastest speed. Essentially you want to always try keep your speed to the max the material/laser/optics can handle cos in lasers time = money, so when testing always keep that in mind. Obviously one wants to do the best work so quality is important. We did similar with cutting , tho there PPI plays a big part as does air assist. Most ppl don't even bother with air assist settings , but these are vital for great edge finishes
The PPI is how many times the laser "drills"thru the substrate in an inch and is hugely influential in the cut. Too much and you get bad edges , heated zones , warpage etc and too little you get rough edges. Air assist is not only for flame prevention etc , it does a lot of things , it cools the cut , blows away melt thru the kerf (cut line) , clears debris and smoke etc round the work area and so forth. The pressure is pretty important as is the direction and the spot it aims at and the angle it hits. For example in acrylic you want it to blow away from the direction of cut , almost straight down the cut and close behind the beam , this ejects the melt , and cools the pex so you dont get a remelt , but too much pressure cools too quickly and then you dont get a nice polish etc. Its worth while adapting the air assist nozzle if you can. Be VERY careful with the mercury and air assist , the air assist pressurizes the lens chamber and this keeps rubbish out , but it also means you MUST use totally dry oil free air and that generally means traps. If oil and moisture are in the compressed air , they land up on the lens and you kill the coatings and burn the lens and power drops.
We plumbed in an extra valve and use various gasses thru the air assist to aid cutting , we use nitrogen with polycarbonate and papers and other substrates to stop burnt edges or edge discoloration and so forth.
All This might sound a little anal etc , but we found trial and error and getting things right has upped productivity and allowed us to do very diverse stuff and thus get more business in the industrial sector which is very very profitable and normally entails nice runs. Helps with all types of engraving and cutting in fact.
Laser power is measured with a power meter , we dont have one , but our supplier does and we often just loan it for a day when doing alignments etc. Once we get a power figure for that laser , we take 3mm pex and cut it and note the settings. (we always use 100% power and use speed to measure the difference)
Every few days we do a small test on a piece of 3mm at all 4 corners of the table and in the centre. This tells us if there has been a power drop or if at any point of the table power is dropping off and then we run the difference between the last figure and that thru our database for that machine and apply it as a correction factor. We keep an excell spread sheet with all the values put in and with testing the material we know that if there is a power drop whether to adjust just speed or both power and speed. All the operator does is punch in the test value and it recalculates all the settings for that machine which is typed into the driver or saved as a mer file
It really works well. We started it when we only had one mercury and we really benefitted from it.
We also investigated the properties of materials we worked with cos understanding them allows you more insight into a lasering strategy for that material. We tried the settings in the mercury manual at first and found most of them disasterous.
Regards
Rodney

[Jerry Allen]

As always a great and informative answer.

The Excel method sounds great. I already store my settings in Excel and will attempt to set the file up as you mentioned.

[Steve Spaulding]

LaserProUSA Dealer here.

Keep in mind that there are always variables to effect performance.

Original Power of the tube, for example a unit sold at 30 watts might perform at 34 to 36 watts.

Power source, clean electrical lines will allow for better performance for the tube. Line Conditioners are good for stabilizing the source, particularly for photographs.

Optics cleaned and aligned, etc.

Balance all these variables and the settings that are used for the original reference might actually be reletive to the specific machine.

The excel approach makes sense as it not only draws a specific guideline for your specific machine, but also can serve to monitor the changees that can signal a needed cleaning or maintenence item.

[Abdul Baseer Hai]

I got PhotoGrav software with my GCC Explorer package. It is awesome. I am still learning and would appreciate answers to the following:


How to define a specific colored material (wood) other than the choices given in the program.
Why is one prompted to save both the Simulated and Engraved files.
If only the engraved file is sent to the Laser, then what is the purpose of the other.
What is the exact sequence and method of creating and saving a BMP file from a scanned picture. (I am using Corel 12 and am not very comfortable with CorelTrace)
To get a true 3D output on an Explorer 50watt, what are the settings in the print driver. (On maple)
Thanks

ABH

[Rodne Gold]

Not sure about no 1 , I think you need to DL prameter sets or redefine them , we use one setting mainly for everything , the light wood one. (we invert if needed before the photograv processing)

2/3) Most likely cos you can print it or show it to a customer or compare it to the actual output - we never save the simulation.
4) When scanning you have to have the size you are outputting the pic in mind , scan at 300 dpi (pixels per inch actually) to play safe. If reducing the size , scan at less.
The scan resolution if using 300 dpi should be output size/input size x 300.
All you do is convert it to 8 bit greyscale using your raster editing program , resize it without interpolation and and save as a bmp. You have to have photopaint or some other raster package to edit the raster file if you want to go this route. Coreltrace is a tracing package and has no use in this workflow.
If you have no raster editing program , You would use Corel to export a vector file (like corel clipart) as a bmp and pick the greyscale 8 bit option , you can do the same with any scanned file. Make sure the orientation and size is the same as what you want to engrave. Problem with doing this is that you cannot edit the file at all as a raster image. There are tons of free programs like Irfanview (www.irfanview.com (http://www.irfanview.com)) that can raster edit anyway (irfanview is pretty potent)

5) Photograv will not allow 3d engraving as the file it sends is not greyscale at all. 3d settings depend on material etc and it's almost impossible to give a general formula. The depth of the deepest engraving is linked to max power and thus the material has to be able to handle it without getting burnt or having appreciable heat affected zones , so max power/speed has a limit and thus the deepest depth you can engrave has one too based on the laser and materials. On some stuff you might only achieve a very small difference between the deepest and shallowest engraving. DPI and PPI also play a part here.
Stategies to do 3d depend on the material you work in , and a lot of materials do not respond at all well to 3d work (like acrylics which tend to remelt to the surface of the engraved sections and leave a horrible lined and crumbly surface)
The best strategy is to do multiple passes at lower power levels with physical clean up between passes and then finally to do a polishing pass over the whole graphic. IE rather do 3 passes at 20% power and 50% speed whilst changing the focus point and or power settings between those passes and using a brush physically remove residue.then run a solid black pass over the whole engraved image at high speed and low power to try polish the surface of the 3d engraving. The problem with that is repositioning the engraved article and the fact that changing the focus point can change where the beam hits the surface , so misregistration on very small text etc is almost guaranteed , not such an issue on less detailed and bigger images.
3d engraving is generally best done on stuff like supawood and is very much a waste of time. A better pseudo 3d and a more successful engraving style is to rather do discrete multilevel engraving using colours to set depths. You dont need many levels (3-5) and can vary these to emphasise various elements in the drawing. You need a vector based file to do this as you would need to set various elements of the graphic to specific colours which is not really possible with a raster image.
A laser is not the correct tool for 3d (well its actually 2 1/2d) engraving , something like CnC engraver is much better to attain better surfaces and to control depths.