Saving Lens Info with file

Am I correct in assuming that LB does not save the lens information in the LBRN file? for example if I setup a job to use the 70mm lens on my galvo, save it, then reopen it a month later to run more pieces the file will not be set for a 70mm lens, is this correct or am I doing something wrong?

The system “doesn’t know” which lense you use but with a little bit of needlework you can easily save these infos with your project.

With a fiber, the lens information is in the device settings. If you create a device, load the proper configuration file for the lens and it will load the lens information on device selection.


I have a device named F254-fiber and F420-fiber, one for the F254 and one for the F420…

Either import the correct markcfg7 that was sent with the machine when Lightburn asks for it or after it’s configured the cor file…

Make sense?

:smile_cat:

Thanks for this, I forgot about the notes feature. But are you telling me that is I set a file up with my 70mm lens profile, that profile doesn;t get saved with the actual file?

A co2 doesn’t need to know, but with a fiber it has to know… at least Lightburn needs to know…

A different lens on a fiber requires computation to ensure a surface speeds… Different distance to the material will change the scan speed at the material.

:smile_cat:

I have no Galvo Laser and not Lightburn version for Galvo machines but assume that just like CO2 Laser Machines and Diode Laser machines, only the process values are stored in the projects. In Machine Setup you have determined how your machine is built x, yog z and how fast it runs and similar parameter. But neither your laser machine or lightburn “knows” what your focus is set for, what a lense you have fitted or what material you work with, all variables have to be written down, either in the material library or as a note for the project. I have no idea how others do but for me it works up this way.
I’m pretty sure you can and should make a machine profile with the different parameter for the lens you have, it will be the easiest and you avoid mistakes.- (Unless the difference is minor problematic and can be adjusted along the way, this is what I do when I am rarely changing the lens in my machine.)

On a gantry type, there isn’t much in real technical problems in their operation and use. F type lenses or any lens for a galvo head is a bit of a different animal.

Somebody has to know, the machine or the software.

The F lenses are a short abbreviation for flat field of focus. Meaning from the laser origin point, in the galvo head to the materials surface changes distance as it scans across the material. There is a change in surface speed occurring also.

As in post 5. Unlike a gantry type machine, if you want mm/s on the material, you have to know the distance. This also determines actual work area. This change is handled, for focus with an F type lens, but the galvos have to change speeds to correct the actual surface speed.

Each lens is uniquely different. All F lens have inherent variations in manufacturing, so each lens carries along with it a set of correction values. These are done by the manufacture for each machine/lens. If you purchase a new lens you have to set it up. It’s considered unique to each lens/machine combination. These imperfections are in the lens. The lens probably seats (rotationally) a bit differently in machine A compared to machine B, the corrections need to be re-calculated.

How Lightburn does it, I don’t know. I would think it does all these adjustments when it generates the code. How much the controller itself handles things is also unknown to me.

Bought my machine with one lens. I have added three more, what a drag to generate the data to correct them.

All the demo videos I’ve seen create a different device for each lens. EZCad videos just duplicate the directory and rename it. Then modify or correct that entries lens.

Create a new device and also create a new library for that lens… You will find they might be in the ballpark, but then again, may not work at all.

It’s surprising to find out how much your settings change when you change lenses.

As the lens get shorter the spot size gets smaller…

:smile_cat:

It is possible that we talk past each other. If you read my last post then that’s exactly what I recommend.

I was in complete agreement and stating that that’s how it’s handle everywhere that I have seen…

Don’t know who fiddles with the lens correction and such… Lightburn stated they used some of that to figure out how fast to move the mirrors.

:smile_cat:

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