AUTOMATED NATIVE LENS CORRECTIONS IN LIGHTBURN (No Ezcad!) 

I ran into this helping someone yesterday too. We'll be doing some troubleshooting and documenting things to try and help address that. Haven't found a pattern to it yet, but you can get around that by going to lightburn settings and disabling the line item for ignoring items outside the work area. I would enable it again when done, but it should get you through the process. Additionally, there seems to also be a scale problem sometimes. The rest of the calculations seem to be working well, but sometimes the scale on either X, Y, or both, tends to make the work area too big and scale output accordingly too large. This can be mathed out manually to accurately scale down by making a square of a known size and then adjusting by the % it is over, scaling it down by that value on the given axis scale (over simplified version of the explanation but best we can do in the comments lol). Hope that helps, and we'll try and submit feedback to the awesome team at LB to try and help improve things as we test and try and find details that may help them. I'm hopeful this should be a quick fix in a future update, and this is still useful as is anyway given that we only have to adjust scale with some quick math and the rest seems to be perfect :) Stay tuned!

@@LaserEverything I am having the same issue with my 70mm lens as well, when I am looking at it the Box extends passed the corners. Not sure if this data is helpful or not.

i have the same problem but I try the 50x50 lens f63.

I am facing the same issue after lightburn new future, it marks a square 2mm off X side compared to Y side for example, it marks 50 x 50 as 52x48

It's easy to fix - lets say your marked box should be 50 x 50 but it marks as 48.5 wide x 52 tall.Go to your Device settings. Look at Galvo 1 and Galvo 2 'scale' percentage values. To adjust: The formula is: current scale percentage value times desired length divided by actual mark length. eg if actual mark is smaller than desired (should be 50mm wide but you got 48.5mm wide mark and your scale percentage currently is 91.2329%) The formula is: 91.2329 x 50 / 48.5 = 94.0545% - set this as your new scale percentage for x axis. If actual mark is bigger than desired (should be 50mm tall but you got 52mm tall mark and your scale percentage currently is 82.3219%) The formula is: 82.3219 x 50 / 52 = 79.1557% - set this as your new scale percentage. Once you adjust the scale percentage for both axes, try marking the 50x50 box again, and you should see it come out the correct size.@@akbarazadazad1453

Shared this above, but just so you guys see too. I ran into this helping someone yesterday too. We'll be doing some troubleshooting and documenting things to try and help address that. Haven't found a pattern to it yet, but you can get around that by going to lightburn settings and disabling the line item for ignoring items outside the work area. I would enable it again when done, but it should get you through the process. Additionally, there seems to also be a scale problem sometimes. The rest of the calculations seem to be working well, but sometimes the scale on either X, Y, or both, tends to make the work area too big and scale output accordingly too large. This can be mathed out manually to accurately scale down by making a square of a known size and then adjusting by the % it is over, scaling it down by that value on the given axis scale (over simplified version of the explanation but best we can do in the comments lol). Hope that helps, and we'll try and submit feedback to the awesome team at LB to try and help improve things as we test and try and find details that may help them. I'm hopeful this should be a quick fix in a future update, and this is still useful as is anyway given that we only have to adjust scale with some quick math and the rest seems to be perfect :) Stay tuned! Edit: Just seeing@imakethings17 's shared the formula they used to correct scale. good info, you explained it far better than I was able to in text lol

@@imakethings17 This worked perfectlly, thanks!

@@ssullivan I'm glad it helped. I'm sure others will have the same issue so as long as they follow those final checks and adjustments it should give them perfect settings.

Saaaaaaaaaaaaaaame!

You are literally the best, thanks man! We appreciate every bit of what you guys do

Agreed!

Glad it was helpful!

Hope you enjoy it!

Our pleasure!

I manually measure diagonals on ezcad, but you are right!

A bloke called Pythagoras disagrees with your assertion. I'm not saying this is doing it, but from the measurements taken you can plot the position of every intersting line in relation to the centre point. If the 12 lines that make the grid are all equal you must have 4 squares inside a square.

Pythagoras, triangle = diagonals... :) Skew is about making a parallelogram, al lines are equal length and it does NOT have to be square.

@@timg6252 Nope, I'm afraid that's not the case. The simplest way to demonstrate this is to look at the following: imajeenyus.com/temp/no_skew_demo.jpg Pretend that those are two different marked patterns. The pattern on the left is ideal, while the pattern on the right has severe skew. In both cases, the distances between the points (the lengths of the lines) are all 50mm. In both cases, you would measure and enter exactly the same values into either corfile2 or the new Lightburn feature. Yet one situation clearly has skew, the other doesn't. Now, the instructions do say to measure the distance "from each indicated point to the HORIZONTAL center line". In other words, the red line I've shown on the right-hand drawing. That's fine in theory, but in practice the difference between that measurement and the point-to-point distance will be so small as to be unmeasurable by eye with a digital caliper. For example, suppose you have a 2° skew angle, which is significant. If the point-to-point distance is 50mm exactly, then the perpendicular distance will be 50*cos(2°) = 49.97mm. No way is it possible to measure that accurately. Besides, I can easily demonstrate another marked pattern which has skew, yet where all the perpendicular distances are equal to 50mm. I spent several months tearing my hair out over how exactle corfile2 performs its calculations, and finally determined that there is indeed no way for skew correction to be performed, doing the measurements this way. Brief background: the COR file that is produced contains a 65x65 array of "displacement" values for both galvos, which is sent by EzCad to the BJJCZ controller board. The controller receives an uncorrected galvo position from EzCad, looks up the array to find how much it should displace that position, and then sends _that_ position to the actual galvos. Take a look at this graphic: imajeenyus.com/temp/cor_file_random_values.jpg That is a representation of the displacements for each of the 65x65 points in the array - the short black lines show the direction and magnitude of the displacement. The important thing to note here is that the on-axis displacements are always ALONG the axis (the short black lines along the X axis are all horizontal, and those along the Y axis are all vertical). Skew correction can never be performed this way, and I experimented with numerous different values. This isn't to say that the COR file approach itself is bad - it's only corfile2 that's poor. The COR file itself can indeed handle any arbitrary corrections you like - I have written my own script which will perform a 5x5 grid correction based on marking a grid of holes and then measuring the actual coordinates of each. However it's still very much a work in progress. The only reliable way to determine skew would be to measure _diagonal_ distances, but I'm not entirely sure how the calculations would go....

@@timg6252 (I previously wrote a reply to this, but it seems to have not posted) Nope, not the case. I can show you two different mark patterns, one with severe skew, yet both with all distances equal to 50mm: imajeenyus.com/temp/no_skew_demo.jpg

Hey Ben, hit up the link in the description for our free discord or facebook group and we can check it out!

There are other values that handle that for us, with delay and timing values. The LB team had a set of parameter limits on it and has since been updated :)

Ok? Do you have a laser, are you using Lightburn?

We'll absolutely be covering that too, in a dedicated video :)

100% yea. Always in focus

Ideally, you'd set up a "device" in lightburn for each lens size + machine. So if I have 3 lenses for my 50w fiber, I'd say 50w fiber 110 lens, 50w fiber 200 lens, 50w fiber 300 lens, as an example. This way each lens for the machine will have its own profile and be tuned. We do the same for parameter libraries as well, since they change based on lens size and such. Each correction is specific to the lens, like a fingerprint. So for best results, you'd do this process for any new lens setup. We have an updated video coming that includes the whole process, start to finish on a new lens config and tune (updated from this even, its in editing).

We have a great video for that. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-JwWV6Hki5Dk.html

🐉

Be sure you have a galvo device selected, this feature will not appear when using a gantry device.

Join one of our many support communities I'm sure someone can help. Definitely will need to see some pics. Links to everything in the description, lots of free options.

That is correct. Note it's only on the current public beta and not available on the normal channel as of yet. When this update releases on the public channel we'll make an announcement about that as well. Otherwise - you'll just want to be sure to grab the current BETA version of the software to access this feature.

Awesome I may finally be able to use lightburn

I don't think I'm up to date on that information but when we have news we will definitely share it.

I ran into this helping someone yesterday too. We'll be doing some troubleshooting and documenting things to try and help address that. Haven't found a pattern to it yet, but you can get around that by going to lightburn settings and disabling the line item for ignoring items outside the work area. I would enable it again when done, but it should get you through the process. Additionally, there seems to also be a scale problem sometimes. The rest of the calculations seem to be working well, but sometimes the scale on either X, Y, or both, tends to make the work area too big and scale output accordingly too large. This can be mathed out manually to accurately scale down by making a square of a known size and then adjusting by the % it is over, scaling it down by that value on the given axis scale (over simplified version of the explanation but best we can do in the comments lol). Hope that helps, and we'll try and submit feedback to the awesome team at LB to try and help improve things as we test and try and find details that may help them. I'm hopeful this should be a quick fix in a future update, and this is still useful as is anyway given that we only have to adjust scale with some quick math and the rest seems to be perfect :) Stay tuned!