DPI Software Limitation?

[typk (Tyler)]

Hi,

I am experimenting to find the best DPI for my laser for photos, I am using a basic gradient jpeg image. I have noticed that I cannot go above 498 DPI when using the Jarvis image mode. I have tried 508, but the output is not correct.

I have manually tested a 508 DPI BMP version of the gradient with passthrough selected and it works as expected. Is this is software limitation or bug?

My maximum DPI seems to be frustratingly between 498 and 508 available.

Please see my images attached.

As you can see below 508 using lightburn mode causes a weird loss in the gradient that isnt present at 500 (498 in software)

You can see the results below 500 are a lot better.

[jkwilborn (Jack Wilborn)]

The lower, faster image appears out of focus to me… your tc start and end times are also off.

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I run 0.025mm interval quite a bit and I don’t have this issue. So I doubt Lightburn has anything to do with it.

This C series lens tube was done at a 0.020mm interval… or 1270 lpi.

[typk (Tyler)]

@jkwilborn

The lower, faster image appears out of focus to me… your tc start and end times are also off.

When I run the image algo it seems to be the case, but with a solid block they seem okay. I think this might be a software issue. See the picture of the solid block at 508 DPI

I followed this guide exactly and configured it to the nearest 10 value so i believe timing is configured correctly? The issue only shows when using the image adjustment feature.

The COMPLETE Guide to Timing and Delay for Galvo Lasers

When I manually use a 508 or more DPI image (The gradient for example) the output is perfect and as expected, however using the adjustment tool you can see that the laser output does not match the preview. See below

Here is the image incase you want to test yourself.

[jkwilborn (Jack Wilborn)]

I have this or one similar… I use this at least weekly if not more often and have never had a problem…

Can/have you tried this with EZCad? It would be interesting…

I can’t run EZCad, but I’ve had no problems adjusting like you seem to be having…

I assume this doesn’t show up on the preview…?

[typk (Tyler)]

@jkwilborn

Can/have you tried this with EZCad? It would be interesting…

EZCad seems to work fine with this, it seems to be only when using the image adjustments in lightburn over 500 DPI

@jkwilborn

I assume this doesn’t show up on the preview…?

I just tested and it does show in the preview which is really odd. Does this confirm its a software issue?

[jkwilborn (Jack Wilborn)]

I doubt it’s the software…

The preview shows what’s going to the laser… you can zoom in an look at what it’s going to do.

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Hang around and maybe @Rick can suggest something…

Worst case, it would be easy to send it to support and ask why you are getting this in the preview…

Send them the lbrn2 file + original and a link to this thread…