Testing the Four Scoring Options

As both the old settings look better than the new ones how is this a step forward?

I would expect them all to give the same darkness of engrave by using more power on fast / draft to compensate for the speed. So they only difference should be the time taken and the evenness, not general lightness / darkness.

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I don’t agree. I think HQ looks best for most situations; Slow is just a little too dark for me (too much burn in the center) and Fast a little too light. But of course we can always adjust to suit the demands of the project. I just think HQ will be the best default.

Crossing in the centre is a special case. Whenever you have lines crossing it will be over engraved and that centrepoint is an extreme case. And acute corners overlap the beam, so again some over engraving is to be expected. Ignoring that, I think that “slow” is the most even between line centre and corners. Seems off that that is better than “quality”. Maybe they aren’t swapped, perhaps the first one simply has a typo and is just wrong.

Regardless though if the choice is between fast / slow or high quality / draft they should target the same engrave depth / darkness by keeping the power density constant while trading speed and power.

From the wording on the announcement I would have thought that the overburning in the corners would have been addressed better in the HQ. As it is, the HQ also is ‘lighter in the middle and creates dark spots on corners’. HQ simply looks like a darker ‘Fast’ to me in this image. This is just one picture of one sample, and might not be the best test of what was achieved, so might just be an outlier.

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I think the overburning on corners is due to the acceleration of the head. Since acceleration isn’t instantaneous the places where the head change directions or start/stop will always get more heat than places where the head is at speed. This isn’t apparent in Slow because of the low max speed and everything looks dark anyway so it’s hard to tell a difference, but I think it’s pronounced in HQ because of the high speed.

You can actually see that in the HQ engrave on this sample there are places where it’s the middle of a line but there’s definitely some extra burn:

Capture

That’s because this file was originally meant for print and not laser. The path actually breaks there so there’s de/acceleartion going on there, leading to a slightly darker spot. So yes, this one sample file probably isn’t the best test.

I think the differences wouldn’t be as pronounced if the use case was for something like the Gift of Good Measure where the scoring are continuous curved paths with minimal sharp turns (@palmercr: I think the acute corner burns are both from the double burning and the abrupt change in velocity) then it would look great. So yeah what @cynd11 said.

I chose this file because my general use for score is to etch out small, sharp, angular patterns. (See Quilt Block Coaster) The ways I can think of to fix that in the software would be to either have the laser shut off at the corner while the head maintains speed for a little longer (which would probably be hard math-wise and will reduce print area) or to reduce power as a function of the speed decrease (I am not a real engineer but I know enough to know that’s probably gonna be a nightmare to do). So honestly I don’t expect any setting to look perfect for my use case but HQ looks like it’ll be good enough if I make my file better. And by looking at these presets and how they come out I now have an idea on what I’d need to change manually if I decide HQ isn’t good enough.

It’d be cool to see what test patterns the GF engineers used and how those look in HQ vs the old settings, or maybe someone using scoring in a more “normal” circumstance.

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Understood about the reason for the extra darkness at the ends. This has been discussed before:

From the wording of the announcement I thought one of the reasons for the new settings was to address this. I was probably reading too much into it.

Ah, didn’t see those before. Thanks!

3D printer slicer software solved this (over-extrusion while slowing in corners) ages ago. It took some sophisticated logic to make it work right, so I’d hope that GF is looking at the Marlin/Sailfish acceleration code.

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Turns out I made a mistake on what the bug was. It wasn’t a mislabel, it’s a wrong number in the HQ settings. So what I’ve been thinking of as HQ (and what we have been talking about) is actually for real Draft. I’ve edited the top of this thread with more detail on this and is running an new test now. Will post results in a bit.

Okay now that the settings are correct (thanks support!) I reran the test with the same file.

From left to right: High Quality, Draft, Fast, Slow.

Everything above this post, we thought Draft was HQ. The real HQ is here. It looks pretty much like the old Slow, but darker and doesn’t cut as deep (lost the side view piece before I took a picture :frowning:). I like how it looks and I’m going to see how it does on a bigger piece when I have time. So instead of what I thought before—we get a thing that’s in between the old settings and a useless thing—we actually get improved versions of both old settings.

I am a fan of this change now. Yay! <3

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The fixed HQ looks great. Less corner overburn.

The fixed HG looks a bit better than slow and draft is better than fast so there is progress but draft is also a lot lighter than HQ. I would expect them to target the same darkness using different power / speed trade-offs.

It seems that they roll out new settings without testing them. Not good when thousands of people are using them and potentially wasting materiel.

I’ve seen you say this before and I don’t understand. Why would we want two different settings to achieve the exact same appearance? From a user’s perspective, I want a different look for each setting.

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If they were called light and dark I would expect them to look different shades. If they are HQ and draft I would expect them only to differ in quality, i.e. evenness and the time taken. Draft should be fast andt with a bigger variation but not overall lighter.

Otherwise there should be four combinations on two axes i.e. draft light, draft dark, HQ light, HQ dark.

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Hmmmmm. That may make sense from an engineer’s perspective but the average user would be unlikely see it this way, and will prefer it the way Glowforge has done it. At least, that is my preference. It’s inline with what one is used to seeing from a 2D laser printer dialogue.

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Okay, I’m happy with the progress now! From what the image shows, the lines are very nicely even end to end.

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With a 2D laser draft mode is to save ink, so it is lighter by definition. My understanding of this is to trade quality for speed but faster doesn’t need to be lighter as you can compensate with more power.

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Exactly so the ‘average Joe’ reads draft and assumes lighter. Its just a reflection of the language and current expectation of seeing the word draft.

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With a laser engraver you can make it lighter and keep the same quality by just reducing the power. Or you can go faster with increased power to get the same darkness with lower quality. Seems odd to conflate the two. Makes no sense at all to me but I seem to be in a minority of one.

I get where you’re coming from. Its that we’re talking about a preset on the UI thats called Draft so I believe the term should follow the expected connotation. Just as you said above, I would expect it to be lighter because thats the common experience with laser and ink jet printers.

Afterall, this is a Laser “Printer” according to the website. :smirk:

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