# \#focus **URL:** https://forum.lightburnsoftware.com/tag/focus/67.md [Latest](https://forum.lightburnsoftware.com/latest.md) · [Categories](https://forum.lightburnsoftware.com/categories.md) · [Tags](https://forum.lightburnsoftware.com/tags.md) --- ## [Designing a universal time of flight z compensator](https://forum.lightburnsoftware.com/t/designing-a-universal-time-of-flight-z-compensator/97406)
**Author:** [@julienrl](https://forum.lightburnsoftware.com/u/julienrl)\ **Replies:** 45\ **Last updated:** [June 11, 2026, 1:26pm UTC](https://forum.lightburnsoftware.com/t/designing-a-universal-time-of-flight-z-compensator/97406 "2026-06-11T13:26:48Z")
Hello, I work a lot with fairly large 3mm sheets (50cm x 30cm +) and warping is quite an issue for me, so I’ve decided to design a live servo z height compensator with 0.1mm resolution. The idea is to make it stand-alone… --- ## [Where is the Focus 'button'](https://forum.lightburnsoftware.com/t/where-is-the-focus-button/187596)
**Author:** [@HenryM](https://forum.lightburnsoftware.com/u/HenryM)\ **Replies:** 3\ **Last updated:** [February 15, 2026, 12:36am UTC](https://forum.lightburnsoftware.com/t/where-is-the-focus-button/187596 "2026-02-15T00:36:03Z")
I am using Lightburn with an xTool S1. I have not used it for a few months and I have forgotten where the Focus button is. I looked for it on the Laser window but could not see it. I thought that when I used this, the… --- ## [Adding layer focus parameter](https://forum.lightburnsoftware.com/t/adding-layer-focus-parameter/187430)
**Author:** [@roncpa](https://forum.lightburnsoftware.com/u/roncpa)\ **Replies:** 3\ **Last updated:** [February 7, 2026, 12:25pm UTC](https://forum.lightburnsoftware.com/t/adding-layer-focus-parameter/187430 "2026-02-07T12:25:14Z")
Is it possible to add a focus parameter for each layer? It coud be a percent for out of focus burning, where 0 is in focus and + or - could be for slightly putting the beam out ot focus. This can improve offset fill or e… --- ## [Trouble setting focal length](https://forum.lightburnsoftware.com/t/trouble-setting-focal-length/177564)
**Author:** [@kmh](https://forum.lightburnsoftware.com/u/kmh)\ **Replies:** 3\ **Last updated:** [August 13, 2025, 10:59pm UTC](https://forum.lightburnsoftware.com/t/trouble-setting-focal-length/177564 "2025-08-13T22:59:39Z")
I am having trouble setting the focal length. I updated to 2.0.02 I typically use a caliper to measure the focal distance, then use the move tool in the move tab, to adjust the height until I hit 47.8. The necessary f… --- ## [Focus Test Z-Axis Moves but fires on the same at 0](https://forum.lightburnsoftware.com/t/focus-test-z-axis-moves-but-fires-on-the-same-at-0/173436)
**Author:** [@texasparamedic](https://forum.lightburnsoftware.com/u/texasparamedic)\ **Replies:** 0\ **Last updated:** [June 12, 2025, 6:49pm UTC](https://forum.lightburnsoftware.com/t/focus-test-z-axis-moves-but-fires-on-the-same-at-0/173436 "2025-06-12T18:49:39Z")
I am stumped and can not seem to find any info. I have a OneLaser Hydra 9, Ruida Controller RDC6442G-LY-1G-GT5-DL. Using Both the Production Lightburn 1.7.08 and the PreRelease 2.0.00 RC-7. When I try to use the focus te… --- ## [Laser focusing above expected focal height](https://forum.lightburnsoftware.com/t/laser-focusing-above-expected-focal-height/132423)
**Author:** [@RE\_KOTE\_LLC](https://forum.lightburnsoftware.com/u/RE_KOTE_LLC)\ **Replies:** 5\ **Last updated:** [July 9, 2024, 2:58pm UTC](https://forum.lightburnsoftware.com/t/laser-focusing-above-expected-focal-height/132423 "2024-07-09T14:58:38Z")
Hello all, I have a cloud ray 50w fiber with a f=420mm lens for a 300mmx300mm working area. When I first purchased the laser I adjust the focus by burning steel and adjusting the height until optimum burning based on a … --- ## [Engraving from a greater distance than the focal depth](https://forum.lightburnsoftware.com/t/engraving-from-a-greater-distance-than-the-focal-depth/131421)
**Author:** [@woodlaser](https://forum.lightburnsoftware.com/u/woodlaser)\ **Replies:** 15\ **Last updated:** [March 6, 2024, 10:05pm UTC](https://forum.lightburnsoftware.com/t/engraving-from-a-greater-distance-than-the-focal-depth/131421 "2024-03-06T22:05:08Z")
Hello, Does anyone have a way to engrave wood from 0.5 inches above the normal focal height? I have made some wooden heart jewelry trays with a router and template, the hearts are about 3.4 inches wide. I am trying to … --- ## [How to set negative focus test numbers?](https://forum.lightburnsoftware.com/t/how-to-set-negative-focus-test-numbers/127900)
**Author:** [@ziplock9000](https://forum.lightburnsoftware.com/u/ziplock9000)\ **Replies:** 8\ **Last updated:** [February 5, 2024, 2:05pm UTC](https://forum.lightburnsoftware.com/t/how-to-set-negative-focus-test-numbers/127900 "2024-02-05T14:05:43Z")
In this thread, the Lead Dev @LightBurn mentioned that the focus test can be set to a -ve to +ve number, which is logical as you want to test both sides of the 0 focus. However the UI only allows +ve numbers… How can th… --- ## [Seeking Advice on 101.6mm (4") Lens Focusing Issue for 90W CO2 Laser Cutter](https://forum.lightburnsoftware.com/t/seeking-advice-on-101-6mm-4-lens-focusing-issue-for-90w-co2-laser-cutter/124321)
**Author:** [@MichMich](https://forum.lightburnsoftware.com/u/MichMich)\ **Replies:** 7\ **Last updated:** [January 11, 2024, 6:31pm UTC](https://forum.lightburnsoftware.com/t/seeking-advice-on-101-6mm-4-lens-focusing-issue-for-90w-co2-laser-cutter/124321 "2024-01-11T18:31:08Z")
Hello everyone, About two years ago, I successfully designed and built a 90W CO2 laser cutter, which has been running exceptionally well. I’ve primarily used a ZnSe Meniscus Focus Lens (20mm / 63.5mm or 2.5") for crisp … --- ## [Focus test placement](https://forum.lightburnsoftware.com/t/focus-test-placement/85173)
**Author:** [@davorin](https://forum.lightburnsoftware.com/u/davorin)\ **Replies:** 1\ **Last updated:** [December 16, 2022, 10:44pm UTC](https://forum.lightburnsoftware.com/t/focus-test-placement/85173 "2022-12-16T22:44:30Z")
Good morning Just installed a new LED laser on my Anycubic X machine and want to do a focus test… Is there a way I can set the size and placement of the focus test? I’m using a large piece of wood where I want to run … --- ## [Focus test Z travel to 100mm](https://forum.lightburnsoftware.com/t/focus-test-z-travel-to-100mm/82883)
**Author:** [@davorin](https://forum.lightburnsoftware.com/u/davorin)\ **Replies:** 1\ **Last updated:** [November 26, 2022, 2:36pm UTC](https://forum.lightburnsoftware.com/t/focus-test-z-travel-to-100mm/82883 "2022-11-26T14:36:18Z")
Good afternoon (o; Completed my retrofit of an Anycubic Mega X printer to a small LED laser engraver: But as the Z-height is over 200mm for this machine I see that the focus test parameters are limited to 100mm maxi… --- ## [Focus test and negative Z-coordinates](https://forum.lightburnsoftware.com/t/focus-test-and-negative-z-coordinates/82507)
**Author:** [@davorin](https://forum.lightburnsoftware.com/u/davorin)\ **Replies:** 3\ **Last updated:** [November 23, 2022, 9:10am UTC](https://forum.lightburnsoftware.com/t/focus-test-and-negative-z-coordinates/82507 "2022-11-23T09:10:58Z")
Good morning As I have a FluidNC machine with a small laser attached I want to try the “focus test” feature. So I enabled the Z-axis in the machine settings… Do I need to set anything else specifically when my machine… --- ## [Focus test preview issue](https://forum.lightburnsoftware.com/t/focus-test-preview-issue/77441)
**Author:** [@amessiah](https://forum.lightburnsoftware.com/u/amessiah)\ **Replies:** 1\ **Last updated:** [September 28, 2022, 11:23pm UTC](https://forum.lightburnsoftware.com/t/focus-test-preview-issue/77441 "2022-09-28T23:23:17Z")
I noticed, that in LaserTools - Focus Test, after you pressing Frame button and laser head moving over area, IT NOT counting offsets from options, but when you start engrave - offsets applied and that Frame button showed… --- ## [Preventing head crash with Focus Test](https://forum.lightburnsoftware.com/t/preventing-head-crash-with-focus-test/76663)
**Author:** [@proski](https://forum.lightburnsoftware.com/u/proski)\ **Replies:** 1\ **Last updated:** [September 19, 2022, 11:40pm UTC](https://forum.lightburnsoftware.com/t/preventing-head-crash-with-focus-test/76663 "2022-09-19T23:40:26Z")
I crashed my brand new 4" head today when doing Focus Test. I set up reasonable limits for the low and high Z positions. However, LightBurn commanded the laser to raise the table above that limit after making the first l… --- ## [How to translate Focus test to z axis settings](https://forum.lightburnsoftware.com/t/how-to-translate-focus-test-to-z-axis-settings/76039)
**Author:** [@Marjan](https://forum.lightburnsoftware.com/u/Marjan)\ **Replies:** 1\ **Last updated:** [September 10, 2022, 12:48pm UTC](https://forum.lightburnsoftware.com/t/how-to-translate-focus-test-to-z-axis-settings/76039 "2022-09-10T12:48:51Z")
Hi all, I just got a two trees TS2 and I’m having a fight with the auto focus. If I use the settings provided it is not focuses correctly. I’m just trying to cut some 3mm plywood and keep getting a flame alarm, and re… --- ## [Emblaser 2 laser calibration](https://forum.lightburnsoftware.com/t/emblaser-2-laser-calibration/64405)
**Author:** [@beckbuffalo](https://forum.lightburnsoftware.com/u/beckbuffalo)\ **Replies:** 5\ **Last updated:** [April 14, 2022, 1:11am UTC](https://forum.lightburnsoftware.com/t/emblaser-2-laser-calibration/64405 "2022-04-14T01:11:47Z")
Cannot get my laser to create any lines on the calibration card using the LightBurn laser calibration tool. The beam seems to be very large and will not make a mark on the paper. Z-axis movement is fine. Any ideas? --- ## [Focus test - unintended movement and crash](https://forum.lightburnsoftware.com/t/focus-test-unintended-movement-and-crash/63217)
**Author:** [@Pethical](https://forum.lightburnsoftware.com/u/Pethical)\ **Replies:** 4\ **Last updated:** [March 26, 2022, 7:35am UTC](https://forum.lightburnsoftware.com/t/focus-test-unintended-movement-and-crash/63217 "2022-03-26T07:35:33Z")
Hi, I’m using my machine with absolute coordinates. I used it before with the actual position setting. I changed today something on my laser head and wanted to do a new focus test. When I started it moved my laser head … --- ## [Z-Axis problems with RDC6332M with LFS-PM-T43 (capacitive Z-sensor)](https://forum.lightburnsoftware.com/t/z-axis-problems-with-rdc6332m-with-lfs-pm-t43-capacitive-z-sensor/54729)
**Author:** [@Wubbe](https://forum.lightburnsoftware.com/u/Wubbe)\ **Replies:** 1\ **Last updated:** [December 18, 2021, 5:02pm UTC](https://forum.lightburnsoftware.com/t/z-axis-problems-with-rdc6332m-with-lfs-pm-t43-capacitive-z-sensor/54729 "2021-12-18T17:02:27Z")
Hi there! I’m new to the laser world. I’m having problems with my Z control. When cutting metal I can adjust the height for piercing and cutting, so far it’s ok! But when cutting and engraving nonmetals I need to unche… --- ## [Z/U Axis Bed Won't Go Up, Only Down After Autofocus - How to Disable Z/U End Stop?](https://forum.lightburnsoftware.com/t/z-u-axis-bed-wont-go-up-only-down-after-autofocus-how-to-disable-z-u-end-stop/44385)
**Author:** [@AlteriusOmega](https://forum.lightburnsoftware.com/u/AlteriusOmega)\ **Replies:** 0\ **Last updated:** [July 19, 2021, 4:21am UTC](https://forum.lightburnsoftware.com/t/z-u-axis-bed-wont-go-up-only-down-after-autofocus-how-to-disable-z-u-end-stop/44385 "2021-07-19T04:21:19Z")
HI all, I have a red and black 60W Ruida laser, and after I use the autofocus feature, I can’t make the bed go up at all, only down. I’m guessing this is some safety feature so you can’t accidentally crash the bed into … --- ## [Focus the laser](https://forum.lightburnsoftware.com/t/focus-the-laser/25462)
**Author:** [@woodshop51](https://forum.lightburnsoftware.com/u/woodshop51)\ **Replies:** 0\ **Last updated:** [November 8, 2020, 10:57am UTC](https://forum.lightburnsoftware.com/t/focus-the-laser/25462 "2020-11-08T10:57:56Z")
Hi, new the laser engraving business and i cant work out how to just fire the laser so i can focus the beam depending on the thickness of the wood. Any help would be greatly appreciated. Thanks --- ## [Feature request re: z-focus](https://forum.lightburnsoftware.com/t/feature-request-re-z-focus/23933)
**Author:** [@Bigjohn](https://forum.lightburnsoftware.com/u/Bigjohn)\ **Replies:** 2\ **Last updated:** [October 16, 2020, 4:58pm UTC](https://forum.lightburnsoftware.com/t/feature-request-re-z-focus/23933 "2020-10-16T16:58:53Z")
Can we get a prompt that says “Confirm head placement?” or some such… Wife does not use the laser often, and changed material - so she went to focus (glowforge user) and… damn. God bless E-STOP! So when you hit “z-foc… --- ## [How to Focus Diode Laser](https://forum.lightburnsoftware.com/t/how-to-focus-diode-laser/21262)
**Author:** [@carsfischer](https://forum.lightburnsoftware.com/u/carsfischer)\ **Replies:** 2\ **Last updated:** [August 30, 2020, 7:40pm UTC](https://forum.lightburnsoftware.com/t/how-to-focus-diode-laser/21262 "2020-08-30T19:40:56Z")
I am brand new to laser engraving so apologies for my basic question. I have a 15000 mw Blue CNC Laser Engraving Machine. It is a diode laser. How do I focus the laser? Thanks! --- ## [How do I turn on my diode at low power to focus it or frame a job?](https://forum.lightburnsoftware.com/t/how-do-i-turn-on-my-diode-at-low-power-to-focus-it-or-frame-a-job/10520)
**Author:** [@LightBurn](https://forum.lightburnsoftware.com/u/LightBurn)\ **Replies:** 0\ **Last updated:** [January 5, 2020, 6:27pm UTC](https://forum.lightburnsoftware.com/t/how-do-i-turn-on-my-diode-at-low-power-to-focus-it-or-frame-a-job/10520 "2020-01-05T18:27:06Z")
Diode lasers often don’t have a red-dot pointer like CO2 lasers do, so it is often useful to enable them at low power for focusing or framing. (Please do NOT do this if you have a CO2 laser, as the beam is invisible and…