Relief Carving

I finally got to try a relief carving from a grey-scale picture. I found the picture on Google (Pintrest) and took into Fusion 360 using the mesh/sculpt tools to create the 3-D image then the manufacture module to create the gcode. I use Octoprint to send the g-code. For the cutting, I used a 1/4" endmill for most of the clearance then a 1/8" ball nose cutter to finish off. I did have to clean it up with some sandpaper but for the most part what you see is what came out of the MPCNC. I am quite pleased with this for a first attempt. If you look closely some of the artifacts from the model around the outside were actually cut. I will work on cleaning that up. I am looking forward to doing more of these, I think the results are worthwhile.

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Nice!

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Fantastic!

Can you share what the greyscale image started out looking like? Iā€™m curious if it was a already prepared height map or just a black and white photo.

Beautiful!

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Here is the original picture

Hereā€™s a search that will find you lots of them:

https://duckduckgo.com/?q=grayscale+image+for+cnc+horse&atb=v121-3o_&iar=images&iax=images&ia=images

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Darn! I was afraid of that. Iā€™ve been on a quest for many many months now looking for the software that makes those greyscale images. Thought maybe all along Fusion was the answer. That image you found has been prepared as a heightmap for 3D CNC relief carving.

I revert back to my most recent conclusions - software to do this doesnā€™t exist. Itā€™s the hard way or no way I think. Iā€™ll keep digging though. I will either master the hard way or find the software way. Somewhere.

I was making 3D comfort bird carvings around Christmas for a local charity with my MPCNC. I scanned the original hand carved model with my iPhone 7S running Qlone, exported the STL file to Meshcam to modify the tail to suit me, imported that STL file to Estlcam running on an Arduino Uno and milled a few. I could have gone directly for Qlone to Estlcam. The camera quality makes a big difference. Itā€™s a two sided milling operation of course. You have to have the raw blocks sized and mounted Exactly the same so when you flip them over everything lines up. By running the Estlcam directly on the Uno I skip the whole export GCode step, I just click on ā€˜mill projectā€™. The 1/8ā€ round nose bit worked pretty well. Two passes per side, one rough and one finish. Cut the tabs on the bandsaw or by hand. I refined the shape a little when sanding up to 320grit then Wipeon Poly finish. In the photo the original is staring at the rest of the flock.

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If you are determined to do relief carvings I think VCarve Pro will do them or more expensive yet, Aspire. The now extinct ArtCam also did relief carvings from grayscale pics.

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Can you describe in more detail what exactly it is youā€™re looking for? I think in another thread you or someone said it was not lithopane, but Iā€™m wondering what it is. Converting an image to grayscale is simple enough and lighter areas will be higher and darker areas will be lower. (Or with lithopane it would be reversed.)

Are you looking to extract 3D information from the 2D image to get a height map of the original 3D scene?

Have you looked at the method this guy uses to make insoles from 2d foot scans? Seems like he is doing something similar to the height maps you are looking for. https://www.thingiverse.com/thing:581443 I think he used openscad in part of workflow. This is the page he shows the software end of this process. http://www.gyrobot.co.uk/blog/my-adventures-with-3d-printed-insoles-part-4-4

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I think I had been mislead at some point in time into believing that ArtCam could take a black and white photo and generate a 3d relief carve. Thatā€™s it in itā€™s simplest.

The reality is (as far as my digging has got me thus far) is that no such magic bullet exists. There are scads of programs that can give you depth based on pixel grayscale values but that results in a lithophane (unless the photo happens to be just perfect in every way that a relief carved lithophane would look good on something opaque - like a slab of wood).

My dream of dreams is to be able to take cherished photographs that people have stashed away and carve them into one of a kind 3d reliefs for them.

Correction - the dream is to use the MPCNC to carve them. I could carve them by hand but the time it would takeā€¦thereā€™s no way people could pay what that time is worth and because of that would decide they couldnā€™t afford the project. If the MPCNC can do the bulk of the heavy lifting it becomes an affordable prospect for people. I donā€™t want to be creating something that only the richest of the rich can afford to indulge in. I want it to be accessible to everyone while still making a comfortable wage for me.

Iā€™ve seen many ā€œtake eight photos with the lights on and two with the lights offā€ solutions and those are amazing. Iā€™m looking specifically for working off a single photograph.

All that said, my post on this quest from a week or so ago shows the closest Iā€™ve yet to come to nailing it. But itā€™s a long process involving the 3d functions in Photoshop and then bouncing back and forth from the 3d output to the source image, manually bringing the tones up every so carefully so they align with the right plane in the carve (STL). Iā€™m pretty confident Iā€™ve got it but wanted to stop on the ā€œtest photoā€ Iā€™d grabbed so that if I did ā€œget itā€ it would be on a photo Iā€™d actually want to carve. I estimate a good 5 or 6 hours to do a portrait. More if itā€™s an image with several faces or a bunch of other stuff happening. So still not in the affordable realm but maybe I can speed up my skills.

Sorry for the hijack Ian.

@geodave, that insole thing is cool - and really close to what needs to happen. The challenge with complex surfaces like faces is that there are so many regions of black that arenā€™t on the plane furthest back (pupils, nostril openings, corners of mouths etc.). But a super fun scanner trick all the same. Worth a play. Itā€™s like ā€œPhotocopier Hijinx 2.0ā€. hahaha

Re: ArtCam. Hereā€™s an excerpt from the Artcam 8 manual

ArtCAM Pro allows you to create a relief from a photographic image containing a side-profile of a personā€™s head and neck saved as a Bitmap (.bmp), TIFF (.tif), GIF (.gif) or JPEG (.jpg) file. This process is almost entirely automated.
To produce a detailed relief, your image should ideally be captured by a digital source using a resolution of at least 1024 x 768 pixels. Colour photographic images can be imported, but they will appear as black and white in ArtCAM Pro.

It was a great program but as usual bought up and disappeared by a competitor. Too bad.

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Ah! Thanks for digging that up. At one point on my quest I thought Iā€™d seen something to that effect but was unable to verify it because it was (I think) only ArtCam Pro that had this feature. Best I could get my hands on was the non pro ArtCam. Yes, I am hunting for a hacked versionā€¦desperate times call for desperate measures.

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[Edit: Just noticed youā€™d indicated ArtCam Pro in your post]

Nice job, I havenā€™t done any two sided carvings yet but I have a set up that is very easy to find the index from. I have a Rambo 1.4 board with the dual end stops. I start there then index out to my ā€œLā€ and clamp against it. If I shut down the MPCNC I can alway get back to the exact same place. To be fair, the repeatability is pretty impressive.

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No worries, itā€™s all good discussion. - I have also been looking into the best way to make the reliefs from a ā€œplainā€ photo. It is my understanding that ArtCam Pro was the best tool for this but AutoDesk bought it and EOLā€™d it. However, if you had a license, AutoDesk provided a perpetual license key. There are some folks on YouTube that are using ArtCam to great effect. Now you can only find ArtCam Free out there and it doesnā€™t do what we want. I have seen a lot of people doing something similar the hard way but it looks very hit or miss. The original photo has to have very even lighting or you will end up with something other than what you want. - I was going to approach the authors of the photos that I found however, they all seem to be Chinese with no real contact information. There are ample pictures out there but they are not really custom if they come from stock photos.

I will continue to investigate/experiment and come back here if I find something that is half way ā€œeasyā€ to achieve what we want. I hope you will do the same.

I will absolutely share. In fact when I figure out the ins and outs of the hard way Iā€™ll definitely write that up as well!

Thanks for clarifying. This sounds like a very hard problem. Mathematically speaking, the depth information is unrecoverable from the 2-D image, but even though it is ā€œimpossibleā€ to recover the information, the brain is nonetheless very good at inferring depth when looking at a recognizable subject. To me this sounds like one of those areas where traditional algorithms will never really work, but one of those new-fangled neural networks might be able to get some traction.

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Barry made me test this at MRRF, I was honestly impressed myself. We were running a 7"x9" highly detailed plot with a 0.3mm gel pen. Let the first one run, home the machine, run number two right on top. You could not tell at all, maybe slightly darker lines but that was to be expected. Kinda cool, thought I would share.

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I thought I would share a picture of the relief carving after my wife painted it

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I did another relief carving of our horse. This was from a standard color photo. Without the painting (done by my wife) it was hard to recognize it as a horse LOL. I have been working on better ways to get a decent relief carving from a photo. I have realized there is no automatic way to get a good height map from a photo. You have to look at the attributes and decide which parts you want to be elevated and ensure they are white/lighter in color. Once I have a good process down, I will come back and post it here.