Over Christmas I decided to tackle a new project that was very special to me. This particular 3d piece was a Christmas present for my dad who is an avid guitar enthusiast and amateur performer. In this first of what I hope will be many post mortems I walk through some of the challenges I faced throughout the project, some things I picked up and learned along the way, and what I might do differently looking back.
What Is a Post Mortem?
The phrase post mortem is a latin phrase meaning ‘after death’. In relation to projects post mortems are a focused look back on a finished project with the intent of gleaning as much wisdom from the experience as possible. Usually this involves careful contemplation surrounding decisions made throughout the project. Some parts of a project tend to go smoothly and other parts are more of a challenge. Spending some extra time with the projects after they’re finished help provide a means for taking away extra insight from the creation process. So these posts are meant to point out things I learned, thought might be interesting to know, or were things that occurred that might be avoided during the next project.
The Idea: A Custom Electric Guitar
So my dad has been talking as far back as I can remember about wanting to have a drawing or an art piece from me to hang in his office. And this was one of those projects I always planned on getting around to, but I never quite found the right time or piece to work on for my dad. So since I’ve been trying to work on fleshing out and updating my portfolio lately I decided to model him a custom guitar and put together a big oversized poster for him as a Christmas present.
As with most projects the idea started as something huge and impossible and I had to work on narrowing down and getting creative with the design so that I could finish it in time for Christmas. I ended up working about two weeks total off and on to get this finished. I’d estimate that around 10 hours were spent getting the model finalized and then another 10 hours were spent working on the custom shaders, studio lighting, and compositing in Photoshop.
What I ended up with was a Gibson 335 that had customized wood finishes, completely original pearl inlays for the fret markers, and a really unique burnt cherry color. But this project was full of many challenges and ups and downs. So let’s talk about what I learned . . .
Starting Off On the Right Foot
Tackling Any Project Starts with Solid Reference
I knew from past projects that the one thing that would boost my confidence starting such a large and complex model would be feeling like I knew what I was doing. This ultimately starts with getting your hands on some good reference material. So, like all projects, I spent several hours scouring the corners of the internet looking for as many high resolution photos of the guitar as I could.
One of the really important things to try to find for a model like this that already exists in the real world is blueprints. And I couldn’t get my hands on the exact blueprints for this guitar, but I got close enough with some plans I found on Google. After I found those I did my best to find as many angles of the guitar and closeups of the details as I could so that I had adequate coverage and I wouldn’t have to stop what I was doing to go digging every time I needed to model another part. These are some photos I managed to take of my dad’s personal guitar collection.
The best advice I can give you when looking for reference is try to imagine that you’re going to be giving these photos to a robot and telling the robot to build something using just the photos. Would that robot have enough information to look at in order to create an accurate replica? If you had to create a 3d scanned model do you have anywhere near the angle coverage you would need for a process like that? I don’t think you can have too much reference. In my opinion more is always better. And for a project like this no two pictures of the same thing were actually the same. And I knew the more photos I found the more accurate the model I created would appear. It’s really about educating yourself on how something really looks versus how your mind thinks something looks. When I think of trying to sketch something this is a big factor. Do I know how to draw something, or do I think I know how to draw something. Winging it on projects like this land you in a pile of hurt because you waste a lot of time working off the wrong information.
After I felt like I had enough angles of the guitar and pieces of the parts I started to focus on making sure I had photos that were giving me ideas for my final render. I wanted to create a final shot that was fairly minimalistic and had studio lighting showing off the features of my model. So I went straight to the manufacturer’s website to find the highest quality photos for lighting reference that I could.
Don’t Bother with Details You’ll Never See
At several times during the project I was confronted with the decision about whether or not to include small details on sections of the guitar. An electric guitar is made up of several hardware components and despite what it might look like at a first glance many of those components are fairly complex in composition. The bottom line here is that if you aren’t going to see something in the final render then you shouldn’t waste time working on it.
I think one of the things I could have done a little better with this project would be to focus on locking in the macro details of the project at the block out stage. Doing this gives you an accurate roadmap to follow regarding how to split up your time during the project. Most of the composition can be predicted with a rough block out of the final render.
Blocking out typically includes basic low-res models, some indication of all the materials needed for the scene, and as close to a locked in camera placement and lighting setup as possible. The closer you can get things locked in at this early stage the easier it will be to optimize your time focusing on the important details of your scene and avoiding frustration during the later stages of the project. Something you might spend hours working on could get covered up by another object in the foreground in the final render so it pays dividends to think about that early on in the process.
Meshes, Shaders, and Lights . . . Oh My!
So for a model that’s as involved as this guitar it’s easy to get tunnel vision and just think about the model by itself. And as a 3d modeler I’m really guilty of this because modeling is my favorite part of the process and it always comes at the beginning when my enthusiasm for the project is still at its height. So I can spend hours, days, and even weeks working on something just because I like what I’m doing. Or sometimes I just toil away trying to get something perfect without a care in the world. And that’s not always the best use of time. We’re not just working on a model here. We’ve got several other steps to finish before hitting that render button. So budgeting your time and more importantly your energy is important over the duration of a project. Remember this isn’t a sprint, it’s a marathon.
So in this case building the model is only about ⅓ of the process for completing the project. And for this project I also had to spend quite a bit of time perfecting the lighting and the shaders. Oh did I mention that all the shaders for the guitar here are procedurally built from scratch? Yeah, so that was a little side challenge I had going. I wanted to take a crack at doing fully procedural shaders that were built from the ground up. And this by itself wasn’t a big deal until I got to the wood shader for the guitar. That’s where I had to stretch myself a little bit.
The Wood Shader
One of the most important material elements for a guitar is the look and feel of the wood used for the neck and body. Typically these are made from two or more different types of wood such as ebony, mahogany, maple, or exotic rosewood. And the process for polishing the wood and adding the unique finishes can take weeks. So nailing the wood shader was really important to me for this project and as a special challenge I didn’t just want to resort to using photo textures to help me speed things up. I wanted a really unique feel to the wood that was flexible and allowed me to shape it until it fit in with the look of the guitar.
So building procedural wood in Blender with a particular look is one of those things that is exactly as hard as it sounds. I spent many hours doing research and experimenting with techniques until I found a good combination of results for my wood. Going back to my folder full of reference was key because I had a lot of closeup shots of the wood that I was trying to recreate and it helped me build up the effects in layers until I was completely satisfied. It turns out two things were really key to making this work. The first was the manipulation of the vector data for the wood textures in the node chain. I used the ‘Separate RGB’ and ‘Combine RGB’ nodes to break apart the red, green, and blue components to manipulate them before recombining them back together and passing them on through the shader network. The second technique was the method used to successfully warp the textures to look like wood grain which was accomplished by passing the separate red, green, and blue vector data channels through a series of math nodes in creative ways.
I’m not a wizard when it comes to complex math operations on data, but I had a basic idea from other people’s work what to use and I just spent a lot of time rearranging the nodes and playing around until I found something that worked. I think for this project I’m happy that I took the time to learn a bit more about this process as it taught me a lot about the power of getting my hands dirty with low level components and how I could create interesting effects with a little bit of time and effort.
The Studio Lighting
Right about the time I was working on this project I remember watching the recap of the Blender Conference for 2016 on YouTube. Jonathan Lampel had a great lecture where he talks about the basic approach to creating interesting lighting and I remember that going through my head as I was working on developing the lighting for this render. In his lecture he mentions isolating your lights to make sure that each one individually is having the effect you want it to have on your scene. And he also talks about the idea of manipulating your lights to make sure that they show off the forms of your models. Those two things really stuck with me as I was working on lighting this scene.
So for the basic lighting I started with a hi-res HDR panoramic image that I found online. I was just looking for something here that gave me a nice basis to work from with decent lighting coverage and interesting reflections. I then started building up the lighting in my scene by using a combination of mesh emitting lights and Blender’s built in lamps. I tried my best to isolate different lighting effects on separate layers so that I could work on turning groups of lights on and off to check out what they were actually doing to my scene. When you have everything turned on at the same time it’s hard to critically adjust the minute effects an individual light has on the overall scene. So, following Jonathan Lampel’s example, I worked on isolating each light or light group and making sure it was doing exactly what I wanted it to do for my scene.
I made sure to use basic three point lighting principles to give the guitar adequate coverage. This is done by making sure to include a key light, a fill light, and a back light of some sort. After I had those foundations placed in the scene I started adding in different mesh lights and other lights around the guitar to add in interesting reflections and to highlight parts of the guitar that were still underexposed. If you’re going to use this method to light your scene make sure that you turn the strength of your HDR in the world settings all the way down to zero so that you’re not getting any influence from the environment as you work on your lights. It’s easy to forget that and lose track of which light is really being effective.
Finishing Up With The Printing Process
Most people in this industry will never have to deal with printing their work unless they do posters for conventions or end up getting a book deal. But when you start thinking about printing your 3d work instead of just showing it on a computer screen things can get complicated. I’ve had several years of real world design experience having to deal with color on paper so I knew how to navigate these dangerous waters, but it’s never a cakewalk if you don’t take the time to pay attention to the details. So I thought I would wrap this up by talking a little bit about my experience with this project and what to think about if you do any printing of your own.
RGB vs. CMYK Color Systems
The difference between color on a computer and color on paper is that you are using two fundamentally different theories to describe color. Color on a computer screen is made up of light. And to create different shades of color various forms of red, green, and blue light are combined. Because these colors are added together we call the RGB color system an additive system. Adding the most intense values of red, green, and blue together will give you the brightest white that your computer monitor can produce. If you want black on a computer screen you just use less and less of each color.
Color on paper goes by a completely different system. Most of the time when you are talking about printed graphics on paper you are using a processed color system known as CMYK. The letters refer to cyan, magenta, yellow, and black. This color system is a subtractive color system, just like every color system in use in the physical world where pigments of color are combined to give you hue, saturation, and value. The most noticeable difference here is that the more colors you combine the darker the mixed colors look on paper. So it’s the exact opposite effect of what you can expect when adding colors together on a computer.
It’s really important to take the time to understand the basic difference between the two color systems because when you want to take a final render or design from a computer screen to paper you’re not going to be able to avoid a shift in color. Every color in your piece will have a slightly different hue, saturation, and value. And so when it becomes necessary to convert from an RGB color space to a CMYK color space for printing you can expect things to shift and look different on screen and on paper. So what’s the solution?
Well the best advice I can give you while working in the computer is to calibrate your computer monitor’s color to the best of your ability. Usually you can do this with buttons on the side of your monitor or in your operating system’s screen settings. Graphic design professionals even use expensive pieces of hardware that are placed on the screen to match the light output of the monitor to a much higher degree of accuracy. After you have your screen properly adjusted so that you can see as much dynamic range in the lights and darks and the color spectrum you want to make sure that you’re using an accurate color profile in your graphics program. Photoshop allows me to choose several color profiles and attempts to simulate the color shift when I change into CMYK color mode for my render. But this isn’t perfect which brings me to my final point.
Always Proof Print . . . No Matter How Good It Looks On Your Screen
When you finally lock in that final render in Photoshop and you’ve spent hours and hours sorting through dozens of layers and tweaking everything to perfection it can be tempting to just hit print or send it off. This is especially true the less experience you have doing high quality prints on paper or dealing with a printing company. Maybe you’ve been working on the project for a while now and you just want it to be over. Thinking about spending even more time on something you’re not really interested in just seems like too much to deal with. Don’t fall into this trap.
If you’ve spent anytime working on a 3d project then you know what it’s like to hit the render button and find yourself waiting around for the results. I’ve personally waited days for a single frame to render. And when you finally get a chance to see what you’ve been waiting for how many times is it perfect right out of the gate? That’s what I thought . . . never. So you shouldn’t expect anything different when moving from a perfect looking render on your monitor to a printed render on paper. It’s going to take some testing and that test is called proofing. If you’re dealing with a company in person then you should demand as many proofs as it takes until you’re completely happy with the result. Sometimes you may need to pay for additional proofs, but the money is a seriously good investment. And this is especially true the more money you’re spending on the final print. Don’t skimp on this step. Make sure you are getting on paper what you expect.
Even if you’re dealing with an online printer it should be possible to get proofs. And there’s a big difference between digital proofs and physical proofs. I mean the whole point is to see how the final colors come out on paper. So ask for a physical print proof to be shipped to you so you can examine it for yourself. Even if you trust the company you’re dealing with do you really want someone else deciding whether or not your render meets their standards? They haven’t invested hours, days, or weeks in this project so they aren’t going to be nearly as critical as you. So go the extra mile and proof with a physical copy.
For this particular project I had to do several proof prints to get what I wanted. And I didn’t want to spend a lot of money so I went with a local office supply store which shall remain nameless. Needless to say you get what you pay for. If you go to a professional printer then they can speed up the process, speak in a language that will make you feel comfortable about their ability to finish the job, and they are more likely to have the experience to give you what you want. The cheaper services are much more unpredictable so be prepared to get your hands dirty. I had to step behind the counter and do my own color correction at this particular facility so that I got a decent result. Don’t walk out with anything less than what you want. You put a lot of time into getting to this step so make sure you stick it out and take it seriously. Look at every detail and ask yourself if your dynamic range from darks and lights in your print is still there or if it is getting crushed. Are there any major color shifts that you didn’t expect that you need to fix? Did you make sure to output at a high enough resolution so that your details are crisp and clear? The devil’s in the details.
To date this was one of the most successful projects I’ve ever completed. There were definitely some hiccups along the way, but for the most part I didn’t have to scrap everything and start over because I started with a solid plan. Could things have gone better? Sure. Are there things that I look at now and wish had turned out better? Of course. But at the end of the day I was happy with the final result and my dad was ecstatic about having something from me to hang in his office so I accomplished what I set out to do.
If you made it this far then congratulations for getting through my first post mortem! I’d love to hear what you guys think so check out the final hi-res render below and leave me a comment about this project or projects of your own and what you’ve learned. Thanks for reading and if you found something valuable please share this with your friends. Also check out my brand new Patreon page where you’ll find more projects with access to hi-res desktop renders, breakdowns, and some behind the scenes views of my personal work.