Creating 3D Lentigrams with Blender
A lentigram is one of those ribbed images that seem to move when you rotate them. Here’s a story on how Blender can be used to create them.
My name is Giovanni Remigi, and I would like to show a different use of Blender.
I take 3D pictures that are later printed on lenticular media. I recently finished this project (please watch at full resolution):
I started few months ago using Blender to integrate virtual props into a real 3D picture and to simulate the final result once the image have been printed on lenticular support. The video is an actual physical simulation of the print made with Cycles.
I took the picture of the model with an array of 5 cameras and created a video using several software.
The butterflies have been modeled, sculpted, textured and rigged with Blender. Texture of the butterflies have been hand-painted with Photoshop. The shadow pass and the integration of the butterflies into the final image have been executed entirely with Blender Cycles and Blender Composer.
The 3D image to be printed on lenticular has been generated with a software that I wrote and that is freely available on my website: www.framedlives.com.
I hope you like it,
Giovanni
This looks interesting!
very nice; i also print lenticulars occasionally on large format for trade shows exhibits etc. After creating the 3D content the printer samples the image in slices with specialized software, or did you do that internaly in Blender as well?
In this case I created a video of 101 frames in Blender, i.e. a sequence of 101 TIFF images: one video with the butterflies and one video with shadows only (3 days of rendering in cycles).
Then I merged butterflies and shadows into the video with the model obtaining a final video of 101 frames.
Eventually I loaded this sequence into my own Interlacing Software (http://www.framedlives.com/interlacer) with a bunch of parameters e.g. print size, shooting distance, mechanical pitch, viewing angle, etc.
Finally I printed this image with an InkJet printer on paper 13″x19″ and I laminated the result on the lenticular lens.
The simulation you see here has been obtained applying a virtual lenticular lens over the actual interlaced image: what you see here is a 40LPI lenticular lens, 13″x19″, with a 25deg viewing angle.
I usually create 3D portraits, only recently I’ve started using Blender to add additional elements not existing in the actual picture.
I’m working with portraits, but a 3D lentigram can be entirely generated with Blender, interlaced with a proper software and printed on lenticular media.
If I use your program and I want 101 frames, what LPI lens would you suggest for an 8X10? Will this software figure it out for me? Or does it just interlace it for me?
I assume you mean 8″x10″?
If you want depth, for that format I would go for a Micro Lens 3D 40LPI lenticular sheet with a viewing angle of 25°. But the comfortable viewing distance for that lens is roughly 1.5m away. Good for something that hangs on the wall.
If you want less depth but a comfortable view even when the print is handheld, I would go for a Lenstar 3D-50LPI lenticular sheet with a viewing angle of 41°. Good for smaller formats too.
My software is just an interlacer: you give the set of pictures, the lens parameters and few others and it generates an interlaced image selecting the correct subset of images that should be printed under every single lenticular lens from a specified viewing distance. It is to create lenticular pictures where width, height and depth of the original image are maintained on the final print.
It comes together with a pitch test software to measure the pitch of a lenticular lens in relation to your inkjet printer resolution. They have to be used together to get correct results.
yeah I meant 8 inch x 10 inch.
And an inkjet printer will do? The dot pattern creates a quality print?
I think mine is 9600×2400 dpi. How do I know what the true dpi is? Is it the 9600 number or the 2400 number or is it something different altogether?
What is important is the actual PPI, not much the DPI. The PPI gives you the amount of images that you can put behind each lens.
For what I’ve learnt all Canon InkJet printers have 600PPI, all Epson printers have 720PPI and all HP 600PPI.
I have a Canon 9500 Mk II and on a 40LPI I can print 600/40=15 images. When using InkJet printers on lenticular is mandatory that you print at the native resolution of the printer (see above) otherwise the printer will do it for you behind the scenes and you are likely to destroy the final result.
Many people use Epson because with a PPI of 720 they can get a better result.
As far as I know, with Epson you can better control the dot pattern adding some error diffusion in order to remove the Moire effect, but I’m not able to do this on my Canon so far.
This is still a big research field :-)
Sorry if I sound like a dumby but I thought you said you had 101 frames which = 101 images? But then you say you can only do 15 images? So can you do 1/2 a second of animation or little over 3 seconds of animation?
This is a common question actually :-)
Assume you are using a classic interlacing software and you want to print on a 40LPI lenticular sheet with a 600PPI resolution printer. Iwth a classic interlacing method, in this scenario, it is enough to have 15 pictures. Behind each lenticular lens you would put a line from each of the 15 pictures.
The classic interlacing algorithm doesn’t consider the viewing distance and, in portraits, cause a visible deformation of the subject.
If you add the viewing distance into account, behind each lenticular lens you have to put a portion of the original image that would be visible at the specified distance. With only 15 pictures you don’t have all possible viewing points, so that’s why I use 101 in my case. From this video of 101 frames the software will select the correct frame and the correct vertical line of that frame that is visible from the specified distance and it will use that line to create the interlaced image.
This will remove the horizontal distortion. This procedure is important for portraits because our brain is very good to detect problems in a person face especially if it is the face of a person we know.
The problem is less problematic in other scenario so the standard interlacing software can be used.
Not sure if I was able to explain the problem. This is not an information that you can easily find on Internet. I’ll see if I can post a comparison between the two methods.
“This is not an information that you can easily find on the internet.”
Absolutely true! I’ve been looking into this particular matter for a few years but I gave up with lack of information and the old schoolers telling me it wasn’t possible with inkjet printers.
So basically you are saying that you use 101 images so that your program can select the best “section” of each frame so that your lenticular print doesn’t end up looking like a Picasso (which could be super cool but not for clients paying for a 3d portrait)? So the end product is the best sections of 101 frames totaling .5 seconds of animation?
I’m excited now. Someone willing to share their lenticular secrets.
With inkjet printers is absolutely possible and you get very good results too. What you see in the simulation that I posted above is what the final print really looks like and it is 100% accurate. A 13″x19″ (A3+) picture printed on a 40LPI lenticular sheet with a Canon 9500 mark II at 600PPI. Printed on high quality Canon paper and laminated on the lenticular sheet.
In lenticular there are two main markets: 1) high volume and low price that is dominated by lenticular printing companies with expensive offset printers; 2) low volume and high price that is obtained either with flatbed or inkjet printers.
In this two markets there are very few people who are willing to share their “secrets” :-)
To me it looks more difficult than it actually is and I’m quite surprised that this media is used so little in the 3D field e.g. to showcase your 3D work.
Back to the software, search in Internet for something called “Light Field”.
The problem is summarized in capturing multiple rays of lights coming from an object from different directions (with multiple cameras or with a 3D software) and then print them back (properly) into a lenticular sheet. It is a pure geometrical problem.
This is the comparison between the two interlacing algorithms. As a reference the original image straight from the camera.
So using the 1 blender unit = 1 meter or 3 feet is actually a big deal with this style of printing? Thanks for sharing all of this with the community!
I have found that people definitely do not like sharing what they know about lenticular printing–or they offer their software for ludicrous prices…if only someone would step up to the plate and make their software open source.
Interesting! The http://www.framedlives.com is bad btw > http://www.blendernation.com/www.framedlives.com
fixed, thanks!
2 x thanks
Blender is cool! I bet it was nice not having to pay for blender when developing your software–I just wish there was a lenticular printing program that was also free, but alas. Full featured software all has a going price of 500 bucks or more.
Does anyone know where I can get sample blank 3D sheets. I thought I’d give 50 and 60 LPI a go.
I see some suppliers only sell in packs of 100 and I am no where needing thos quantities.