Compass Stereogram - Evolution

[morphonius_821]

The 256 shades of gray provide the depth information to the stereogram creation software.

Quite a quaint restriction... but one that makes things very interesting i bet.
(I find its often the constraints that make any pursuit interesting...and when it comes to any art-form: also in a way also define it.)

That would give you a 3-dimensional "contour-scape" of 256 levels...is that right (making up my own terms but i think you get me...)
It that a sufficient resolution do you find?
how does this system go modeling complex shapes do they end up looking like they are built of lego?
I mean obviously shapes that are made up of flat panels are easiest to create...

Can you also just as well create complex curved 3D solids?
How do these come out? (what are the limitations in this respect)
Thanks DAvid

[gwpriester]

Your confusing resolution with depth. The resolution can be anything from screen resolution to 600dpi and above.

256 is based in 8-bit color depth and actually is more than sufficient.

[morphonius_821]

No that is exactly what i meant: the resolution in the 3rd dimension...
The depth resolution...

And if the input image (The one that defines the depth) can only be a 255 colour grey scale then im guessing the z-resolution may well be 255 z "pixels/blocks/possible positions etc... deep)...
But if this seems enough then that's ok.
Perhaps 255 steps is enough and the rest are interpolated if necessary...but i think its more likely that more than 255 steps is not required generally...
Although i was hoping this limitation was not inherent in this software...

you probably wouldn't notice if you were constructing designs made up primarily of geometric shapes as sloping planes would cut-across these levels and this 255 step z resolution would be insignificant but if you were trying to model very complex shapes then who knows...
This is why i asked.
I admit confusion but definitely not on the issue you suppose.
Anyway i will eventually discover this for myself confused or not.

[Soquili]

Hi David,

The 255 levels of gray for the depth information is to make it easier and quicker to calculate.

I once tried a program that calculated 24bit colour. After 3 days and 14 hours it was finished.

[morphonius_821]

thanks for that...
sounds like some serious number crunching is required.

perhaps 255 is a good place to start...
And thanks gary for your input (as the stereogram veteran)... my apologies if i came off defensive...I guess i hate being ignorant about stuff...

One other thing if I have not worn out my welcome...
Can anyone tell me why it is that it seems common to repeat the image horizontally repeatedly (more than 2) right the way across the screen...
Im guessing this is to aid in further masking the hidden content as only 2 images even though only overlaped a few inches and blended into the pattern hash etc may stand out a bit still from the surrounding "noise" so the repeats help mask this a bit?
Is that the reasoning behind the repeated repeats? (just a guess....?)

P.S Also i have started the art for my first stereogram (i don't even know how to use the software yet)...
But now that i know how the depth information is generated i am digitizing the depth information of my subject in B&W (A 2d subject) which is very challenging...
i.e it could work out awesome or perhaps a disaster I don't know as there is probably 50 or 60 hours of work just in producing the depth map.... fun though i love manual stuff...and the mental gymnastics required to visualize the subject sliced up a-la a "cat scanner" is really the fun part...

but im thinking i would like a radial halo effect behind the finished stereo gram like a radial fill" lighter in the middle then fading out to normal to make the image pop a little bit extra when viewed can this be easily achieved too? Perhaps using a transparent gradient object behind the stereo gram, can this be done?

[gwpriester]

The number of times the background image repeats can make it easier to bring the panels together.

If I work really hard, I can see a two panel image. But it really strains my eyes. 3 repeats is easier. 4 easier still.

For an image that is 10 inches wide, I use 5-8 repeats. 7 repeats being the most common.

For a poster that is twice that size, I will double the number of repeats.

[morphonius_821]

I tried a preliminary render of my project and it was woeful...
But i got the idea...I think i tried to be way to technical for my skill level but anyway i haven't given up yet...

I would love if there was an easy app available to generate the depth map...
Ie if you could feed photo into it and rotate at any axis.

Then if you could place mesh points on top like the illustrator mesh tool and drag out ETC...
Then rotate the plane angle to observe the 3d effect.....
I.E you would be able to drag out the z axis of any node and then adjust its bezier nodes to control the scape...
IE like pushing up tent poles underneath a draped fabric ETC...
Then when successfully done if you could output the depth map in black and white ETC....
Can the stereogram generator do this?

[gwpriester]

You would have to generate the depth map in a 3D application.

There are several websites where you can get free 3D models such as 3DXtras Stereographic Suite can open 3Ds files and a few other formats. You can rotate the models in the Modeler module.

There are a ton of user provided 3D models.

Because I publish a lot of my images I have to steer clear of someone elses depth image. Plus I prefer to create my own.

[morphonius_821]

Thanks for that....Failing that (creating the depth map in a 3rd party 3d App)...
Another idea i had was "sketching" this in 3D with very rough spheres and cubes and cylinders etc but i think the 3rd party app may be the way... ill take a look.
However like you i could never utilize someone else's model...the fun part is that you yourself done it.
Is there a 3d modeling software program that you would recommend as being your choice for this type of work..i.e best suited (in your view) to this application i.e. stereograms?