By modelling the axis ratio distribution of SDSS DR8 galaxies we find the intrinsic 3D shapes of spirals and ellipticals .
We use morphological information from the Galaxy Zoo project and assume a non-parametric distribution intrinsic of shapes , while taking into account dust extinction .

We measure the dust extinction of the full sample of spiral galaxies and find a smaller value than previous estimations , with an edge-on extinction of E _ { 0 } = 0.284 ^ { +0.015 } _ { -0.026 } in the SDSS r band .
We also find that the distribution of minor to major axis ratio has a mean value of 0.267 \pm 0.009 , slightly larger than previous estimates mainly due to the lower extinction used ; the same affects the circularity of galactic discs , which are found to be less round in shape than in previous studies , with a mean ellipticity of 0.215 \pm 0.013 .

For elliptical galaxies , we find that the minor to major axis ratio , with a mean value of 0.584 \pm 0.006 , is larger than previous estimations due to the removal of spiral interlopers present in samples with morphological information from photometric profiles .
These interlopers are removed when selecting ellipticals using Galaxy Zoo data .

We find that the intrinsic shapes of galaxies and their dust extinction vary with absolute magnitude , colour and physical size .
We find that bright elliptical galaxies are more spherical than faint ones , a trend that is also present with galaxy size , and that there is no dependence of elliptical galaxy shape with colour .
For spiral galaxies we find that the reddest ones have higher dust extinction as expected , due to the fact that this reddening is mainly due to dust .
We also find that the thickness of discs increases with luminosity and size , and that brighter , smaller and redder galaxies have less round discs .