How to increase the contrast (edges) with glass obects? [with IMG]

[donelgreeko]

Hi!

It's normal, because it has no "real border" to the background because it has the same color.
Try a fresnel shader in the transparence Mode or take transparency on <~90%.

[Per-Anders]

Well right now your sphere has nothing behind it to refract but your floor, and nothing to reflect but a basic horizon and sky object. Without those things it will look dull, you need to give it something to reflect/refract, be it a hdri, or some objects around the scene, glass is a reactive material, on it's own it's next to nothing.

You can also drop the transparency slightly, nothing in real life is 100% transparent apart from a total vacuum, glass generally varies from completely opaque through to about 98% transparent, though hat can go up if you're dealing with very thin glass. if you want to fake things you can place a second material on your object applieed to the back faces only, just to give a different color refracted through your glass object, you can also add in small particulates for bubbles and so on.

[mattjakob]

actually it has HDRI :)
could you teach me how to add bubbles and the material to the backfaces ?!?!

THANKS

[Per-Anders]

Looks like your HDRI isn't very HDRI then, has it been converted to a non HDR format such as jpeg or png?

To apply a material to a backface just apply the material and in the texture tag options you will find the control for what it is aplied to, default is set to both.

To make bubbles just create and duplicate a bunch of small spheres with your glass/bubble texture on them then randomize their position/scale (within your main object). There are any numbers of ways of doing this, from particles, Mograph, TP o just using the basic cinema duplication and randomizing commands.

[mattjakob]

uh sorry, but how do I apply HDRI correctly ?
What I did in my scene was to apply a .hdr image to the environment channel.... cant you see the reflactions in the upper middle of the sphere? :)

[Per-Anders]

To apply a HDRI image correctly the environment channel is fine, but you can also just place it in the color or luminance channel of your sky objects material and it will behave a bit more realistically with regards your reflections/refractions, don't try to convert the file type from HDR or EXR to anything else, if it's come in a format other than those two (or possibly TIFF or PSD) then it's not high dynamic range, so you'll only be putting in an image that is standard dynamic range, and you wont get any of the benefits for your reflections/refractions as a result such as the increased contrast and bright/dark points, here it looks like your HDRI lacks any range, where there should be a bright spot from the sun there is none, so you may as well just use a normal image to get the same result. If that's how yoru HDR came then you might want to consider using another HDR image, or you can try to fake it by seting it's mode to multiply then bringing the brightness up a great deal, however that doesn't add any more information to the scene and often results in a very banded and overly saturated effect.

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