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the image for explanation

Image 1 is called highlight and 2 is shadow.

I came across them while searching for game effects.

As explained in the image, one is screening, the other is multiplying, making the base blue sphere look like an orb.

I've been trying to re-create image 1, 2 in a way that suits my taste but, all my efforts were for naught. It is beyond the reach of my knowledge and I'd like to get some help from more experienced people for how to create transparent spheres like them.

The only software I can manage to use is Photoshop. But please, you don't have to restrict your solution. If you can solve it via any other software, then I'll look for that as well.

Thanks.

p.s.:

highlight.png - 210x210

This is image 1 in original resolution for your inspection.

UPDATE:

To prevent any misleading, I'll add more info.

I'm asking about how to create image 1, 2. Not how to make a result using image 1, 2.

I'd like to ask how you would create images like 1, 2?

  • You realize the image doesn't actually contain blending modes, correct? The PNG is merely a low transparency image with black and white areas. There's no "multiply" or "screen" in the PNG itself. PNGs can't do that. – Scott May 4 '18 at 9:58
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    @Scott Thanks for comment. Above image contains the phrase "applied as...", indicating my knowledge of blending modes. But I have realized the need of specifying more clearly. I'll edit my question. Thank you. – tennisball99 May 4 '18 at 11:02
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    Sorry if that came off as condescending. It wasn't meant to be. We do get questions around here about people wanting a PNG to be in 'multiply' or 'screen' mode, so I had to check :) – Scott May 4 '18 at 11:05
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    @Scott That wasn't condescending. I knew your intention. Like I said, you made me realize my question wasn't direct enough. Thanks for that. – tennisball99 May 4 '18 at 11:17
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Old school....

It's possible to use Photoshop by laying out tonal values on a square canvas, then using Filter > Distort > Polar Coordinates > Rectangular to Polar

Paint areas of dark and light then the distort filter will create the "orb" or sphere. It takes a bit of experimentation before you get the hang of it.

enter image description here

I've painted everything on one layer here, but you can use multiple layers then merely create a Smart Object or merge the layers before running the filter. Or, repeatedly run the filter with the same settings on multiple layers.

Running Filter > Distort > Polar Coordinates > Rectangular to Polar essentially distorts the pixels by stretching them around a center point. Pulling to top center into the middle of the canvas.

enter image description here

So, after running the filter you end up with sort of an "orb":

enter image description here

You can use multiple layers for highlights and shadows:

enter image description here

Then merely run the Polarize filter on each layer:

enter image description here

Essentially...

  • The bottom edge of the square will be the outer edge of the orb. A hard edge near the bottom helps to better define the final result. The further offset the hard edge at the bottom is, the further the orb will be offset from the edges of the canvas when it is created.
  • The left and right sides will ultimately meet at the top. So keeping the sides as "tillable" or visually similar will assists in avoiding a seam at the top of the orb.
  • The top edge of the square will ultimately be the center of the orb.

It takes a little experimentation but it's not that difficult to gage where things get "stretched" to.

It can also be handy to convert all this to a Smart Object and then apply the Polar Coordinates filter to the Smart Object:

enter image description here

Then edit the Smart Object Contents. This can help show results as things are edited merely by saving the SO contents:

enter image description here

Combine this with Filter > Distort > Spherize on another layer, and some additional layers for "sweetness", and you can get a pretty decent appearing shadow/highlight overlay.

enter image description here

enter image description here

Note that none of the layers in this file use any blend modes. All layers are set at Normal and only their opacity is altered.

All those additional layers could further be combined into a new smart object, leaving a single smart object layer to use as an overlay.

enter image description here


Full disclosure: This technique comes from a time long ago before Photoshop had any 3D capabilities. So, it would not surprise me at all if this could be done much faster and easier using Photoshop's built in 3D features. That's merely not an area of Photoshop I've not felt the need to dive into yet.

  • Nice "mystical" look. – Rafael May 4 '18 at 23:08
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    It was very helpful. Thanks for sharing your experience, Scott. – tennisball99 May 5 '18 at 10:47
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I need to spam you with some of my other answers on similar topics. You have some homework.

How can I make a shape look like it is made of glass?

Inkscape: realistic lighting and shading

Prototype Visualization: How can I learn to render glass convincingly?

For this specific case, the difference vs the other posts is that you have some textures.

Take a nice landscape:

Resample it onto a square and apply filter Spherize, not one time but 3-4 times.

enter image description here

C. Convert it to grayscale. Mask it onto a circle. If you want a crystal ball, invert the image. If it is a glass bubble, leave it upwards.

D. Add some transparent gradient. (you can use a mask) and some blur, in this case circular blur.

E. Add some reflections.

enter image description here

If you simply work on a different layer one can be used for the highlights and the other for shadows...

enter image description here

Or you can take your image, duplicate it and play with levels making different versions of the image.

enter image description here

H. Add blending mode

I. Multiply blending mode

enter image description here


But the truth is that I do not like the simplistic approach of "1 is a highlight and 2 is Shadow"

As my other posts commented, gradients are not linear, they require optical adjustments on the hue.

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    Appreciate your answer. I'm trying both of yours and Scott's method. Using spherizing in this way didn't cross my mind so, I'm having good time messing with various options. – tennisball99 May 5 '18 at 10:51
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Some theory:

An image of a transparent sphere isn't a fully absurd idea, because

  1. Materials are not fully transparent, they absorb and reflect light or scatter it diffusely

  2. A piece of well purified high quality glass can seem to be fully transparent, but it refracts light . That causes "lens effect" ie. it distorts the objects which are seen through the glass

All effects can depend on the wavelength. That appears as coloring. It occurs in several ways:

  • a piece of glass can be colored like other materials
  • thin (1 micrometer or less) films such as soap bubbles reflect differently different wavelenghths and you can see reflections in all rainbow colors.
  • thick glass acts as a dispersive prism and causes color aberration

Enough? Ok, no more theory. Lets see some practical applications. Let's at first have two glass spheres against a black background. One is hollow, it's made of thin glass and the other is full of glass. The glass is assumed only to cause some diffuse scattering (=milkiness), no reflections, refractions nor coloring. In the left we have the hollow thin shell and in the right we have the one full of glass. The light is assumed to be diffuse.

enter image description here

Both are drawn as solid white circles, which are made transparent with gradient layer masks. Linear gradients do not make plausible effect. They are made non-linear with the curves tool. You see the actual non-linearizing curves dialog for the thin shell.

The amount of opacity can be justified by the thickness of the glass just in front of the eyes. The thin shell has most of glass in front of the watcher at the edges, full glass is thinnest at the edges. A mathematician could calculate the right opacity profiles, but these are only my guesses.

These do not at all seem to be partially transparent glass spheres. The glass in the right is far too milky to be seen as nearly transparent glass and all other effects are omitted.

We make the glass in the right clearer and take along some surface reflections. In cartoons we see distorted windows (even outdoors). We try it, too. At first we purify the material of the full glass ball. We make it in the middle about as opaque as the thin version at the edges. Part of the dimming is made with the opacity slider to be able to take it back later if needed.

enter image description here

We draw some rectangular windows. We are going to distort them like they are reflected from a spherical surface. Photoshop's Filter > Distort > Spherize does not do the job because it causes distortion like stretching a flat image over a half sphere.Everything gets bulged outwards from the middle, but the result still isn't curved enough. Double spherize is doubly bulged. We use at first warp and then apply the spherizing.

enter image description here

Extra dots are to make some playground for Edit > Transform > Warp:

enter image description here

This is not curved enough, but Photoshop's Spherize makes it better. With reduced opacity it's acceptable:

enter image description here

The full glass sphere got it's reflection otherwise. Freeware Paint.NET has a fisheye lens distortion filter. The windows were distorted with it. After tweaking the opacities, both spheres are now:

enter image description here

Windows are a cliche. Actually any distorted photo or syntethic image will go as long as it has some apparent lines that seem to be bended to curves in a plausible way.

Another practical must is a bright highlight or several of them. If there's somewhere a bright light, it will bounce in the glass several times without getting attenuated invisible. Finally some part of it hits watcher's eye, often several copies of it.

In the following image both spheres have got a bright highlight - a spot, the thin glass version has also a couple internal reflections. All are painted with a round brush, one clik per spot.

enter image description here

The opacities of the layers needed some tweaks to keep everything well visible.

Everything is about as simple as possible. For me the result is acceptable for demonstration purposes. Real use probably would need richer reflections and highlight spots.

So, the spheres are just acceptable against black background. But when the background is a real photo, the spheres start to look out very poor:

enter image description here

What's the problem and how to fix it?

There are several problems. The easy one is the fact, that the city cannot be as bright seen through the glass as elsewhere, because the glass reflects part of the light off. The easy solution is to make a selection with the magic wand and the origimal "milkiness" layer and reduce the brightness. I added an adjustment layer "curves". The layer mask become automatically after the spheres were selected:

enter image description here

I reduced the brightness uniformly. Actually the reduction should be more where the glass is thicker. The layer mask of the adjustment layer should contain gradients. We try it, too:

enter image description here

Now there are opposite gradients in the layer mask of the city darkening layer. The difference is only just noticeable ==> The benefit of the extra complexity is marginal. We do not use it further.

The adjustment layer isn't good for use, because it cannot be merged into one PNG image which is used as a transparent overlay. Fortunately it can be replaced. Insert a low opacity layer with black solid circles. They are easy to make by selecting the original milky shapes with the magic wand and painting black to a new layer just above the background image:

enter image description here

Actually the result is quite good for the thin sphere, if we assume the glass is ultra thin, which makes lens effects neglible.

Full glass sphere needs the lens effects and some of it should applied also to the thin one just for plausibility.

Lens effects

A full glass sphere rotates the through seen image upside down ad reduces the apparent size. Depending on the refractivity of the glass material a part near the edge can be distorted unrecognizable. If there's some objects very close in front of the sphere or the wiewing point is close the sphere, the refracted image is extremely complex. We skip it. Without smudged edge the image with a full glass sphere is:

enter image description here

The darkening layer was deleted and the darkening was applied directly to the through seen image. That image is a 180 degrees rotated copy of the photo, only warped and spherized and darkened.

Practical full glass sphere wouldn't show the background well near the edges. To simulate it a heavily smudged version was made. Physically it's a total fake, but can create a plausible effect. Smudging is done with Filter > Blur > Radial Blur > Spin. Transition between the perfect lens image and the spinned image is made with a layer mask:

enter image description here

The windows reflections seem still to be ok, but the light spot Isn't. It would need the sun. The spot is deleted. We add the sun later.

The thin sphere needs some distortion at the edges. A piece of background is copied and spherized negatively. It also is physically nonsense, but a different distortion is tried than in full glass sphere. Probably spin blus would have been as good here.

A layer mask limits the distorted zone to be about the same, where the original milkiness is obvious.

Windows reflections work still, but the spot highlight is removed. Outdoors the spot must be the sun or nothing. The darkening is made with low opacity black circle:

enter image description here

The sun creates some flare in cameras, so it must be added, if the sun reflection is included. Here It's a white spot with layer style Outer Glow. A blurred white spot works, too, but the layer style is adjustable. Both spheres got the same sun. To be plausible it must be put to a physically possible place and covering the sharp edge of a close window reflection. Multiple bounces inside the glass are skipped.

enter image description here

The thin sphere can be transformed to soap bubble. Only colorize the reflections slightly with random rainbow colors:

enter image description here

DONE

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