> if I were you I'd leave it as it is, because it
> looks fine here.

I like my images to look good on every monitor out there. Personally I
think, better too bright than too dark. That way, everyone will be able to
see it, and usually I don't notice when images are "too bright". Anyway
it's usually possible to find a "perfect" balance, but that's not just a
matter of gamma-correction. Gamma correction is important but cannot fix a
rendering that isn't built with consideration of contrasts.

My guess is, the histogram shows a good spread of luminance because the blue
ground statistically covers up for the lack of contrast in the speaker.

It's tricky to achieve good looking, black materials, even more so in
computer renderings. But a good starting point would be to find some
reference photos of black things (possibly speakers) and work from there.

Alex suggested "using more brightness at the radiosity, giving textures more
ambient, using lighter colors, or adding more lights". I wouldn't do that,
except perhaps "adding more lights" but they should to be carefully
positioned. There are many approches to it, but here is my suggestion:

Turn off radiosity. You can activate it again later, but it's not strictly
needed. For an image of this kind of complexity (where there is only one,
or maybe a few objects in focus, in an empty room) you can usually fake the
radiosity without too much trouble. Doing so gives you even greater control
over contrast and highlights. But even if you decide to turn on radiosity
again, it's a good idea to first position your light_sources, and ensure
they work well.

There are many interesting things you can do with just the light. I won't go
into details here but you decide the mood of the image with light. For
example you can make it look "intense", "warm", "cold", or "natural". But I
assume that for now you'd like people to concentrate on the speaker itself,
when they see your image. You'd like to draw peoples attention to the
design and modelling of the speaker, rather than the enviroment.

So let's use something alone the lines of a "three point lighting system".
You can read lots about it, various places on the Internet, but here is a
simple approch:

The first light you set up, should be the strongest (brightest). This is
called the "key light". I suggest you position it to the left of the
speaker, let's say about 3 meters away. That should be well outside the
camera view. Then you can experiment a little, by moving the light in the Z
direction until you think the shadows from the speaker have a nice
"shape"... I would suggest moving the key-light in the direction *towards*
the camera, so it shines on the front of the speaker, still to the left...
The code should look something like this:

light_source { Position, Colour
    fade_distance 1 fade_power 2
    area_light { 3*x, 3*z, 4,4  circular orient }

I haven't tested but I hope it works. As you can see, I made it a spherical
area_light because I think, a soft shadow would be most flattering to the
speaker... You can adjust the softness to your liking. But fade_distance &
fade_power is best left alone... The colour should be white (or whatever
you desire) but you will need a value that goes well beyond 1.0. Try 50,
100, or more. This is due to the realistic fading I activated.

By the way, if you haven't done so already I suggest you add this line to
the top of your scene: global_settings { assumed_gamma 1 }

On my computer (and I assume lots of other standard PC's with a standard
installation of POV-Ray) this will result in images that use a standard 2.2
gamma correction. If you don't add this line, your rendering will probably
not use gamma correction at all !  Well, it's a long and confusing story.
But lets leave it at this.

Now, after specifying the assumed_gamma, you will probably have to adjust
the blue ground and the black materials, well ALL your materials, but it's
worth it. Another thing that is quite important, is that you should use
"ambient 0" in all your finish statements. Because you don't want the
speaker to EMIT light. Ambience is an old feature from the time when
computer were much slower. Today the feature is rarely used except for
objects that we want to EMIT light.

Back to the key-light: When you are satisfied with the position of your
key-light, the shadows it produces, and the intensity of the light - it is
time to turn it off temporarely, and start adding a so-called "fill light"
or two.

Basically you are using the same procedures as above, but position the
fill-light to the right of the speaker (opposing the key-light). Make it
more dim, and with much softer shadows. Try to make it look like, you're in
a room only lit by a large window, late in the evening. In such a room,
there are no highlights, just soft, dim light that bounces around the
walls. This is the mood you're after. Eventually you can add a colour to
the fill-light ..brown or blue.

When you are satisfied with the fill-light, turn on the key-light again and
see if they both work well together... Still satisfied? Good.

Now, it's time to fake the radiosity by adding another fill-light. But this
one will be placed beneath the ground, and in front of the speaker, so it
will give the impression that light is bouncing from the ground, up onto
the speaker. To achieve this effect (having a light_source beneath the
ground, without being blocked by the ground) you need to use a "light
group". It's very simple. You want the speaker and the ground-light wrapped
into a "light group like this:

light_group {
   Speaker_Object
   Ground_Light
}

Again you can adjust the intensity of the ground-light, the colour and the
soft shadows to your liking. If the ground is blue (as in the image you
posted earlier) I suggest you make the ground-light blue. Don't hesitate to
experiment with the position of the ground-light...

Well, I would be interested in seeing the rendering after this. There are
still a few things to do, but I realise this post is already too long and
I'll stop writing now... I hope you can use it somehow, for inspiration, at
least.

Regards,
Hugo

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