Lots to talk about.

Most important, welcome to the forum.

For your scene, you have lots of options.
Here are two that come to mind.
1. take the video game level rout: Place other lights in the room to simulate bouncing photons. I'm sure you thought of this and don't like this practical idea. That's ok. I don't either.

2. Use Mental Ray "Final Gather" options to make your light photons bounce. If you're using default scan line, enable "light tracer" under "Advanced Lighting." For both add to the number of bounces. You can also dial up some of the other numbers, on both renderers, to add more photons.

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thanks isaacq for your quick response!
i tried simulating bounced light by calculating radiosity at 80%, but i seem to encounter problems with some of my meshes...for example, the back of the computer-chair starts looking like a bad, huge noise map applied to it, and so do the walls (which are just boxes really)...any reasons for that? i tried enabling and disabling the mesh subdivision
i intend on rendering with mental ray (the pic i posted was scanline) but i think for that, all your materials have to be mental ray, right? have never used mental ray before... i thought some preparatory steps had to be taken before using it... will try it in any case....and is 'light tracer' suitable for indoor environments?

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Cogito, Ergo Sum

I use standard materials with mental ray and don't have any apparent problems.

I always thought radiosity was a pain in the butt.

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Chris

i just tried light tracer.....i have no idea what's going on? what are all those little spots doing in the scene? will give mental ray a go now, but can someone please explain this picture? i tried bounce value of 2, and there are spots everywhere!

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Cogito, Ergo Sum

your ray/sample number is too low. Raise it by 200.

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Radiosity in max works very differently than you would expect and you need to model your scene with special consideration,i just avoid it because you can get much better results with mental ray or other GI renderers. With photometric lights you will probably have to use exposure control if you want to use real world values and even then I usually find myself cranking things up to compensate for attenuation.
You can use standard materials with mental ray but there are some nice options inside some mental ray materials. When you are adjusting GI lighting you will want to adjust the brightness of your materials and sometimes even override the colours to avoid things like very strong colour bleeding.
You can try doing things like having one very white wall behind the camera so that GI bounces more inside the room.

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Also mental ray is a multi thread rendering system while default scanline is only single.

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so you mean that whenever real world values are used with photometric lights, the result is not true to life? or rather, there is too much attenuation?
and i can't have the white wall behind the camera because there is a door there (unseen in the pic) and there are cupboards also.... can you tell me how light tracer is used? am trying out mental ray now.... will post results

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Cogito, Ergo Sum

here it is....i switched to mental ray renderer... enabled final gather....didn't improve the lighting much (the room was still dark) so i put on some exposure control, hiked up the brightness and here's the result (below)..
but it's still not exactly what i'm looking for...i want the light from the bulbs to spread much further than it is, and light up the room on its own.... they are pretty powerful lights (in real-life!) .... any changes i can make with the final gather parameters? i've set multiplier to 2.0 in both final gather as well as global illumination....but besides that i know nothing about mental ray!
P.S. isaacq, just read your post....raise it by 200???! will give it a shot!

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Cogito, Ergo Sum

Get rid of the exposure control.
For Final gather to increase the light: Right next to the "Enable Final Gather" checkbox adjust the box "Multiplier." Raise it, a little at a time, each render.

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did what you said, isaacq....you're right it's much better than throwing on some brightness.... but the thing is, to get the illumination necessary, it took the multiplier upto 15.0, and i feel sort of guilty raising it this high, (conditioned, probably)... am currently doing a medium-quality render at decent resolution, will put it when it's done.... btw, what does the "diffuse bounces" field do? i've set it at value 1, and the remaining parameters are set by the quality preset 'medium', except for multiplier, which is at 15....

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Cogito, Ergo Sum

Based on my experience, it allows your photons to saturate with the mesh better. It doesn't mean bounce more times around. Which is what most sites claim. If that were the case you could get one light to illuminate an entire building if all the doors were open.
This setting is tied to "rays per FG Point" and "Interpolate Over Num. FG Points." "Diffuse Bounces" is only visible if you have these other two settings on a high number. Normally the difference in this setting is hardly noticeable.

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Not being much of a mental ray person I'll add.
It looks really nice so far. I think maybe using area shadows on the lights would clean up all the criss crossing shadows making them blur out further from the light source.

I don't actually use exposure control often I just mentioned it as a way to get real world values to actually light the scene.

I don't think you can ever just plug in real world values and get what you want except for with Maxwell.
you usually need to compensate somewhere, increase light multipliers, GI multipliers, Object GI generation, amount of photons on the lights, brightness of materials etc.
also, If you can't see the objects behind the camera in reflections you can always hide them and place a white reflection card to boost the reflected light.
like what photographers do in the real world.

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I also noticed if you go into your light object under "mental ray global illumination rollout"
uncheck automatically calculate energy and photons and check on manual settings then raise the light energy for the light.
Seems to brighten things up.
that way you can avoid bumping up the multipliers in final gather and GI.

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ah! that seems a good way to do things...in fact i was fiddling around with individual light energy values in that 'mental ray GI" rollout, but it didn't seem to make a difference...no wonder...the automatic calculation was on...
anyway i thought i'd post my progress so far....i've managed to get some decent illumination going, but at the cost of shadows, and some strange things happening to some materials! i must've used architectural materials without realising the consequences...
anyway will try your suggestions, Tyson
and isaacq, that 'interpolate over num fg points' i found made a huge difference to the way the final rendering looks....a low value of this leads to some splotchy (if that's a word) patterns of light on the walls, whereas a high value produces a nice clean finish...
[still working hard!]

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Cogito, Ergo Sum

Use the splotchy patterns when you want a fast render. That's useful when you have a large project to light and you don't want to wait an hour to test the lights. I like it

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also, is there a way to make the photometric light's hotspot sort of fade gradually, instead of sticking out sharply like a halo? with standard lights, you can control the attenuation etc but i don't know how to do that with photometric....

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Cogito, Ergo Sum

Turn the lights down and turn up the mental ray settings. You really just need to be worried about the bounced light.

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Also, You could try the following ideas.

1.Try playing with web distribution and use an ies file to get some nice shapes of light on the walls. IES files can be found in the max sceneassets>photometric folder (on the C drive). and can be loaded in when you change the distribution type to web and go to the web parameters rollout.

2. Try to increase the contrast of your image by using ambient occlusion. You can use it via the ambient occlusion light shader on each of your lights. or if you are using the arch design material you can use it inside the material. or you can use it as a render pass by creating an override material with an ambient occlusion map in the self illumination slot and turn all the lights off. then multiply this render over your diffuse pass. former two options will give you a better result though I believe.

3. Use some gamma correction to increase the brightness without effecting your black and white values. Using gamma correction in post on a high dynamic range render (open exr for example) is a good way or you can change max's gamma settings. Gamma of 1.8 is apparently similar to photographic film so it can give you much better realism in your renders when using GI. Rendering to .openexr and upping the gamma in photoshop is a nice easy way to improve your render without messing with max's colour mapping or exposure control.

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x2

By the way, desade2009. Get your avatar situation straightened out.

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wow, Tyson those are some very detailed suggestions thanks! will try each one out and see if it improves the scene! although the third one i don't quite understand... you mean to say the file format i should render to is .openexr? and where do i set these gamma correction values?
will definitely try out ies files, because i am looking for good light shapes on the wall instead of the halo i'm getting now...
and isaacq, by avatar you mean the teapot image next to my id? that's what i think avatars are... other than 'avatar', a sanskrit word meaning 'alternate form of life' probably the same thing....!

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Cogito, Ergo Sum

P.S. I am trying to go for non-photoshopped renders! Something in me says don't cheat! of course it isn't cheating i know but still.... i'll keep it as a last resort! (upping gamma values in photoshop i mean)

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Cogito, Ergo Sum

Yeah the openexr format has alot of extra options and you can adjust the exposure of your image very well in post using it but make sure you save to 32bit float. If you have photoshop cs2 and above I think it is supported. In the max frame buffer it will render as normal but when you open it in photoshop there will be an exponent applied.
you then go to image> adjustments> exposure and mess with it a bit.
You can also open an openexr image in RAM player and it will give you a small dialogue where you can change the exponent, black and white points etc.

Its not really cheating to use gamma correction in photoshop but I get what you mean. you could do it in the max preferences too Customise>preferences>gamma and LUT.
There may be a way somewhere in the mental ray settings. I know vray has some colour mapping options in the render dialogue. but I can't find them in mental ray as yet. Just don't ever do it in two places at once.

You can find loads of free IES files from lighting manufacturers. this one for example. I havent looked at these but they sound interesting.

[Link to www.antiquestreetlamps.com]

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i tried out some ies files from some manufacturer sites Tyson, and though they give me some cool patterns on the wall, the room remains dark if i don't put in a high final gather multiplier (which i'll keep as a last resort along with gamma correction) which leads me to the initial question of whether my scene is actually in scale...i have my doubts because i changed the system units setup from 1unit=1inch to 1unit=1cm.... that must've somehow screwed something up because even when i download manufactured 100w, 250w incandescent lights the overall illumination doesn't improve....
what i'm now trying is to add the "light point (base)" map as a light shader, and this allows me a great deal of control over the attenuation etc, but i'm wondering if that defeats the purpose of a photometric light....
and tyson, how does the ambient occlusion light shader work? do i need to tweak it?

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Cogito, Ergo Sum

The way to check your scene scale is to create a box roughly the size of your real world room.
then create a dummy object and link all of your objects cameras lights etc.. to the dummy.
scale the dummy so your scene is roughly the size of your box primitive.

I usually use ambient occlusion as part of a material or use it as a seperate render pass. I havent really messed with light shaders much
but I thought it could be a quicker way to include ambient occlusion than rebuilding all the materials.

I think the main reason I have ever chosen photometric lights over other options is the IES web distribution thing. but I guess if you are working with real world units and light fittings you would want to use them to test how many of a certain light will be needed in an interior. unfortunatley everytime you do this it turns into an exercise in tweaking a million different settings and the real world thing goes out the window.

If you really want an experience where real world values have a tangible effect and realism is the primary thing in the render. give Maxwell render a try. Its very slow but loads of fun when you get passed the differences. you can forget about GI, photons, final gathering etc etc.
and focus on, light watts, shutter speed, and fstop values. best of all you can change all these settings DURING the render which is very awesome.

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this Maxwell renderer sounds pretty cool will give it a try definitely...do i just download it? or...? i've been toying with these parameters so long it's driving me crazy!
here's my progress so far.....i've been toying with these parameters so much it's driving me crazy...
take a look at the photo i took of the room (with lights on) and tell me how far away i am from it!
and yes i totally agree with you if photometric lights need tweaking to resemble real-life then the whole point is lost... btw the pic still needs work but i just want to know if i'm any closer than i was

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Cogito, Ergo Sum

the shadows are better in this one....tell me what you think

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Cogito, Ergo Sum

Great image, there's heaps of detail and it's pretty accurate too. What's the shadow on the bed from? It doesn't look quite right.

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[Link to www.3dprevis.com]

Looking good dude. It would improve it loads if you used area shadows on the lights.
Also getting some detail into the materials for the walls like subtle specular variation and some very small bump. plus ambient occlusion so the corners have a bit more weight to them if you know what I mean. Arch and design mat would work well.

Also you could add that square cornice section at the top of the wall to break up the hard edge between wall and ceiling.

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thanks loads gustave and tyson will sort out the shadows.... and yes the room isn't finished yet it's only about 80% done...even the floor i just threw on a 'tile' material just to see how it looks...will put in the cornices, add some slight bump to the wall, maybe a little dirt also i haven't got the hang of ambient occlusion yet tyson....
i got maxwell from a friend of mine, and spent the whole first half of the day reading the manual and staring at the jaw-dropping renders in it...i was hooked....read extensively about materials etc in it...then read the manual for the Maxwell 3dsmax plugin...was even more awestruck by the renders!! and its inherent support for 3dsmax! Then, in all excitement, i revved it up, with my magnum opus scene, changed the renderer, and hit 'render' prepared to be floored..... it then brought up thousands of warnings that the material types couldn't match, and errors about bitmap format....i spent half an hour sorting out the bitmaps (it couldn't read psd) and hit 'render' again, it resulted in an abomination which nearly made me cry! knowing i don't have the time to make those hundreds of materials again for maxwell, i resigned myself to mental ray, and facing the music!

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Cogito, Ergo Sum

Personally I use the ambient occlusion map as the mask in a mix map. mixing black or brown into the colour map. That is to say. Put mix map in the diffuse. colour 1 gets your diffuse map. colour 2 gets black and the mask slot gets the ambient occlusion map. In vray its vray dirt map. them you might want to turn up the ambient occlusion to something higher like 64 so its smoother.

Regarding Maxwell. yeah its a totally different approach. you HAVE to model to scale
because things like depth of field are on all the time. if you model a room the size of a dolls house it will look small due to the depth of field you get for free. Plus all the materials have to be maxwell although it will do an auto convert for all your standard max materials at render time. and you don't use lights at all. you have to use emitting objects. usually planes. you add emitter material properties with the maxwell material. The maxwell material works so that every type of material you create is actually reflective and it takes a bit of a mental shift to start getting succesfull materials. If you take a look at the maxwell render forum there are some really clever guys on there that have worked it all out. They go on about it as if they were in a physics lab. very interesting stuff.

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ah i see what you mean about ambient occlusion.... will try a)putting it as mix map in the diffuse slot for the walls alone, or b)putting it as a light shader (which will affect the whole scene)...
anyway, yes i see maxwell is a completely different approach.... and the auto convert isn't the way to go i think....will have to maybe just model in 3dsmax, and from the materials stage onwards, use the Maxwell renderer in both the final render as well as the material editor... the auto convert really doesn't do justice...a lot of my materials are multi/sub-object, with specific UVW mappings.... i think i'll give maxwell a shot for my current scene...i estimate it'll take me about a month to reconfigure (or remake) the materials for maxwell but it might be worth it right?

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Cogito, Ergo Sum