[mtripoli]

Even air refracts, although it's very very little. So little it's normally set to 1.0. But i'm gonna be a real nerd now and post the air ior value below.

Air 1.0002926

/ Max

Nerdier question:
1.) Does Maxwell 'calculate' to that many places, or would that be
truncated to 1.00?
b.)I *think* this is kind of important to know and not overlook... I could see how one could make themselves mental trying to figure out why they DON'T have caustics when they *think* they are rendering "glass"...

BTW: jurX did say in his original post "for testing the glass has no ior settings...." so not saying he made a mistake

[Bubbaloo]

Does Maxwell 'calculate' to that many places, or would that be
truncated to 1.00?

I'm interested in this too.
How accurate is Maxwell, hmmm?

[w i l l]

Maxwell has a precision of up to 5 decimal places. Right click in the slot and select 'Decimal precision'.

[JDHill]

Nerdier question: Does Maxwell 'calculate' to that many places, or would that be
truncated to 1.00?

Nerdy question gets nerdy response.

And the anser is: it will do whatever you tell it to do. You can extend the decimal precision out to five places, set Nd to 1.00001, and you'll get a refractive material. It is possible to get a number like this 'stuck' there...say that you have alot of precision in that setting, and you save a material with a number like that - it should not be truncated, since you entered it that way. But...now if you open this material while decimal precision is at something like two places, you have a tricky situation: the number you saved, the one you entered very carefully, is read back in just the way you wrote it - but the UI will hide this from you, and if you render this seemingly '1.00' material, it will still be rendered as '1.00001' - with refraction. But this is also a 'fragile' detail, since now that you have a lower decimal precision, the simple act of giving focus to the Nd textbox, and then moving away will dutifully set the number to '1.00', which is what you are 'asking' for.

Also, in the spirit of nerdy completeness...Nd=1.0 is not supposed to be the IOR for air - it corresponds to a perfect vacuum. Also, in addition to using this value, it is also necessary to make sure that transmittance is also corresponding to that of a vacuum - 255,255,255 white - or in other words, everything is transmitted. Nd=1.0 doesn't mean much if this isn't also true.

[w i l l]

Why not just not have the decimal precision option? Then there's no way of it reverting back to 2 decimal places? If we want 1.82945 as 2 decimal places we just enter 1.83. Surely that's better?

[Bubbaloo]

Good to know, JD. Thanks!

[JDHill]

Why not just not have the decimal precision option? Then there's no way of it reverting back to 2 decimal places? If we want 1.82945 as 2 decimal places we just enter 1.83. Surely that's better?

Sorry, I don't quite understand what you mean.

[Bubbaloo]

Why not just not have the decimal precision option?

We do.

[w i l l]

Sorry, I don't quite understand what you mean.

Well if Maxwell precision was always set to 5 decimal places and had no way of reverting back to 2 decimal places (i.e. when you open Studio on a different machine) then there wouldn't be a problem of say 1.00001 rounding down to 1.

Is that what you meant? - If you open Studio again on another machine/or just re-open it then it'll default back to 2 decimal places?

[w i l l]

Why not just not have the decimal precision option?

We do.

You miss read the 'not' I think. I meant - just have no option to set it back to 2 decimal places. It should always stay at 5 as default.

[Bubbaloo]

Oh, you're right, I didn't see the second "not".
Sorry...

[JDHill]

Well if Maxwell precision was always set to 5 decimal places and had no way of reverting back to 2 decimal places (i.e. when you open Studio on a different machine) then there wouldn't be a problem of say 1.00001 rounding down to 1.

But that is a non-problem, i.e. it already doesn't behave that way - what I said is what happens: if you open a 'more precise' number on a 'less precise' MXST, it will still be rendered using the 'more precise' number. It is only rounded back down to a lower precision when you edit the value in this less-precise environment.

[w i l l]

I know - but why have the option for a less precise MXST? Why not keep precision fixed at 5 decimal places always on all MXST's.

[JDHill]

No clue...put it on the wishlist and see if other users agree, I guess.

[mtripoli]

Thank you JDHill for the explanation!