If, for example you wish to test this, enter your location and time for high noon (sun at 180 deg angle) and check daylight savings if necessary.  The angle of the sun in plan (azimuth) will appear at 180 degrees but the azimuth/altitude reading given in the upper region of the Control Parameters won’t correlate.  We are working on a high rise project at the moment where we are required to supply this information to the client and noticed the error when we used an online sun calculator to verify the reading given by max.  The physical sun location is correct but the corresponding azimuth and altitude readings are not. To get the correct azimuth/altitude readings you have to turn off daylight saving time when it is required (eg. june) and turn it on when it’s not required (eg. dec).  Of course when you do this the sun changes position.  It seems that it works in reverse of the way it should.
I have read somewhere that autodesk do not stand by the accuracy of the daylight system but actually it seems that it’s physically spot on.  It’s the quoted azimuth/altitude values that are incorrect.
Can we get this bug fixed?
The accuracy of our shadow studies are sometimes quite critical?  Can we have the final line on whether or not Autodesk stand over their software in this regard?

This is a pretty serious bug. The software is not updating the values in the Azimuth and Altitude values. It will replace the correct values with incorrect values if you switch to other tabs and come back, without changing any information! If you check the values against ecotect you will find that the daylight savings time checkbox is indeed backwards. No check means on, checked means off. There was a white paper validation study for daylighting completed not that long ago that was done very thoroughly… why was this not addressed? I do a lot of shading and sun studies and have recently been using max for it’s visualization abilities. Now I have to double check work in ecotect to make sure it’s correct which is obviously less efficient. can anyone confirm this is on the know bug list? I am using Max 2009 Design.

Actually the azimuth and altitude value lag behind when you’re changing the time in the daylight settings. Try clicking on one of the “up” or “down” buttons a few times and watch what happens… the azimuth and altitude remain unchanged on the first click, then on subsequent clicks show the values for the PREVIOUS setting, not the current one. This may be why the daylight saving button appears to work in reverse. Switching to a different tab and back again appears to make it show the correct values.

The azimuth/altitude data in max is just a hoax, not trustworthy. If you this data is critical for you, check another source.

Example: Max 9, location Vienna Austria
Azimuth/Altitude 185 to 65 (if you check and uncheck the Daylight time saving box you get another data)
03.21.2009, 12:00
Latitude ( 48,2) Longitude (-16,3666)

Max 2009, same location
Azimuth/Altitude 185 to 53
Latitude ( 48,2) Longitude (16,367) – the conversion is made between Max 2008 and 2009, in version 2009 the system is turned upside-down
Between all versions of Max (5,1 to 2009 are the one I tested) there are small differences although the position of the sun is practically correct.
The frustrating for me is that one cannot go back further than year 1583,
I am using the system for archaeological studies and this way cannot get reliable results.
I personally don’t expect that Autodesk will invest very much in the development of this particular tool in the near future, but who knows? Are here someones who tested the Daylight in 2010? 

ivan