I am looking to explore shaded vs unshaded annual daylight conditions, as well as look at how the blind schedule relates to direct sunlight exposure.  Is it possible to get the grid data for the direct sunlight exposure (used for ASE calculations) and the unshaded illuminance values from an annual daylight simulation run?  I can get the shaded illuminance from the Ill_8760 output of the grid component, but I do not see any corresponding output for the unshaded illuminance.  Likewise, I do not see an output for the direct sunlight values that go into the ASE calculation.

I have been running my simulations twice: once with and once without operable window shades.  However, the grid viewer lets me preview a point-in-time illuminance (scrub hourly data) "for unshaded condition", so the simulations with shading already include data for the unshaded case; I just do not know how to access this easily for the full annual data set (rather than just a point in time).

As an aside, would I be correct in saying the annual daylight simulation "quality" has little or no impact on the ASE results?

Tags: ASE, Grasshopper, unshaded illuminance

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Hmm, unfortunately I think you're right -- there's no way to get at the unshaded and direct values at present.

The ASE calculation is based on an -ab 0 Daysim run and is unaffected by the quality settings (as you suggest).

The schedules, incidentally, are based on a separate calculation -- an -ab 0 Radiance raytrace along solar vectors, which is both faster and more accurate than the Daysim calc (and ought to replace it at some point).  You can actually change the threshold for the shading schedule calc (50 W/m2) on the Annual Daylight component if you like. 

As an aside, if you want to generate these schedules quickly, you can hide all the outputs on the Annual Daylight component. Likewise you can hide everything but ASE if you want to skip only the indirect Daysim calculation ... but unfortunately this seems to prevent the Ill_8760 output from populating.


Thanks, Jon.  Any chance that data can be exposed in a future release?

Alternatively, is the DLT file format public so that we can parse/extract data from it ourselves?  If I set the daylighting component to export ILL files, I see a name_direct.ill file that I assume is the direct sunlight component (without shades) that is used for the ASE calculations, but no unshaded illumination file from which to draw that data from.

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