[Kirk Keyes]

a specular reflection is of the same intensity as the source, so an incident reading in direct sunlight should be the same as a spot reading of a specular reflection. Jay

Not it you have the light integrating sphere on your meter.

If the dome is still on the incident meter, then you have just attenuated the light striking the light meter sensor.

If you removed the dome, then you have just turned your incident meter into a reflection meter. Some meters allow you to do this - but you need to have special reflectance attachments to get accurate numbers and also to know the field of view.