1. A system for emitting and detecting electromagnetic radiation of multiple wavelengths to observe particles in a polydisperse solution, the system comprising: a first light source constructed to emit a first beam of electromagnetic radiation at substantially a first wavelength; a second light source constructed to emit a second beam of electromagnetic radiation at substantially a second wavelength; a combining structure that merges the first and second beams into a combined beam, wherein the combined beam is directed at a specimen chamber, the chamber is constructed to allow a portion of the combined beam to scatter perpendicular to the combined beam; the specimen chamber further comprising a calibration mask, the mask including at least two calibration marks; a calibration light source constructed to emit a calibration beam of electromagnetic radiation comprising the first and second wavelengths; the calibration light source directed at the calibration mask parallel to the scattered portion of the combined beam; the scattered portion of the combined beam and the calibration beam directed to a decombining structure that separates the electromagnetic radiation into the first wavelength radiation and the second wavelength radiation; the separated first wavelength radiation is directed to a first sensor biased to detect electromagnetic radiation at substantially the first wave length; the separated second wavelength radiation is detected by a second sensor biased to detect electromagnetic radiation at substantially the second wave length; a processor connected to the first and second sensors, the processor configured to perform the following steps: when the calibration light source is actuated: obtaining a first calibration image from the first sensor and a second calibration image from the second sensor; detecting the calibration marks from the calibration mask in the first calibration image and in the second calibration image; determining a calibration correction based of the location of the calibration marks in the first calibration image and the location of the calibration marks in the second calibration image; when the first and second light source are actuated: obtaining a first detection image from the first sensor and a second detection image from the second sensor; adjusting the detection images relative to each other based on the calibration correction.