Part 107 UAS crew reported momentary lost of visual contact with the UAS during the flight.

Narrative

The pilot was operating a small UAS over private property to survey timber damage. The damage was approximately 100 feet wide by 1 mile long. To maintain sight of the aircraft; the RPIC conducted two flights. One in the estimated middle of the strip; and one at the end. During the course of one of the photography gathering flights; the small UAS was approximately 2500' away from the RPIC and 200' AGL. The aircraft become obscured by the sun and visual contact was lost. There were two visual observers also watching for the aircraft while the RPIC was taking pictures with the camera. Visual contact was momentarily lost and the RPIC referenced the transmitter to identify the aircraft's position. When visual contact could not be regained; the aircraft was flown toward the takeoff point until it could be seen again. The aircraft never went over 200-250' AGL. Due to the proximity of a small uncontrolled airport (1nm to N); the operating ceiling was capped at 250' as a precaution. The flight was conducted in class G airspace with no need for an airspace authorization. Upon reflection; the flight should have been broken up into smaller sections so that visual contact could be maintained throughout the entire flight.The RPIC considers the environment to be a cause for the pushing of visual limits. There was a time pressure to finish the flight within the flight time of two batteries. Also; at the far south end of the flight area there were mosquitoes causing a major distraction.