Methodology of my research.

To record my data, I needed to film the subjects to have a record of the movements. I recorded my data using a camera, steading my arms by using a platform to rest my forearms upon. By striding the camera it ensure tat the angle wouldn't change during the recording as this would effect my data results. As my recording was needed to be completed on water this increased the difficulty in terms of accuracy and steadying of the camera angle as the boat was continually moving across the water, however this was minimised by being able to steady my camera angle. This help reduce the parallax and perspective error that could have occurred during the filming as it ensured that the angle and distance of the object stayed the same throughout the whole video. My athletes movements needed to stay parallel to the camera throughout the movement. If I didn't take into account the parallax and perspective error then it would be likely that my measurements wouldn't be correct and give a correct representation of the athletes performance which would have a negative effect if I needed to feedback on their performance from the data collected. 

Parallax error is the shape/size of an objects movement across a camera or a field of view changes. Perspective error is when objects seem to get bigger/smaller as they move to/from a view of a camera. 

During the recording I also used scaling to ensure that my measurements correspond correctly. Scaling a measurement in the field of view and within the plane of interest and this plane should be in the same plane as the movement being used in the study. Using scaling allows the calculation of a relative scale for all future measurements from that precise camera location, making all the measurements correct as the scale will keep everything equal. To ensure that my scaling is correct I will ensure that the movements being recored  take place in the same plane that the scaling was placed. For my recording as it was on water I used the board as my horizontal plane, this measurement equalled 93cm, the sail was used as the vertical scaling which measured 519cm. 

To help with the measurements of the athlete I placed joint markers on my athlete on the femoral Epicondyle, Greater Trochanter,elbow, Acromion Process and trunk. These markers are used to ease the location of the individuals joints during the recording and analysation. The markers should stand out against the background to ease the location finding of the joints under surveillance. However as the recording was taken place on the water his caused some of the markers to wash off, this caused me a disadvantage when analysing my results as it was more difficult for me to locate the specific movements of the joints are they were not clearly marked with the specific markers.