We need to query the SDSS SQL search to get the g and r data. In order to do this, we have to figure out how to format the right ascension and declination values, which are pretty much the coordinates of the open cluster. According to Wikipedia, M35's coordinates are right ascension 06 hours, 09.1 minutes, declination 24' 21''.
So there are 24 hours in the right ascension coordinate system thing, and 360 degrees in lattitude/longitude. So to calculate from right ascension to longitude, we need to convert 06 hours, 9.1 minutes to entirely hours, and then multiply the result by 15. So we get 93.75 degrees.
The declination should be 24.35 degrees.
Since the M35 cluster is about the size of the full moon, and the angular diameter of the full moon is about 30 arcminutes, we are going to examine a portion of sky with radius of 6 arcminutes. This should encompass the center of the M35 cluster.