   start: =>
     console.log 'start'
 
-  setBand: (band) =>
+  setBand: =>
+    band = @opts.band
     if band is 'gri'
       @wfits.drawColor('i', 'r', 'g')
     else

      @wfits.setImage(band)
      @wfits.setStretch(@stretch)
  
  updateAlpha: (value) =>
    @wfits.setAlpha(value)
    
  updateQ: (value) =>
    @wfits.setQ(value)
    
  updateScale: (band, value) =>
    scales = @collection.getColorScales()
    index = if band is 'i' then 0 else if band is 'g' then 1 else 2
    scales[index] = value
    @wfits.setScales.apply(@wfits, scales)
  
  updateStretch: (value) =>
    @stretch = value
    @wfits.setStretch(value)

  getExtent: (value) ->
    return (@max - @min) * value / 1000

  updateExtent: (min, max) =>
    min = @getExtent(min)
    max = @getExtent(max)
    @wfits.setExtent(min, max)



  events:
    'next' : 'nextPage getNextSubject'
    'prev' : 'prevPage getNextSubject'
    'setting:alpha' : 'updateAlpha'
    'setting:q' : 'updateQ'
    'setting:scale' : 'updateScale'
    'setting:extent' : 'updateExtent'
  
  constructor: (selector) ->
    _.extend @, Ubret.Sequential
