APSF
// Find the extended magnitude of DSOs and their detectability in the current telescope.
// Add the info to user-defined columns.
// Based on http://www.starastronomy.org/Library/collett.html
// Paul Rodman, Nov 2006.

function log10(x as double) as double
  return log(x)/log(10.0)
end function

dim MagE,size,MagV,limit as double, i,id as integer, usercols(-1),sm,sd as string

dim UseApparentMag as boolean, MagVColumn, DetectColumn as integer

usercols.Append "No"
usercols.Append "User 1"
usercols.Append "User 2"
usercols.Append "User 3"
usercols.Append "User 4"

MagVColumn=RestoreIntegerValue("MagVColumn",1)
DetectColumn=RestoreIntegerValue("DetectColumn",2)
UseApparentMag=RestoreBooleanValue("UseApparentMag",false)

if CurrentTelescope=nil then
  limit=0.0
  SetCaptionParameter("No Telescope Specified",1,true)
  id=0
else
  limit = CurrentTelescope.MagnitudeLimit
  SetCaptionParameter("Telescope Magnitude Limit: "+format(limit,"-0.0")+".0:0",1,true)
  id=DetectColumn
end if

SetPopupParameter("Extended Mag (Ext.Mag)",MagVColumn,usercols)
if id>0 then SetPopupParameter("Telescope Detectability (Detect)",id,usercols)
SetBooleanParameter("Use Apparent Magnitude",UseApparentMag)

if not EditParameters then return

MagVColumn=GetPopupParameter("Extended Mag (Ext.Mag)")
if id>0 then DetectColumn=GetPopupParameter("Telescope Detectability (Detect)") else DetectColumn=0
UseApparentMag=GetBooleanParameter("Use Apparent Magnitude")

for i=1 to nObjects
  if UseApparentMag then MagV=Obj(i).ApparentMagnitude else MagV=Obj(i).Magnitude
  if MagV>0.0 and MagV<30.0 and Obj(i).Size1>0.0 then
    size = sqrt(Obj(i).Size1*Obj(i).Size2)
    MagE = MagV + 5.0*(log10(size*60.0)-log10(70.0))
    sm=format(MagE,"-0.0")
      
    if limit=0.0 then
      sd = ""
    elseif MagE/limit<0.9 then
      sd = "Yes"
    elseif MagE/limit>1.1 then
      sd = "No"
    else
      sd = "?"
    end if
  else
    sm = ""
    sd = ""
  end if
  select case MagVColumn
    case 1
      Obj(i).User1 = sm
    case 2
      Obj(i).User2 = sm
    case 3
      Obj(i).User3 = sm
    case 4
      Obj(i).User4 = sm
  end select
  select case DetectColumn
    case 1
      Obj(i).User1 = sd
    case 2
      Obj(i).User2 = sd
    case 3
      Obj(i).User3 = sd
    case 4
      Obj(i).User4 = sd
  end select
next

if MagVColumn>0 then UserHeading(MagVColumn)="Ext.Mag"
if DetectColumn>0 then UserHeading(DetectColumn)="Detect"

SaveIntegerValue("MagVColumn",MagVColumn)
SaveIntegerValue("DetectColumn",DetectColumn)
SaveBooleanValue("UseApparentMag",UseApparentMag)