query: SELECT ?item ?range_nm_per_focalheight_m ?nm ?mfocal 
  {
      ?item wdt:P31 wd:Q39715 ; wdt:P2923 ?rawfocal ; wdt:P2929 ?rawrange .
    
      ?item p:P2923 ?pfocal .
      ?pfocal psn:P2923 [ wikibase:quantityAmount ?sifocal ; wikibase:quantityUnit ?sifocalunit ]  .
      ?pfocal psv:P2923 [ wikibase:quantityAmount ?rawfocal ; wikibase:quantityUnit ?rawfocalunit ] . 
      wd:Q11573 p:P2370/psv:P2370 [ wikibase:quantityAmount ?convfocalqt ; wikibase:quantityUnit ?sifocalunit ]  
      BIND(?sifocal / ?convfocalqt as ?mfocal ) .  
    
      ?item p:P2929 ?p .
      ?p psv:P2929 [ wikibase:quantityAmount ?rawrange ; wikibase:quantityUnit wd:Q93318 ] . 
      BIND(?rawrange as ?nm ) .
      
      BIND(ROUND(?nm / ?mfocal*10)/10 as ?range_nm_per_focalheight_m )
  
  	FILTER (?item not in ( wd:Q15397819 , wd:Q4999731)  )
  }  
  ORDER BY DESC(?range_nm_per_focalheight_m)
  LIMIT 50