Ealing Studios Ealing Studios ( sometimes called Ealing Film Studios ) is a famed British film company and facilities provider located in the London borough of the same name . Studios have existed on the site since 1896 , making it officially the oldest studio lot in the world . However , the Ealing legacy on the site dates back only to 1929 , and it has only been called " Ealing " since 1931 . As a recording studio . During the run of the original series , video cameras were banned at Ealing . This in general limited its use on the mostly videotaped " Doctor Who " . It was principally used for filming special inserts that were included in scenes that were otherwise videotaped . However , there were occasions in which the main cast would film the bulk of episodes at Ealing . Use in special effects and insert shots . While far more important to the British film industry in general than to " Doctor Who " , it nevertheless played a significant role in recording filmed inserts that were mixed live and / or edited into the principally videotaped " Doctor Who " episodes . In the very early days of the programme , editing as we understand it today wasn ' t practicable . Ealing was thus used to find ways to get around the need to edit . For instance , if a scene required one character to talk to another over a video monitor , the part on the monitor would be filmed at Ealing , then played into a monitor that was on set during the video recording . This allowed for a " special effect " to be achieved without editing the videotape . Moreover , most model work and special effects were filmed at Ealing . Almost every William Hartnell and Patrick Troughton story availed themselves of Ealing ' s facilities for second unit or special photography . Indeed , it was still quite heavily used in this way up until " The Five Doctors " . Its usage for special effects in " Doctor Who " may have diminished in an effort to record more special effects on video so that they matched visually with the videotaped scenes into which they were spliced . Moreover , after the Davison era , model shots were comparatively scarcer than they had been in the past , while at the same time the BBC ' s ability to achieve effects in - house increased . Ealing wasn ' t used again by " Doctor Who " until the filming of the Tenth Doctor two - part adventure " The Impossible Planet " / " The Satan Pit " . As in the past , Ealing was used for special effects recording only , being a suitable location for the filming of the practical effect of fire . Use in principal photography . On occasion , principal photography at the usual studios wasn ' t possible . In such cases , some portions of " Doctor Who " first unit photography occurred on film at Ealing and some happened at BBC Television Centre , Riverside or Lime Grove . A good example of a serial filmed at multiple studios is " The Space Pirates " , in which the main cast filmed at least one whole episode at Ealing , Lime Grove and Television Centre . Ealing was less used for principal photography in the colour era — perhaps because of the more prohibitive costs of colour film stock — but it was nevertheless where the Third Doctor ' s climactic battle with the Nestene Consciousness was filmed in " Spearhead from Space " , and where Leela ' s eyes turned from blue to brown in " Horror of Fang Rock " . Use by single members of the main cast for principal photography . Because of the gruelling , almost year - round production schedule of monochromatic " Doctor Who " , breaks had to be occasionally given to cast members in the middle of recording stories . This was usually accomplished by a trip to Ealing . A cast member would go to Ealing , record a few lines of dialogue and then this scene would be dropped into the episode that they had actually not been present to record . For example , Ealing was used to pre - film sequences involving Carole Ann Ford in " The Aztecs " , William Russell in " The Reign of Terror " and Patrick Troughton in " The Web of Fear " . Thus , Ealing didn ' t just allow the production staff to find a way around logistical problems , it also enabled the cast to go on holiday . As an exterior location . The studio ' s exteriors have been seen in the program as well , notably as the backdrop to Ian and Barbara ' s return to London in " The Chase " and as the backdrop to a WOTAN battle in " The War Machines " . As documentary subject . For the documentary , " A Darker Side " , producer Philip Hinchcliffe and designer Roger Murray - Leach returned to Ealing for a discussion of difficulties of integrating film and videotape into the production of a " Doctor Who " story . ( BBC DVD : " Planet of Evil " )