With all Kennel Club Shows, regardless of status, there is a rule about photography, which can differ slightly from show to show, so it's worth ringing the secretary of the show you're looking to go to to check that it is OK to take photographs. Usually you cannot take pictures of a particular dog in the ring without prior permission from the owner/handler
Below is the usual wording that you find about photography at shows -
PHOTOGRAPHY AND VIDEO RIGHTS — The Organisers would like to bring the regulation on photography and filming to the attention of exhibitors, trade stands, press and visitors. It is a condition of all those attending the event that no filming or other form of recording may be taken or made at the venue without express written permission of the Organisers. The taking of photographs in the show venue for sale or reward is strictly prohibited except with the written permission of the Organisers.
Press accredited photographers are provided with permission to take photographs ONLY for use in newspapers, magazines and internet sites – this is for news purposes only. There is no objection to the general public taking photographs of general views of the Show, provided that these are for private use. Specific dogs may be photographed only with the approval of the exhibitor.
No photography or filming is permitted in breed judging rings whilst judging is actually taking place. However, judges may allow it to happen at the end of classes or after the Challenge Certificate is awarded. Filming and flash photography is allowed from outside the ring at all times unless the operation of the camera is actually affecting exhibits. However, if a powerful flash unit is used or it is clear that exhibits are being affected, a ring steward or the judge is empowered to stop the person concerned.
This was taken from one of the championship show schedules
HTH