Splendid performance by Oslo Philharmonic

Proms: BBC SO; OSLO PHILHARMONIC Royal Albert Hall, London

Modesty is becoming, but Judith Weir's modesty is beginning to seem like tameness. At least, in Friday's Prom, her commission, Moon and Star, sounded like its title. Setting a poem by Emily Dickinson ("Ah, Moon - and Star!/You are very far -") the orchestra was coloured by a lot of high woodwind and tinkling percussion. The BBC Singers were treated as a contributory strand, moving slowly except in a section that was syncopated and staccato, disappointingly like Aaron Copland, though most of the music, with its colourful harmonies in parallel motion, was more reminiscent of Debussy's Le Martyre de Saint Sebastien, without its erotic force, or Messiaen, without his musical boldness or religious conviction. Weir said that when she looked for poems about the universe, she rejected ones that carried "religious baggage", though surely Emily Dickinson was mystical in some sense.

The beginnings of musical paragraphs were more striking than their continuation, and at around 15 minutes the piece seemed long for its content. Nor, for all Weir's caution in word-setting, which offered none of the challenges in agility or intonation that the BBC Singers are used to, was the text audible in the hall.

Moon and Star made an ear-tickling interlude between Webern's Passacaglia and Mahler's Das Lied von der Erde, in which Jeffrey Lawton replaced the indisposed tenor soloist, Siegfried Jerusalem. In Mahler's opening and fifth movements, Lawton was credible as a swaggering drunkard, and his top notes rang out bravely, but his heaving vibrato was not always purely at the service of poetic expression. In the even-numbered movements, the ubiquitous mezzo-soprano Anne Sofie von Otter was correct and rather dull: she was swamped in the noisier passages of "Von der Schonheit", and her voice was too lightweight to be ideal in the sumptuous farewell of the final movement. The star was really the BBC Symphony Orchestra under Andrew Davis - or Mahler himself, for giving them such lean and telling lines.

On Saturday, the splendid Oslo Philharmonic Orchestra brought over a sort of updated version of the Vaughan Williams Tallis Fantasia in the form of Magnar Am's Study on a Norwegian Hymn, though form didn't seem its strong point. It was merely a token home-grown appetiser before the main courses, which were certainly satisfying. Mariss Jansons conducted a ripe performance of Strauss's Also sprach Zarathustra, in which an electronic organ replaced the Albert Hall's own instrument because of the orchestra's slightly higher pitch; and very effectively balanced it was, too.

Sibelius's Second Symphony brought the house down, quite rightly, for it was magnificently played and highly emotional, though the intensity of the big moments did not eclipse the strong lines of Sibelius's design - that was clear from the fact that people forgot to cough. In the finale, Jansons indulged his gift for histrionic mime, since he knew the orchestra would see to the rest.