Flicker API issues, set_id

Can somebody suggest me , why set_id doesn't work properly for Flicker API object call.

IN slideshow it works very well, it selects just images from this set

http://www.flickr.com/slideShow/index.gne?group_id=&user_id=26339121@N07&set_id=72157623827367793&tags=Cars,Lotus,Exige 

but when I tru to use this one :

http://api.flickr.com/services/rest/?format=json&a开发者_StackOverflowmp;method='+
                'flickr.photos.search&api_key=' + apiKey + '&user_id=' + userId + '&set_id=72157623827367793&per_page=' + perPage + '&jsoncallback=?'

It select all images, seams it doesn't work at all !

Thanks!!

per the api documentation, it is not a valid field for that method

if you use the getList method of a set, you can specify a user.