En iOS 8 tengo problemas para capturar imágenes de la cámara hasta ahora estoy usando este código para

UIImagePickerController *controller=[[UIImagePickerController alloc] init];
controller.videoQuality=UIImagePickerControllerQualityTypeMedium;
controller.delegate=(id)self;
controller.sourceType=UIImagePickerControllerSourceTypeCamera;
[self presentViewController:controller animated:YES completion:nil];

Pero en iOS 8 obtengo esto:

Snapshotting a view that has not been rendered results in an empty snapshot. Ensure your view has been rendered at least once before snapshotting or snapshot after screen updates.

He intentado con la solución proporcionada porEsta publicación con

@property (strong,nonatomic)UIImagePickerController *controller;

_controller=[[UIImagePickerController alloc] init];
_controller.videoQuality=UIImagePickerControllerQualityTypeMedium;
_controller.delegate=(id)self;
_controller.source,Type=UIImagePickerControllerSourceTypeCamera;
_[self presentViewController:controller animated:YES completion:nil];

y esto

...
controller.modalPresentationStyle=UIModalPresentationFullScreen;
or
controller.modalPresentationStyle=UIModalPresentationCurrentContext;
...

y esto

double delayInSeconds = 0.1;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, delayInSeconds * NSEC_PER_SEC);
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
    [self presentViewController:controller animated:YES completion:nil];
});

y esto

[self presentViewController:controller animated:YES completion:NULL];

y esto

[self presentViewController:controller animated:YES completion:^{

}];

¿alguna idea?