We have had our room recently plastered and we are now trying to emulsion the walls. However which ever roller we appear to use we seem to be getting a stipple effect. Can you please advise which roller we need to use to get a smooth finish?
Try a 1/4 or 3/8 roller cover. If this isn't smooth enough then you will have to use a sponge roller.
Make sure to prime the new plaster walls really well. This coat, the foundation for the paint, often can be lightly sanded to a very smooth surface. This will help. Also, you can try thinning your emulsion (paint) a little to help it flow out better on the surface.