Pentax smc DA 18-250mm f/3.5-6.3 Operating Guide (en)

Make sure the filter size matches the lens, then screw the filter onto the front of the lens.
• The compatible filter size for all the lenses are listed on pages 23-24. 
Precaution on filters
• Since the filter becomes a part of the optics when attached on the lens, handle it in the
same way you handle the lens with care to dust, dirt and scratches. Normally, attaching
two or more filters on a lens is not recommended. However, attaching a circular polarizing
filter and another filter would not be a problem.
• Use a circular polarizing filter with Autofocus camera for proper exposure and 
 06-2006 DA_Body_E  05.4.27 15:51  Page 19