Yup, its not just weight, its moment of inertia. I once had an off brand 300mm lens which I often shot hand held with a x2 tele-converter The optics were a very simple design and the lens was long. I got some excellent results. Then after that lens got run over by a bus, I switched to a 500mm mirror lens, which was both physically and optically shorter, though heavier. My results with that were much more prone to camera shake. All the best Larry Cuffe >Marc > > >msmall@xxxxxxxxxxxx >Cha robh bàs fir gun ghràs fir! > >--- >Rollei List > >- Post to rollei_list@xxxxxxxxxxxxx > >- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' >in the subject field OR by logging into www.freelists.org > >- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with >'unsubscribe' in the subject field OR by logging into www.freelists.org > >- Online, searchable archives are available at >//www.freelists.org/archives/rollei_list > > > --- Rollei List - Post to rollei_list@xxxxxxxxxxxxx - Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' in the subject field OR by logging into www.freelists.org - Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field OR by logging into www.freelists.org - Online, searchable archives are available at //www.freelists.org/archives/rollei_list