How do I get 0.9X with the new EF70-300 IS USM?

[dRebelXT]

Some websites says this lens can get 0.9X with ET25mm. I tried but the smallest subjects I could fill in my 350D frame is the 77mm lens cover. That would convert into a 77mm/(35/1.6)=0.28.

My experience is that at 70mm it has shortest focus distance, maybe 40cm, then as focal length gets towards 300, focus distance also change proportionally to nearly 1m at 200mm, so unable to achieve extra magnification.



http://www.photo.net/equipment/canon/70-300is/

Quote: Canon EF 70-300/4-5.6IS USM Specifications Focal length 70 - 300 mm Maximum aperture F4.0 - F5.6 Minimum aperture F32 - F45 Angle of view Horizontal: 29° - 6° 50' Vertical: 19° 30' - 4° 35' Diagonal: 34° - 8° 15' Lens construction 15 elements in 10 groups Diaphragm blades 8 Closest focusing distance 105 cm (41.3 in) Maximum magnification 0.26x (at 300 mm) Distance information Yes Image stabilizer 3-stops AF actuator Micro USM Filter diameter 58 mm Dimensions (dia x len) 76.5 x 142.8 mm Weight 630 g (1.4 lb) Magnification with extension tubes • EF 12 II: 0.32x - 0.4x • EF 25 II: 0.39x - 0.9x Lens hood EW-65B Soft case LP1222 Extenders • EF 1.4x II: Not compatible • EF 2.0x II: Not compatible

[CYRN]

have you tried et25mm @ 70mm