Ok, soooo, what is the image quality like on these lenses? for eg, if I use say my 70-210mm f4 at the 210mm focal length, combined with a 2 x teleconverter, that would make it approximately a 400mm focal length, and then on the *ist D, it would be 1.5 times that - which would be a grand total of 600mm!! Wow, I could get a job as paparazzi with a setup like that.... Not really my thing, but hey, you know Prince Harry is currently staying at a cattle station only a couple of hours from here, could be worth big bucks! hehe. *winks*.... Of course, not much point without the *ist D though... lol....
tan. ----- Original Message ----- From: "Butch Black" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, December 04, 2003 1:41 AM Subject: Re: *ist D - with no lens?!? Hi Tan; I subscribe via the digest, so if this has been answered already sorry for the redundancy. The multiplier factor applies only to the focal length, not the aperture. The area that the sensor takes up is about ½ the size of a 35mm film frame, hence the multiplier factor. Aperture is a function of the size of the opening in relation to the actual focal length of the lens. For instance, the physical size of the aperture opening on a 200mm lens at f4 will be larger then f4 on a 50mm lens, but both will let the same amount of light in. Where the multiplier factor does not change the lens itself, it only designates a "cropping factor" compared to 35mm, therefore, no change in aperture. Butch Each man had only one genuine vocation - to find the way to himself. Hermann Hesse (Demian)
