Plus what about the aperture, will it be variable or fix aperture, with that type of range, I doubt it is any easier to have a fix aperture, so if it is variable aperture, again you would look at how wide it can go... and so on and so for.
So... to make such a lens is not really worth the effort and that is one reason, why up till now, no one had attempt to do it.
Sry, I didn't state clearly. But yeah, 3 lenses cover 10-250mm are good enough to cover lots of different shooting environments.
You want to travel light... the 24-70 + 70-200/2.8 is already about 3kgs in weight. Makes no sense.
You should just get the 18-200 or the tamron 18-270. One lens settle all.
You can cover this range with just 2 lenses instead 3.Originally Posted by HazeMaze
Sigma 18-250 and your 10-22
Last edited by coolthought; 6th December 2011 at 07:45 AM.
we usually use f-stop or stops as a quantitative number to know how much light is reaching the sensor.
f-stop is the expression of focal length over aperture size.
Can I say that adding an extension tube is much like increasing the focal length and hence a larger f-stop number? Therefore, simply put it, adding extension tube decrease the amount of light reaching the sensor?