EF IS lenses - why are canon's best not IS?

[filmguy123]

Not sure the mechanics of this, but wondering why most of Canon's best lenses do not have IS (ie many of the lower end standard focal lengths have IS built in, but the L series 25, 50, 85, etc. lack IS. Why do the "worse" versions have it?). It seems only the long focal length high-end L lenses have IS?

All in all, there seems to be a limited set of options for IS EF glass...

I picked up a Milvus lens set for EVA1 and was looking at getting 1-2 IS lenses for when I really need to move quick and need IS to smooth out shakes, plus to have a couple of AF lenses on hand for use with a stills body or a Canon body rental for their AF.

[ggrantly]

To start with, shorter focal lengths have less need for stabilization. Slower lenses need it more; slower lens = slower shutter or increased iso. So the slower lenses are more likely to have it such as the medium zooms and telephotos. Having said that, IS is creeping into all the L glass a bit at a time as second and third generation versions come to market.

[J.Brown]

IS will creep into L series lense more and more. The new 85L with IS is one example.

[deltoidjohn]

These lenses are designed for photography, where IS requirements are very different. In photography IS is more concerned with reducing motion blur - and another way they do this is by using faster shutter speeds. A faster lens allows the use of faster shutter speeds, so the IS becomes less necessary with an f/1.2 or f/1.4 lens.

There is also the issue that faster lenses contain larger glass elements. These larger, heavier glass elements require a much larger, much more powerful IS system than what an F/4 zoom does. So it becomes prohibitively expensive to include IS on very fast lenses.

Keep in mind that proper cinema lenses do not actually use IS. At the higher level, operators usually control unwanted camera shake with weight and ergonomic camera rigs. Use of IS in many situations can cause the image to drift or jump - these movements are usually much more obvious & troublesome than the organic movement from a well-balanced handheld/shoulder rig.

[filmguy123]

This all makes a lot of sense - thank you!