Please explain IS modes to me

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Howdy all!

I will risk being a "dummy" and ask a question.

I keep reading about Canon IS lens with 2 modes and 1 modes or IS capabilities in both directions, or something about working during panning but not other times. As you can tell I am confused. What I would like to see is a explanation of features IS lens, not how they work optically or the techinical workings. Maybe I am looking for a brief tutorial about IS lens, I am suprised Philp/Bob have not put one up on photo.net. One more question, my wife hates ( I have tried to convert her) using tripods, would an IS lens be advantageous for her?

We already are Canon folks, so that is not an issue. The type of photographer she likes is hand-held shots of people at "street fairs," little pieces of nature(not macro but not scenics), some animals (whatever we run across hiking), and we have little nieces and nephews. Hope I have been clear with my questions.

Thanks for the help--- BV

-- Brian Vega (vega@micron.net), January 06, 1999

Answers

The dual mode IS lenses (300 f4 L and 100-400 L) have a switch that turns off the sensor that detects side to side movement. This is for panning, but I have not had any problems panning with my 75-300 IS. There have been reports of jerky viewfinder images with it, but I have not experienced them.

I don't look at IS as being a substitute for a tripod, just as an alternative when a tripod isn't ideal or useful at all. It is better than handholding and equivalent lens, but probably not as good as using a heavy tripod. Used within its limits IS works very well. You still have to use good technique, but if it is already good you will be able to use a shutter speed at least 2 stops slower than you would normally attempt.

-- Brad (reloader@webtv.net), January 06, 1999.


On a dual mode setting the lens will detect and cancel out any movements. Turning of the sensors will allow you to pan and create a blurred background. Is that an accurate summary? Also is the 75-300 a dual mode lens.

As to subsituting for a tripod, I am aware of that, but my wife likes to shot hand-held. My question is will an IS lens allow her to get shots that would not be possible with a regular lens? Low light situations?

Thanks--- BV

-- Brian Vega (vega@micron.net), January 07, 1999.


Brian,

There are two sets of sensors. The 75-300 is not dual mode. It is either on or off. The dual mode lenses let you turn off the horizontal movement sensors or all of the sensors. As I said, I have not found the lack of a dual mode setting to be a handicap with my 75-300, and I keep IS turned on any time I am handholding.

As for low light photography, a 50mm f1.8 would work about as well, but you wouldn't have the 300mm end of course. Some people would say that it would work better since you get a 2 1/3 stop light gain with it, and can shoot in lower light before you get into the 1/60 second range. I depends on how you look at it. If you can shoot at 1/60 @ f5.6, the 75-300 will work. Light does not have to be very dim for shutter speeds to get slower, which I don't recommend at the 300mm end unless you just have to do it. If you need a 300mm handholdable lens, IS will outperform everything else. If you just need a low light lens, the 50 f1.4 or 50 f1.8 or other fast lens would be better.

-- Brad (reloader@webtv.net), January 07, 1999.


Brad,

Thank you for the (clear) explanation.

-- Brian Vega (vega@micron.net), January 07, 1999.


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