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aladyforty Oct 16, 2004 8:39 AM

Today I splashed out and got a polarizer filter for the 300D. Now what I'd like to know is

1. when and for what kind of shots should I use this? Should I use it for all outside shots?

2. Was this a useful purchase given that I have Photoshop and so much can be done with editing programmes

3 What benefits will the filter give me?

sorry to sound really dumb here but I never used one with digital camera before and Im wondering if this was anecessity.

KueH Oct 16, 2004 10:07 AM

This should explain most any question about polarizer use.

1. It can be used inside as well to remove unwanted reflections or glare.

2. Yes, imagine trying to remove the light relections off individual leaves.

3. Read the article as to benefits and limitations. It's easier to understand with examples.

4. Not dumb at all. We've all had questions that needed to be answered. A polarizer is not a necessity, but it is nice to have.

JimC Oct 16, 2004 10:28 AM

Make sure to keep an eye on your shutter speeds with a polarizer attached. For any given lighting condition, ISO speedand aperture, you may need shutter speeds up to 4 times as long for proper exposure (Tiffen quotes a 2 stop loss with their Polarizers).

So, in lower light and/or longer focal lengths, you want to watch out for potential problems with motion blur (or noise if you or thecameraneed to increase ISO speed too much to get shutter speeds faster).

With the Digital Rebel, it's not as much of a problem (because higher ISO speeds are cleaner than a consumer camera). But, with consumer cameras, photos can get pretty noisy, pretty fast as ISO speeds are increased. I saw someone recently with this problem shooting with one of the "ultra zoom" models. His photos were very grainy, and he was getting some motion blur (even in daylight) at longer focal lengths.

Well, the grain was being caused by noise (because the camera's auto iso was boosting ISO speed to ISO 200), and the motion blur was being caused by shutter speeds that were still too slow at longer focal lengths, even at ISO 200 with his model.

The problem turned out to be that he was using aPolarizer, whichwas causing too much loss of light. So, after he started shooting without it, problems solved.

aladyforty Oct 16, 2004 10:59 PM

Thanks, will it be a problem with the rebel set on the auto settings?????? I have noticed slightly more noise but nothing serious.

JimC Oct 17, 2004 2:19 PM

I think the Rebel goes to ISO 400 in Auto (which shouldn't be too bad).

It should not raise the ISO speed unless it needs to. So, in good light (where you'd most likely be using a Polarizer in anyway to help with glare), you probably won't have any problem with it.

aladyforty Oct 17, 2004 8:18 PM


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