Filters for protection and sealing

[Thorburn]

I've never bothered much with filters in the past other than occasionally using a circular polariser, but as I'm starting to pick up some nicer lenses I was wondering what peoples opinions are on fitting a filter to help seal from the elements and protect it from any damage.

I have a good friend who uses a 5D Mk2 + 24-105mm f/4L, so a similar combination to me, and he said he never bothers with them as he finds they give a little bit of vignetting. On the other hand however I discovered yesterday that my old lens had a few small spots of dust inside the lens and I know that a filter is required for weather sealing.

What's the general consensus? I'd like to keep things in as good a condition as possible as I see this as a camera I'll be keeping for a long time. Looking at fitting a Hoya UV filter if I do put one on it, and another likely on to a 300mm f/4L when I buy one in the future.

 

[Nawty]

This question gets asked about once a week if not more often, in fact another one has just started here:

http://www.talkphotography.co.uk/forums/showthread.php?t=444120

So you may as well piggyback that one

 

[hollis_f]

I know that a filter is required for weather sealing.

There are only a few lenses that require a filter to complete weather sealing. The 24-105 is not one of them. If your lens is old then I doubt it has weather sealing with or without a filter.

 

[HMansfield]

If dust is inside the lens, then it hasn't come in through the front element, and therefore a filter would have done nothing.

 

[Thorburn]

Ah okay. What causes that and how do I prevent it?

 

[seriousrikk]

Ah okay. What causes that and how do I prevent it?

Changing lenses causes it usually, very difficult to prevent. More likely to happen in zoom lenses which change length too, as the zoom mechanism is moving air around - which can draw unwanted particles in.

Fortunately, it also has no effect on image quality, so I don't worry about a bit of dust in the lens now.

 

[hollis_f]

Ah okay. What causes that and how do I prevent it?

Don't buy lenses that move in and out as you zoom/focus. When they move in and out they have to let air in or out (or create a vacuum, and nature tends to abhor that). Of course, that limits your choice quite significantly.

Or you could take Richard's advice and ignore it.

 

[Thorburn]

Thanks for the info.

Won't worry about it too much then.