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gman1987 Jan 11, 2010 10:41 AM

Thanks guys. This really helps. I'm taking a trip to the mountains this weekend and hopefully will get a chance to practice on some landscapes. I know I will have many more questions as I start using it more.

gman1987 Jan 12, 2010 1:08 PM

Ok Next question.
Someone mentioned not to bother with a uv filter but to look at neutral density or polorized filters. Are there different types? Is one ND or polorized filter as good as the next? If I only had one what would be the one to get? I saw a circular polorized and uv filter kit in Walmart for $20. Would these be decent filters or are good filters expensive as well? Would the uv filter be useful as another means of protecting the lens and can you use the lens hood with a filter? Not sure I need these yet especially if significant $$ is involved. The wife is still getting over the sticker shock from the camera and bag. :D

TCav Jan 12, 2010 1:22 PM

Neutral Density filters are to reduce the amount of light that enters the lens without decreasing the aperture, or when reducing the aperture and/or reducing the exposure time isn't enough. They are available in 1, 2, or 3 stop densities. There are also graduated neutral density filters for when you want to dim the light in one portion of the frame (like the sky) but not another (like the ground.)

Polarizing filters are for reducing glare and will also enhance colors.

If you only went with one filter, I suggest you get a Circular Polarizing Filter. It's more useful in more conventional situations than a neutral density filter.

And don't waste your money on cheap filters. Tiffen would be the minimum filter I'd recomments. Hoya, B+W and Heliopan are better and worth the extra money. A cheap filter can noticeably reduce image quality and induce flare.

For more info, see

JohnG Jan 12, 2010 1:23 PM

OK, first and foremost - be careful whenever someone tells you you NEED a piece of gear without explaining WHY. Having said that, let's talk about the 3 filters you mentioned and what they each do:

UV filter: primary purpopse was to block UV light - no benefit whatsoever with the coated lenses in todays DSLRs. So, what UV filters are used for is to "protect the front lens element". Feel free to do some searches here and elsewhere. Lots of posts on the subject - some say it's good piece of mind, others say it offers no real protection and possibly degrades image quality or produces flare. Do some searches to see the pros/cons. My personal preference is to use lens hoods. I no longer use protective filters - but others do. search here and you'll see the arguments for/against.

Polarizing Filter: First, make sure it's "circular" and not linear. They both do essentially the same thing but in different ways and some DSLRs have issues with linear polarizers. If you own a pair of polarized sunglasses you can see the affect they have. First, they do act as suglasses - they cut down by almost 2 stops the amount of light geting in. Their biggest affect is in two areas: landscape where they can make the sky a deeper blue and provide more contrast with clouds. The CP is actually two pieces of glass one fixes to your lens and the other rotates. Rotating the second one changes the intensity of the affect.

The second benefit is a CP will cut down on reflections - so if you are shooting through glass or shooting cars or the like - the CP will help reduce the reflection you see in those objects.

A ND (Neutral Density) filter - this is like having sunglasses over PART of the image. Its a filter with one side darker than the other. They come in types that have a hard line difference or a graduated difference. And you can buy them in different strengths. They are primarily used for landscape work - imagine you're in a stream bed with trees all around but sky still visible. The sky is MUCH MUCH lighter than the scene down at the stream bed. A ND filter can be used to darken the light from the sky portion of the image. With the HDR technology of today this same affect can be achieved via software. The challenge with ND filters is they have a static affect - i.e. a 1 stop or 2 stop ND. So having just one filter may be good in one instance but not in another.

IMO, NONE of these are NEED TO HAVE items. Between the CP and the ND, the CP affects cannot be achieved as well via software so it's a more useful filter - but certainly a NICE TO HAVE, not a need to have.

Hards80 Jan 12, 2010 1:47 PM

i agree that none of them are a need to have item.

UV - i dont use them, they degrade image quality, i use a hood for protection

CP- I do use these from time to time, the reflection cutting effect can be nice in certain circumstances like water etc. And they can deepen the blue of a sky, but really that can be done in post-process as well.

Neutral Density - a regular Neutral Density is a uniform filter that reduces the amount of light coming in. this is useful because it can allow you to have longer exposures for when you want to smooth water, etc. this is a very nice filter if you do any kind of landscapes with water you want to smooth. a Graduated Neutral Density has a dark upper part and a clear bottom part, this allows you to properly expose a bright sky on dark foreground, this is useful in landscapes, but can be replicated by using HDR, or simply taking 2 exposures (1 of sky, 1 of land) and combining via layers.

so 2 filters cannot be replicated in post-process. certain aspects of a circular polarizer, and a standard neutral density. however, the neutral density is only useful if you want to smooth water with a long exposure on a tripod. and the circular polarizers main effect (dark blue skies) can be replicated in post-process now-days.

so really, none are really needed, but can be nice in CERTAIN instances.

gman1987 Jan 12, 2010 1:55 PM

Thanks, I'll probably forego the the filters for now and just concentrate on learning to shoot with what I have.

griffina6 Jan 12, 2010 1:57 PM


Originally Posted by JohnG (Post 1038630)
OK, first and foremost - be careful whenever someone tells you you NEED a piece of gear without explaining WHY. Having said that, let's talk about the 3 filters you mentioned and what they each do:

Thanks John for the explanations.

As another new photographer I'll share my story...

When I first started buying lenses and right on the same web page was the recommended accessories I figured I had to get a UV filter for every lens I bought. My thoughts was to use it to protect my large investment. So for the first three that is what I did.

However, I have since come to agree that lens hoods are the way to go if your lens has one. Initially at night with the 50mm and 85mm I was getting a weird green spot on some images until I realized it was caused by the UV filter.

For the 70-200mm - I love the lens hood and use it all the time indoors and out. When I store it I do place the UV filter on it but the only time I shoot with it is at motocross tracks to protect the lens from flying rocks and dirt. I have seen motocross pics where a Circular filter was used and I may try that someday.


shoturtle Jan 12, 2010 2:34 PM

If you are going to shoot someplace where sea-spray, sand or dust is most likely, you may want a clear filter, or a haze 1 filter for protection. When out of the those environment I would remove the filters.

Mark1616 Jan 12, 2010 2:39 PM

For example I keep a filter on my main lens for general use but for weddings/studio shoots etc it comes off so I don't lose any quality. That is the only lens I have a filter on as it is my main one for moving around with.

gman1987 Jan 13, 2010 8:42 PM

Can some one explain depth of field to me? I'm reading about the AV mode and it says it is good for depth of field and action shots with the largest aperture. I guess I'm having trouble wrapping my brain around how the same setting do both. It would seem that the TV mode would be good for sports but i know someone here said they would only use AV and manual. If this is to big a subject to tackle maybe a link to a good discussion? Thanks

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