[DaveHolmes]

Hi, still very new but loving the K-x, hope to get some pics up in the next week or so....

Anyway...

Filters....
UV.. Polorising.. Neautral Denisty.. Warming.. There seam to be loads of different types of filter out there and I confuse easy!!

Do I actually, really need any of these? How important are they? Where do I start?

Please bear in mind I've had the K-X less than a week and am skint for the next 2 months!

[RioRico]

There are many threads on filters here, but I'll give a brief summary anyway.

UV filters are useless, except to the folks selling them to you, overpriced. Skylight filters are useful if you're in a cruddy environment and want to keep mud, blood, beer, sand, paint etc off your lens. For general protection, a lens hood is best.

Polarizers are good if you're dealing with glare, reflections, and blah skies. Neutral density filters are good if you need to S-L-O-W down your shutter. Graduated ND's are good if your target is highly contrasted -- like dark ground and bright sky.

Special colored filters have exotic uses. IR-pass filters are needed for infrared work. I use blue-violet filters to emulate actinic (UV-violet-blue) light seen by early photo emulsions. Old B&W filter sets (yellow, orange, red, green) are useful for effects.

That's the overview. Save your money until you think you REALLY need something.

[Ash]

Hi there Dave, and welcome.
Firstly you don't NEED any filters on any of your lenses.
THe only filters you'd be using for any real purpose on a digital camera/lens combo would be the UV/clear, circular polarising and neutral density filters.

UV/clear filters are useful only for protecting the front element of your lens (might be handy for when you shoot in wet/salty/dirty conditions).

CPLs are good for eliminating glare (look up the effect that has on photos with reflective surfaces in them) and clarifying certain colours.

ND filters are good for permitting long exposures during the daytime, such as for waterfalls.

Hope this helps.

edit: but it seems someone got to it before I did.

[DaveHolmes]

UV/clear filters are useful only for protecting the front element of your lens (might be handy for when you shoot in wet/salty/dirty conditions).

So UV filters are essentially just scratch protectors then?

Cheers for the welcome finding this whole site very useful and it was in fact pivotal in my discision to go with the K-x rather than the Nikon D5000!

[Ira]

So UV filters are essentially just scratch protectors then?

Yep--same with skylight filters. But since you're adding an extra layer of glass, usually CHEAP glass, you're also degrading the quality of your image.

Basically, a CP--Circular Polarizer--is your best bet for a filter that really DOES something. It darkens washed out blue skies, and really ups the contrast of your images. It's a double kind of thingy mount where you spin the filter so it bends the light rays in the direction for best effect. (You can see the difference in the viewfinder as you spin it.) Keep in mind that your effective aperture is reduced with a CP, since the light has to pass through layers of "stuff." So if your F stop says 5.6, you're actually shooting at F8, without the associated increase in depth of field.

Straight neutral density filters don't do anything except reduce the amount of light entering the lens, usually used for scenes like a flowing stream. In other words, you want that water to have a special glow/blur/magic...you want to shoot at your lens's best aperture (F8, for example)...but you really need a 5-second exposure for the glow--even at your slowest ISO. The only way for proper exposure and to reduce the amount of light entering the lens with a 5-second exposure is with an ND.

Graduated NDs are NDs on one part of the glass and fade down to nothing. So you would use the ND part to "underexpose" a sky that's too bright, but keep the ground stuff untouched.

NDs are tricky, and usually come later in your arsenal.

[adwb]

DaveHolmes,
bear in mind that if you use photo shop or similar the filter effect can be applied later.
Buy a polariser as Ira said , I think that is one that should be supplied with every camera sold and any camera sales man worth his salary should suggest one at the point of purchase yet they never do.
Alistair

[mattdm]

DaveHolmes,
bear in mind that if you use photo shop or similar the filter effect can be applied later.

You can't really apply a polarization effect later if you're using it to cut out unwanted reflections.

[adwb]

and thats why I said
"Buy a polariser as Ira said , I think that is one that should be supplied with every camera sold and any camera sales man worth his salary should suggest one at the point of purchase yet they never do."
Alistair

[ChooseAName]

Get a lens hood. It will cut down on the amount of stray light getting into the light, and will help prevent lens flare if you are in a situation where that's a concern. Lens hood >> UV filter, unless you are in a situation where it really could help (i.e. sandstorm or something).

A polarizing filter is the only one I have. Make sure you get a good quality one, don't buy the cheapest one at your local camera store.

[DaveHolmes]

Cheers. I'll get one (polarising) as soon as possible.
Thanks for all the help... Again:-)

[mattdm]

and thats why I said
"Buy a polariser as Ira said , I think that is one that should be supplied with every camera sold and any camera sales man worth his salary should suggest one at the point of purchase yet they never do."
Alistair

Yeah, not arguing, just clarifying.

[Ash]

No worries Dave, but also be aware that there are times where you DON'T want to have the polarising effect on your shots, so you may find yourself having to take the filter on and off according to your conditions.

Times when you would want the polariser: midday landscapes, most seascapes, for other reflective surfaces, etc. Times when you don't want the polariser: low-light or night photography when you want to maximise your shutter speed.

It can be argued that you could turn your CPL filter so that its polarising effect is minimal, but you're still left with a mild neutral density effect from the natural darkening effect of the filter (approximately 1 to 1.5 stops of light).

[tibbitts]

I have a K100 and K200. On the 100, and perhaps somewhat less with the 200, it's very very easy to blow out skies in routine photography. Even when you shoot raw, unless you use a technique such as hdr (which has issues when subject movement is involved), if you use enough exposure to hold shadow detail, you can lose the highlights. For those times, a split ND is very useful.

So, there is really no way to replicate the effects of a plain ND, split ND, or polarizer, with software. Color correction filters, particularly filters such as the slight warming filters that were popular in the film era, generally can be replicated with software.

Paul

[smigol]

I have sworn by not using filters on my lenses and have made the effort to ensure that I use a decent hood.

Recently I've been using some longer, older, non-ED lenses and was curious about what was happening with Purple Fringe.

Since I use these lenses with my telescope setup, I was annoyed by PF as it makes the star images bloat and become less distinct. When I started using a light pollution filter, these star images became much sharper with much reduced PF. This got me to thinking and looking at the frequency curves on the Light Pollution filters vs the UV filters that I had been using in the past.

I did some controlled testing with my non-multicoated Hoya UV filter on a 200mm F2.5 lens. Shooting wide open at branches silohuetted against a hazy sky as well as shooting the sun reflection on chrome, I found that the PF was significantly reduced, even at wide open. There was less difference noticed at lower f numbers, starting at around F5.6 and F8.

I've since picked up a couple of MC Hoya UV filters and have been enjoying the new-found capabilities of my older lenses.

Given that these filters were purchased just for PF control, I don't forsee using them on my shorter primes.

The reason why I selected the Hoya filters is because of the specific curves shown in this test published on the web: UV filters test - Introduction - Lenstip.com

I hope that these responses help.

[Kerrowdown]

Save your money until you think you REALLY need something.

I think that's good advice, you will not have loads of redundant or seldom used filters laying around.