Filters required for digital photography?

[Pband]

Hi friends,
I just wonder about whether various filters are anymore needed for digital photography where we can edit and filter the photos (although I am absolutely new about PhotoShop)?
I only have UV filters for my lenses. Do I also require to buy any other filter or my photos can be edited with various filter effects after I shot the photos?
Please help me as I am setting out for a tour for 17 days.

 

[AlexColeman]

Neutral density, and a split/ nd grads. Can't replicate effect, where as polarizer and uv can be duped for the most part. Polarizer/ with reflection is one you cant duplicate.

 

[Josh66]

CPL (circular polarizer), ND (neutral density), & IR (infrared) are the only ones I can think of that can't be done in photoshop.

A CPL will probably be the most useful for you. You can use it to cut down on or eliminate glare in most cases.

 

[Dwig]

CPL (circular polarizer), ND (neutral density), & IR (infrared) are the only ones I can think of that can't be done in photoshop.

A CPL will probably be the most useful for you. You can use it to cut down on or eliminate glare in most cases.

Thats a good list of the commonly used one.

There are a few other extremely narrow band cutoff filters that can't be replicated in post processing. The most commonly used of these would be the very deep red, equivalent of the Wratten #29 (the standard #25 is easy to replicate). The deep cutting special UV filters (these look visibly brownish and are NOT the common useless UV or UV-Haze filters) also can't be replicated in post.

Any of the color correction filters (e.g. Wratten 80, 85, 82, & 81 series) can easily be replicated with simple white balance adjustments.

 

[Pband]

OK. So, I have decided to by CPL for my low budget as I already have a UV filter.
Somebody told me it is not good to put both of the UV and CPL filters to a lens at a time, since they will absorb more light and so I should only put CPL which also works likd UV more or less. Is true? Will only a CPL good enough for me?

 

[Josh66]

I don't know that a CPL actually filters out UV light, but I wouldn't worry about it too much. I think there are very few situations where you would actually need the UV filter (for it's UV filtering capability).

Most people use them as an extra layer of protection between the lens and the the rest of the world. If this is what you're using it for, it would be completely pointless underneath another filter. The filter on top (the more expensive one too, probably) is now your added layer of protection.

The problem with stacking filters is that you can get light bouncing around between them. (Also, that it can cause vignetting.)

One time when you may need to stack filters is if you have 2 ND filters. You can stack those to let even less light through.

 

[Dwig]

...
Somebody told me it is not good to put both of the UV and CPL filters to a lens at a time, since they will absorb more light...

Right recommendation, but for the wrong reason.

Never combine filters if you can avoid it. The main reason is that stacked filters are extremely likely to cause flare problems. Stacking also increases the image quality loss on the edges from astigmatism and real chromatic abberation (not the sensor based CA). It can also lead to vignetting issues.

Secondly, the UV filter does absolutely nothing for the picture. No digital camera and general use film made since the 1960s "sees" any UV. Its primary purpose is to add to the dealer's profit (they are very high markup items) and they may possibly help protet the lens from damage in some odd situations. They do more to protect the filter thread on old metal barrelled lenses than anything, and I've seen cases where the presence of a UV filter caused the lens to be damaged when it wouldn't have been if no filter was present.

 

[Pband]

OK. So I am going to take off the UV filter from my lens taking it as a bad investment.

I more thing I wonder about. I know I am absolutely novice in the field so the question arises in my mind. The question is a follows:

I only have my kit lens 18-55mm with my camera. It has a mount of 58mm. So I bought the filters of 55mm mounts. In near future, when I will go for some other lens for the same body, will the new lens have some different mount and I will have to invest again for the same filters?

 

[Josh66]

58mm is probably the most common size for Canon lenses (not sure if the same is true for everyone else), but as you move up to higher end glass they tend to get bigger.

Most people buy their filters to fit the largest lens they have and use step down rings to mount the filter to the smaller lenses.

 

[TUX424]

For Nikon's lower end lens such as the 18-55, 50 1.8 and 55-200 all have filter sizes of 52mm, It seem the more expensive that the lens become the larger of a filter size they are going to have. I am pretty sure that 77mm is a standard, at least for nikon it is.

If you already have the UV no reason not to you it, other wise it was an even worse investment since you are getting nothing out of it. At least with is on your lens you are getting some kind of protection.