Filters or Photoshop??

[Sir Plug]

As I begin to build my kit, I'm looking at the various filters available.

Are they necessary?? Or can you replicate a filter in Photoshop.

In particular, I've been looking at landscapes where a filter is used to bring the sky into equal exposure with the land. Are filters needed for this or can this be done in other ways?

Also, I read about a guy who used a piece of black card, that was flashed in front of his lens during long exposures to give ta similar effect to a ND filter, is this possible using other methods?

Sorry for all the questions but I'm still feeling my way through this minefield!?!?:o

[gjl711]

Most you can replicate especially the colored filters. Even a GND can be replicated but there are advantages to having one in you kit as sometimes ya just need to tone down a specific area while not others. The two I see as not reproducible are a polarizer and ND filters. There is no way in phoyoshop to extend the exposure time of a picture once taken.

[tvphotog]

nik makes polarizing plugins, but they're not nearly as good as using a polarizing filter in the field. Only good if your image of the sea, for example, is filled with glary reflection...when I used it, the plugin improved the image, but flattened the light overall considerably.

I recently bought a circular polarizing filter for the above reason.

[SkipD]

No software can possibly replicate the ability of a polarizing filter to see through a glare on water or glass surfaces.

With a polarizing filter (or your polarizing sunglasses), you can see what is beyond the glare on the surface - the fish swimming below the glare on the water's surface, the store display behind the glare on the window, etc. No software can "guess" at what was beyond the glare and reproduce it.

[Grentz]

A polarizing filter is the main one that cannot be replicated.

As said, ND and Grads are hard to replicate as well.

The rest of the stuff is mostly pointless (colors, warming, etc.) now with digital.

[Blue S2]

A GND filter used with a warming polarizer can give awesome results. Its a hard combo to replicate later. You might be able to simulate the GND with multiple exposures...but not always with it looking natural. Depends on the situation.

[gjl711]

A GND is actually quite recreatable and only one frame is needed. I've never seen a decent looking polarizer though.

[Blue S2]

Adobe's newest Raw Converter has a simulated GND tool as well. And a brush for the same task. You can drag a gradient or paint over a surface and then adjust that that data separate from the rest of the file. Works decently well if the file actually has the data in there.

If you really blew out the sky, you may not be able to fix that. With a real filter, you can not only make it great in the field, but the you have so much more room to work with in PS later.

[rklepper]

Even filters that can be replicated in Photoshop may be desirable. It depends on whether you are interested in the process of photography, or the product. Personally I have more fun with the process. And you would never catch me changing peoples eye color in Photoshop, just because I can. TIFWIW.

[alduin]

A GND is actually quite recreatable and only one frame is needed. I've never seen a decent looking polarizer though.

If you just want to make things darker and don't have a wide gap between the lighter and darker parts of the frame, sure.

For things like water, though, the results may not be reproducible. If you need a slow shutter speed to smooth out some water, you may need the filter in place at the time of exposure to prevent the scene from blowing out.

[gjl711]

...For things like water, though, the results may not be reproducible. If you need a slow shutter speed to smooth out some water, you may need the filter in place at the time of exposure to prevent the scene from blowing out.That would be more like a ND filter, and yes, there is no way one can create a six or ten stop ND effect in PS unless your willing to digitally paint the scene by hand, :)

[Grentz]

Even filters that can be replicated in Photoshop may be desirable. It depends on whether you are interested in the process of photography, or the product. Personally I have more fun with the process. And you would never catch me changing peoples eye color in Photoshop, just because I can. TIFWIW.

Very true ;)