[csa]

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The one you leave at home...

Apart from occasional specialist uses, likes of ND or polarisers.

For protection and improved contrast, lens hoods are the way to go.

Yes, indeed. I use hoods on all my lenses, no "protective" filters ever, for my area shooting.

[clackers]

What you think about Didymium filters? Like B+W Redhancer 491 or maybe Hoya Intensifier (Red Enhancer) Filter

As much as I think UV filters are useless for image quality if not actually harmful, Genki, and hoods/caps do a better job of protection, I can understand and do use ND and ND Grad filters to increase exposure times and reduce the sky in landscapes, and polarizers for the glare killing.


Those red filters may work well - never tried them, I'm happy to manipulate the colour channels in post to do B&W.

[Ishpuini]

Those red filters may work well - never tried them, I'm happy to manipulate the colour channels in post to do B&W.

Just to make this clear, a Didymium filter is not a red filter as used in analog B&W photography. (B+W as mentioned is a brand of filters, not short for black and white ;-) )

Didymium is a rare earth glass that has a slightly pink shine to it. When used as a filter it blocks a small portion of orange light in the spectrum. This corresponds with the colour of light emitted by sodium lamps. There are situations where there is a lot of light of that wave length, esp nightly street photography and astrophotography. In both these cases the sodium light might be so bright that it obliterates all detail of other wave lengths in parts of the image. In postprocessing, removing orange will just remove most other colour, since the sodium light just blew the red channel and possibly also the green channel. Using a didymium filter will avoid blowing out these channels, and save the colour of any details that were overruled by the sodium light. In astrophotography it will eliminate much typical city light pollution and help get more detail out of the stars. In other words: in these use cases didymium helps save details that are otherwise lost in the digital file and cannot be recovered in the digital darkroom.

The name Redhancer or Red Enhancer comes from a typical (and more frequent) application in analog photography, esp when photographing autumn foliage. In eliminating some of the oranges, didymium makes the pure reds stand out more, by increasing colour separation and contrast in the leaves. This can indeed be achieved in the digital darkroom nowadays.

hth, Wim

[clackers]

Just to make this clear, a Didymium filter is not a red filter as used in analog B&W photography. (B+W as mentioned is a brand of filters, not short for black and white ;-) )

Didymium is a rare earth glass that has a slightly pink shine to it. When used as a filter it blocks a small portion of orange light in the spectrum. This corresponds with the colour of light emitted by sodium lamps. There are situations where there is a lot of light of that wave length, esp nightly street photography and astrophotography. In both these cases the sodium light might be so bright that it obliterates all detail of other wave lengths in parts of the image. In postprocessing, removing orange will just remove most other colour, since the sodium light just blew the red channel and possibly also the green channel. Using a didymium filter will avoid blowing out these channels, and save the colour of any details that were overruled by the sodium light. In astrophotography it will eliminate much typical city light pollution and help get more detail out of the stars. In other words: in these use cases didymium helps save details that are otherwise lost in the digital file and cannot be recovered in the digital darkroom.

The name Redhancer or Red Enhancer comes from a typical (and more frequent) application in analog photography, esp when photographing autumn foliage. In eliminating some of the oranges, didymium makes the pure reds stand out more, by increasing colour separation and contrast in the leaves. This can indeed be achieved in the digital darkroom nowadays.

hth, Wim

Thanks, Wim, this sounds like another entirely worthy filter!

[Genki]

As much as I think UV filters are useless for image quality if not actually harmful, Genki, and hoods/caps do a better job of protection, I can understand and do use ND and ND Grad filters to increase exposure times and reduce the sky in landscapes, and polarizers for the glare killing.


Those red filters may work well - never tried them, I'm happy to manipulate the colour channels in post to do B&W.

Hi, ND filters are nice, but have so many with different graduation like the polorizers filters, which one are more useful, a regular circular polarize or circular polarize with graduation?

[BigDave]

I looked through the listings for graduated Circular Polarizer, and I did not really find any. This would be kind of contradictory anyway as I see it as a polarizer needs to be rotated to achieve the best image. A graduated filter needs to be place vertical or horizontal (generally) to achieve the exposure effect necessary. Rotating the graduation WITH the polarization would not allow for the proper image composition and control.

[clackers]

polarize or circular polarize with graduation?

What's a graduated polarizer, Genki?

Do you have a link to an example?

[Genki]

What's a graduated polarizer, Genki?

Do you have a link to an example?

Heliopan 58mm Circular Polarizer Lens Filter 705841 for Digital Analog ES58 4014230808585 | eBay

[clackers]

Heliopan 58mm Circular Polarizer Lens Filter 705841 for Digital Analog ES58 4014230808585 | eBay

Oh, what's graduated about it?

[BigDave]

I see the marking on the side, this looks to simply be a circular polarizer (a good one too). From the images, it is not graduated (top to bottom/side to side), but the polarization effect can be adjusted, as with most any polarizer now.

Regards,

[Na Horuk]

(snip) In addition to that, for collision protection I find a hard lens hood much more effective, esp on long lenses. Other filters that might be useful are filters that achieve results not possible in post processing. I'm thinking: - Infrared filters for near-infrared photography (my wife hates this...) - Polarizers for eliminating reflections (not for anything else to my feeling) - Didymium filter, which cuts out orange sodium light, which can improve night street photography in general and astrophotography near habitation more specifically - ND filters: to lengthen exposures. There may be others, but the above is what I use...

Nice info! (Edit: Note to readers, check the original post that I am quoting here, as there is a little more info there. I cut the post so the quote isn't as long)
There are also special effect filters, like crosshatch filters and variable colour filters. These have limited use, because they quickly become gimmicky. But they can add special effects that might not be possible in post (at least not as well-done, not with a quick Photoshop thingy).
And also macro filters, though few brands actually make good ones. Raynox is one that is often mentioned as best out there.

I basically stopped using UV filters and even the cheap polarizer I had. Upgraded the polarizer to a Hoya HD polarizer, which is pretty great. I think I'm pretty much done regarding filters. Many filters have a premium price tag, but look at reviews first. I chose Hoya HD because it is the latest upgrade to this technology and it was fairly priced.