Skylight or UV

[smac]

Seeking advice....which is the best filter to use to protect your new (expensive) lens. Sykylight or UV.....do you keep it there permanently or are there some photograph situations where you would remove it?

Stuart

[Killakoala]

They are one and the same. Same thing, different names.

Plenty of phots keep them on lenses to protect their investments. It comes down to personal choice.

If used at night, the UV filter will cause some difraction of light and cause bright lights to have streaks eminating from them. This can look good or bad depending on the shot.

If doing landscapes i would recommend using one to help cut down on haze.

[smac]

Thanks Steve.......just the advice I needed..

Stuart

[sirhc55]

UV filters absorb UV light and are clear glasses. Skylight filters are coloured glasses and usually have a touch of pink. In addition to absorbing UV light, the pinkish color of a Skylight filter can also counter the excessive blue color of the sky in a sunny day, and produce a warmish tone.

Haze is caused by dust particles in the air. These particles reflect shorter wavelengths more than the longer ones. Thus, UV is affected the most, followed by blue, followed by green and red, and the recorded images will be not very sharp and look hazy. Haze filters are designed to reduce haze and are yellowish to counter the excessive blue. For example, Tiffen Haze 1 reduces excess blue and transmits 29% at 400mm wavelength, while Tiffen Haze 2A provides greater ultra-violet correction than Haze 1 and transmits 0% at 400mm wavelength. However, for color photography, polarizers are frequently used. Note that although polarizers many not cut through haze as effectively as Haze filters do, polarizer can increase the contrast of the scene by eliminating reflection!

[robboh]

Me, personally, I dont bother. If I were shooting rally's or something, then yeah Id put something up front to protect the front element, probably a Skylight 1a filter. It would also have the added benefit of warming things up slightly. How they effect the metering or WB on a D70, I have no I idea.

[ElRonno]

Hi Smac,

A skylight filter is slightly pink like mentioned by sirhc55. If you use the custom WB you can compensate for that though

Keeping a protection filter on the lens is a good thing for everyday use. If you drop the camera, or the lenscap falls off in your bag or anything you'll be thanful for it. And the flat glass is easier to clean if gotten wet or dusty. And if it gets scratched from cleaning after a sandstorm, just throw it away and buy a new one.

However... your image is only as good as the weakest link. Be sure to buy a good one and take it off if you need a tack sharp portrait (and you are in a safe place ).

If your lens is designed with the front lens set backwards to prevent light reflections, you are rendering the whole idea useless by sticking a piece of glass on the front. So be sure to add a hood!

Oh, and if you let someone else take a picture with your camera, you should certainly add TWO filters just to be sure! Oh, I wish I had put at least one on that 35-70 2.8D... Now serving as a paperweight.

[Yamahauler]

ElRonno, Got a greenbean question for you. What do I use to determine a quality uv filter from a low quality filter?

[ElRonno]

Hi Yamahauler,

Just look at some filters up close and you'll notice a few differences. Just like with corrective spectacles, there a lot of different materials and coatings. Don't be neurotic about specifications, just have a pragmatic look yourself.

Image quality: Put some filters on a sheet of white printing paper. Rule out any filter that that shows a colour cast to the paper beside it (low quality glass or plastic "optical resin" with a brownish cast). Then look at the paper texture and throw out the ones that make it look less visible (that eliminates the cheap plastic ones). Theoretically, you could test it in more detail, but no one will see the difference anyway with everyday photography (remember to remove filters for special things like portraits and macro).

Behaviour: try the lens in difficult situations to check out the reflections: shoot in bright (sun) light, sun falling in from the side. Or try a reflective object (chrome piece of a car maybe) to see what happens. The less flare, the better!

Usability: distract the sales person and secretly put some dust on the filters (or shake your head in case of dandruff). Now see which filter (coating) allows you to blow it off easily. Then do the same with wiping. If you want to take the risk, do a fingerprint test Next, see if it rattles in the fitting. For larger diameters you might want to choose a brass fitting as brass has less thermal expansion so your filter will not get stuck on the lens.

The trade off is that the better the filter is coated, the better the behaviour and the more problematic the cleaning! Clean, pure, flat glass is easy to clean, but reflects too much light! Coatings make the surface a little rough and a pain to clean. It's your own call where on the balance you would like to be. Do you throw your camera around and take a million pictures or do you treat your camera like a baby only to remove the lens cap for an instant masterpiece?

I'm in the first category and use a lens hood to both help fight reflections and minimize the change of getting fingerprints on the filter. And to absorb to blow if all that stuff slips through my hands