What is the difference between UV and Skylight filters?
I was used to put a Skylight filter to protect my lens, but last time the shop assistant recommended me to use a UV filter instead for Digital SLR.
I though they were the same, only different in "strength" but he told me no, Skylight would introduce false colors in digital sensors.
Is it true?
What's the exact difference between them?
The difference is that a skylight filter is a basic colour correction filter with a slight magenta tint which has a similar effect on skies as a UV filter (which cuts out part of the spectrum), which is neutral coloured. The effect of a skylight filter is slightly warming, overcoming the blue tinge that you get in shadows from the light from a clear blue sky.
The person is the shop is right that a skylight will affect colours but the effect is subtle, can be beneficial and can be largely reversed on the computer. However skylight filters are less common with digital given the ease with which you can apply colour correction in post production.
A more important question is why you are buying a filter. The common advice for protecting a lens doesn't make sense to me, given that filters can exacerbate lens flare and reduce contrast in certain circumstances. The price if a good UV filter can be about the same as a lens repair anyway...
well, for sure once a nikon macro 60 fall by a table. The (40 euro) UV filter was completely broken, but the lens had only a dent in the barrel, it was still usable and they completely fixed for another 50 euro. I doubt that the frontal len could have survived the fall at all.
"given that filters can exacerbate lens flare and reduce contrast in certain circumstances." -> if I have to take quality photo I remove also the filter (or use other filters). But for normal photo tourism I don't see any disadvantage.
There are some falls that a filter will protect you from but many that it won't - filter glass is much thinner that the front element and breaks easier. The point is I've spent a lot less on lens repairs over the years than it would have cost to buy high quality UV filters for every single lens. The image quality isn't a major issue unless you're shooting toward a light source, but you will end up spending a lot on the off chance of preventing damage from a specific size impact.
I still prefer to have a broken filter than a chipped front lens element, and since I use wide angle lenses I have a quite big front lens element
The old "XYZ broke, so this proves that it protected ABC" argument. As false for filters as for cycle helmets. different stability and elasticity just can't be this simply compared, but believing is always stronger (and simpler) then calculating. Btw: I do follow the "protection"-argumenht in case of flying sand (during a race) or other abrasive flying things ... but please spare us your anecdotal "filters protect lenses during a fall" evidence.
I'm sorry, but I've had 2 UV filters save my lenses. Not a large high-impact fall, but a scrape against a wall, and my little lad plus a muddy stick were both foiled by UV filters. mind you, I'm only a novice photographer, so any potential impact of a UV filter is probably lost on me.
@CJM They didn't save the lens, at most they could have saved you from scratches on the front element, which is typically hard and scratch resistant, unlike your filters. By all means use them if they make you feel safer, but I'm confident it's a false economy which is why I advise against it.