why use a uv filter

sikahunter

hey why should i use a uv filter please advise

.Longshanks.

Short answer - to protect lens from accidental damage
Longer answer - others will explain:D

5uspect

They can reduce haze on sunny days.
http://photo.net/equipment/filters/
Another reason is to protect your lens from damage.

sikahunter

cool thank see i got a sigma 70-300 dg macro lens it came with it so waas just wondering what its for and why i should use it im just getting into photograhy only have the cam 2 weeks

5uspect

Well now that you know what it does get out and experiment!

Mycroft H

Good article here:

http://photo.net/equipment/filters/

Paulw

5uspect wrote: »

They can reduce haze on sunny days.

UV shouldn't effect your image at all, if the filter is any good.

A polarising filter should be used to reduce haze.

5uspect

No, UV filters remove blue UV haze.
But not so much on digital:
http://www.cambridgeincolour.com/tutorials/camera-lens-filters.htm

sikahunter

hanks for all your repleys:D

Fajitas!

Best reason I can think of

5uspect

Is that ice, looks like you stuck a pint on your camera.

Fajitas!

Hah, not ice, just the UV filter, and yep, it's about the width of a pint glass... All the more expensive to get repaired if it was the front element instead of the filter

Fajitas!

Fajitas! wrote: »

Best reason I can think of

Unhappy bokeh day?

5uspect

Fajitas! wrote: »

Hah, not ice, just the UV filter, and yep, it's about the width of a pint glass... All the more expensive to get repaired if it was the front element instead of the filter

Indeed. At least you got a nice shot out of it.

AnCatDubh

why? because it increases the attraction of the opposite sex infact you should use 2 if feeling really lucky!

seriously - offers protection if you need it from knocks and breakages. i'm less convinced as to its ability to produce better quality images but im happy to be proved incorrect.

stcstc

i actually dont use them

1. the protection they offer is relatively limited, a decent hood on a lens will generally offer as much protection

2. even a good quality filter is still a cheap piece of glass / plastic compared to whats in a decent lens, the lens manufacture went to great length to produce the characteristics of your lens, you are messing with them adding the filter.

BUT

this is my opinion, and not shared by everyone

Fajitas!

Well, a lot of people debate the affect it has on quality, but tbh, I've shot both, and at 100% crops, can never see the difference.

In a 'taking the piss' act, I took a few photos with the cracks shown above (actually, much worse, I had to take a lot of glass out to get it down to that) and the shots were 99% as sharp as normal, with the tiniest bit of glow around the cracks when I was down to pixel level - I'm sure if I was shooting f/6.3+++ it'd show up more, but below was just fine on it - And that's with a shattered UV filter!

What happened to the above wouldn't have been saved by the 135's hood, though, it could have made it a bit worse :-/

Both work best imo

Mycroft H

Arent some lenses optically designed to use filters?

CabanSail

I use UV Filters to protect the lens. Have had a UV Filter scratched, which was better than it happening to the front element. I also have (well someone else is using it now) a CPL that was chipped but saved having the damage to the lens. Then again I don't use the Lens Hoods.

The only lenses I don't have UV Filters on are my two primes. On the 50mm f1.8 as the front element is really well recessed & the cost of a quality filter is a significant part of the replacement cost. The 85mm f1.8 is for studio use & so it should not get exposed to the dangers of damage like a lens being used outdoors.

mikeanywhere

Fajitas! wrote: »

Best reason I can think of

Exactly the same thing happened to me a good week back, I wasn't a happy bunny until I realised the glass I could hear rattling around was the UV filter only. *big big sigh of relief*

Fajitas!

Same as! I did have to use a bit of DIY to get it out, but hey - Better than having to get the real glass out. I was just thankful it happened about 10 minutes after a fashion show, rather than before it!

sineadw

always ALWAYS filter and a hood! Al that's scary...

cnocbui

I have been using cameras for over 40 years and have never smashed or even scratched a front element.

Filters will degrade the quality of the image from a high quality lens, in most cases, so why buy it in the first place if you are going to lower it's performance with a filter?

Might as well buy a cheaper lens and use it without a filter.

Fajitas!

cnocbui wrote: »

I have been using cameras for over 40 years and have never smashed or even scratched a front element.

Filters will degrade the quality of the image from a high quality lens, in most cases, so why buy it in the first place if you are going to lower it's performance with a filter?

Might as well buy a cheaper lens and use it without a filter.

I've been using cameras for 6/7 years and I've gone through several filters. Different people have different needs, but I'm a lot more comfortable with a filter on my camera.

The amount a UV filter will take from the quality of a lens is absolutely minimal and more often than not, unnoticable, especially if a good quality filter is used. For the sake of protecting my front element from sand, mud, salt water, grit, dust, rain and birdsh*t, along with the scratches and breaks, I don't mind in the slightest.

cnocbui

Fajitas! wrote: »

I've been using cameras for 6/7 years and I've gone through several filters. Different people have different needs, but I'm a lot more comfortable with a filter on my camera.

The amount a UV filter will take from the quality of a lens is absolutely minimal and more often than not, unnoticable, especially if a good quality filter is used. For the sake of protecting my front element from sand, mud, salt water, grit, dust, rain and birdsh*t, along with the scratches and breaks, I don't mind in the slightest.

If you feel you have need for them, use them.

Years ago, someone who had scientific training and a great deal of experience with photographic and ther optical equipment, tested pretty much every model of Olympus OM Zuiko lens. In some of the tests he tested the same lens, with and without filters. His results showed variable effects on image quality, from none, to quite significant. Here is the original information:

50mm f/1.4 Zuiko (multi-coated)
OM-2000 with mirror and diaphram prefire; lens with >1,100,000
serial number
Vignetting = D @ f/1.4, B @ f/2, A- @ f/2.8, A @ f/4
Distortion = none

No filter
Aperture Center Corner
f/1.4 B B
f/2 A- B
f/2.8 A A-
f/4 A A
f/5.6 A A-
f/8 A- A-
f/11 A- A-
f/16 B+ B+
Notes: High contrast, except moderate in center at f/1.4, moderately low
in corners at f/1.4 and moderate in corners at f/16; remarkably even
performance across all apertures.

With poorly made Vivitar VMC ND3 neutral density filter
Aperture Center Corner
f/1.4 C- C
f/2 C C
f/2.8 B B
f/4 B B+
f/5.6 A- A-
f/8 A- A-
f/11 A- A-
f/16 B+ B+
Notes: Differences are significant at the 1/3 grade level in this paired
comparison evaluation. Contrast was slightly lower with the filter, but
lower resolution was the most important factor in image deterioriation.
Please note that this particular filter is not indicative of Vivitar or
Vivitar VMC filters, in general. It just tested as a poor sample. Other
filter makers, even the most highly regarded, have been found to have
poor samples in selections taken from used and new stocks of filters.
The use of the term "poor" means star test images, viewed on
a vertical auto collimeter, which show images that are: multiple and
overlapping, fuzzy, off center, and images which rotate when the lens
is rotated. More often than not, only one of these faults are found in
an examined filter. These filters (including the test filter) often look
perfectly good when examined without the aid of instrumentation!

50mm f/1.8 Zuiko (multi-coated, late "Made in Japan" variant)
snip
OM-2S with mirror and auto diaphragm prefire, serial number 5235157,
paired comparison with sample above to examine potential production
variation; identical coating
Vignetting = C @ f/1.8, A- @ f/2.8, A thereafter
Distortion = slight barrel
Aperture Center Corner
f/1.8* B C-
f/1.8 B+ C
f/2.8 A B-
f/4 A+ A-
f/5.6 A A-
f/8 A A-
f/11 A- B+
f/16 A- B+
Notes: Moderately high contrast at f/2.8 and f/8 to f/16, high contrast
at f/1.8, very high contrast at f/4 to f/5.6. * = with an Olympus 1A
filter that "passed" a vertical autocollimator test; lens was
refocused after attaching the filter; no detectable contrast
difference with and without filter.

85-250mm f/5 Zuiko (multi-coated)
snip
OM-4T with mirror and diaphragm prefire, sample 2
Vignetting = B- @ f/5 with filter, A- @ f/5 without, A- @ f/8,A thereafter
Distortion = moderate pincushion
Aperture Center Corner
f/5* C+ C+
f/5 B B-
f/8 B- B-
f/11 B B
f/16 B B-
f/22 ** **
f/32 ** **
Notes: * = with Hoya Skylight filter, which exhibits moderate contrast
images. Moderate contrast at f/16, moderately high at f/5-11. ** = no
SQF or contrast data available at f/22-32.

100mm f/2.8 Zuiko (multi-coated)
snip
OM-4T with mirror and diaphragm prefire
Vignetting = A- at f/2.8, A thereafter
Distortion = slight pincushion (none?)
Aperture Center Corner
f/2.8* D C
f/2.8 C- B-
f/4 B B
f/5.6 B+ B+
f/8 A- B+
f/11 A- A-
f/16 B+ B
f/22 B+ B
Notes: * = with a Canon 1A filter, which exhibits low contrast. Moderately
low contrast at f/2.8 without filter, as well as f/4 and f/16-22, moderate
contrast at f/8-11, moderately high contrast at f/5.6.

Tokina RMC 28-85mm f/4 (multi-coated)
OM-4T with mirror and diaphragm prefire

@ 28mm setting
Vignetting = B @ f/4, B+ thereafter
Distortion = slight waveforming with
moderate pincushion tendency
Aperture Center Corner
f/4 A- B+
f/4* B+ B
f/5.6 A B+
f/8 A- B+
f/11 A B
f/16 B+ B+
Notes: * = with Hoya 1B filter. High contrast images in center and
moderately high contrast in corners at f/4 (with and without filter) to
f/5.6; very high contrast images in center and moderately high contrast
in corners at f/8 to f/11; very high contrast images in center and high
contrast in corners at f/16.

Leitz 90mm f/2 Summicron-R (1978 era 3-cam)
Leicaflex with mirror and diaphragm prefire
Vignetting = B @ f/2, A- @ f/2.8, A thereafter
Distortion = slight pincushion
Aperture Center Corner
f/2* C+ C
f/2 B B
f/2.8 B+ B
f/4 B+ A-
f/5.6 A A
f/8 A- A-
f/11 A A
f/16 A B
Notes: * = Tested with a B+W 010 filter. Moderately high contrast images
at f/2; high contrast images at f/2.8 and f/16; very high contrast at
f/4 and f/11; extremely high contrast images at f/5.6 and f/8. Lens
condition 9+ (KEH=Ex+). Paired SQF grade and contrast comparison to the
90mm f/2 Zuiko Macro test done on a OM-2000, with SQF differences
significant at the 1/3 grade level.

Leitz 90mm f/2.0 APO-Summicron-M
Leica M4-P with cable release
Vignetting = none
Distortion = none
Aperture Center Corner
f/2* B C+
f/2 B C+
f/2.8 B+ B-
f/4 A- B
f/5.6 A+ B
f/8 A- B
f/11 A- A-
f/16 B+ B
Notes: * = with a B+W filter. High contrast images at f/2 to f/2.8; very
high contrast images at all other apertures.
© Copyright 2000-2002 by Gary Reese

cnocbui

To add something I forgot.

Flare with a filter is dramatically increased, as has been shown in many tests conducted by photography magazines. Someone has conducted a simple test here, and included the resulting images, that clearly show noticeable degradation:

http://www.cameralabs.com/forum/viewtopic.php?t=14617&sid=cf3a9350378157744e6d9e50069dc32e