I would like to know users opinion on employing proctective filters on leica m-series lenses. Any deterioration of image quality? I have heard that leica designs their lenses in such a way that use of UV/skylight, neutral density filters, etc. are un-necessary for corrective purposes and using them can in effect negatively effect the quality of images rendered. I am usually very careful around the front of my lenses so the protective element, while important, is secondary to the quality of the photo.

-- gene murphy (gene@eval-assoc.com), August 10, 2001

Answers

If you have never gotten wipe marks on a lens and/or it doesn't worry you, then there isn't really any other reason to use a UV filter on modern Leica lenses. I have B+W MRC UV filters on all my Leica lenses because I have wipe-marked some in the past, I shoot mostly outdoors where gritty particles are often blowing around and settle on my lenses, and I am personally satisfied that whatever theoretical image degradation my B+W MRC's cause is below my visual threshold using 20x magnification and therefore of no practical significance.

-- Jay (infinitydt@aol.com), August 10, 2001.

I agree with Jay. I use exactly the same filters. Any effect they have on image quality is less than the effect of everything else that goes wrong.

Of course if you want to cry, wait until something hits the unprotected front element. :)

Art

-- Art (AKarr@aol.com), August 10, 2001.

Hi, Gene: Just for you to get both sides of the image: I own old Leica lenses which look ugly from the front and flare a lot. You have to be very careful if shooting at a close angle with front light. And most of the time you just have to accept the best you can do with them in difficult lighting conditions. Now, don't get misled by my complaints: in most conditions they behave great. I bought them used and their previous owners sure didn't use any kind of protection on them. In the state they are now I don't use anything on them either but care them reasonably. On the average: I think that using protection filters will degrade the quality of your images to a degree that I can't image how could be noticed (we are talking about good quality filters, aren't we?) and, on the other hand, the eventual results of not using them could be easily noticed if they get alike mine. I use filters in all my other cameras/lenses. Just seldom have I found convenient to take them away for a given shoot because of extremely low light. Take care and have fun !

- Iván

-- Iván Barrientos M (ingenieria@simltda.tie.cl), August 10, 2001.

Leica lenses made since about 1965 have a hard protective coating on the front element so that under all but the most extreme circumstances an additional protective layer should not be nessesary. Among my Leica lenses I have some that are over 30 years old and the coatings are in perfect condition. I've had Nikkors which I've used under similar conditions that developed cleaning marks in less than 10 years. Leica also uses UV-absorbing layers on their cements so a UV filter does little besides providing protection.

My opinion is that they're not nessesary but if not having them keeps you from using your lenses, then get high-quality multi-coated Heliopan or B+W filters.

-- Douglas Herr (telyt@earthlink.net), August 10, 2001.

Hi Gene,

I have a mixture of older and the newer generation M lenses and I have leitz skylight filters on all but one. I have never noticed any negative affects. For me it's simply a matter of protection. Leica lenses cost much money and I guess it is just automatic for me to put something over the front element. I'm sure that you can find information saying that a filter can have a negative affect on an image I'm just not sure if the differnce would be noticeable on chromes or prints.

Regards, T Gallagher

-- Tom Gallagher (tgallagher10@yahoo.com), August 10, 2001.

One thing you may wish to consider: If you get a mark or marks on your lens and later wish to sell it you will get much less for the lens, even if the marks do not affect picture quality.

Also, if you are out in dust or rain the filter seems like good insurance. I use Leica UV filters for those reasons.

It really is a personal decision.

-- David Enzel (dhenzel@vei.net), August 10, 2001.

Recently I took a series of shots, on Kodachrome 64, using first one, then two three and four Leitz filters, some UVa and some SL skylight filters. It was difficult to see any differences in any of them with the images projected at four foot width. I think it's worth using them, especially when the scene isn't backlighted.

-- Bob Fleischman (RFXMAIL@prodigy.net), August 10, 2001.

The only thing I don't like about using filters on my Leica lenses is that the lens caps don't fit that well. Especially the current 50 with the built in hood. There will not be any significant loss in image quality from a good filter. Erwin Putts posted that after testing this he found only a 2% drop with top notch filters,(maybe 10% with a lousy one) which is nearly imeasurable. unless you focused perfectly and used a tripod on every shot, you'll never see a difference even examining your negs with a 25X loupe. Only time I remove filters is if I am shooting city scapes at night, as pin point light sources can repeat themselves off the perfectly flat glass. I am careful with my stuff, but I often find after I have been using the camera heavily, stuff does get on the filter.

-- Andrew Schank (aschank@flash.net), August 11, 2001.

I was told by Leitz that UV filters for protection were completely unnecessary and will degrade the image however good the manufacturer. But he said the degradation was very slight with some UV makes but depended on whether B&W or Colour was being used and what aperture and focal length was employed. I questioned sand etc. He said the only problem would be wet sand removal but a good sluice with clean water would be Ok. He said the front element surfaces of lenses produced in the last 20 years are extremly hard. So I stopped using a UV about three years ago.

-- Tony Brookes (gdz00@lineone.net), August 11, 2001.

Gene:

Rather than use filters, you might want to think about keeping hoods on your lens @ all times. Unless you're always shooting someplace where there's dirt, grease, water, etc. blowing around, protective filters aren't very protective & will to varying degrees, no matter how good & multi-coated they may be, degrade your images by increasing flare, especially when you're shooting into the sun or other strong light source (more glass-air surfaces always = more flare). Far better to be religious about using lens hoods, which reduce extraneous light & will protect your front elements.

Just my $0.02, Chris

-- Chris Chen (furcafe@cris.com), August 11, 2001.

Glass filters are not only a potential cause of flare, but they also may create a shift of focus. If I remember well, equal to about 1/3 of the thickness of the filter. That's why large-format shooters focus their image with the filter on the lens, if it is going to be a shot with filter. If you are going to notice these problems in your Leica shots-I think you have to test and decide for yourself. You have to ask why pay for the highest quality optics and then possibly degrade same optics?

I routinely use the shade as suggested by previous responder, and a filter only if it contributes to the shot. Inspect lenses and camera after every shoot and clean as necessary.

A protective UV filter makes sense near splashing salt spray, oil, mud etc. But not routinely as a blanket rule for every shot, in my opinion.

-- Hans Berkhout (berkhout@cadvision.com), August 12, 2001.

I always shoot with the hood on, however I screw on the protective filter only when I really need it, which was around 2% of my pictures for the last year and most of my shooting is outdoors during trekking. Just my opinion.

-- Javier (elrebeco@hotmail.com), August 13, 2001.

I only own one B+W UV filter, and if I remember to, I'll put it on a lens before I go out. I also use a lens hood, and while that does help, if I'm taking pictures at a threshing or tractor show, enough dust gets into the air that I'd rather have the lens protected. If I think there will be flare in the photo, though, I'll remove the filter.

-- Eric Platt (ericplatt@aol.com), August 13, 2001.

i too, bought just one filter and I keep it in it's little container in my camera bag. I will put it on the lens only if i'm in an environment that merits it, such as on a boat, dusty site, beach, etc.

it remains off most of the time.

-- Tristan (tristan@tristantom.com), August 13, 2001.