'protector' filters for Leica M lenses

[steven_sherwin]

Currently I use UV filters on my M lenses out of both (bad?) habit and in the belief that they 'protect' the lens. I shoot

mainly b&w street work and was wondering if my images 'lose' anything as a result of using these filters. Apologies if

this question has been asked before.

[saskphotog]

They do. Whether you can see it or not is another question.

 

There will be many situations where the effect is invisible, but there are lots of situations where it will be very likely you will get visible effects from the filter.

 

In over 40 years of photography I have never had any damage to a lens that a filter would have prevented. I use filters only for specific effects like polarizing and ND filters.

[Ed_Ingold]

The optical quality of certain filters (e.g., B+W, Heliopan and Hoya) is as good as nearly any lens. Loss of sharpness, at least at normal shooting distances, does not seem to be a problem. However you can incur a substantial loss of contrast if there is a strong light shining on the filter, even outside the normal field of view. Even a bright background may cause a problem. A coated filter helps but does not eliminate this effect.

 

If you carry your camera where it might get bumped by other people or equipment you're carrying, use a protective filter AND a lens shade. If you work in more controlled conditions like a studio or nature, and want the highest image quality, then forego using a filter (except for effect).

 

For "street work", I'd use a filter. There's the danger of accidental contact with people, doors and such, and there is less emphasis on technical image quality.

[sarah_fox]

Frequently discussed here.

 

If you've never fumbled a lens cap or touched your lens with anything but a lens brush or cleaning cloth, then you're probably safe without a filter. Personally, I'm not that good, even though I'm not a careless or clumsy person. I use Pro-1 filters, and I think their adverse impact on my images are negligible to none.

[gordon_lukesh1]

If I don't have my orange or red filter on, I got to UV. I have never noticed any effect myself. Maybe I need new glasses?

[leicaglow]

Just use a very good filter--one where the glass surfaces are very parallel and the glass quality is high quality. Loss of sharpness or not, I'd never shoot without one to protect the lens. If you filters get dirty, so too would the lens. I always try to use a shade as well for protection against knocks and dings.

[sarah_fox]

FAIW, I just cleaned four camera outfits while watching a movie. They belong to four different people, two of whom used protective filters and the other two of whom did not: All are one-owner outfits, purchased new, by people I know well and whose habits I know.

 

The Canon AE-1 Program outfit was the one with the protective filters. It was surprisingly dirty and was used by a gentleman whose gracefulness was not his strongsuit. The 50mm lens, which was the most used lens and the one on the camera, was perfect, once I got it cleaned up. Very nice lens.

 

The Minolta SRT101 outfit was used much less and did not employ protective filters. It was purchased long ago, new, by a college student. The 50/1.7 was the most used lens. The 135/2.8 and 28/2.8 spent a lot of time in their cases. The 50 "looked" fine and was a nice lens, but it glared/flared quite a lot more than the 28 or 135 when I pointed it towards a light in the room. I first thought the problem was in the viewfinder but discovered otherwise once I mounted up the 28 and the 135, which were contrasty and had almost no flare. The lesson from this outfit was that the greater use of the 50 had resulted in a lot of microscopic surface abrasions that I couldn't even clearly see, resulting in a lot of flare.

 

The Leica IIIf also had no protective filters. The outfit has a Leitz 28, a Leitz 50, a Nikkor 85, and a Steinhall 135. Primary use was of the 50. Secondary use of the 28. The 90 and the 135 hardly ever got used. All lenses looked quite good. However, when held in the light, some flare was evident in the 28 and 50. The Nikkor 85/2 (a gorgeous lens) was perfect, as was the Steinhall. Again, there were no obvious "scratches," and the lenses all "looked" perfect. However, more intense light revealed flare issues.

 

Finally, the Pentax Spotmatic F outfit with an SMC Takumar 28, 50, and 135. This one is mine, and I used protective filters. Primary use was of the 50, and I did use it a LOT. All the lenses look as great as the day I bought them, and flare is virtually nil.

 

So there you have it. Virtually imperceptible abbrasions will take their toll over the years on an unprotected lens. The two owners (above) who did not protect their lens were careful with their equipment. In fact the Leica owner (my mom) was down-right compulsive about it. However, despite their best efforts to protect their equipment, fumbled lens caps, more frequent cleanings, and other mishaps did take their toll.