Re: [Leica] Summilux-m 35mm f1.4 asph & uv filter

[Five Senses Productions <fls@5senses.com>]

I wholeheartedly agree.....I am also anti-filter.  One of the best features
of the 
Leica lenses is that they have UV protection built-in.  Jim is right, keep
your
lens cap on you're ready to shoot!

Francesco

At 10:54 PM 1/24/98 -0800, you wrote:
>You can probably answer your own question. In order to realize the answer,
you
>really need to think about the situation. Not just have the answer blurted
>out.
>If you get stuck, just ask and I'll gladly help.
>
>1. Do you know why Leica (and all other major lens manufacturers) has
spent an
>enormous amount of research time and money, developing and purchasing very
>expensive, hi-tech, very sophisticated, multicoating apparatus, to multicoat
>the FRONT element of your exquisite lens? 
>
>2. Do you know what the purpose of this coating is? 
>
>3. Other than optically transparent glue, do you know what other chemical is
>with the glue between the lens elements? 
>
>4. How much does a UV filter cost? 
>
>5. How much did your lens cost? 
>
>6. What does a UV filter do for you?
>
>7. And last, but not least, why do you have a UV filter on your lens? 
>
>
>
>At 09:31 PM 1/25/98 -0500, you wrote: 
>>
>> I am using the 35mm summilux-m f1.4 asph with the Leica uv (13004) filter.
>> Someone told me
>> that I was loosing the sharpnes of the lens with that filter. Any comments
>> from users?
>> I always beleived good quality uv filter did not altered the quality of the
>> lens.
>
>
>
>Answers:
>
>1. & 2. So that when the rays of light, emanating from the subject, (whether
>the sun, moon, or people) and kiss the front element of your lens, they will
>pass right on in, without reflecting off of the surfaces of the elements
>causing flare. Flare can be simply a slight reduction on contrast, sometimes
>un-noticed. But there. Sometimes it's like white wash over the entire image.
>Producing unusable photographs.
>
>3. A UV inhibitor so that a UV filter is not needed.
>
>4. much less that $100.
>
>5. More than $1000
>
>6. Reduces your $1000+ lens to the quality of your $100- filter. The front
>surface of a filter WILL NOT INHIBIT FLARE. The front element of your
>expensive
>lens WILL INHIBIT FLARE. You paid dearly for this anti-flair coating. See
1. &
>2.
>
>7. Use a lens cap. That's what it's for.
>
>Jim
>
>ps... the LUG old timers know I take a hard line with filters. I personally
>use
>filters a lot. BUT... I use a filter only for a particular purpose.
Polarizer,
>warming, ND Grad, color grad. There must be a useful purpose for me to render
>my expensive front element useless. When you have a filter on your lens. DO
>NOT
>let a single ray of direct sunlight hit the filter. You will have some
>level of
>flare. Guaranteed. M cameras work best with no filter because, while
street or
>other hand held shooting, you cannot guarantee that stray bright light will
>not
>hit the filter. 
> 


Francesco Sanfilippo,
Five Senses Productions
webmaster@5senses.com

http://www.5senses.com/