[lesmore49]

I just bought a DA 70mm F 2.4 (Silver) about a week or so ago.

I have a 49mm B+W filter I would like to put on this lens, to protect it. B+W of course are very good filters.


Question # 1 :

I have read the instructions and tried to affix this filter to the lens...but so far without success.

Any suggestions as to where I'm screwing up ?


Question # 2 :

The age old question...to do or not to do ....should I put a filter...clear or UV....on a lens ?

I have about 9 modern Pentax lenses and on every one of them...except my Pentax 10-17mm Fisheye...I have put a top quality filter on the lens. So far...I have noticed no difference in photo quality...with and without...filter.

The 10-17 of course...because of the design and the protruding front glass of the lens...makes it impossible to put a filter on this lens. But so far...almost 3 years later...I notice (touch wood) no scratches on the Fisheye.

So whaddya think ? Should, if I can, put a filter on my new DA 70 Ltd. ?

Thank you for your input.

Les

[Adam]

Any suggestions as to where I'm screwing up ?

Where are you trying to mount it? It goes right on the outside of the lens, before the hood, I believe.

The age old question...to do or not to do ....should I put a filter...clear or UV....on a lens ?

If you have a high-quality one, then I would hesitate to use it just to protect the front element. Some cheap UV filters actually degrade image quality, so you don't want that.

[jatrax]

As Adam says you have to remove the hood, put the filter on, and then screw the hood onto the filter.

Without trying to open the filter/no filter can of worms, I will say that on the DA 70 I think the hood is more than enough protection. Even retracted it sticks out about half an inch and the front element is so small I am not sure what would hit it anyway, tucked in like it is.

[Mareket]

I reckon a lens hood will give you the protection you're looking for without the IQ loss of a filter. I generally use a hood for protrection more than for flare resistance or whatever. But then it's much larger, so choose between size and IQ. If something hits the filter and shatters it your glass will be at risk, and Pentax's SP coating is really good at keeping dirt off a lens anyway. Lens hoods can also be cheaper than a good filter, so if it cracks it's easier to replace, and plastic is less likely to damage the lens, metal less likely to snap (but might dent).

And yeah, with the 70mm you take the hood off and screw the filter straight on to the front of the lens.

[lesmore49]

Where are you trying to mount it? It goes right on the outside of the lens, before the hood, I believe.That's where I'm trying to mount it.




If you have a high-quality one, then I would hesitate to use it just to protect the front element. Some cheap UV filters actually degrade image quality, so you don't want that.

The B+W I have confidence.

[lesmore49]

Jatrax and Mareket have both mentioned the 70mm's hood as protection enough. I am thinking that this may be the case. The front element is very small and the hood really adds to the protection...with the hood affixed...the 70mm's front element is almost in a cave.

[psychdoc]

The DA 70mm is the only lens I dont have a protective filter on- due to the built in hood that is relatively large.
Although I often dont keep one on for the DA 15.

[mikeSF]

some would have you believe there is no use for protection filters. I, otoh, have shot in enough situations (ocean spray, sand storm, close dogs, kids, thorn bushes, etc) to attest to their usefulness. Don't get me wrong, I wont use a filter in most cases, especially at night, but when i need to slap it on, i am glad i have them in my bag.
It only takes a single grain of sand to wreck the front element of your favorite lens. Which would you rather replace??