300mm f/4D ED-IF AF-S

[dk]

I wasn't sure exactly where to post this topic.

I am still considering which telephoto to purchase (weeks now). It hasn't been an easy process. I keep going back and forth between the one listed in the subject line and the 80-200mm f/2.8. I'll be shooting more sports; races, equestrian events. I'll mostly be outside, lots of light (makes me lean toward the 300mm f/4). I've read hundreds of reviews and just this morning learned about the 39mm drop-in filter on the 300mm. I can't seem to find any info on the specifics. My question to the forum is this; under what circumstances would I use this filter or is it something I would use in every instance? I can't remember what the filter are made of, but are they expensive?

Thanks a million.

dk

[gstark]

The filter is a part of the optical system and must be in place all of the time. You can replace it with other 39mm filters if you wish.

Being 39mm, no they're not overly expensive, but it is included with the lens when you buy it.

So, just forget about it. it's there, and it's not a concern.

What is your need in terms of reach? Will the 200 be enough? do you have, or are you considering getting, a TC?

[dk]

Thanks Gary. I'm leaning toward the 300mm f/4 and when I look at sample images on pbase I find the reach will be more than adequate. I am also considering a TC to extend the reach to 420mm. Please forgive my ignorance on this subject; is the drop-in filter glass?

dk

[gstark]

I've not subjected mine to a Wendelling (tested it till it breaks) but I believe so: Nikon optical glass, even.