Help with lens converters please

[kayicolyn]

Please help, i am looking for a telephoto lens for my lumix G3, I was advised by you knowlegable people here to get either a Olympus 75 300mm or a Panasonic 45 200mm.
I have come to the conclusion that the olympus would be the better option (please correct me if im wrong) as this is the better zoom length, and as i will be mainly shooting wildlife and scenery this is the one i need. However I have hit a problem as I am not sure what type of lens converter I need, would any work or do they need to be specific to each lens type ?
Thanks in advance
Andrea

[inkista]

Not sure I'd recommend using a teleconverter with either of those lenses.

Generally speaking, a 1.4x tc adds one stop to a lens's maximum aperture, and a 2x tc adds two stops. When a lens's max. aperture hits f/8, most consumer-grade digital camera bodies stop autofocusing. So you only want to use an 1.4x tc with an f/4 or faster lens, and a 2x with an f/2.8 or faster.

Both of the lenses you've listed are f/5.6 at the long end. That makes them an f/8 and f/11 lens with a 1.4x and 2x tc, respectively. So no autofocus, or compromised autofocus performance. This happens to me on my Canon with my EF 400mm f/5.6L USM and a 1.4x tc.

Also, be aware that TCs, while they do add magnification, also tend to add softness. And the higher the magnification, the worse it gets. It's nothing like actually having a longer lens.

[kayicolyn]

im not sure if i mean a teleconverter, i think i mean an adapter as the lenses i mentiond do not fit onto my camera so i need to find something that will allow me to use various lenses.
I am new to photography and after wading through pages of info on photography, still dont understand much of the lingo, so please could you speak in simple terms.
thanks

[inkista]

Yes, adapters is for switching mounts. A teleconverter is for changing the focal length of an existing lens.

This is just me, but if you're going to buy new lenses, not used ones, then you might as well just get lenses that fit. The mount system you're looking for is "micro four-thirds" and both Olympus and Panasonic make lenses in that mount (as well as lenses that are not in that mount). The lenses that have been recommended to you are probably micro four-thirds lenses. These would not need any adapter, and would be considerably easier to use than an adapted lens.

Micro four-thirds is distinct and separate from a related mount, "four-thirds", which are the dSLR lenses and cameras made by Olympus and Panasonic. If you want to get a four-thirds adapter for mounting four-thirds lenses on a micro four-thirds camera, Olympus makes and sells one (MMF-2), and it retains full electronic communication between the body and the lens. Not sure if Panasonic makes one.

If you want to adapt a lens that isn't four-thirds to the micro four-thirds mount, you'll lose electronic communication, and that means you won't have autofocus, aperture control from the body (you can only shoot in M or Av, and you have to use stop-down metering--this is where the viewfinder will actually get dimmer as you physically stop down the lens to accurately meter; not the wide-open metering the camera can do by default when it can control the lens aperture), or full EXIF fields. Generally speaking, you really only want to do this with old vintage film camera lenses that don't autofocus anyway, and only if you can put up with all the PITAness of shooting Manual all the time.

[kayicolyn]

Thank you inkista, you have realy helped me out there, i kinda understand a little more now. I am going to buy new for sure, now I have teh information from you I won't look silly in the shop lol.
I will keep you informed on which one I choose, thanks again.