Originally posted by ripit Isn't that what it is for rear mount teleconverters that go between the lens and the camera? I was referring to front mount teleconverters that screw into the front filter threads of a lens. I was under the impression that if they could gather enough light they would not lose light? I was wondering how focal length and sensor size might come into play if at all though?
This is the lens that I have on the way from ebay.
Century Optics 1.6x Tele Converter, Panasonic AG-DVX100 0VS16TCDVX
If its anything like the similar century optics wide angle I got (the bigger one anyway), it is just huge and weighs about as much as a brick. The 105mm front dimension leeds me to believe it may be that big.
Oh, like magnifier attached to the front of the camera? Those will degrade your image quality noticeably, but you're right, the light loss won't be as significant. I believe the new max. aperture value can be calculated using the (ratio of the magnification over the new front element diameter) times the original focal length, though I'm not 100% sure. If you then compare that to the original max. aperture, you'll be able to roughly calculate the number of stops of light loss. The calculation is only an estimate because there might be some additional light loss because of the extra glass element(s) in the converter.
In any case, if the new front element size is big enough, it can make up for most of the light loss associated with the magnification.
Adam
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