I finally got a Panasonic LT55 telephoto lens and LA5 adapter for my Panasonic FZ150 camera. I took several photos of subjects near and far using a tripod and a remote switch. (I highly recommend a remote switch if you use a tripod!)
I took the photos with the camera's "Conversion" setting set to telephoto lens. This automatically zooms the camera lens out to its maximum 24x optical setting inside the LA5 adapter tube which screws directly onto the body of the camera. The LT55 lens then mounts on the end of the LA5 tube positioning it near the end of the camera's zoomed out lens. This setup keeps the weight of the telephoto lens off the camera zoom lens mechanism.
I took shots with the LT55 lens in place followed by trying to get equivalent shots using the FZ150's digital zoom feature only without the lens. While I tried to match shots exactly, you will notice my attempts are not perfect. However, I think you can see how the LT55 lens performed versus using digital zoom only. I used fine quality JPEG format for all shots. I have not made a comparison using RAW format yet.
I posted several comparisons on my Flickr site. The pictures taken using the LT55 lens have "lens" in the name. The equivalent pictures using digital zoom only have "dig" or "EZ" in the name.
Here is the link to the Flickr site with the lens versus digital comparison shots:http://www.flickr.com/photos/smhamilton ... 354286184/
THE BOTTOM LINE is I could see little or no advantage in using the LT55 telephoto lens. I almost always got better pictures using the FZ150's digital zoom only. In fact, if you drop down from the maximum 12M picture size, you can take advantage of the "Extended Optical Zoom" (EZ) feature. This is supposed to digitally extend the camera's actual 24x optical zoom without “deterioration” in the picture quality. I have to say this certainly seems to be the case. I got much improved long distance pictures using this feature.
The only time I thought the LT55 lens improved the picture is in the case where I also added digital zoom to get a total magnification of about 108x. Matching the same magnification using digital only was not as good. Pictures 452 and 455 in the Flickr site are an example of this. Mt. Baldy is about 9 miles away.
Earlier I had tested a Digital Optics 2.2x lens. The Panasonic LT55 lens is better, but still not up to the quality you should expect in my opinion.
I hope somebody can tell me if I am doing something wrong so I can get better results!
MORE INFO ADDED (4/5/12):
I have found that the LT55 lens does improve pictures when you go beyond the Extended Optical Zoom (EZ) offered by the FZ150 in reduced picture size settings. I started using a setting of 16:9 aspect ratio with a 6MEZ picture size. With this setting, EZ goes to about 40x. Total zoom power is hard to determine. I have found that what the camera says when zooming and what the zoom is based on 35mm focal length shown in the picture properties don't seem to match. AND, the amount of digital zoom is only given to the nearest tenth. Also, I question if the LT55 lens is really giving 1.7x when mounted using the LA5 adapter.
Let me try to explain what I did a little better. I mounted the LT55 lens and let the camera zoom out to the EZ of 40x using the above settings. The resulting picture should be about 68x total zoom. Then I removed the lens and added digital zoom to the EZ of 40x to get a matching picture size to the one taken with the lens. When comparing those two pictures, the picture with lens seems to be better. This tells me the lens does a better job then digital zoom by itself, which is what one would expect. However, if you take pictures where the desired total zoom falls within the Extended Optical Zoom (EZ) or Intelligent Zoom range, then the camera does better without the lens I believe.
I have added comparisons to my Flickr site above for you to review.
MORE ZOOM EXAMPLES - YELLOWSTONE PARK (6/9/12)
I added few more examples of pictures taken to my Flickr site. Pictures pairs 2 & 3 and 4 & 5 show pretty spectacular (I think) examples of the zoom capability of the camera going from 1X to 32X (iZoom). It was cool and windy which made it clear.
The rest are samples of shots I took along the way. As I said, it was windy, so some shots were really hard to get, especially when using full zoom. The camera actually picked up more than I could see when taking some of the pictures and they turned out better than I expected. See Flickr link below:http://www.flickr.com/photos/smhamilton ... 097164086/