Thanks guys, I just drowned my 2nd Panasonic TZ3 and I'm wondering if I should get a Canon for a change.
Btw, the TZ3 has a 10x lens and it doesn't get in the way; but then it's true that I only use the widest setting (28mm).
OK, your TZ? has a 10X lens. Let me ask you this, what exactly is it that you are trying to improve upon, in particular regarding underwater photography?
IMO, others can disagree, I don't care, I have found several things to be of paramount importance to underwater photography:
1. Getting close. Getting close requires a wide angle lens. You cannot mount an accessory wide angle lens on either your Panasonic or the Canon 130IS so exactly what have you improved there by getting the Canon?
2. External strobe(s). Almost a necessity for anything beyond casual snaps and especially in water with floaties and turbidity. Do either of these cameras have manual strobe control and manual power selection?
3. Did I mention getting close, OK, define close, less than 5 feet and preferably no more than 3 feet. Therefore, to preserve any field of view to encompass your subject, macro aside, a wide angle lens must be used. Define wide angle lens, OK, greater than 100 degrees diagonal field and preferably more like 120 degrees to 180 degrees so that you can get in CLOSE and still have sufficient area to grasp the subject.
If you purchase, over and over, what you had before and use it just as you had before, what is the gain, improvement you are expecting?
BTW, the 28mm Canon lens through the flat port is not wide angle, not even close, there is only about a 60 degree diagonal FOV or roughly equal to a 35mm lens above water. The three lenses I use on my FIX/Canon S90 yield a DFOV of 130 degrees, 150 degrees and 165 degrees more or less plus my macro lens.
In this example, Canon S90, FIX, dual Inon strobes, Fisheye UWL-04 lens, my wife is about 6 feet away, the sponge in the foreground is about a foot away, with the 28mm lens and flat port, I would have needed to be back about an additional 6 feet.
This pool shot, for FOV only, 28mm though flat port:
Shot from exactly the same place with the same camera but with the Fisheye UWL-04 accessory lens installed:
Why does this matter? In order to eliminate the typical bluish "fish picture" you must get close, the only way to get close and preserve FOV is to use a wide angle lens, you cannot do that with either camera you mention.
My rendition of a bluish fish pic, 28mm flat port, shooting distance about 12 feet (Canon A570):
Similar photo, distance about 4 feet but with wide angle lens installed (Canon A570):
Oh, the cameras I mentioned have RAW.
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