Best compact macro setup?

Hi folks!

As discussed here , I've recently upgraded my rig from Olympus C-7070 to Canon S90. I fell in love with macro prohotgraphy and I need to find the optimal compact macro setup. I am not sure should I keep my S90 because of some of its limitations. So here is arsenal of question, please share your experience and knowledge!

• S90 lack flash hot shoe. Will slave digital flash be accurate enough for good shots or do I need hot shoe compact for example G11?
   
  
• S90 has 1/1.7" censor and its closes focus distance is only 5cm. I took a photo of ruler as advised here, and calculated magnification ratio of 1:8.55. Not quite macro . However, G11 can do supermacro up to 1cm, so I could imagine magnification factor will be something like 1:2 which is way better. But using your external flash to lit your subject 1cm from lens is probably impossible. What is your experience about very close up macro photography with external flash? How close can you get a good photo?
   
  
• There seems to be various diopters and underwater conversion lenses (for example Inon UCL-330, Inon UCL-165AD, Inon UCL-165M67 Macro Lens). What is their pros and cons? AFAIK dipters will soften image edges? Please list all diopters or macro extension tubes you know for uw compact photography and share you experience.
   
  
• One external flash should be enough for macro photography and its harsh shadow can be softened with reflector. Any experiences of such reflectors?
  

Well, it's very confusing to use "1:1" unless you know sensor size. I'm used to 1:1 using a FF equivalent - meaning 1:1 is 36mm across :-)

I think the close focus distance of the camera just doesn't matter. You can't take a photo of something 1cm in front of the camera anyway.

A flash hot-shoe is not required. Since the flash mode defaults to MANUAL on both those cameras when you put them in M mode, you have to set your external flash power yourself anyhow.

The INON closeup lenses are VERY good and you can stack them to get ever more magnification. I remember a guy who used to stack them w/ great results. Yes, you will get more and more chromatic aberration the more "light bending" you do.

One external flash is fine for macro - but two is better :-) You can get some of the older ones on Ebay for very little money (example Sea and Sea YS30)

Cheers

James