Close-Up filter & extender Q's

[DolphinV8]

I have a 100mm Marco, and I would like to take close-up pics of my watches. I was wondering what's the difference b/t close up filters & extenders? what are the advantages & disadvantags of those? Thanks.

[John Sims]

With most extenders you seem to loose all connection with the lens so AF and aperture control seem to go down the pan.

You don't with a filter, but it is more glass to disrupt the image. The filter lenses are often cheep and not matched with the optics of your macro lens.

How small are your watches? I would have thought your 100mm Macro would have brought you in close enough.

Another option is to use an inversion ring so you use the lens back to front. You have all of the issues with the extension ring, loss of control etc, but at least you are maintaining matched optics.

[John_B]

DolphinV8,
When you say extenders are you referring to a Tele-Converter (like this one (http://www.bhphotovideo.com/bnh/controller/home;jsessionid=FwsYxLVvCF!1184335543?O=278&A=details&Q=&sku=220457&is=USA&addedTroughType=categoryNavigation)) or an extension tubes? (like this (http://www.bhphotovideo.com/bnh/controller/home;jsessionid=FwsYxLVvCF!1184335543?O=Search&A=details&Q=&sku=375102&is=REG&addedTroughType=search)) ???
If you mean extension tubes, with a full set of Kenko extension tubes you can achieve 2:1 macro (double the power then the lens without the tubes) with your 100mm f/2.8 macro lens without a loss in sharpness or quality and still have full control over your lens.
Now if you meant extender like the Canon 2x or 1.4 TC first they wont work with the Canon 100mm f/2.8 lens unless you use it with a 12mm extension tube. Second they will reduce sharpness.
I used a close up filter in film days but I would never bother with it again I would rather extension tubes any day (my personal choice) :)

[John Sims]

With most extenders you seem to loose all connection with the lens so AF and aperture control seem to go down the pan........

Damn, wrong again. I should have added:-

at least you do with the cheap ones off eBay. ;)