How does iPhoto Save photos from multiple Cameras

Question

I have had a Mac for about 18 months. I have a Canon Digital Elph 410. Because I had only photos from this one camera I never have worried about naming. So all my photos are sequentially numbered IMG_0031, IMG_0032 etc. This last weekend, for a big trip, I purchased a Panasonic with a zoom lens. I also have on order a replacement for my Elph, a Canon SD630.
How will iPhoto distinguish between the similarly numbered photos from different cameras? The Panasonic may have a different numbering scheme, but the newer Elph is likely to come up with identical numbers as my old Elph. I know enough that when iPhoto asks me to replace I will say no. But how will I get the newer photos of the same serial number onto my iMac without erasing the old photos? Does iPhoto have a way---opaque to the user---of distinguishing between these two sets of photos based on the day they were shot?
Thanks.
iMac   Mac OS X (10.4.7)   Mac Novice

Answer 1

Importing shouldn't be a problem, iPhoto will figure it out and nothing will get deleted.
You can have multiple files with the same "title" in iPhoto. The title is what you see in iPhoto, not the actual filename of the file stored on the disk, though the two are usually identical upon import.
For iPhoto5, it works like this:
1) If two different photos with the same name and date are imported, the second gets a "_1" appended to its filename on the disk but the titles you see in iPhoto will still be identical to the original filename.
2) If two photos with the same name but different dates are imported, they are stored in different folders in the iPhoto database so no "_1" is appended and, again, the titles you see in iPhoto will be the same.
3) If the photos are identical, a dialog box will pop up to ask you what to do. You can apparently import the same photo more than once.
iPhoto6 has a different directory structure on the disk so (2) may not apply. In any case, there shoudn't be a problem.