It's actually K-AH-R-N-Z, although Columbo's accent might make it sound more like K-AH-NZ. But either way, in English it would definitely not sound like your second option, with the ES as a separate syllable.

Regional accents are beginning to disappear in America, as we all adapt to the sounds of national broadcasters, but "Columbo" is from a time when it made a big difference (and actually it still makes a difference) which part of the country you are from. I hope this helps.

Well in japanese, it could be pronunced like this by a japanese person:

けるぬず KE - Ru - Nu - Zu => but without pronuncing the "U"s => [KERNZ].

But that's right, in some original US versions I had, Columbo has a very chewy accent (sort of "texan" accent), which is quite particular.

Ted-san and Noorvensen-san,

Thank you very much for your comments.

I understand that Karnes should be pronounced "K-AH-R-N-Z."

＊ カー(Kah)・ン(nn)・ズ(Zu or Z)

ロバート・カーンズ (RO BAA TO + KAH NN ZU)

It's always difficult to put an English name in KATAKANA Japanese, is it ? For example, Patrick McGoohan in Katakana Japanese is like: パトリック・マクグーハン (Pa To Rit Ku, Ma Ku Guu Hann)....

Well, again thank you very much for your kindness, both of you.

Yours
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I'd say it's rather like this :

ロバート・ケーンズ, with KE (not KA) because in english, "a" is pronunced [EI].

Thank you very much again.

I have attached a YouTube like below, which pronounces "Carnes (though not Karnes)."
http://www.youtube.com/watch?v=wQTDQ9mj8Gw

Could you tell me if this sounds right or similar to what you suggest ?

I believe it does not make any difference if the name begins with "K" or "C."

Yours,
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