Obviously you can't have two scientists talking about things they both completely understand because it would be like:

"Did you finish the--"

"Yea, just before it cut off."

"Bet that was close."

Obviously two people who are close as such know what they are talking about and don't need complete explanations with proper grammar, but readers do.

There must be other techniques than the standard smarty/idiot, though I do see that a lot.

How about a congressional hearing?

Court testimony directed at a jury?

But I think that explaining something new to someone isn't necessarily talking to an idiot. For me this holds true especially if the subject being discussed is totally out of both the character's and (perhaps most especially) the reader's field of experience.

Or it might be an exchange between a husband and wife. I am a historian, my wife is a scientist; she doesn't intuitively understand what I talk about, nor I her.

You could also switch things around. The one doing the discovery and interpreting the data is almost certainly NOT the person who will get credit for the discovery (Principal Investigators are usually too busy writing grants to work the bench). You could have the grad student or Post-Doc report to the PI what has been discovered. The PI will be quite intelligent but will also need to be filled in on details that, chances are, he/she is not familiar with.

There is also the weekly lab meeting that many scientists have to participate in. During that meeting people discuss their different projects with people who don't know a Southern Blot from a Western Blot (maybe).

Of course, you should always ask yourself if this information is even important. It can be quite tempting to give more info than the reader truly needs. At the end of the day, we know that the MD Device makes things go 'splodey and not much else.

Often, they would have to explain technical things to the Captain who, being a military type, wasn't expected to understand science, medicine etc. So he could often say "Why can't we do <something sensible sounding>?" and they would reply "Because <conversational-sounding info dump>."

Or the officers would get into trouble and in dealing with it they would have to explain the intricacies of their various disciplines to each other.

"What's that funny thing on his face, Bones?" said Scottie.

"It's a Zantazian bug which will eat him alive -- and the rest of us -- unless we do something dramatic just after the next advertizing break."

Bones and Spock were clever. In the middle of a crisis Bones would insult Spock about being unfeeling, and in response Spock would tell Bones - and us - some technical stuff.

"What, you'd leave the Alkazoids do die? You unfeeling machine-like Vulcan. You disgust me." Bones glared at Spock.

"Bones, our transporters need battery power. Our batteries are almost down to zero and we need them to fire our Phazers and repell the Klingons. So we could beam the Alkazoids up but then the Klingons would kill them as well as us. If you'll excuse me I'm on my way to get Scottie to give us more power -- for both the Phazers _and_ the transporters."

Just a thought,
Pat

"Luck, sound engineering design, and a little knowledge. Good design, ten times that much luck, and a precious little kowledge. It was luck that had placed the Ship near a star with a planetary system..."

And so on, for a couple of pages of pure exposition, stuff no character in the story knows.

When you know the rules, sometimes you can break the rules.

Basically, discribe the item, then show it in use. If it is something unusual, you might have the person checking it over to make sure all the settings are right and everything tightened. You then mix in the info dump with his activities.

My issue was from a hard SF point of view. I suppose I should read some HSF and see from examples, but sometimes the classics break rules that a newbie can't.

Clever indeed.

Now layer it. Does either have something at stake other than the surface argument? The new kid wants to prove himself? The older character wants to show he's still keeping up? The Skittlinbert from Omega 9 advocates technology native to his struggling world?

http://www.writing-world.com/sf/infodump.shtml

"I will come to conduct you to the king's presence when the fifth hour is told." ...

Alder...wondered what the man meant.

He learned, presently, that here in Havnor four trumpeters went out on the high balcony from which rose the highest tower of the palace, the one that was topped with the slender steel blade of the hero's sword, and at the fourth and fifth hours before noon, and at noon, and at the first, second, and third hours after noon they blew their trumpets one to the west, one to the north, one to the east, one to the south. ... A boy he met walking in the gardens explained all this, a small, thin boy in a tunic that was too long for him. ... The boy was called Rody and he had come with his father...and he went to school in the palace, and he was nine, and he missed his mother and his sister."