The reigning RaboDirect PRO12 champions scored two tries against the French side, Kahn Fotouali'i and Ryan Bevington crossing in either half.
But the four-time kings of Europe had too much class for the Welsh region, racking up five tries for the bonus point through Florian Fritz, Yannick Nyanga, Vincent Clerc, Census Johnston and Yoann Huget.
But Humphreys, whose side had six players making their Heineken Cup debut, took a lot of positives from the youngsters' brave display.
"We're very proud of the boys," he said.
"We could have improved on a few things tactically but we could not have improved the effort - that was as good as it gets.
"We had six guys making their Heineken Cup debut and I thought they were outstanding.
"With the amount of set-pieces they had in our half you would have expected the score to have been heavy, but in the end I don't think it did us justice.
"We are disappointed because coming in at 12-7 at half-time we should have been in front. We created a lot of pressure and they were ragged.
"In the second half we wanted to get down their end and create some set-piece pressure but we weren't able to do that.
"We felt we could have a real crack and if we could have just executed better a few times it could have been a different story."
Scarlets also went down to defeat in the Heineken Cup on Saturday as Exeter Chiefs beat them 22-16 at Parc y Scarlets.
And there was more bad news for Simon Easterby's side as fly-half Rhys Priestland limped off with potential Achilles damage, much to the head coach's displeasure.
"You can't give any side the start they had and we slipped off a couple of tackles and they scored a soft try and they scored a couple of points from our error and indiscipline," he added.
"The second half was much better. We played a lot more tempo and we won the second half 10-6.
"When you give a side the start we did it was always going to be difficult to get back into the game."
"Rhys has an Achilles injury which we won't know the extent of that until he has had a scan. But it did not look good. It was one of those injuries that are going to happen and there is nothing you can do about it."
There was some good news for the Welsh regions however as Dragons saw off Mogliano 33-0.
No.8 Ieuan Jones went over twice in their bonus-point Amlin Challenge Cup win, centre Andy Tuilagi, Will Harries and Tom Prydie also crossing for Darren Edwards' side.
63x46.png){kind=logo}