Most opera companies in this country these days boast young-artist programs. But the Washington area is distinctive in having two whole summer festivals dedicated to young professional singers, and both of them opened this weekend. On Friday, the Wolf Trap Opera offered “Giulio Cesare in Egitto” (“Julius Caesar in Egypt”), perhaps Handel’s best-known opera; Castleton followed with Puccini’s “Madama Butterfly” on Saturday night.

One was uneven. The other was — uneven. In the difference between the unevennesses lies the tale of two distinct approaches to young-artist training.

The Wolf Trap Opera has been in operation for 43 years. It offers a sturdy program with a good track record of picking out promising singers — such as Eric Owens, the bass-baritone who sang for two years at Wolf Trap in the 1990s and returned this summer, in the midst of a major career, as Wolf Trap’s artist in residence. Kim Witman, the program’s director, selects the operas to be performed each summer — including, this year, “Carmen” at the Filene Center on July 25 — after conducting an exhaustive audition tour around the country and identifying singers she’d like to work with. Instead of trying to shove voices into a particular repertory, she tries to find repertory to fit particular voices.

This year, she found a crop of countertenors — including John Holiday as a sweet-voiced and physically imposing Caesar with clean, crisp coloratura. He was matched in vocal beauty, if not in precision of baroque ornaments (the various embellishments singers in this period gave to their music) by the lyrical soprano Ying Fang, who was heard last year here in “Il viaggio a Reims” and this summer dazzled as a fashion-plate Cleopatra.

In director Chas Rader-Shieber, the company engaged a prolific veteran with a certain kind of tongue-in-cheek slickness that he’s applied to many operas, and Handel operas in particular. Here, as before, he offered a funny, sugary, aggressively clever take on an old story. He gave a 1950s cast to ancient Egypt with a postcard-like backdrop of pyramids (sets: Judy Gailen), a trio of French maids in short shirts puffed out with crinoline and Egyptian-style bob cuts with beads flanking their faces (costumes: Paul Carey, with Anne Nesmith designing hair and makeup), and the leader of the Romans in a blinding white military uniform — all given extra immediacy in the intimate setting of the Wolf Trap Barns.

The point is to show audiences that Handel doesn’t have to be scary, despite the fact that his operas basically consist of long strings of arias in ABA form, sung one after the other. This goal was furthered at Wolf Trap by aggressive cuts that strip the opera down to a playing time of about three hours. This meant eliminating some arias and chopping the B sections off a couple of others, but it also spared the audience from having to sit through four hours of performance. The spirited conducting of Antony Walker, the popular music director of the Washington Concert Opera, helped move things along, though the small pit and the consequent overflow of instruments into the auditorium seemed to challenge his usually crisp ensemble abilities.

But not all the singers were at the same high level as the two leads, in part because they tended to offer the heightened dramatic sensibility of 19th-century opera rather than the musical clarity and precision called for by early 18th-century works. Renée Rapier offered a thickened mezzo sound as Cornelia, who is confronted with the severed head of her husband, Pompey, early in the proceedings and, in this production, subsequently attempted suicide a couple of times with various garden implements; Carolyn Sproule sang brightly and occasionally harshly as her son Sesto, whose emotion at his father’s death sometimes carried the singer right off the right pitches.

As Achilla, Jeongcheol Cha was the epitome of the term “raw talent,” singing with a big, rugged, dark baritone and almost no polish. Two small roles, Curio and Nireno, were admirably filled by Alex Rosen and Kara Sainz, members of the Wolf Trap Opera Studio.

Eric Jurenas was the second countertenor — adequate, but not making a strong vocal impression in the oily, villainous role of Ptolemy. (There’s a final performance of the opera Tuesday night.)

Castleton’s learning curve

The Castleton Festival was founded in 2008 by star conductor Lorin Maazel at his home in Virginia’s Rappahannock County. It’s expanded rapidly, from Britten chamber operas to full-blown Puccini played in a permanent tent-like structure on the property with a full-size orchestra pit. Every year it has offered something slightly different, but the theme remains the same: The festival is a training ground for singers, instrumentalists and conductors, most of them drawn by the lure of working with Maazel.

The question of how far this festival rises and falls on one man’s involvement is being put to the test this summer. Maazel has come down with what appears to be a fatigue-related condition from extreme overwork, and he canceled virtually all of his appearances for the coming season , including resigning his directorship of the Munich Philharmonic. Castleton, of course, is home, and this summer Maazel has been attending rehearsals, working with participants, and was said to be planning to conduct Saturday’s “Butterfly.” But the frail impression he made when he walked out to address the audience before the show — supporting himself against the wall and hanging onto the mike stand — did not inspire confidence that he will indeed be conducting soon, though the festival’s director, Nancy Gustafson, said it could happen any day.

Opening night of “Butterfly,” in any case, was in the hands of assistant conductor Brad Moore, an accompanist and conductor, and though the orchestra sounded richer and fuller than the norm, it offered only a shadow of the power and precision that Maazel brings to the table.

Castleton has pulled rabbits out of a hat before in the singing department — notably with Joyce El-Khoury’s achingly lovely “Suor Angelica,” jumping in for an ailing colleague on opening night 2010. In “La fanciulla del West” last summer , soprano Ekaterina Metlova just about pulled off Minnie, in part through a dramatic affinity with the role. Saturday night, however, she seemed at sea as Cio-Cio San, starting out shaky and uncertain, singing with an acidic tone and no warmth or roundness in the voice, and more going through the dramatic motions than actually incorporating the role of an innocent 15-year-old girl losing her heart to a man who ostensibly marries her but has no idea of actually remaining her husband.

Jonathan Burton, another Castleton regular, was sometimes constrained but genuinely ardent as Pinkerton; Kate Allen was a strong Suzuki; and Corey Crider was a firm, warm Sharpless (his real-life daughter, Grier, played Butterfly’s child). But the director, Tomer Zvulun, who did such nice work in Wolf Trap’s “Falstaff” last summer and “Don Giovanni” the year before, inexplicably failed to create here a production that cohered.

Erhard Rom’s sets featured the single sliding screen across the stage that has become a near-cliche of contemporary “Butterflies” (including the one seen at WNO in 2011), which alternately acted as a screen for projections or parted to reveal them. Butterfly’s initial entrance, one of the great moments of musical and theatrical magic in opera, was here on a community-theater level no more than a bunch of women carrying parasols. For the love duet, she and Pinkerton stood locked in an unconvincing embrace while video footage of crashing waves broke behind them — only to ebb as soon as the singing stopped. There were some good ideas, including casting Yamadori, Butterfly’s would-be suitor, as a young and handsome hunk (a bit hard-to-hear Aaron Wardell). But there wasn’t enough to create an illusion, or help Metlova compensate for her weak singing by finding her dramatic footing.

There are three more “Butterfly” performances, on July 6 and 11, with this cast, and with an alternate set of leads on July 20. It remains uncertain whether Maazel will conduct any of them, and what kind of difference it will make if he does. In the meantime, the festival continues with orchestral concerts, well-known soloists (James Galway! Alisa Weilerstein!), children’s events, cooking classes and a production of “Don Giovanni” that opens Saturday with or without Maazel in the pit. Castleton’s learning curve continues — for its participants and for itself.

The Wolf Trap Opera season continues through a double bill of “Le pauvre matelot” and “Les mamelles de Tirésias” on Aug. 8, 10 and 16. The Castleton Festival continues through July 20: see www.castletonfestival.
. For more on other summer opera festivals, watch for a three-part series that started this weekend in the Sunday Arts section of The Washington Post with a piece about the Opera Theater of St. Louis .