There is no explanation in the change of uniforms after Sisko boards Deep Space 9. We see Chief O'Brien in the newer uniform (division color on the shoulder with the gray under tunic) while Sisko remains in the TNG style uniform. Later, Sisko appears in the newer uniform while Dax and Beshir arrive in the TNG style uniform.
None of the Enterprise crew are shown in the newer uniforms and even Chief O'Brian is in a TNG style uniform when he revisits the Enterprise and is later transported back to DS9.
There are a few theories as to the difference of the uniforms. 1) there were uniforms for starship crew and non-starship crew or 2) a new uniform design was created and Starfleet members were allowed to wear whichever uniform they chose.
The same issue would occurs during the motion picture "Star Trek: Generations" (1994) which would air a year later where the crew would alternate between the two different style uniforms.
Another change to the inform is the shade of blue on the science uniforms. The TNG style was blue while the newer style was a teal blue. There is a discernible difference in this style to what was used on Voyager. On Voyager, the tunic laid flat where as this style used on DS9 would stick out towards the top where it met the gray under shirt. There are also variations in the color of the under tunic. Sometimes it was gray, sometimes it would appear a light purple. Grey would be the color used on Voyager.
None of the Enterprise crew are shown in the newer uniforms and even Chief O'Brian is in a TNG style uniform when he revisits the Enterprise and is later transported back to DS9.
There are a few theories as to the difference of the uniforms. 1) there were uniforms for starship crew and non-starship crew or 2) a new uniform design was created and Starfleet members were allowed to wear whichever uniform they chose.
The same issue would occurs during the motion picture "Star Trek: Generations" (1994) which would air a year later where the crew would alternate between the two different style uniforms.
Another change to the inform is the shade of blue on the science uniforms. The TNG style was blue while the newer style was a teal blue. There is a discernible difference in this style to what was used on Voyager. On Voyager, the tunic laid flat where as this style used on DS9 would stick out towards the top where it met the gray under shirt. There are also variations in the color of the under tunic. Sometimes it was gray, sometimes it would appear a light purple. Grey would be the color used on Voyager.
When Sisko is talking to Jennifer on the beach he says that his father "was" a gourmet chef. In later episodes his father still is a gourmet chef.
The opening crawl states that Captain Picard was kidnapped by the Borg on Stardate 43997, and the Battle of Wolf 359 takes place several days later. The time skips to Stardate 46379, which is supposedly three years later. 1,000 stardates is equal to a year, which makes it about two years and four months later, not three years.
After Capt. Sisko and Jake arrive at DS9, as he is showing Sisko around, the stain (some sort of dust or powder?) on O'Brien's tunic changes size a few times.
In some closeups, Major Kira's Bajoran makeup includes ridges above her eyebrows, similar to the makeup used for Ensign Ro and other early examples of Bajorans on TNG. In most shots, the ridges are missing, limiting the makeup effect to just the bumps along the bridge of her nose, which is how Bajorans will be presented going forward.
When Sisko and Dax cross into the Gamma Quadrant for the first time, the computer incorrectly identifies the nearest star system as a ternary system. It says that the star system is comprised of twin O-type companions. A ternary (also called trinary) system would have three stars in it, as this one only has two it would be called a binary star system. Also it seems highly unlikely that Sisko and Dax would know this system from memory, it's a obscure, uninhabited star system over 70,000 light-years from Federation space and has only been scanned by long range sensor probes, yet some how they both know off the top of their heads where this star system is.
The opening text crawl spells the name of the Enterprise's captain as "Jean Luc Picard." His name is properly rendered with a hyphenated first name, Jean-Luc Picard.
The artifact given the Sisko by the Kai is referred to as an Orb of the Prophets. Orbs are, by definition, spherical. The artifact seen on screen is bulbous on either end and tapered in the center.
Dax's spots are not on her face and neck in all scenes. When arriving at the station, there are no spots. The spots are present in her flashback. When going through the worm hole, her spots disappear again.
Dax's spots are present in all scenes, but can sometimes be difficult to make out due to lighting and the film quality of a TV series edited on videotape in the early-to-mid 1990s.
Dax's spots are present in all scenes, but can sometimes be difficult to make out due to lighting and the film quality of a TV series edited on videotape in the early-to-mid 1990s.
O'Brien, who is not a commissioned officer, is called "sir" by the transporter room ensign, who outranks him. Authority in Starfleet is affected by assignment. As O'Brien holds a position of authority (chief of transporter operations aboard the Enterprise and chief of engineering aboard DS9) over the ensign, the ensign addressing him as "sir" is quite proper.
Female military officers take offense when referred to as "sir". "Ma'am" is the proper form of address.
This may be true in current time, but starting in TNG, all officers, including females, are addressed as "Sir".
During the attack, a supposedly solid fallen girder or column on the Promenade is seen to bend like foam when someone lands on it.
The TNG style uniform that Jadzia wears when arriving on DS9 is very ill-fitting, most evident by how the black shoulder yoke, which should be straight across, is stretched and sloping. Clearly the producers did not wish to spend money on creating new uniforms (which reportedly cost around $3000 each) for the cast for just a scene or two and reused costumes from TNG and a proper fitting one could not be found for Terry Farrell.
The scale of the Danube-class runabouts is off in several shots, often appearing much larger in comparison to the station and other ships than it should. The Danube-class ship is only about 23 meters long, while the Cardassian Galor-class ship is 480 meters. The Cardassian ship should be more than 20 times the size of the runabout, yet the runabout is shown nearly half the length of the Cardassian ship.
As a follower of the Prophets it is unlikely that Kira would refer to the station as "godforsaken".
The "Prophets", when speaking to each other, say "The creature must be destroyed before it destroys us", and "Destroy it now" when referring to Sisko, but the words "before" and "now" describe concepts of linear time, which the "Prophets" do not understand.
During his conversation with Jennifer, during Sisko's first orb experience, Sisko says his father WAS a gourmet chef. Later in the series, we find out that not only is his father still very much alive, but he is STILL a chef running his own restaurant in New Orleans.
Odo is a shape-shifter, but has a certain mass. When he shape-shifts into the bag to get aboard the Cardassian ship he should still weigh what he does when in his humanoid form.
The Cardassians are supposedly jamming all subspace frequencies to prevent DS9 from sending a distress call to the Enterprise, yet they are able to send a message to the Cardassian 4th Order Fleet for reinforcements.
When the second Runabout is heading to the wormhole, Dax states that they'll be at its position in 2 minutes. The wormhole then immediately opens up directly in front of them.
The first time Picard says Bajor, he pronounces it Buh-jor, with the accent on the second syllable. Later, he pronounces it correctly as Bay-jor, with the accent on the first syllable.
During Sisko's flashback to when he met Jennifer, he offers her a lemonade and she says that she doesn't 'expect' drinks from strange men. She should have said 'accept' drinks. The DVD captioning shows that she says 'accept.'
During the battle of Wolf 359, the Saratoga's Captain clearly says "Recalibrate shield mutation," instead of "modulation."
Sisko balks at the idea of Jadzia becoming romantically involved with Dr. Bashir, as the Dax symbiote is several centuries older than he is despite Jadzia being roughly the same age. In Trill culture, it is expected that hosts seek out new experiences and relationships, and there are even rules against re-association with former hosts' partners. Expecting that Jadzia only fraternize with individuals as old as the Dax symbiote would severely limit her social and romantic prospects in ways that run counter to her culture.