I had to dig back to 2019 to find this pic, but this is how I did it back when I grew photoperiod plants. I had the two 4" ducts stuffed into the 6" sock on the side of the tent, and the S turn kept the light out, but it was nearly impossible for me to move enough air to keep the humidity in check this way.
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That’s when I came to the conclusion open up the bottom vent opposite of the exhaust fan . 
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My 2 1/2 x 5 tent is squeezed in it’s space with 4" clearance on the side in the picture, no clearance in the rear, and no clearance on the other side, lol.
It works perfectly now with the 6" sock open and green filter over it. It’s amazing how big of an effect the ducting with bends has on CFM’s.
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@TLC if you look up a few comments in this thread they said that was insufficient still.
@Cap_Ron
When I first started this plant I was in a 2x2. Then I bought this 2x4 I moved the plant into the 2x4. And started a new seed in the 2x2
Thats why it’s the only plant in the 2x4 atm.
When I was veging this plant I had just got the exhaust fan. And it was still end of march beging of aprilm so the humidity wasn’t as bad. My humidity kept dropping in veg to 45. I read somewhere that bends restrict the flow. So I made the pipe longer and put a few bends in it. It helped keep my humidity a little higher.
Now I’m in flower and I need that 45 humidity the exhaust doesn’t do it 
Go figure lol.
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This is cited from AC Infinity:
“The sharper the bend, the harsher the efficiency reduction; a 30° bend cuts the amount of airflow by 20% while a 90° bend diminishes airflow by 60%!”
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@BassNBricks, a few things to keep in mind. The goal of 45% humidity would be nice and safe, no doubt, but it’s incredibly difficult to achieve in a lot of circumstances, and not necessary. If you can’t meet that goal, there are ways to help mitigate the risk of pathogens, and that’s the only reason a humidity level that low is recommended. It’s not that the plants want a low humidity level during flowering, it’s just to keep the risk low. The plants would be happy with a humidity in the low 50% range, and as long as you keep air moving really well between the exhaust and basic fans for circulation you’ll be fine. I’ve had my humidity spike on me several times over the years and it’s been up in the mid 60’s a few times during late flower. Of course I’ve done everything I can to avoid that, but I’ve never had any big problems as a result of it.
I was in a very similar situation to you a few years ago. I upgraded from a 3 x 3 to my 4 x 6 closet, and I tried to make my existing equipment work in the bigger space. It just wasn’t sufficient, so as I could afford to, I upgraded piece by piece.
For now, the key is just to make sure you keep the air circulating well, and I think you’ll do fine.
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I wish that the Jardin flange & light trap setups were more affordable. They are compact & work well as light traps. They also have a cloth filter element inside that can be removed for cleaning if you split the thing apart. But to maintain max flow, most exhaust fans are going to need at least a few of them in the tent. I estimated that my Vivosun 4" which flows only around 200cfm at full power with no obstructions would need to see two or three of those 6" Jardin light traps before they would flow enough intake air for the fan to not lose any flow at max power. They are like $30 each. Something like my Vortex 4" might need to see twice as many.
But in any case one thing to keep in mind is to give the fan enough intake area to maintain max flow at 100% power.
It’s not too hard to get a basic idea of how much intake area you need. One way is to briefly seal up all intakes, run the exhaust fan at 100% power, then start opening the door until you lose suction. Measure the area of the opening, & that is about how much intake area you need to provide. Also you can spread the intake area around, it can be a few different holes in different areas, if that is easier to implement. If you install light traps, you might need to increase the intake holes, since light traps usually steal flow. Unless you make them big enough not to.
Also if you do all of that but you’re still running a very restrictive carbon filter, & then later decide to upgrade to a more free-flowing one, you’d probably need to add more intake area again to allow for more flow.
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Switching to lights out during the day. Helped to stabilize my humidity as well
As you can tell I did it around Thursday the 15tg
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I was at Lowes yesterday picking something to string another light. While I was there I checked out the plumbing section. Apparently that’s where all the filter stuff is. I picked this up. It was the darkest one there. I didn’t see any of that green stuff. I’m gonna give it a shot tonight. It lets some light through. But I have another tent next to it. And a dresser on the other side. Soo I’m hoping it’s dar enough.
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So while dark what is exhaust fan set at. If on a higher setting have u tried leaving the fan on high setting exhausting more while lights r on when lights go out set it to just pull enough air out of the room but it still stay a touch warmer from not exhausting fast. Warmer air less humidity atleast here it works this way. Lights on u have to blast the fan lights out I cut speed down to a 1 or 2 and it seems to keep my the in check way better if I crank fan at lights out it always raises rh massively while exhausting at a faster rate
