VPD is a sound way to create the optimal temperature and RH combination for your plants. You can spend a lot of time and money optimizing VPD. I'm more than happy to share (at great length) how to do that.
Cannabis will grow, very well, in temperatures of about 80° (up to 85 in veg and early flower) and with an RH of 60± in veg and 50± in flower. I've spent a lot of time (many hundreds of hours) learning about what makes an optimal grow environment for cannabis and VPD isn't that big an issue in terms of crop yield, in most grow environments. If you're growing in areas that have climate extremes, it can be a total bitch but other than those areas, a good rule of thumb is that if it's comfortable for the human, it's OK for the plant.
I'd recommend that, while you're planning on how to influence VPD (it can be very hard to control VPD), you spend $32 on a Uni-T lux meter and get your plants as much light as they can toleratate.
I urge that because what is undeniably a big issue in how well a plant grows is how much light your plant gets. My recommendation is to get the Uni-T and increase light levels on your plant until they hit their "light saturation point". The LSP for cannabis is roughly speaking, 800-1000µmol, and using a light meter will help you get that amount of light on your plants. Once you set your lights so that they have, say, 800µmol, you need to watch your plants and see how they react. If they handle that amount of light well, turn up the dimmer until they're at 900. If the leaves start to "taco" or "turn away from the light", drop the PPFD by 50µmol. By cycling through that, you'll ensure that your plants are well fed — the only way plants get food is when they use light and CO2 to generate sugars (glucose) via photosynthesis. If they don't get "lotsa light" you won't get lotsa weed.
As plants grow, they'll get closer to the light and that means they'll be getting more light so you need to see how they handle the increased light level. A lux meter can tell you about how much light they're getting but only the plants can tell you how much light they can deal with. If you keep a grow journal, you can use the light meter settings for your next grow.
Assuming that you have RH and temp at roughly the values that have been mentioned cannabis will grow well. If you raise your light levels, your plants will grow incredibly well.
Re. VPD — I glommed on to VPD when I started growing in early 2021 and I'm on my third generation of equipment. I use the word "influence" VPD rather than "control" because the only way to "control" VPD is if you can control temperature and RH in the tent. That's not easy because you have lights that generate a lot of heat, a driver for the light that generates some heat, and you have plants that are constantly putting moisture in the air. And, if you're in soil, you've got evaporation of moisture out of the soil to add to the RH in the tent.
It's a complex, dynamic environment.
The nice thing about dealing with lights is that it doesn't change that much. Even if your plants grow 1" a day, you can compensate for that by raising the light 1". In contrast, temperature in your grow environment will change over the course of the day, due to the heat generated by the grow light as well as change in the temperature outside the tent. And then there's the RH change in the ambient air as well as the change in RH over the course of the day and then again when temps fall during lights out.
You can nail VPD and get a marginal increase in crop yield and quality. I'd recommend that you start with getting lotsa light on your plants, which is easier to do and has a significant, direct impact on crop yield and quality, and then go for the marginal improvement why nailing down VPD.
AC Infinity lights present challenges to the grower because they have a hot spot in the center. If you use a meter, it will be easier to optimize your grow. I enjoy a challenge but no way would I try using their lights without a meter.
