is it advisable to use pop filters to avoid blows for recording vocals? or should we place the mic a bit off from the mouth though it might lead to loss of high frequencies since they are directional? also could anyone please tell me if there is a downside of using pop filters and how do we get rid of lip sounds?
Ideally while recording vocals you would want to avoid the proximity effect ie. Artificial Low frequency generation caused if the microphone is placed to close. A Vocal recording should be between the bandwidth of 900 Hz to 4 Khz. To achieve this you should have your mic placed at least 1 foot away from your vocalist. You wil achieve the desired level of sound from this distance but there is still a question of the pop sounds created by the lip movements. For this you should place your mic either 15 degrees to the left or right of the source of sound. If not that then you should place your microphone 25 degrees to the top with your diaphragm still pointing to the source of sound.
In this way you can avoid using your pop filter while achieving good levels and proper frequency response from your vocals. From the distance of 1 foot you would not loose any high frequencies and you will cut down on your Proximity without using your pop filter.
A pop screen has more uses than just reducing pops and wind: it also protects the mic from moisture from someone's breath, and it can serve as a spacer ensuring a minimal distance from the mic is kept which you can set by adjusting the distance between the pop screen and the mic. This can be handy to control the amount of proximity effect.
Pop filters won't significantly reduce any frequencies (unless you're spacing it far enough from the capsule). You're going to be using eq anyway right? Compensate here.
There are a lot of ways to reduce lip noise (i assume you mean ticks) like apples, limes, water etc but ultimately you may need to clean up the waveform after recording. You can do this after a good take if you're quick enough!
Ultimately the proper use of a pop filter will only help you.
Besides reducing pops and wind, my secondary purpose for the pop filter is to get my talents to a safe distance away from my mic. You won't believe how many VO artists love kissing microphones, and inadvertently dumping a gallon of spit into it. Can't stand a stinky mic.
That being said, if you have amatures going in front of the mics, they may be a little intimidated by the mic, and they will usually assume the pop filter to be the mic and naturally back away from it.
Minus giving our talents water, apple jiuce, honey, etc, it's really up to how conscious they are of their own mouth sounds. Getting a good VO artist usually helps you to avoid a lot of these problems. Otherwise you will just have to edit them out.
Most inexperienced talents will end up getting closer to the mic than what you intended. This is probably due to the psychoacoustic impression that louder is perceived as better ( if you have never heard before about the "equal-loudess contours" I promise you an amassing bit of reading and some information that will be invaluable for your sound work)
Using the screen will avoid the talent getting closer than what you want. In the states i think they also use guns :)
If possible; try and use an Omnidirectional microphone (like the Schoeps MK 5 switched to omin) together witch your other mic. The effort you have to put in it is making the vocal booth a lot more silent and dry. But you end up with the great opportunity of using the beautiful low frequencies of you omni (omnis are not sensitive for the proximity effect) in your (pre)mix. And don't ever record with a directional mic without pop filters. The frequency-loss you'll find is practically inaudible (when using a good one like the Rycote stuff) and you're simply not safe of having a good recording if you don't use it.