Not sure I fully understand the question. Are you wanting a filter for the front of lens or one for PP'ing?
How about a very thin smear of Vaseline on an old UV filter or a stretched pair of tights over the lens?
For PP, I'd go with Imagenomic's portraiture but careful not to over do it as it is generally accepted that babies need little to no smoothing.
Probably not what you were after but hopefully it will bump you to the top so someone with some experience can give you a proper answer.![]()



Well if baby cries when undressed, try getting some nice material to swaddle instead.
You will need to be very, very patient. Try undressing the baby, wrapping in a blanket tight, then when he/she is sound asleep, laying on your prop. The leave it for a bit. Once you know he/she is settled there, remove the blanket slowly. It sometimes works with a baby that isn't settling well.
If not, you'll just have to go with it, but don't get hung up on getting a certain pose. baby rules the shoot.
Allow 3 or 4 hours for the shoot.
Make sure the room is Very warm.

and don't rush it, you can take breaks to allow the baby some space so he/she does not get fed up
l do newborns a fair bit.
Lighting....natural where possible....lens wide as possible. l do use a softbox sometimes.
Props...beanbags are fab. They support well, and you can change the cover to change the look and feel.
Don't use filters....you want to get detail, but with soft skin, so it's all about post processing.
Untitled by MaddyZangles, on Flickr
IMG_0006 by MaddyZangles, on Flickr
On the images with the eyes open, are the eyes sharpened?
Rosie