Bothering birds' nests, with whatever good intentions you have, is not a good idea. It can cause the youngsters to prematurely leave the nest and get into trouble.

I have read (Noel and Helen Snyder's research, and others) that some hawks will abandon their nests if people bother them. So that's another good reason to keep a good distance from them.

There are time frames which raptors will allow you to vist there nest. If they are on eggs they might abandon them but once the chicks hatch its a diffent story they will not abandon them. Bird banders can climb the tree band the birds and the parents will still come back. As for chicks bailing out the nest it can happen if the eyass's are too old but when they are younger they will sit tight.

How can you know if the chicks are "too old" to tolerate being harassed by you but too young to leave the nest?

Leave nesting birds alone, for their sakes.

Please...goshawks are very secretive and protective. The stories you've heard/read are accurate -nesting goshawks are viscious and their talons are extremely dangerous. I watch 2 pair in CT and though I've birded for 30 years, would not go anywhere near their territory during breeding season for two reasons: my own physical safety, and the safety of the nest. (I accidently happened into the outskirts of a goshawk nesting territory once and was pinned down under a tree for a long time before I could get out of there safely. I was nowhere near a nest! But the parents did not want me in that area of the woods, and it was a very large area that they defended - they actually came out to the trail to warn off hikers).
Perhaps MOST IMPORTANT, it's not healthy to enter the nesting territory of ANY nesting bird, including raptors. When human scent is brought into a nesting territory, predators follow and can destroy a nest within a few hours. I've sadly seen this happen with great horned owlets when well-intentioned people just wanted to get a little closer to photograph the nest. Those well-intentioned people ended up ruining a perfect nest site with 2 small owlets, and I lost 2 months of time I'd invested watching them safely from 1/2 mile away - very sad and frustrating.
Suggestion - invest in a very good spotting scope and watch raptors in non-breeding season (late summer thru early Fall - leave them alone from December on) from a distance of at LEAST 1/4 - 1/2 mile. You can see perfect detail at those distances without disturbing the raptors. (And they WILL see you and get restless if you get closer). Same for photos-use a 400 or greater digital lens and then blow up the photos. Watch for conifer treelines/outcroppings in deep woods late afternoon to sunset. Goshawks will gently glide across the sky into their roost area like a quiet gray ghost.
The bird's activity, its habitat, etc are much more enchanting to watch daily from a safe distance. You will be rewarded greatly and the raptors will be safe and remain nesting in their preferred territories.

I did have a goshawk fly at my head once, but it was in the Fall not spring. I was on Hawk Ridge, Duluth Minnesota, one October watching migrating hawks. I was with my brother watching hawks through my binoculars, when all of a sudden I sensed some thing behind me. I turned around and there was a goshawk flying at my head. I through up my arms and the goshawk veered away from me.

Richard

Speaking of Minnesota, I remember reading over the summer that over in St Paul there was a peregrine falcon protecting its nest and attacking people walking by on the sidewalk. They had to close the sidewalk for a time until things calmed down with that bird.