Awesome, thanks again.
If I do get the Sigma 50, which I probably will, any reason to NOT add in the 30 as well? Or just a waste of money? For some reason I've got this thoughts in my head that I should go with the 30 instead because it'll give me 45mm were as the 50 will give me 75mm actual. The reason I think I have this thought in my head is because I like to random "spur of the moment" pics when with my friends and at other social gatherings, and I want the be able to quickly take the pics without having to step back a few feet. Or is there a better lens for this scenario?
I hear the 30mm 1.4 is a pretty good performer aswell which is nice for general photography, I have the Nikon 35 1.8G but I still fail to really fall in love with it and often consider selling it. It's sharp as hell and has great contrast but seems to be lacking in a few other departments that actually matter to me. The Sigma 30 1.4 has much nicer bokeh than the 35 1.8G from what I have seen so it would work well as a general lens, the Nikon is sharper though but then again sharpness is not the be all and end all. But the problem with these lenses is they still behave like wide angle lenses in effect, for subject isolation in people photography they are nowhere near as effective as a 50mm lens is.
But talking from personal experience again, last year I photographed a whole party for a friend using mainly the Sigma 50 1.4 and nothing else. I just found the results it gives are that good, that taking a few steps back is no big issue! If you were looking to take landscapes or street scenes, then I would suggest the 30mm. But as you are looking to do people shots, I think the Sigma 50 is the perfect choice and to be honest 75mm is not that long.
Just one other thing to remember if you didn't know, if you are taking people shots. You do not really want to go below 50mm unless you are doing full body shots, if you take headshots with a 30mm it will give you great distortion meaning the nose will be too big and the ears too small. The 30mm may become effectively a 45mm lens, but it is still a 30mm wide angle lens, it would still be useful for people shots at gatherings but you would always have to be careful not to get too close to the person, otherwise you will get the unflattering distorted face look. Crop factor has no bearing on the focal length of the lens.. hope this makes sense.
What you are describing is perspective, and it has alot more to do with distance from the subject than simply the focal length. if you want to fill the frame with someone at 35, than sure you will have slightly elongated features, but if you move a little further back the features will appear the same, for example a head shot from the 50 1.4 will look better than the exact same shot with the 35, but move a little back perhaps go waist up and it looks the same. Also yes subject isolation is cool and we all love shallow dof but you only need that when the background is distracting, having all the portraits shot at 1.4 gets boring fast and you cannot incorporate the general scenery as much. If you truly want isolation the 85 1.8 does a better job than the 50 1.4.
If your telling me that you cannot use wide angle to shoot portraits than something is wrong, watch joe macnally and chase jarvis work, they shoot portraits often with the unmistakably obvious bulbous front end of the 14-24 2.8. They incorporate the area surrounding their subjects and it makes for a much better picture than a "bokehlicious" general photo studio head shot.
This is why i recommend getting just the 18-55 and learn to see what you like, dont just read a review and go, "hmm everyone says this is what the 35 is good for and this is what the 50 is good for, so i am gonna go with the 35!" 35 and 50 aren't that far apart, most people and photographers would not notice the difference between the two in a picture, what they do notice is the barrel distortion. Just run the distortion correction in light room and you are all good!