Nifty Fifty Focusing

[Ilyanep]

So this guy I know is selling me his almost new 50 mm f/1.8 Nikkor lens for a bit cheaper than new, because the one he got isn't an AF-S so he can't auto-focus on his D40, but it works for me, because I have a D50. I'm extremely excited

So he let me have it for a bit so I can play with it, and it's extremely awesome! I can take photos in low-light situations where I would never dream of taking photos hand-held. And it gives me some nice bokeh to boot.

The only problem I seem to be having is that with such a small focal range at f/1.8, I have trouble actually getting the focus on the right part of the picture. Does anyone have any nice tricks or ways to improve at doing this?

Thanks

[lakeith79]

Jealous. If I could find a buyer for my d40/kit I would buy a new camera just for the options of having more autofocusing lenses.

As a newbie who's only taking pictures as a hobby, the AF-S lens is cost prohibitve. Maybe I'll donate blood and buy it that way

Congrats on the new glass.

[OsmosisStudios]

Depending on where your subject is in relation to you, it can be VERY difficult. Is there any particular reason youre shooting at f/1.8? The lens is a bit soft at the point: it sharpens up dramatically by f/2 and even more so by f/2.8. I tend to shoot around this point more.

Getting focus right can be VERY tough: i use the focus/recompose method and havent had any problems. That being said, I have had a few shots where the DoF was so short that i ended up with my models eyes in focus but the tip of her nose wasnt. That's at about 6ft.

[Ilyanep]

The reason I was using 1.8 was just to get as much difference with my other lens (which is at 3.5 at the wide side) as possible. I think I'll try it out at 2 or 2.8 later today.

I shoot frequently with the Sigma 50mm f1.4, usually at f2.0 (f1.4 is a little soft, but f2.0 is pretty sharp). Your DOF depends greatly on how close you are to the subject. At 2 feet, it's really tight...less than an inch. At 8 feet, it gets quite a bit larger.

So what I'm saying is, you need to have the focus PERFECT at 2 feet. For portraits, focus on the eyes using manually selected focal points....don't focus on them and then move, your focus will be off. If you hit the eyebrow, the eye will be slightly soft. Here's one I took at f1.4:



Though it's a nice shot (the girl really loved this shot), the focus is ever so-slightly off, as you can see her eyebrow is in focus but her eye is slightly off. This is a dangerously small DOF, but if you pull it off, the photos are FANTASTIC.

At 8 feet or so, you get a much larger DOF. A shot I took at f2.0, about 8 feet or so away: