D600 - crosshair AF sensor points - more accurate?

I was just doing some portraits. I used the AF sensor more on the right side - I was shooting vertical composition so in vertical they are the AF more towards the top. Are those less accurate? AF-S single point. The eye wasn't that in focus with much of the shots.

 

Cheers.

The D600 (and D610) has the Multi-CAM 4800 AF module. The center 3x3 AF points are of cross type. The others are not.

Does the cross type work faster or do they work more accurate as well? If the non cross type work less accurate, why would anyone use them? Things like sports or quick portraits shooting would be quite useful.

Cross type AF points are sensitive to contrast in both vertical and horizontal directions. Since you already have the D600, experiment with the center 9 AF points (3x3 matrix) vs the others and see whether it makes a difference.

 

For FX, I only like the Multi-CAM 20000 AF module, found on the D5 and D850.

Edited May 22, 2018 by ShunCheung

Generally speaking with all Nikon dSLRs do you guys use the non cross type AF points much? Is it specifically for certain subjects with horizontal contrast or do you some of you use it even thou it might not be the most accurate but it is still an OK accepted photo?

 

I pretty much just use the middle AF point and recompose, I don't do action or wildlife so I always had that freedom but seldom people which I found out lately.

I do use them (with the CAM 3500 module). The outer areas are less sensitive, so for fast work they're sometimes a bit infuriating, but in good light it's not often a big issue for me.

Focus and recompose is OK if you have enough depth of field, but at shallow depth of field, close distances, it doesn't work since you rotate while recomposing, which means you move out of the plane of focus. That said, ultimately I trust my eyes - viewfinders work well enough for me in that respect.

I've generally left my AF system on 3D tracking unless I actively need it to be locked where I point it. I place things manually, but then use the 3D tracking to allow for slight movement of the subject or moderate recomposing.

 

Focus and recompose is dangerous on a high megapixel camera - as you rotate, you're taking the focal plane with you, which moves it away from the subject you're focussing on. I think it's Hasselblad who has a system based on accelerometers in the camera to compensate for this, on a body with a single autofocus point; I always at least use the nearest AF point I can. Unless the autofocus is struggling, I also tend to try to keep AF active to allow for any sway in my holding of the camera, or movement of the subject. Unfortunately the nearest AF point sometimes doesn't quite get to my subject, due to the limited AF coverage on full-frame bodies.