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View Full Version : Soft focus issues on a model shoot. Help please.



abitfishy
01-05-2010, 1:01am
Today I did my first real model shoot and the one thing I found aftewards is that a LOT of the photos I took were soft, even possibly out of focus, although it wasn't obvious until they were zoomed closer to full size. When I resampled them lower though may were acceptable. I'm wondering if it might have been my settings not being ideal. I used the D90 and an SB600 on camera for fill flash, with the 50-150 Tokina, on a large apeture, on the picture mode 'Portrait' (not the exposure mode), and I used the settings where it chooses the focus points it thinks you want (can't think of what its called).

I'm wondering if I should have just used 'Standard' Picture mode with maybe a -1 sharpening, and kept it on single focus point, focused and re-framed. Thoughts? Other possible reasons for focus issues? I was happy with the shoot, but would have been overjoyed if more didn't have the focus issues.

Thanks

JM Tran
01-05-2010, 1:07am
your mistake was allowing the camera to choose the focus points for u, it does not know exactly where u want to focus on - so next time use the centre AF point, focus and recompose and shoot

try it in Aperture Priority mode

abitfishy
01-05-2010, 1:10am
Thanks for that. I thought that might have been the problem because many were sharp.

Yes, it was in AP. The Portrait mode I was referring to was the 'Picture mode' ie Normal, standard, vivid, portrait.

farmer_rob
01-05-2010, 8:42am
Did you shoot RAW or jpeg? If RAW, the picture mode can be changed in ViewNX or CaptureNX (and to a lesser extent in Adobe Camera Raw).

I don't think this will fix your problem though - it is more likely that it is the focus points (like JM Tran said). ViewNX/CaptureNX allow you to see which focus point was used.

Since ViewNX is free, it is really useful to have on your computer, just to be able to fiddle with picture modes and see the focus points.

abitfishy
01-05-2010, 11:07am
Thanks Rob. I shot RAW with JPEG fine.

Just checked out some of them. Some did seem ok with the focus points but they could be shutter speed related, some locations were pretty dark. Some focus spots were way off but some were perfect and still too soft. The other thing I'm wondering is most were done at f2.8. From what I read such a large aperture can sometimes be a little too soft and to stop down a bit, am I correct? I was trying to ensure good out of focus backgrounds, maybe even F4 or 5.6 would still be ok and a tad sharper?

Wayne
01-05-2010, 12:15pm
Shooting wide open on most lenses is going to be softer than it would be stopped down a stop or two. Remember that the "Bokeh" or background blur is also affected by your distance to the subject and the distance behind the subject to the background features.

Shooting f5.6, you need to be close to the model and the model needs to be as far as possible from the background to achieve really OOF background with that lens. The wider than lens, the less OOF backgrounds are likely to be. If you shot it with a 400mm for example, the DOF at f5.6 would be somewhat smaller than at 50mm with the same f5.6 setting all else being equal (except your distance to model will of course be greater with the 400mm).

As already said, for static subjects, never let the camera choose the focus point.

farmer_rob
01-05-2010, 12:15pm
I don't have a big f2.8 lens, so my comments are theory more than experience. However, I have found with my f1.8 35mm that getting accurate focus wide open can be a lottery. To get the nice blurred background you really need the 2.8 IMO (f4.5 just doesn't quite do it for me.)

I have found that low shutter speeds can be a nightmare if handheld - anything less than 1/60 under ALL circumstances, and 1/200 at 200mm. Nikon claim the VR makes a difference - I find it doesn't at long focal lengths (also check out Thom Hogan's comments on VR (http://www.bythom.com/nikon-vr.htm)).

On a tripod, the shutter speed issue is messier - how solid is your tripod? (I have found through experiment that there is clear shutter-induced vibration at slower shutter speeds on my cheap/old velbon with my 70-300mm, VR not withstanding).

With the D90, you have a bit more latitude for high ISO - i'd risk higher ISO rather than lower shutter speed.

Perhaps an example of the softer shot vs the sharper shot might help.

Edit: looking at you gear list and wayne's comment, I realised I was assuming a 70-200f2.8 and was wrong. I'd be wary about wide-open on the non-Nikon lenses unless you can document their sharpness.

abitfishy
01-05-2010, 12:34pm
The pics were all handheld. A few are also soft all over, so I would say its definitely a combination of shutter speed, focus points and wide aperture. I'll keep this all in mind next time. Thanks.