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Hi all!

Couple of quick things I'd like to get people's opinion on.

1. I don't see the point of having X number of focus points. My D40 has three and I don't even use this many - I use single point focus (centre-point), focus and recompose before shooting. I can see the advantage of multiple points for sports photography - but what do other people do? Do you find yourself using a single point most of the time, or do you often use more than one?

2. I use AUTO-ISO on my D40, which raises the ISO as and when required. However I'm wondering if other people actually find this useful, or tend to more often manually set ISO? Or do you set a minimum ISO above 200 depending on shooting conditions (low light etc).

Anyway these questions are probably poorly conceived but I hope you get the gist of what I'm asking!

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Nikon D40 / Nikon D5100

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18-55 VR f/3.5-5.6
55-200 f/4-5.6
50 f/1.8

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1. Agreed - I only use just one. However, I am aware that others do use more, so my comment is limited due to my lack of experience (only at this a year).

2. I do see the advantage to use auto ISO. On my D200, you can set the lowest shutter speed the camera will go to (in aperture priority mode) before it bumps up the ISO. Really cool feature, which may or may not be common in other DSLR's. However, to answer your question, I never use it. Since I have and older body I'm very weary of pushing the ISO. I typically shoot in fully manual with an SB-600. Thus eliminating (or drastically reducing) the need for ISO.

Hope my answers helped.

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Trevor Harris

Nikon D200
SB-600
YN-560 II
YN RF 603 x 4
Tamron 17-50mm f/2.8
Nikon 50mm f/1.8

I use only one focus point, it would be useful if anyone can give an example of using of different points.

I also use ISO especially for subdued light in a local rain forest and when using a 70-300mm lens for surfing shots, I use ap mode and increase the ISO to get a speed that will not give me camera shake on my 300mm non VR lens.

Cheers

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Nikon D7000, D40X, Nikkor 18- 200 VR II, f3.5-5.6, 70-300 AF non VR, Kit Lenses.

I'm another who only uses one focus point but does change the ISO off auto on a regular basis.

I think 75% of the time my camera is on Av with ISO on auto but that other 25% is important

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Canon EOS 550D (with Magic Lantern)
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Manfrotto 190CXPRO3 with 496 Ball Head. Gorilla Pod SLR
Canon Powershot A720IS with CHDK and intervalometer script. Pentax Optio W90

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I always shoot with the full 39 point AF when shooting sports, but otherwise I generally use a mix of full AF, partial AF or just the one point. Unless I don't have the time to recompose and need to quickly get the shot, one point generally does the job. If it's that important though, sometimes I'll pre-focus so that when the subject enters the frame the focus will already be spot on.

Regarding ISO, I never use auto ISO just so that I can have complete control over my exposure. I shoot using aperture priority mode 99% of the time, so if I need to adjust my exposure I'd rather change the aperture than the ISO. For example, in low light I'd rather shoot at f/2 and ISO 400 rather than f/2.8 and ISO 800. After ISO 800 on my D7000, I do see a fair increase in noise, so I don't like turning it too high. If that doesn't work well enough, I can always use my SB-700 flash and set my ISO again. Another example would be outdoors, I'd rather shoot at f/5.6 and ISO 200 than f/4 and ISO 100, the tiny extra bit of noise won't affect the IQ enough to justify setting the ISO down to 100, but the extra sharpness using f/5.6 over f/4 is quite a bit. Using Auto ISO doesn't give me the control that I like to have, which is why I prefer manual.

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-Evan

Gear: 7 Nikon Nikkor AI-S and AF-S lenses, SB-700 flash, Nikon D7000, Nikon FM, variety of accessories

"There are no rules for good photographs, there are only good photographs."
- Ansel Adams

There are a number of web pages discussing the topic of multiple focus points. One of the more technical and less subjective is here

http://www.cambridgeincolour.com/tutori ... ofocus.htm

and for more discussion based see

http://photo.net/canon-eos-digital-camera-forum/00IMzA
http://www.thephotoforum.com/forum/beyo ... oints.html

From a quick read it seems some manufacturers may use the information from multiple focus point to help with things like scene recognition as well as giving you the ability to use part of the subject not in the centre of your shot as a focal point (without having to focus lock and move the camera).

I would think if you are photographing a group of people or an object that is not flat it might be useful to have more than one reference point as well as the obvious advantage of tracking moving objects.

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Nikon D90
Nikkor AF-S DX; 18-105 f/3.5-5.6G VR, 55-300 f/4.5-5.6G VR, 35mm f/1.8G
Speedlight SB-700

http://keystrokesukimages.com

I've got different shooting banks on the D700, so I have 3 custom setups

Handheld, Auto ISO to a max of 6400, min shutter 1/80th
Manual ISO
Handheld, Auto ISO to a max of 6400, min shutter 1/30th

1 and 3 are for different lenses, and 2 is mainly for tripod work or where I want total control myself.

Re focus points - a good example of using different focus points is when focussing on a tripod rather than focussing and recomposing

keystrokesuk, thanks for the links. This has helped me understand the focus points issue, but I'm still wondering what best practice is for the ISO...

For example, using AUTO ISO, if I'm in aperture priority mode on my D40, shooting indoors, the camera will selected my shutter speed based on ISO200 when it would make more sense to manually crank the ISO up to 400 or even 800, correct? (assuming I'm not using a tripod).

Would it make sense to use AUTO ISO all of the time EXCEPT when filming in low light situations?

Thanks everyone for your replies!

_________________
Nikon D40 / Nikon D5100

Visit my photograph portfolio and personal blog

18-55 VR f/3.5-5.6
55-200 f/4-5.6
50 f/1.8

Follow me on Twitter: @stevesayskanpai

I never use auto-ISO. I set the ISO manually to 200 in bright conditions and eve then have to use -0.7 exposure compensation usually to avoid blown highlights. Most Nikon DSLRs tend to over-expose in my experience.
If the light is not so good I increase the ISO maually and take shots until I can achieve the aperture/shutter speed I want. I am sure you know you really want to keep the ISO as low as possible to avoid unwanted noise. Some cameras are better than others at higher ISO values so it is important to know your camera and what it is capable of at any given ISO value. Auto-ISO can play tricks sometimes and raise your ISO to an unacceptable level. IMHO it's always best to keep control of it your self.

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Nikon D300 D80 D40 18-55mm 18-70mm 18-135mm 55-200mm 18-200mm 28mm 2.8f 50mm 1.8f 85mm 1.8f
Panasonic DMCFZ28 Slik Pro 700DX

I know a little about a lot, a lot about little and everything about nothing.

That's the point with Auto ISO - set the maximum at an acceptable level for you. If you're shooting anything fast paced in varying light levels then it's a life saver.

I have Auto-ISO (almost) always on with a floor to the shutter time that I unfortunately have to adapt as Nikon did not think of tying that to e.g. the focal length. My range is normally 1/30 sec or 1/60 sec as the floor and ISO 1600 as the top ISO that I would allow.
With these setting I normally forget about it until e.g. I'm shooting moving subjects and definitely need a faster shutter-speed.

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Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews, My Pictures, My Photography Blog
D800+assorted lenses