Camera to subject distance

[Sightpicture]

I joined the forum recently and have seen truly stunning bird and wildlife images by the members. The composition is amazing and the photos are incredibly sharp. My question is, at what point is the subject too far away for a good sharp image? Obviously closer is better but in going out to the wildlife refuges Ive seen photographers with 500mm lens taking images of birds and wildlife that are quite a distance away. Is there a general rule of thumb that is used?

Im not sure if Im posting this in the right forum but I'm mainly interested in birds and wildlife.

 

[Overread]

Your question is tricky to answer because it depends what you've got and what type of photo you're after.

In general there are 3 aspects that will affect image sharpness (excluding native camera+lens sharpness).

1) Camera shake; affected by the holding of the camera and by the focal length. The longer the focal length the faster your shutter speed has to be. A rough rule of thumb is 1/focal length=minimum shutter speed for a sharp shot hand held. That assumes a good level of fitness for the lens and a good posture.
For a 500mm lens that means you're up to 1/500sec minimum and for big lenses like that most people often need a bit more.

2) Subject motion blur; movement of the subject is the other area and here you've got rough limits. 1/500sec is really your slowest rough limit; any slower and you're introducing more and more chance for the motions of the subject causing blur. Of course that's just a rule of thumb;
If your panning a shot you might be able to use a slower shutter sped
If the subject is asleep or at rest you might get away slower
If the subject is running/sprinting or performing other fast actions you might well need a lot more.

3) Haze from air. Not really an issue most of the time until you're using something around 1000mm in focal length (so a big lens plus teleconverter). However sometimes strong heat can cause haze to be more apparent and more problematic in some situations. Thick fog or other particles can also have a similar effect.


As for a rule of thumb for focal length - 100mm longer than whatever you have at present . Longer is generally better most of the time which is why wildlife is often a very expensive area of photography. 300mm is where it starts, but many really start at around 400mm. Anything greater is worth considering if you can afford it; but also have a mind that some lenses can take teleconveters. A 300mm f2.8 with a 2*TC is now a 600mm f5.6 lens for a lot less than a 600mm lens and lighter too. Sure you've lost some image quality but you'll still get usable images if you stop down a bit from wide open.

Another key point is to consider your ISO. An oft quoted mantra is "Keep the ISO as low as possible" and whilst this is true; its bad advice in general. With wildlife you've got to have that shutter speed fast - so often as not unless you're in blazing sunlight (which introduces its own problems) you'll be wanting to have ISO 400 or even 800 as your starting point for ISO. Only lowering it if you're getting fast shutter speeds and can afford to drop them a little.

 

[SCraig]

The other thing that needs to be considered is the camera body. A high-resolution body allows a good bit of cropping without losing a lot of detail. This Sandhill Crane was shot at about 60 meters with a 500mm lens and cropped significantly.

 

[matthewo]

I agree with the above, depending on a lot of things like shutter speed, iso, lens sharpness, and camera mega pixels(if cropping)

Obviously the most detailed photos are going to be when you can fill the frame or even get tighter shots of just a birds head. Its also about lighting striking the birds feather or the subject in a way to bring out details to make an image look sharper then one with less detail because of heavy shadows.

Once you start shooting regularly you will find out what subjects to just not bother taking a photo of because you will have an idea for the optimal distance to get the photo you want.

More and more i find myself just passing up distant subjects because i know its an image i will probably never use because of distance

Its a different story if you want an environmental image where a lot of the image importance is things other then the primary subject

 

[Sightpicture]

Overread thanks for the insight. Never really took the environmental factors into consideration and how they play a big part.

Matthewo I know exactly what you mean Ive tried to slow down when it comes to taking photos of distance subjects I have to consciously tell myself its not worth pressing the shutter.

 

[baturn]

As always, Overread covered the subject very well. As to whether the long shot is worth it or not, for me it is the rarity (personal) of the subject that governs the distance. To me a not so good photo is better than no photos at all.