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Akshay Kumar Manjunath
01-06-2010, 09:52 AM
Dear All,

When i take snake photographs, I focus on the head and what i have noticed is the second part of the body will be out of focus.

I think this photo would have much better if the second half was in focus.

So can you suggest me how to focus the entire body.

Canon D1000
MACRO MODE
18-55mm lens.
Regards,
Akshay

Mrudul Godbole
01-06-2010, 11:41 AM
The composition is nice. The low angle is good. What was the shutter speed and the aperture? The eye is not sharp, maybe there was a movement. To get the whole body in focus, you need to have a higher depth of field.

Please post the EXIF details, so that will help in giving proper suggestions.

This is some information about aperture and depth of field -

Aperture
Aperture defines the amount of light that enters a lens. A lens consists of diaphragms which help to vary the aperture of the lens. Usually 8 diaphragm lenses are common. The aperture is represented by the F number. A higher F number such as F4 or F2.8 means that the opening of the lens is more in comparison to F8 or F11 say. The minimum and maximum values of the F number are dependent on the Lens. F2.8 lenses have larger apertures and hence larger glass is used. Therefore they are bigger in diameter and are heavier. The F number is calculated by the following formula.

F number = Focal Length/Diameter of Aperture

A larger aperture will allow more light to pass through the lens, but the depth of field or the region in front and behind the subject in focus would be shallow. A lower aperture on the other hand constricts the amount of light which enters the lens but the depth of field or the DOF is much more. Therefore a greater region around the subject will be in focus. A rule of thumb for landscape images is to use narrower apertures or higher F numbers. This facilitates a greater region in the image to retain focus. To see how much the DOF is, one can use the DOF preview button in front of the camera. It stops down the lens to the desired aperture and the corresponding DOF can be seen in the viewfinder.
The Aperture values of Lenses available in the market are usually in the multiples of Square Root of 2 (1.414) ie one ‘Full Stop’. The F numbers are F - 2, 2.8, 4, 5.6, 8, 11, 16 etc. The intermediate F stops are however more numerous. Usually upto 1/3 stop least counts are used.
The various combinations can be seen from this table. The "Full Stops" are in bold.

Rule - “A Lower F number when you want more light to enter the lens and have a shallow depth of field and a Higher F number when you want a higher Depth of Field to be covered in the image”

Akshay Kumar Manjunath
01-06-2010, 12:59 PM
Dear Mrudul,

Thanks a lot for the information

sorry, i will post the EXIF details.

Regards,
Akshay

Abhishek Jamalabad
01-06-2010, 01:58 PM
Nice composition. It would be very difficult to get the whole body in focus, especially when you're shooting from very close to the snake with the 18-55. I feel you should set the aperture to the highest possible value (without letting the shutter speed drop too low) and then choose an angle such that the more important parts of the image are in focus.
For example, a side-on shot of the head would have given you an image with most of the head in focus.

Akshay Kumar Manjunath
01-06-2010, 09:36 PM
Dear Mrudul these are EXIF Details

Tv(Shutter Speed) 1/60Sec.
Av(Aperture Value) F5.6

ISO Speed 400
Lens EF-S18-55mm f/3.5-5.6
Flash On
White Balance Auto
AF mode One-Shot AF

Regards,
Akshay

Nikhilesh Mahakur
01-06-2010, 10:23 PM
A lovely image.
The vine snakes make fantastic compositions, I love your composition except that focus is lost on the nose and head.

A bit of focus on the nose and eyes ( already well captured) would have made this a fantastic image.

Good work!! Look forward to more.

Am beginning to find a lot of my fav reptile photographers here :)

Sabyasachi Patra
02-06-2010, 02:22 PM
Beautiful snake. I hope you can get an opportunity to create a sharp image later. Thanks for sharing.

Cheers,
Sabyasachi

Bibhav Behera
02-06-2010, 05:43 PM
The composition is nice. Had you got the head sharper, it would have made this better. Thanks for sharing.