www.macroshooting.com 

Home

3 Days to Better Live Bug Photos

Hand Held Focus Stacking

Gallery

Exposure Basics
Macro Obstacles
Hardware Basics

Magnification

Depth of Field

Shutter Speed

Macro Flash

Macro Flash Brackets

Tips

Processing

Useful Links

Contact Me

 

Please help support this site by clicking on the Adorama Link before making your next Photographic Purchase


45K2D47DB3

 
 
 
 
 
 
 
 
Depth of Field

Depth of Field - there is none to speak of:

Depth of Field is simply how much appears to be in focus at what distance. In a nutshell, three things control the depth of field, the lens, the distance to the subject and the aperture. Some simple rules:

  1. The further the distance to the subject the more will be in focus at a given aperture (less magnification).

  2. The smaller the aperture (larger f number) the more will be in focus

  3. The shorter the focal length of the lens the more will be in focus (less magnification)

  4. At a given magnification depth of field will be the same regardless of what lens you used. This is a fact!

  5. Lens diffraction will limit how much you can stop down and still have super sharp images.

The shots below are of a machinist's ruler with  the 100's of an inch being displayed.  The ruler was placed at a 45 degree angle from the camera. I set it up like this so that if you wanted you could decide for yourself what was in focus, get out your calculator and calculate what you think the actual depth of field is. The camera was focused on the 6 inch mark for each of the distances and remained the same. The only value that changed was the f stop and shutter speed. The camera was on a tripod with a remote trigger. The ISO was set to 400.

Its really up to the user to test his own equipment to see how it performs at what distance and f/stop. After shooting thousands of bug photos I know that my sharpest are at f/8 but I also know that the trade off between f/8 and f/11 is not much and it is worth having the little extra depth of field.

  Standard 100mm Canon Macro
 
  6 inches from front of lens 12 inches from front of lens
f 2.8 Macro Photography Bug Shots Depth of Field example 1
1/800
Macro Photography Bug Shots Depth of Field example 12
1/80
f /8 Macro Photography Bug Shots Depth of Field example 2
1/100
Macro Photography Bug Shots Depth of Field example 11
1/10
f/11 Macro Photography Bug Shots Depth of Field example 3
1/50
Macro Photography Bug Shots Depth of Field example 10
1/5
f/14 Macro Photography Bug Shots Depth of Field example 4
1/20
Macro Photography Bug Shots Depth of Field example 9
1/3
f /16 Macro Photography Bug Shots Depth of Field example 5
1/15
Macro Photography Bug Shots Depth of Field example 8
1/2
f /22 Macro Photography Bug Shots Depth of Field example 6
1/8
Macro Photography Bug Shots Depth of Field example 7
0.8

So, we don't have much to work with here. At 6 inches from the subject we need to be at about f/14 to f/16 and at a foot away we need f/8 to f/11 (now it is no longer at 1:1) to get any kind of depth of field at all. Now for the very unscientific part, when you look at the photos you will notice that at about twice the distance we have about twice the depth of field - not exact but as I mentioned unscientific. You will also notice the start of diffraction at f/16.

Tip 1:

If you shoot a little further away you can crop the image and get a little extra depth of field. How much you can do this comes with experience.

Tip 2:


Try to get in the habit of focusing a little behind what you want in focus to utilize the all the available depth of field. Not much though, there are some rules saying a third of the depth of field is in front of the actual point of focus. But you can read other articles that say it is in the center. In a nutshell it goes to what is considered sharp and at what distance. There is a good explanation of it on Cambridge In Color's
website.

I know there is a depth of field preview button on the camera, trust me you will not be using it as it provides a dark image and the bug does not wait for you.

Now for a reality check, in the field when you shoot a bug you cannot say, "let me frame the shot, get my ruler and measure how far you are from the camera, calculate what I need for depth of field and select my aperture".  What you will do is know what you can live with. In other words, what gives me the best DOF without loosing image quality.

You should at this point test whatever you are going to use to see how sharp of an image you can produce. Do it in a controlled environment with a tripod and a remote shutter release. In most cases you will end up with f/8 being about the best but you will settle for f/11 as there is not much difference. There usually is very noticeable difference between f/8 and f/16

So, since we have the aperture what we need now is to get a shutter speed that works with it. There is an old photographers rule called "The Sunny 16". Which means that on a bright day at f/16 your shutter speed with be one over your ISO. So at ISO 100 you would be at 1/100 of a second at f/16. I bring this up for illustration purposes as your camera has a light meter and you have to make an adjustments. When shooting with a macro lens or any other of the methods mentioned on the other page for lenses there is a significant amount of light drop off (it is called the Bellows Factor). It differs at each magnification and if you have a dedicated macro lens it will be stated in the manual. (did you read your lens manual) It is usually 1 + magnification. So when shooting 1:1 you would add 2 stops.

Therefore in our above example we are now at 1/100th of a second at around f/8 (two stops below f/16) on a very bright sunny day. There is another rule that says to reduce camera shake when hand holding a camera you should be at "1/over the focal length". This as a rule works pretty well, you need to be at a 1/100th of a second when using a 100 mm lens. This naturally is because of the magnification. When shooting with a macro lens this does not apply because there is more magnification so you most likely will not be able to consistently hand hold your 100mm (or 1:1 magnification lens) at 1/100th of a second and get motion free shots.

If you are real lucky you may get a few shots at 1/125th of a second without shake but you cannot count on it. However, what you will find with a lot of experience is that you will get decent shots (not great) between 1/160th to 1/200th of a second on a somewhat consistent basis perhaps a little over 10%. 

Camera Movement is the Number 1 reason for poor Macro Shots

Confused yet? well to sum it up ideally we need a shutter speed of 1/200th at f/11, and we are at 1/100th at f/5.6 at ISO 100. Since each change in exposure requires a matching one. If we go to ISO 200 we can double our shutter speed to 1/200th of a second. If we double the ISO again to 400 we can go from f/5.6 to f/8. And there you have it in theory. What you will find though is that on a bright sunny cloudless day you will really be between f/5.6 and f/10 at ISO 400 at 1/160th of a second. Again these are general rules and they are close.


I went to a macro workshop that focused on taking photographs of insects. The instructor said professional photographers always take lots of pictures and just throw away the bad ones.  He went on to say sometimes he takes 2-3 thousand to get one shot. Reality is you should be getting about 30 percent that are really good. His keeper out of the over 2000 shots was one I would have trashed. I am not saying mine are the best at all, just better than what he was producing.

So, it can be done or we can continue to increase the ISO which leads to new issues or add flash. Keep in mind we are only shooting on exceptionally bright days in direct sunlight (leaves out a lot of spider shots as quite a few of them hang out in the shade) and counting on a little luck. The shots on the banner of this page were all hand held in direct sunlight with no flash so it can be done and it really is fun, the reason being is so few are any good that when you get one you are very excited. The photos in the Gallery were all shot with flash. Once you start adding flash things change and fast. With flash you can remove the camera shake and get a little extra depth of field. What you will end up doing is using the flash duration to remove the camera movement not the shutter speed.

My advice would be to practice without flash as you will quickly learn how to frame and focus your photo with a minimum depth of field. Once you get this down and you throw in a little extra depth of field and remove camera movement it becomes real easy to consistently get good shots. Remember the tips mentioned above, here they are again.

Tip: if you shoot a little further away you maybe able to crop the image and get a little extra depth of field.

Tip: get in the habit of focusing a little behind what you want to utilize the depth of field.

Continue to Shutter Speed