How to achieve better DOF with Macro?

<p>Hi,</p>

<p>I've just started practicing with a little Macro photography but I am running into a jam in regards to depth of field. This is a new technique for me so if I seem completely ignorant, well, I am. I am starting with the centers of flowers but no matter aperture, my DOF is still quite shallow. For example, I have been toying around with red petunias. If I get the stamen crystal clear, the veins in the petals become lost. I really would like them both to be clear. I tried backing up a little and then I added a +4 magnifying filter. I've shot F5.6, F7.1, F9, F10, F11 and F13 I shoot completely manual so it is user error I am sure. </p>

<p>I have three lenses to choose from - the kit lens 18-55 (not excited about it so much), a 50 mm and a100-300. Unfortunately, my totally awesome 18-135 walked out of my house and I have not yet replaced it.</p>

<p>Perhaps I need to make another investment? </p>

<p>Maybe I need to change my auto-focus to manual? </p>

<p>Thank you,</p>

<p>Bonnie</p>

<p>Having a very shallow DOF is just the nature of macro/closeup photography and switching lenses will have no real effect. If you're shooting on a tripod the best way is by using focus stacking where you take a series of shot focused on different parts of the object then combine them into one shot using software. dpreview has just posted a "how to" for it: <a href="http://www.dpreview.com/news/2013/04/11/focus-stacking-in-macro-photography">http://www.dpreview.com/news/2013/04/11/focus-stacking-in-macro-photography</a></p>

<p>And if you're really carefully you can even do it handheld, though the final results won't be as good as if you were using a tripod.</p>

<p>If you have enough light, I've found that you can go to around f/16-f/18 without getting too soft. Past that you start noticing diffraction related softness. I gotten a few images with (for macro) impressive DOF at around f/22, and as long as you don't enlarge to image past screen size, they still seem quite sharp.</p>

<p>I try not to go past f-16 if I can help it, try to line up the elements you want in focus so they are parallel to the film/sensor plane helps some. I like doing wildflowers and a little manipulation of the subject helps.</p>

<p>Shallow dof is inherent in macro photography and there is not much you can do about it. If you are serious about macro photography, consider getting a dedicated macro lens. Their apertures go down to f32 or smaller which will help with the dof problem. Dof decreases with focal length so try shooting at the shorter focal lengths such as 50mm. One of the most popular focal length for a dedicated macro lens is 50mm.</p>

<p>The reason macro lenses are so expensive is they are much higher quality than regular lenses. They are designed to produce good images at small apertures and have a much flatter focal plane. For most photographs they are over kill but macro photography, they are what you must have if you are serious about it.</p>

<p>Danny Low</p>

 

<p>As far as the focal length influencing the DOF goes, my personal experience seems to be that it's the magnification that matters (along with the aperture). It seems that if I fill the frame with a subject using my 30mm macro or with my 100mm macro lens the DOF is pretty much the same at the same f-stop. What does change is the distance from the subject and with that the perspective. The greater the magnification on the sensor the smaller the DOF. Although it does seem the backgrounds blur more heavily with the longer lens.</p>

<p>As the other posters have said, it's not so much anything that you are doing wrong, but more the nature of physics. The closer you get to the near focus point of a lens, the less DOF you get. There's nothing you can do to change that. There are things you can do to mitigate the effect, however. Focus stacking can give you almost unlimited DOF. Stopping the lens down more helps, but at the cost of losing some sharpness to diffraction. Dedicated macro lenses do tend to handle this better than general purpose lenses because they are generally optimized for shooting at close distances. If you do stop down, use of a tripod becomes almost imperative. You are already losing some sharpness to diffraction. You don't want to add motion blur on top of that.</p>

<p>One thing that does bear mentioning here, I think, is that it's not always necessary to get everything in focus. Selectively controlling the depth of field is one of the easiest ways to isolate the subject of a picture. The eye is naturally drawn to the part of the picture that is in focus. Portrait photographers use this all the time to draw attention to the subject of the picture. It can be very effective in macro photography too. For example, in the shot below I could have easily stopped down more and gotten the petals on the front of the flower in focus, but I felt like that would distract the viewer from what I felt was the more interesting part of the picture. I used shallow DOF (and placement in the center of the image to direst the viewers eye where I wanted it to go. The rest of the image is basically just background information.</p>

<p><a title="through petals by cory ammerman, on Flickr" href=" src="http://farm7.staticflickr.com/6211/6259180705_f11df20e17_z.jpg" alt="through petals" width="640" height="425" /></a></p>

<p>Additionally, using a shallow DOF, I feel, gives an image more of a feeling of depth. More of a 3D effect. In this shot, by blurring all but a small part of a Crape Myrtle bloom, I'm attempting to let the viewer know that this part is much closer than the rest of the bloom. The result is that the part of the bloom that is in focus almost seems to be popping off the screen. That's the effect I was going for anyway.</p>

<p><a title="crape myrtle bloom by cory ammerman, on Flickr" href=" src="http://farm7.staticflickr.com/6177/6259180623_cf647b9d22_z.jpg" alt="crape myrtle bloom" width="640" height="425" /></a></p>

<p>In this image, I'm again attempting to draw the viewer's eye to a certain part of the scene. Additionally, I've included an out of focus background and foreground to give the viewer visual clues that they are just looking at part of the branch and that it does continue out of the image. Again providing more depth.<br>

<br /> <a title="plant with horns by cory ammerman, on Flickr" href=" src="http://farm9.staticflickr.com/8254/8641920561_88166c81b5_z.jpg" alt="plant with horns" width="640" height="456" /></a></p>

<p>By contrast, here's a shot where pretty much the whole flower is somewhat in focus. To me, it looks very flat and uninteresting. It appears very two-dimensional and pretty boring actually.</p>

<p><a title="img120 by cory ammerman, on Flickr" href=" src="http://farm9.staticflickr.com/8401/8637596335_e297423170_z.jpg" alt="img120" width="640" height="404" /></a><br /> All that is probably more information than you were really looking for, but I don't really have a lot going on this morning, so there you have it.</p>

<p>If you can find an old copy of John Shaw's books on nature or Macro he moves through and illustrates several approaches to maximize DOF. More or less though Robert's description is how I approach it. Admittedly with my macro lenses I do go down as far as f22 occasionally, but f16 is generally what is recommended and I also try any move about the subject to get as much in focus as possible.</p>

 

<p>As Siegfried says, Depth of Field goes up or down with degree of magnification, regardless of the lens system (if aperture is kept the same). So one way to get more DOF is to use less magnification -- getting both the flower center and the petals with their veining sharp by backing up and taking that blossom's context more into the frame with it.</p>

<p>Keeping close in and tight might be done, by using smaller aperture to increase DOF, but as has been mentioned F/16 and especially smaller introduces diffraction and decreasing aperture requires more light--either through longer exposure (with tripod) or supplementary lighting, like flash. I prefer natural light to flash, but if the flowers are being ruffled by a breeze, longer exposure is out of the question...unless you want very impressionistic patches of color instead of flowers.</p>

<p>I like Cory's suggestion about trying to get the one (or few) areas of the flower you want to draw the viewers' eyes to most into the same focal plane and allow the rest to blur creatively. His examples are great. An example I can share verbally (the old slides are unscanned) is when I was trying to photograph honey bees on milkweed flowers. I wanted to show the pollinia (little golden saddlebag-like pollen sack pairs) caught on the bees legs, and if I also got one of the bee's eyes, and part of the flower really sharp too, what was happening really came through.</p>

<p>If you want to delve into the technical issues, I would most recommend Lester Lefkowitz's MANUAL OF CLOSE-UP PHOTOGRAPHY, which is very clearly written and extremely well illustrated. Unless there is a revised version, it is totally pre-digital-age, but the issues you asked about transect both digital and film photography. You might find it in a library or used somewhere.</p>

<p>Thank you all very much! Your information has given me much to consider and so now I feel a little more confident. I will follow all the suggestions provided and just keep shooting. I posted a few in my galleries just in case you are curious.</p><div></div>

There are focus stacking techniques a and software you can use.

 

I've used Helicon Focus and it works great

 

http://www.heliconsoft.com/heliconfocus.html

<p>1. stop down to smaller aperture<br>

2. shorter focal length<br>

(a depth-of-field calculator, easily found online, can help you see the impact of solutions 1 & 2)<br>

3. focus stack multiple images<br>

4. tilt-shift lens</p>

<p>DOF is quite shallow in macro work. At 0.5x magnification and f 16, DOF is 1/16 of an inch; at 1.0 x magnification at f 16, it is only 1/48 of an inch. And diffraction(image softness) can start to appear at f 11 or f16 on certain digital sensors. Aside from focus stacking already mentioned, the only practical thing to do is reduce magnification--move back from the image. Personally, I like to use the small DOF as a creative tool and often set my f stop wide open at f 4.0 to reduce DOF and blur the parts of flowers I cannot get sharp. Try it and see what you think. For my flower images, I like a macro lens with a focal length of about 90-105mm vs the shorter ones at 40-60mm. Joe Smith</p>