I’m often asked how I get my images to be so soft and how do I focus. So, I decided to do a small comparison so you can see what I've done.
My go to lens is the Nikkor F2.8 Macro lens. The F2.8 lens is what is considered a wide open lens and a fast lens, the reason is the amount of light that can pass through an F2.8 lens is considerably larger than the amount of light that passes through a lens at F16 or F22. I remember when I first started to learn this, it was so confusing to me, because I’m a logical thinker and what I’m going to tell you next may not be logical for you….
An F2.8 lens is considered a large aperture, the smaller the number (F2.8) the wider the lens opening, the wider the lens opening means more light coming through the lens = large aperture. The lens wider opening allows the maximum amount of light. I know that part is obvious. Large aperture means you are shooting at a shallow depth of field, and that means a smaller focus point. I have literally had a sliver focus (the image below), I am literally focusing on one tiny sliver of detail as seen below and then there's a gentle fall off from sharp focus to the softness.
Sliver focus, notice the smallest of detail is in focus and the rest falls off.
Smaller apertures or large F-stop numbers allow less light, they have smaller lens openings and they produce more detail throughout the image. If shooting a landscape at F16 you normally choose infinity as your focal. This allows a lot more of the image or the entire image to be in focus. Now apply that to a flower, if you shoot the flower at F16 most or all of it will be in focus. You will also notice the background has more detail than you'd probably like. Distracting elements are all the sudden noticeable and the subject is not separated from the background, it does not stand out. These are all the result of shooting at a smaller aperture.
There are times when you may want more detail, say for instance when you're documenting a plant. In this case, it's more about the plant then being creative. The image is used for something entirely different.
Image details 105mm Macro lens, F4.5, ISO 400 1/125 sec. (image on the right)
Details for the image below 105mm Macro lens, F9, ISO 400 1/25 sec (image below)
Notice the difference between the two images, the upper image on the right has more softness in the background than the image on the left. If the image was shot with F2.8 imagine how much softer the background would be. Something to consider if you do shoot F2.8 to F1.6, the over all image can be a bit soft. If you want to blow the image up really large the focus may fall off more than you want. It's something to consider if you're shooting at larger apertures.
The image below was taken at F14, ISO 320, 1.0 sec
This image was take at F7.1, ISO 320, 1/4 sec.
Notice the softness of the image on the right. I know what you're thinking and I get asked this a lot, you're wondering why the image on the right was taken at F7.1 and yet it still has a lot of softness? The answer is because I am extremely close to the flower. All the images above were taken with the same lens, my 105mm macro lens.
I do like to change it up a little from time to time. However, 99% of the time I use my Macro lens. I may start off with a creative lens but ultimately I go back to the macro after a little bit of time. It doesn't have anything to do with the lens but it has everything to do with my comfort. I'm used to using the Macro lens, it's what I'm comfortable with. It is not always good to go back to what you are comfortable with, that's why I do try it from time to time. I will admit, I need to do it more because I do believe in stretching our brains. If we get too comfortable then we get lazy, brain wise, we don't experiment we don't grow. I think it's always important to grow.
I have a couple of lensbaby's the Velvet 56 and the Control Freak, I haven't use the Control Freak for a while so I don't have an image readily to share.
Velvet 56 Lensbaby
I bought this lens because I wanted to go even softer and the Velvet 56 allows that. F1.6 is pretty soft, I don't use it a lot, but I need to. I do love the softness of this lens.
I hope I’ve given you something to think about. Think about it and take the time to get a feel for it, then try it. Go out and play with the Fstop see what you find for yourself