How to Use Maximum Aperture Effectively ?
This article is made because some of my friends confuse about aperture, DOF, hyperfocal distance, etc. I also realize that not many people understand this very well and I think it’s good to make this article. Honestly about aperture, DOF, hyperfocal distance, etc you can find the detail in DOFmaster – but my friends still don’t understand so I try to write this article.
In this article I just explain how to use maximum aperture effectively which is very useful for portrait photography. For landscape photography you will need to know how to use minimum aperture effectively and keep everythings sharp. So it will be totally different. Anyway for landscape photographers you should understand hyperfocal distance to keep everythings sharp. About hyperfocal distance you can read here.
Before we go into the detail, I need to explain why I used EF 85mm f/1.2L II and EF 35mm f/1.4L…. The reason is their maximum aperture f/1.2 and f/1.4. Of course using f/1.2 or f/1.4 still need to take care the detail of the object and blur the background. Keep the detail of object isn’t so easy, you need to understand “near limit” and “far limit” of depth of field.
In order to know DOF, near limit, far limit you can download DOFmaster depth of field calculator or you can use online depth of field calculator. In this article, I use online depth of field calculator.
Input parameter: EOS 5D, 85mm, f/1.2, 2 meter (assume the distance from front of lens to object is 2 meter). Remember that you need to input actual focal length and about the subject distance is measured from front of lens to object (for detail see in FAQ). You can see near limit 1.98m and far limit 2.02m, it means the accaptable sharpness area is the area within 1.98m to 2.02m. The total of DOF = 0.04m.

Now with the same parameter except the aperture ~ I change the aperture to f/4 and you will notice that the total depth of field also increase become 0.13m.

Next experiment if I increase the subject distance become 4m, total depth of field also increase become 0.52m.

After you understand near limit, far limit, and DOF you should know that in portrait photography generally you need to keep two eyes sharp. But in reality you only can focus on one eye so be careful when the model isn’t facing (frontal of) your camera. You can see example below.
This is one of my photo from Photobase Player album, I use EOS 5D + EF 85mm f/1.2L II with f/1.2:

Now look the detail in face:

In this case I only can keep one eye sharp because the model pose is not facing (frontal of) my camera so the distance between my camera to left eye isn’t same with right eye. If you want to keep two eyes sharp so you need to use f/2.8 or f/4 (maybe). For me it’s okay to get this kind of result, looked a little bit artistic hehe…..
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CONCLUSION:
1. Increasing the aperture (small number of f, for example f/1.2) will decrease total depth of field.
2. Increasing the subject distance will increase total depth of field.
3. Be wise setting the aperture especially if the object isn’t in one plane (not frontally facing the camera).
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I hope from this article you can optimize the value (aperture and subject distance) to get the object sharp and the background totally blur ~ anyway if you have comments, suggestions, or critiques don’t hesitate to write it. Thanks…










thanks buat infonya…
moccavanilla
June 13, 2009 at 7:56 am
@moccavanilla:
sama2… semoga infonya berguna hehe…..
edwinsetiawan
June 13, 2009 at 4:55 pm
berarti kalo total dof 0.04, artinya object in focus cuman yang di 0.04 itu…so kalo matanya ga sejajar / frontal facing, the other eye will be out of focus karna uda lwat dari 0.04 ya…
lets see….nikon 85 f1.4 body d700
hasilnya @ f1.4 distance 5m
near limit 4.86
far limit 5.15
total 0.29
artinya minimal object yang mau di bikin focus musti ada di range 4.86 (paling deket) sampe 5.15 (paling jauh) ya? lewat dari 5.15 atau kurang dari 4.86 itu blur area kan?
martien
June 14, 2009 at 2:55 am
[...] Original post: How to Use Maximum Aperture Effectively ? « Just about Photography [...]
How to Use Maximum Aperture Effectively ? « Just about Photography
June 14, 2009 at 7:26 am
@martien:
yoi…. sip klo dah ngerti hehe….
edwinsetiawan
June 14, 2009 at 8:17 am
thanks bro! saatnya main2 ama lens baru nih hehehe…
martien
June 15, 2009 at 6:06 am
your welcome….
edwinsetiawan
June 15, 2009 at 11:45 am
everything’s clear, thank you!
Denys Zaikin
June 28, 2009 at 4:10 pm