For portraits on a Sony a77, which gives shallower depth of field: 50mm f/1.7 or 70-210mm f/4?
Asked 2/15/2016
37 views
2 answers
0
I’m shooting portraits with a Sony a77 and comparing two Minolta lenses: a 50mm f/1.7 used wide open, and a 70-210mm f/4 used wide open. Which setup will give me the shallower depth of field for portraits?
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
10y ago
2 Answers
5
Depth of field calculation depends on multiple factors:
- captor size
- focal length
- aperture
- and last but not least: subject distance
Using a Depth of field simulator (http://www.dofmaster.com/dofjs.html) with your camera, you will get the following result:
Distance to subject: 5 meters
- 50mm f/1.7 => Depth of Field of 0.67 m
- 70 mm f/4 => Depth of Field of 0.81 m
- 150 mm f/4 => Depth of Field of 0.17 m
- 210mm f/4 => Depth of Field of 0.09 m
Distance to subject: 10 meters
- 50mm f/1.7 => Depth of Field of 2.73 m
- 70 mm f/4 => Depth of Field of 3.3 m
- 150 mm f/4 => Depth of Field of 0.70 m
- 210mm f/4 => Depth of Field of 0.36 m
I suggest you try the simulator with your conditions. You might want to take a look at those questions :
Originally by user26456. Source · Licensed CC BY-SA 4.0
user26456
10y ago
0
Generated from our catalog & community — verify before relying on it.
It depends on subject distance and which focal length you use on the 70-210mm.
Depth of field is affected by sensor size, focal length, aperture, and distance to the subject. On your Sony a77, if you compare at the same subject distance:
- 50mm at f/1.7 gives shallower depth of field than 70mm at f/4
- But the 70-210mm at the longer end (especially 150-210mm at f/4) can give much shallower depth of field than the 50mm
Example figures from a DOF calculator at 5m:
- 50mm f/1.7: about 0.67m DOF
- 70mm f/4: about 0.81m DOF
- 150mm f/4: about 0.17m DOF
- 210mm f/4: about 0.09m DOF
So for portraits, the 50/1.7 is shallower than the zoom only at the zoom’s shorter end. At the telephoto end, the 70-210/4 will blur the background more.
Also note that 50mm f/1.7 can produce a very thin plane of focus, which may be too shallow for some portraits. A depth-of-field calculator is the best way to compare for your actual shooting distance.
Recommended products
UniqueBot
AI10y ago
Your Answer
Related Questions
Which gives shallower depth of field for the same framing: 50mm f/1.4 or 85mm f/1.8?
How do I use the focus distance/depth-of-field scale on a Pentax 50mm f/1.7 when shooting for bokeh?
Which lens gives more background blur on a Sony a6500: 30mm f/1.4, 50mm f/1.8, or 56mm f/1.4?
Which current camera bodies can use Minolta AF 50mm and 70-210mm lenses?
Can Minolta A/Maxxum AF lenses be adapted to a Canon EOS Rebel T2i/550D?