Should I use a 55mm f/1.8 in crop mode to mimic 85mm, or buy an 85mm f/1.8 for my Sony A7 III?
Asked 7/8/2019
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2 answers
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I shoot casual street photography with a Sony A7 III and currently use a compact 35mm f/2.8. I like the size, but I want more subject isolation and a longer focal length.
Because the A7 III has APS-C crop mode, Iām wondering if a 55mm f/1.8 could do double duty: normal on full frame, and roughly 82ā85mm equivalent in crop mode. That would seem like a flexible way to get another field of view without carrying a separate 85mm lens.
I understand crop mode reduces resolution. My main question is about image look: compared with a real 85mm f/1.8, how close would a 55mm f/1.8 in crop mode be in framing, background blur, and overall usefulness for street and portraits? Would you choose the 55mm for versatility, or the 85mm for better isolation?
Originally by Photography Stack Exchange contributor. Source Ā· Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
7y ago
2 Answers
4
Zeiss 55 1.8 is a very expensive lens.
I believe you could get two used Sigma Art 1.4 lenses to roughly the same price.
If you want to get the shallow depth of field then cropping is not what you want to do.
That translates to a higher aperture value, and makes more in focus.
I have no experience of the Zeiss, but I have two Sigma Art and prior to my last Art purchase I read and looked at lots of reviews on all the focal lengths and they all perform very well as far as I can see from reviews.
The two I got are fantastic in my opinion.
Having two lenses will be bulkier but give you a better aperture value.
Perhaps a good f2 zoom is a good medium way.
But regarding the subject.
I would not crop in camera.
Save it to post where you can crop to what you want and not be "limited" to two crop modes.
Originally by user75423. Source Ā· Licensed CC BY-SA 4.0
user75423
7y ago
0
Generated from our catalog & community ā verify before relying on it.
Crop mode can match the framing fairly closely, but not the look of a true 85mm f/1.8.
A 55mm f/1.8 on your A7 III in APS-C crop gives about an 82ā83mm equivalent field of view, but with less resolution and depth of field closer to an 85mm at about f/2.7āf/2.8. So if your goal is stronger background blur and subject isolation, the real 85mm f/1.8 is the better choice.
If you like the convenience of seeing the cropped composition in the viewfinder, crop mode is usable, but many photographers would rather shoot full frame and crop later for flexibility.
So the tradeoff is simple:
- 55mm f/1.8: more versatile, one lens can cover two framings, but less blur when āsimulatingā 85mm and lower final resolution in crop mode.
- 85mm f/1.8: better subject isolation and the true 85mm look.
If isolation is the priority, get the 85mm. If versatility and carrying fewer lenses matter more, the 55mm plus cropping can work.
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UniqueBot
AI7y ago
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