Automatic vs Manual Focus Lens Comparison with Sony

This post compares two camera lenses, one with auto focus and one manual focus:

• Sony FE 40mm F2.5G G Lens  (SEL40F25G) with autofocus
• Voigtlander 35mm f/2 Ultron VM manual focus lens (M mount)

The camera I used was Sony's A7Cii.

Why use a manual focus lens?

This is the big question I've been asking myself since Sony cameras are praised for their auto focus capabilities. Ultimately, it boiled down to wanting to try a different way of taking photos.

There are a number of drawbacks to shooting with the manual lens I chose:

• no access to auto focus, which includes auto tracking and a myriad of other features
• shutter priority mode (S) is not useful since the camera doesn't have the ability to auto-control the aperture of the lens.
• no meta information about the lens or focal length is saved in the image
• an M-mount to E-mount adapter is required
• and more

Despite the list of drawbacks, I've loved using a manual focus. The way it forces me to compose photos is really fun. Especially if you take photos where there are objects in the foreground (like through a fence), auto-focus can get in your way unless you know what you're doing.

The lens itself has really warm saturated colors. It's smaller in size (though equivalent in weight).

Comparison

I will compare the raw photos unedited except for cropping/rotating, and lens correction. In both cases, I've used a form of aperture priority (A) mode, where the shutter speed and ISO are automatically decided by the camera. This is how I shoot photos rather than manual to control everything to a precise setting.

My hypothesis going into this was that the final edited photos will look the same, but perhaps feel different. That distinction is subtle, but the approach to taking a photo with manual focus requires more focus and intention, which I've learned to enjoy.

Comparison: Takeaways

• the images are more blue on the Sony (cold), more orange on the Voigtlander (warm)
• vignetting is much more prominent with the Voigtlander lens
• colors more more saturated in the Voigtlander lens
• images with the Sony are more balanced, but also flat
• sharpness is about the same
• the Voigtlander feel more vintage without being edited

Comparison: Edited Photos

Comparing images with editing applied (coloring, lighting, etc) it really starts to come down to preference. The Voigtlander images definitely feel warmer, but that could be corrected in post if desired.

So, auto focus or Manual focus?

I think this really comes down to preference, but the main difference is experiential. It's hard to quantify in a side by side comparison.

In my opinion, the final product doesn't vary substantially. Personally I'm enjoying the Voigtlander MF lens, but maybe that's because it's something different and forces me to pay more attention to the process.