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People often ask, why do rangefinder lenses work on sony a7s?
Let’s find out!
Why Do Rangefinder Lenses Work on Sony A7s?
The Sony Alpha 7S is an excellent camera for those who want to get into the world of full-frame photography. It’s not only a good choice if you are looking for an entry-level DSLR, but it also has some very interesting features that make it stand out from other cameras in its class. One of these features is the ability to use rangefinders with your Sony Alpha 7S.
The Sony Alpha 7S is one of the first mirrorless cameras that can be used with a rangefinder lens. This means you can take advantage of the benefits of using a rangefinder without buying a separate adapter or mount.
Problems When Using Rangefinder Wide Angle Lenses on A7 Series Cameras
There are quite significant variations between the different A7 cameras, or, to be precise, between the different sensors inside the A7 cameras. Let’s first review, which issues might arise:
- The edge and corners of the screen may be color casted
- Strong vignetting
- Corner smearing
Color cast and vignetting are mostly influenced by the sensor design and the optical formula of the respective camera. The A7r II is the worst, followed by the A7s (II), then the A7s (I). Wide angles are not affected by these issues.
The camera does not smear the image around the edges of the frame. However, if you shoot at f/2.8 or faster, then the lens may cause vignetting, which can lead to uneven exposure across the frame.
And also somewhat undesirable renderings of the bokeh (blurred background). While in the center of a frame everything is fine, the blurring gets weaker towards the edges. Look at the trees on the left side, where the one near the edge appears less blurred.
Also the same applies to the river on the right side, whereas here the effect becomes even stronger, as the far end of the river is actually closer to the camera. Again, this may only occur at certain focus distance settings. And is less of an issue if the subject is close to the camera.
Why Do Rangefinder Lenses Work On Sony A7S?
Optimal Filter for Certain Lenses
For Plano-Convexes, there are two manufacturers: Opto Sigma from Tokyo, Japan, and Eksma Optical from Vilnius, Lithuania.
The Opto Sigma products have a specific product number (like SLB 50 1500 PM) and an M at the end which indicates that it is coated. You need to contact the distributor who sells them to you.
Delivery times vary depending on where you live. Most of the listed items are made by Opto Sigma.
Most uncoated lenses are in inventory and will be shipped within five business days. If you’d like to coat your lens, we recommend using Coating Number 3217-i0. It takes approximately five weeks for us to receive your order.
Contax G 21mm 2.8 Biogon
Front End Filter: Opto-Sigma SLB-50-1.5M (planoconvex 1.5m). Reversed (the bulbous portion of the glass shows through the lens). Tested.
Infinity focus with TechArt AF adapter is sustained. See the comparison above or this blog.
Voigtlander 25mm 4.0 Snapshot Skopar
Front end filter: Opto Sigma SLB-50-1200PM (plano-convex 1.2m) Tested
To achieve infinity focus for an f/1.4 lens, a shorter focal length adapter and/or the use of a neutral density filter may be required.
Zeiss ZM 25mm 2.8 Biogon
Front end filter: Zeiss Proxar 1m (B57 Ø50mm) Or: Opto Sigma SLB-50-2500PM (plano convex 2.5m) Tested
To achieve infinity focusing for longer focal lengths, a shorter lens adapter and/or the use of shims is required.
Contax G 28mm 2.8 Biogon
Front end filter: Opto Sigma SLB-50-1500PM (plano-convex 1.5m) reversed (bulbous part of the glass element shows to the lens) Tested
With infinity focusing using the TechArt AF Adapter, you can keep shooting for longer periods of time without having to stop and refocus. For further information see this post. And here’s a
Zeiss ZM 28mm 2.8 Biogon
Front end filter: Opto Sigma SLB-50-1500PM (plano-convex 1.5m) Tested
To achieve infinity focus for a short focal length lens, a shorter adapter and/ or the use of shim(s) may be required.
How to Attach a Glass Element to Your Lens?
If you want to get the best results out of your camera, you need to be careful when using filters.You can either buy a set of filters for your camera, or you can attach a filter holder to your existing lens.If you don’t know which one to choose, then we recommend buying a set of filters.
Here is a step-by-step guide that can be used for many lenses.
Contax G 21mm 2.8 Biogon
Attach 55-52mm step-down adapter, put the 1.5m lens into the 52mm thread and clamp it with 52mm ring from AmazonBasics 52mm UV filter (you need a camera spanner to dismantle it).
Contax G 28mm 2.8 Biogon
To attach the 1.5m telephoto zoom to the camera body, use an L-series (1.5m) step-up/step-down ring, which has a 52mm thread. Then, mount the 52mm thread onto the camera body using a
Voigtlander VM 35mm 1.7 Ultron
See ZM 35mm 1.4 and get a 46->55mm Step-Up ring instead.
Conclusion
The front-end lens correction software is fairly new and has its limitations but we think they’re worth considering if you want to use your camera’s full potential. we would love to hear from you if you’ve found something better than the ones listed here.
We hope that this article was helpful. If you have any queries feel free to reach out in the comments section below.
