I am certainly not the first to report that the original Sony a7 has a problem with it’s mount which is loosening over time but so far I haven’t seen an illustration of how this problem can affect image quality.

My Sony a7 arrived on Nov 20. 2013 so it is very close to two years old now. Until now I had noticed that the mount had gotten a little more play over time but it wasn’t a real problem to me.

But now a point is reached were it has become a real issue for me. If I mount a lens like my FE 4/16-35 and pit the camera on a tripod I can see a gap between lens-mount and camera-mount! And the lens also has some rotational play.

Does the problem affect image quality?

Yes it does!

Continue reading The Sony a7’s loosening mount →

The Pentax SMC 4/100 Macro is a small and affordable macro lens from the 70’s. In this review I check if it can still deliver on  today’s 24 Megapixel Sony a7.

Sample Images

f/5.6

Continue reading Review: smc Pentax-M Macro 1:4 100mm →

This blog is mostly about manual lenses which are usually 30 to 50 years old. And while most of them are surprisingly reliable the are a few things you should check before or after buying a lens.

This checklist is based on the experience I gained from buying  more than a hundred lenses since I discovered how much fun it is to use them on Sony’s Alpha cameras.

If you have additional info about a defect not listed or disagree with my assessment please leave a comment!

Scratches on the lenses

Use a large light source like a window and place the lens between you and the light so that you can see the colorful coating of the lens.

Scratches are seldom a problem in the real world but they lower the resale value of a lens. In theory they could reduce the contrast of a lens or cause some flare but I have never seen that happen.

You can’t really do anything to restore coatings but it sometimes makes sense to fill larger scratches with black paint to avoid light scattering.

Continue reading Defects in Manual Lenses and lens buying advice →