Determining infinity focus

Determining infinity focus

I purchased a new lens which arrived today, a manual focus Rockinon 12mm f/2.0 for use on my Sony a6000. I’ve read comments on this lens suggesting that sometimes the infinity focus isn’t marked in the right spot on the lens barrel. What would be the best way to test and determine where infinity focus should be set on this lens? One suggestion I’ve come across is to focus on the moon at night - seems pretty easy if so. Thanks for any suggestions!

Hey Chris, welcome to NPN! What I’ve found over the years is infinity is not necessarily what you need for night photography, you instead need hyperfocal which is slightly off infinity. I have an old article about this here the images are broken (need to fix that) but it’s mostly in the text anyways. It’s best to use live view and not rely on the lens markings so much.

Now, I will say that I have that lens for my Fuji and really dislike it. I have not been able to get a sharp shot with it at night, I’ve heard this from a number of others as well. I quit using and don’t recommend it for anyone I’m sorry to say. I hope you have better luck!

Thanks for the reply David, astrophotography and night photography aren’t my applications but I appreciate your suggestions regarding hyperfocal distances, One of the challenges of this lens is that it doesn’t have a focus scale which somewhat complicates this but I think hyperfocal data can be determined ahead of time. My concern is that there appears to be a range of where infinity focus is achieved as the marker is samyang/rokinon’s L shaped indicator.