Jump to content

Recommended Posts

I have a couple of older Olympus OM lenses and want to use them on my A7R2.  The 21mm f3.5 works fine and is a remarkabaly sharp quality lens.  The adapter marked OM-NEX is a low priced one acquired on eBay for about $11 (USD).  The problem I encountered is that when I use the adapter with the 300mm f4.5 Olympus OM lens, I cannot focus at infinity.  IMHO, the adapter is a bit too long for use with a 300mm lens and thus the lens set at the infinity mark, is still out of focus on a very distant object. Has anyone had this issue with long lenses?  Is there modestly priced adapter that is at precisely correct length and permits focus at infinity?

Link to post
Share on other sites

`     

   

You observations present the opposite of the facts 

of optical life. Wide angle lenses are extremely 

vulnerable to tiny differences in physical distance 

from the image receptor.  

   

Without doubting your observations, there are a 

few rational conclusions. 

  

A. Your adapter is too long, much too long, cuz it 

takes a serious does of over-length to effect such 

lenses as a 300mm .... BUT if indeed the adapter

is much too long your wide lens focuses waaaay 

past infinity, compensating that over length. This 

rationale follows the physical rules, but OTOH is  

a highly unlikely scenario in the real world. 

   

B. Your 300 is defective. Also unlikely.  

   

C. The DoF of your wide angle may be hiding a 

lack of real infinity focus. But I'd be surprised if 

it can hide the amount amount of overlength-of-

adapter that can noticably wreck infinity focus of 

a 300mm lens.  

    

Cheap adapters are intentionally blueprinted to 

anticipate slightly sloppy machining. IOW they 

are blueprinted to be decidedly SHORT of ideal 

length, so that lenses on them will always focus 

[to varying degrees] well beyond infinity position

which is a very usable result for $10 to $35, that

results in no user complaints at such low pricing.   

    

While NOT doubting your observations for sake

of "conversation" [above], given the real laws of

physics, a solution most likely does require that 

we doubt some detail of your observations :-(   

  

It's only natural to suspect the adapter cuz it's 

so cheap, but your problem, as described, just

makes no sense. 

Link to post
Share on other sites

  • 2 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Posts

    • I don't know much about this camera but here is a link to comprehensive specifications: Sony ZV 1F Specifications It doesn't mention a wired controller. It doesn't have a 2.5mm socket but I believe that you could use the USB C port to connect a remote.
    • Hi. tried this one. I have the same problem and read your post. I tried everything until this. it worked.   LuckySn0wMan •4mo ago•Edited 4mo ago   I've just had exactly this issue recently on my Sony A7r2 and successfully resolved it. I bought this camera used, so looks like the previous owner of the camera tweaked it's firmware to unlock additional languages. These tweaks caused this issue after the camera spent significant amount of time without the battery installed. Note that on ny camera the OpenMemories tweak app is not installed, so I used the pmca-gui PC application to change tweak settings of the camera firmware without the OpenMemories in camera app. So my sequence of actions to fix the camera: Install the battery. Connect the camera via micro-usb cable to your windows bases PC. Power on the camera. It should start in mass storage mode. Download the pmca-gui-v0.18-win.exe executable from the official github page: https://github.com/ma1co/Sony-PMCA-RE/releases. On the Camera info tab press the Get camera info button just to test that the app can successfully detect the camera. Go to the Tweaks tab. Press the Start tweaking (updater mode) button. The Updater mode tweaks tab should popup. Camera display will be completely black and the buttom right LED will be on. Select the Unlock protected setting checkbox. Uncheck the Unlock all languages checkbox. Uncheck the Unlock protected setting checkbox. Press the Done button. Once the app applies all changes to the camera firmware, exit from the app and power off the camera. After power on the camera should start working as usual. As additional info: My camera had the following tweak settings during the gray screen problem: Disable video recording limit: not selected Unlock all languages: selected (possible cause of the bug) Enable PAL/NTSC selector & warning: selected Enable USB app installer: not selected Unlock protected settings: selected After my changes that helped to fix the camera power on gray screen: Not selected Not selected Selected Not selected Not selected
    • I'm considering purchasing a Sony ZV 1F camera and have a couple of questions, answers to that either don't exist in the specifications or are not clear. I particularly interested in the video features of this camera. 1. does it have a wired remote control? If it does, does it use a 2.5mm ring tip and sleeve connector? 2. It's a 4K camera, what are the actual recording image sizes and FPS that it supports? I'm ex Canon and looking to convert to Sony. Regards Peter Resch
  • Topics

×
×
  • Create New...