EMF adapter and focus shift

Orio · Expire: 2012-12-04

This is a topic that deserves a specific thread.
Ok, I managed to learn program the EMF chip. Set focal lenght, set aperture, OK. Setting focus adjust, I start with value 01: panic. Nothing in focus Shocked

Cooled down, made some tests, and finally settled down for value 28, which sets the focus of my Planar 1.4/85 wide open precisely on the beep point. Hurrah! Finally I have a perfect AF chip!.
Now for the death loop test... I set aperture at f/4 and refocus... beep... take photo and enlarge... focus was shifted of at least 1 centimeter forward. Maybe more. Dang. Letdown. Sad

Solution? To buy another EMF adapter, and program it at f/4. And then either swap adapters on the fly, or have a second Planar 1.4/85 at hand with a f/4 focus programmed EMF adapter.
Yep, not really a cheap solution. And sure, you can forget about the AF chips and use liveview... only problem, there are situations where liveview, with it's 1 second blackout between shots, isn't useable.
Oh well. You can't have everything Rolling Eyes

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visualopsins · Expire: 2025-04-11

Is focus confirm different @f/4 depending, focus turned from farther to nearer, and from nearer to farther? My thinking is will be different, that focus confirm @f/4 will be made within dof range, but not at center of dof.

Schnauzer · Expire: 2012-03-08

Orio, I have many of the programmable chipped adapters. On some of them the focus shifted a couple of times at the very beginning while I was adjusting. Turned out it was the way I was adjusting them and using them. They haven't shifted in over a year. They work perfect and I can be sure of a focused shot.

I don't know if you tried this or not, but I always turn my lense to close focus then focus towards infinity to take the shot. You don't have to go close by much, just until you see it isn't sharp then focus towards infinity. You need to do it the same way when adjusting them or you won't get it right. You could go from infinity to close and get the same thing. Always adjust and shoot going one way. This has been my experience in setting them up and using them. If I shoot going opposite the way I adjusted them the shot will be out of focus just about every time. I can even get a shot of the dogs running and have it be in focus about ever time. I think you will be happy with the adapter if you try it this way.

Unless I can't get it in adjustment with the micro-focus I don't adjust the focus of the chip. Out of I think 10 maybe 11 that I have only 4 or 5 needed to be set in the chip.

I just remembered, If I have more than one, say, 50mm I call them 49mm, 50mm and 51 mm. Otherwise when you micro-adjust, the camera will change the micro-adjust to what ever lense you are adjusting at the time since you can only adjust 1 lense per focal length in the camera.

I only use the adapter on the lense I adjusted it for. I don't know how it would be swapping the adapter around.

I hope this is helpful to you.