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Sony LA-EA4 Micro Adjust tidbit
Jan 16, 2021 20:58:04   #
a6k Loc: Detroit & Sanibel
 
As one helpful Hogger pointed out to me, the distance from the subject makes a difference in the precision of the AF. This is a quick report on my further experience testing the idea. Perhaps there is someone else out there using this adapter. I am offering this information in the hope it may be helpful.

I don't really understand why, in this case (fixed length, fixed aperture) but it's something I was able to test. At close distance, a -2 was the best I could do but at over 30' then -1 was the best. These are not large differences but I am now convinced they are real. I am using the adapter for a Minolta 500/8 AF Reflex lens. The result at over 30' appears to be the same as 500', BTW.

Sony simply says that the adjustment should be tested under shooting conditions. Considering the case, that's a lot easier said than done. That lens is HARD TO USE so testing micro adjustments in the field is close to impossible.

Testing this is difficult because a 500 mm lens is very twitchy and the DOF is very thin. I don't have a tripod with me.

Empirical beats theoretical every time.

The reason this needs to be done is the same as for a DSLR. The AF in both cases is using something other than the sensor itself so the mechanism can be imperfectly matching what the sensor will see. Mirrorless doesn't need this. My Sony is mirrorless but the adapter is using a translucent mirror and essentially the same concept as a DSLR. The new LA-EA5 will not have this problem nor doe the LA-EA3 since it has no internal mirror and is not AF anyhow.

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Jan 16, 2021 21:31:01   #
BassmanBruce Loc: Middle of the Mitten
 
I bought the LA-EA5 with high hopes but it did not function with any of my a mount lenses (mostly Minolta maxxum) on my A7r iii. I returned it.
Don’t mean to be a downer or hijack thread, but hope this might help some folks.
Research prior to purchase indicated it would work with these.
Included was Ken Rockwell who I thought indicated he had used it successfully on all his maxxum lenses.
His review has been changed to indicate it only works thusly on the A7r iv. (And maybe the A9 ii?)

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Jan 16, 2021 21:47:44   #
User ID
 
a6k wrote:
As one helpful Hogger pointed out to me, the distance from the subject makes a difference in the precision of the AF. This is a quick report on my further experience testing the idea. Perhaps there is someone else out there using this adapter. I am offering this information in the hope it may be helpful.

I don't really understand why, in this case (fixed length, fixed aperture) but it's something I was able to test. At close distance, a -2 was the best I could do but at over 30' then -1 was the best. These are not large differences but I am now convinced they are real. I am using the adapter for a Minolta 500/8 AF Reflex lens. The result at over 30' appears to be the same as 500', BTW.

Sony simply says that the adjustment should be tested under shooting conditions. Considering the case, that's a lot easier said than done. That lens is HARD TO USE so testing micro adjustments in the field is close to impossible.

Testing this is difficult because a 500 mm lens is very twitchy and the DOF is very thin. I don't have a tripod with me.

Empirical beats theoretical every time.

The reason this needs to be done is the same as for a DSLR. The AF in both cases is using something other than the sensor itself so the mechanism can be imperfectly matching what the sensor will see. Mirrorless doesn't need this. My Sony is mirrorless but the adapter is using a translucent mirror and essentially the same concept as a DSLR. The new LA-EA5 will not have this problem nor doe the LA-EA3 since it has no internal mirror and is not AF anyhow.
As one helpful Hogger pointed out to me, the dista... (show quote)


The LAEA3 is autofocus. It’s for in-lens AF motors.

If you are testing and tweaking your 500 without a tripod you must be a masochist :-(

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Jan 17, 2021 08:09:47   #
FalconChase Loc: Canton,Ohio, USA
 
a6k wrote:
As one helpful Hogger pointed out to me, the distance from the subject makes a difference in the precision of the AF. This is a quick report on my further experience testing the idea. Perhaps there is someone else out there using this adapter. I am offering this information in the hope it may be helpful.

I don't really understand why, in this case (fixed length, fixed aperture) but it's something I was able to test. At close distance, a -2 was the best I could do but at over 30' then -1 was the best. These are not large differences but I am now convinced they are real. I am using the adapter for a Minolta 500/8 AF Reflex lens. The result at over 30' appears to be the same as 500', BTW.

Sony simply says that the adjustment should be tested under shooting conditions. Considering the case, that's a lot easier said than done. That lens is HARD TO USE so testing micro adjustments in the field is close to impossible.

Testing this is difficult because a 500 mm lens is very twitchy and the DOF is very thin. I don't have a tripod with me.

Empirical beats theoretical every time.

The reason this needs to be done is the same as for a DSLR. The AF in both cases is using something other than the sensor itself so the mechanism can be imperfectly matching what the sensor will see. Mirrorless doesn't need this. My Sony is mirrorless but the adapter is using a translucent mirror and essentially the same concept as a DSLR. The new LA-EA5 will not have this problem nor doe the LA-EA3 since it has no internal mirror and is not AF anyhow.
As one helpful Hogger pointed out to me, the dista... (show quote)


I have this adapter and have only had to adjust for one lens, the Minolta 70-210 f4 "beer can". A setting of -5 works for me, and is good for the full range of the lens.

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Jan 17, 2021 08:11:00   #
FalconChase Loc: Canton,Ohio, USA
 
BassmanBruce wrote:
I bought the LA-EA5 with high hopes but it did not function with any of my a mount lenses (mostly Minolta maxxum) on my A7r iii. I returned it.
Don’t mean to be a downer or hijack thread, but hope this might help some folks.
Research prior to purchase indicated it would work with these.
Included was Ken Rockwell who I thought indicated he had used it successfully on all his maxxum lenses.
His review has been changed to indicate it only works thusly on the A7r iv. (And maybe the A9 ii?)
I bought the LA-EA5 with high hopes but it did not... (show quote)


It also works on the a6600.

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Jan 17, 2021 08:14:04   #
tcthome Loc: NJ
 
I'm curious, Does Sony offer this kind of service like Nikon does & I imagine Canon does? Just wondering, from time to time I think of buying in to the Sony system. Thanks for any replies in advance.

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Jan 17, 2021 10:46:40   #
a6k Loc: Detroit & Sanibel
 
tcthome wrote:
I'm curious, Does Sony offer this kind of service like Nikon does & I imagine Canon does? Just wondering, from time to time I think of buying in to the Sony system. Thanks for any replies in advance.


What kind of service do you mean? This is an adjustment for a single lens copy on a single adapter copy and only applies to the specific lens. Different lenses require different settings and the camera is supposed to remember each (registers the lens).

Just wondering what you are asking, specifically.

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