Wish there were more SSM lenses...Im done with screw drive

Ive had heaps and heaps of the Minolta primes and zooms - and love the optics. The 50mm 1.4 is one of my favs. But im done. The focus is just too inaccurate and unreliable. Id rather have the Minolta 50mm than my Zeiss 50mm, but the focus just sucks in comparison.

Really wish that Sony updated these to SSM

Rant over.

[No message]

a99.

To be clear, its not a MFA issue. Its the fact that crew drive lacks sufficient 'resolution' or finesse, particularly up close at wide apertures.

Well, this doesn't reflect my experience over the years.

What comes to my mind first is simply the noise of screw driven focussing. On second place perhaps speed, especially when focussing components are heavier in bigger lenses.

Focussing speed / accuracy is two-way-dependant between "command" coming from the cam's AF system and the "execution" by the cam's AF motor - the screw driven lens only as a passive element.

Yeah perhaps a differently geared mechanics with more rotation like we find usually in macro lenses might increase accuracy - but usually at the cost of speed.

I don't think that going SSM is the universal answer. Sony's A-Mount 2,8/70-200 SSM Mk1 was hardly any better (faster) than older Minolta versions still screw driven. They were silent focussing though. Real speed and accuracy gains only in more recent SSM generations based on two linear motors - but also coupled to distinct AF systems than used on A-Mount.

Maybe set your camera up for back button focus and use continuous focus. Just a thought.

floyd_of_oz said:

Ive had heaps and heaps of the Minolta primes and zooms - and love the optics. The 50mm 1.4 is one of my favs. But im done. The focus is just too inaccurate and unreliable. Id rather have the Minolta 50mm than my Zeiss 50mm, but the focus just sucks in comparison.
Really wish that Sony updated these to SSM

Rant over.

Click to expand...

Not noticed this issue and I shoot, amongst other lenses, the Minolta 80-200 f2.8 HS and Sony CZ 135mm f1.8, both of which feature screw drive and both of which have very narrow depth of field when shot wide open. Not an issue on my a99 or a99ii and have used for both static and moving subjects in both AF-S and AF-C. I'm not sure there is any technical reason why screw drive is inherently less accurate than SSM as a focus technology.

I have many screw drive lenses and several SSM lenses. The SSM lenses are quieter but I don't find the autofocus on them to be quicker or more accurate than that on my similar quality screw drive lenses. In fact most of my favourites are screw drive - Minolta 200/2.8, Sony 135/1.8/ZA and Minolta 85/1.4. Admittedly the latter is slower but the accuracy is fine. And that's been the case on A99 and A99ii.

Thanks for the input everyone, interesting experiences to read about.

For me, shooting my young daughter with the Minolta 50mm 1.4 results in about 10% of my images having the focus actually where I wanted it and placed it while shooting - while the Sony Zeiss 50mm gets me about 90% hit rate.

floyd_of_oz said:

Thanks for the input everyone, interesting experiences to read about.

For me, shooting my young daughter with the Minolta 50mm 1.4 results in about 10% of my images having the focus actually where I wanted it and placed it while shooting - while the Sony Zeiss 50mm gets me about 90% hit rate.

Click to expand...

I'm assuming you shoot wide open, the 50/1.4 suffers from veiling haze, meaning the af might face some issues to get proper focus with low contrast subjects. To avoid such shifts in critical focus try using the lens closed down a stop or two.

While the camera focus wide open, the wider DOF will compensate.

Lenses that have good af results in my experience on a A900 and A99ii M200/2.8 M80-200/2.8 CZ135/1.8 CZ85/1.4 M85.14 M135/2.8

The spherical aberration causes issues for phase-detect focusing. The AF sensors see a somewhat stopped down image and the actual aperture is held open during focusing.

I've also seen the mechanical lash in screw-drive allow the focus to shift when the aperture is activated. Unfortunately, Sony doesn't offer fixed stopped down aperture operation for A-mount lenses.

IMO, the problem with the screw drive F1.4 is that it has a focus shift at F1.8(or F2).

The camera always focuses wide open, so you can only calibrate MFA for one situation (at least on my A99). So basically, I could have tack sharp focus for F2-F22.... or I could have tack sharp focus on F1.4.

The people at the Sony store were nice enough to swap lenses with their display lens. And even then... same issue. I really miss the Sony Store.

Also, I have the Zeiss SSM 50mm F1.4. Its one of my favorite lenses. I am surprised that you like the screw drive F1.4 better, as it was one of my least favorite lenses. I liked the 50mm F1.7 minolta, much more than the screw drive 50mm F1.4.

Or should I say, in my humble experience?

The four screw drives in my collection are:

• beercan
• Minolta 35/1.4G
• Minolta 85/1.4G
• Zeiss 135/1.8

With my a99ii, I have no problems with AF-S. AF-C does not work so well with the 85, but it focuses a little slow due to all the mass moving (I assume). Otherwise, I have always been quite pleased with the other three, in particular wide open in dark situations.

Of note: I am now using an E mount a7Rv with the LA-EA5 adapter. The 85 still struggles with some of the advanced AF features, but I can still get good results with AF-S, even well outside the center. The other three work very well, better than on my a99ii. I've been quite impressed with the 35, it's like the ol' dog learned new tricks!

tqlla said:

IMO, the problem with the screw drive F1.4 is that it has a focus shift at F1.8(or F2).

Click to expand...

Focus shift usually refers to a change in focus that occurs with changes in aperture even when using MF. I don't see that with mine (although it has plenty of other shortcomings). All manually focused wide open on the '9' mark:











Is there a different test that would show it?

tqlla said:

The camera always focuses wide open, so you can only calibrate MFA for one situation (at least on my A99). So basically, I could have tack sharp focus for F2-F22.... or I could have tack sharp focus on F1.4.

Click to expand...

That's AF adjustment. Did you also see the effect when using MF?

I'm not seeing a shift even when using AF here and forcing refocusing between shots:

Maxxuman said:

I have many screw drive lenses and several SSM lenses. The SSM lenses are quieter but I don't find the autofocus on them to be quicker or more accurate than that on my similar quality screw drive lenses. In fact most of my favourites are screw drive - Minolta 200/2.8, Sony 135/1.8/ZA and Minolta 85/1.4. Admittedly the latter is slower but the accuracy is fine. And that's been the case on A99 and A99ii.

Click to expand...

Hey there,

I have been shooting with the Sony 70-300 and 70-400 ssm lately and I must say that those are faster than my older Minolta (none of them are HS).

The real deal is "Is this relevant for my photography" ? When I shoot surfers or trackday cars I definitely can say that ssm focusing is the winner (obviously noise is not even a criteria for those scenario). If shooting anything else of my usual subject, I just couldn't care less actually.

So the big question is "Does it matter for what I shoot" ? If no, then if one can find a good 2nd hand ssm for a nice price, go for it, otherwise a Minolta HS will do the job.

ActionPhotoPassion said:

Maxxuman said:

I have many screw drive lenses and several SSM lenses. The SSM lenses are quieter but I don't find the autofocus on them to be quicker or more accurate than that on my similar quality screw drive lenses. In fact most of my favourites are screw drive - Minolta 200/2.8, Sony 135/1.8/ZA and Minolta 85/1.4. Admittedly the latter is slower but the accuracy is fine. And that's been the case on A99 and A99ii.

Click to expand...

Hey there,

I have been shooting with the Sony 70-300 and 70-400 ssm lately and I must say that those are faster than my older Minolta (none of them are HS).

The real deal is "Is this relevant for my photography" ? When I shoot surfers or trackday cars I definitely can say that ssm focusing is the winner (obviously noise is not even a criteria for those scenario). If shooting anything else of my usual subject, I just couldn't care less actually.

So the big question is "Does it matter for what I shoot" ? If no, then if one can find a good 2nd hand ssm for a nice price, go for it, otherwise a Minolta HS will do the job.

Click to expand...

As I said earlier, the original question was about AF accuracy. There is no inherent reason why for static objects and AF-S, screw drive will be any less accurate than an SSM system. Where SSM pulls ahead is in terms of moving targets shot using AF-C, AF tracking, and overall speed of acquisition.

You mention the Minolta "HS" lenses. Those lenses in general are as fast as SSM motors, but are noisy, create a lot of torque, which may or may not be a good thing for the camera body - you can feel the torque as you hold the body - and perform a bit worse than SSM lenses with AF-C and tracking but not as bad as regular screw drive.

BTW, you can't have your cake and eat it - while SSM lenses are quiet and fast, there is a tendency for them to fail and need repair more than screw drive lenses - repair centres will tell you that blown SSM motors are quite common, and the issue now with Minolta or Sony a-mount SSM lenses is that it's dubious as to whether spares exist for some of these lenses anymore. Not to mention the fact that Sony a-mount bodies have an SSM fuse soldered to the PCB and that has been known to fail, rendering all SSM lenses non-functional on affected bodies. You don't run any such risk using screw drive lenses on a-mount cameras as obviously that does not make use of the SSM fuse on the body.

--
https://www.flickr.com/photos/marcoc/
"When words become unclear, I shall focus with photographs. When images become inadequate, I shall be content with silence." Ansel Adams.

Marco Cinnirella said:

ActionPhotoPassion said:

Maxxuman said:

I have many screw drive lenses and several SSM lenses. The SSM lenses are quieter but I don't find the autofocus on them to be quicker or more accurate than that on my similar quality screw drive lenses. In fact most of my favourites are screw drive - Minolta 200/2.8, Sony 135/1.8/ZA and Minolta 85/1.4. Admittedly the latter is slower but the accuracy is fine. And that's been the case on A99 and A99ii.

Click to expand...

Hey there,

I have been shooting with the Sony 70-300 and 70-400 ssm lately and I must say that those are faster than my older Minolta (none of them are HS).

The real deal is "Is this relevant for my photography" ? When I shoot surfers or trackday cars I definitely can say that ssm focusing is the winner (obviously noise is not even a criteria for those scenario). If shooting anything else of my usual subject, I just couldn't care less actually.

So the big question is "Does it matter for what I shoot" ? If no, then if one can find a good 2nd hand ssm for a nice price, go for it, otherwise a Minolta HS will do the job.

Click to expand...

As I said earlier, the original question was about AF accuracy. There is no inherent reason why for static objects and AF-S, screw drive will be any less accurate than an SSM system. Where SSM pulls ahead is in terms of moving targets shot using AF-C, AF tracking, and overall speed of acquisition.

You mention the Minolta "HS" lenses. Those lenses in general are as fast as SSM motors, but are noisy, create a lot of torque, which may or may not be a good thing for the camera body - you can feel the torque as you hold the body - and perform a bit worse than SSM lenses with AF-C and tracking but not as bad as regular screw drive.

BTW, you can't have your cake and eat it - while SSM lenses are quiet and fast, there is a tendency for them to fail and need repair more than screw drive lenses - repair centres will tell you that blown SSM motors are quite common, and the issue now with Minolta or Sony a-mount SSM lenses is that it's dubious as to whether spares exist for some of these lenses anymore. Not to mention the fact that Sony a-mount bodies have an SSM fuse soldered to the PCB and that has been known to fail, rendering all SSM lenses non-functional on affected bodies. You don't run any such risk using screw drive lenses on a-mount cameras as obviously that does not make use of the SSM fuse on the body.

Click to expand...

Agreed. SSM or screw driven can show some AF-ing being off even if the AF is confirmed in view finder. I just expressed the fact in my experience that all my ssm lenses were quicker at AFing + tracking than my current Minolta lineup for action shots.

And I would add that it's needed to have a Minolta HS lens to feel the torque as I experienced that with Mino beercan 70-210/4 and beercan 28-135.

It's a shame that the SSM system could fail at any point either in-lens or in-body (which is the worst case scenario here) because as you mentioned Sony isn't providing any repair support nowadays.

sybersitizen said:

tqlla said:

IMO, the problem with the screw drive F1.4 is that it has a focus shift at F1.8(or F2).

Click to expand...

Focus shift usually refers to a change in focus that occurs with changes in aperture even when using MF. I don't see that with mine (although it has plenty of other shortcomings). All manually focused wide open on the '9' mark:

Is there a different test that would show it?

sybersitizen said:

The camera always focuses wide open, so you can only calibrate MFA for one situation (at least on my A99). So basically, I could have tack sharp focus for F2-F22.... or I could have tack sharp focus on F1.4.

Click to expand...

That's AF adjustment. Did you also see the effect when using MF?

I'm not seeing a shift even when using AF here and forcing refocusing between shots:

Click to expand...

I rarely ever use manual focus. Try using AF-S, center point. Compare F1.4 to F2.8.

I dont have an A99 or that F1.4 lens to compare to any more.

tqlla said:

sybersitizen said:

tqlla said:

IMO, the problem with the screw drive F1.4 is that it has a focus shift at F1.8(or F2).

Click to expand...

Focus shift usually refers to a change in focus that occurs with changes in aperture even when using MF. I don't see that with mine (although it has plenty of other shortcomings). All manually focused wide open on the '9' mark:

Is there a different test that would show it?

tqlla said:

The camera always focuses wide open, so you can only calibrate MFA for one situation (at least on my A99). So basically, I could have tack sharp focus for F2-F22.... or I could have tack sharp focus on F1.4.

Click to expand...

That's AF adjustment. Did you also see the effect when using MF?

I'm not seeing a shift even when using AF here and forcing refocusing between shots:

Click to expand...

I rarely ever use manual focus. Try using AF-S, center point. Compare F1.4 to F2.8.

Click to expand...

I compared f/1.4 to f/2.2 using AF-S in the last two shots. All my tests were with the center point, which is the only one I really use.

What I see with mine is more like what QuietOC commented on earlier: The AF lock is not really on the distance represented by what's in the center AF square. Instead, the focus locks on a slightly shorter distance, and that happens even when AF Micro Adjust is set to the maximum of +20. The effect does change as the lens is stopped down, although that's probably at least in part because DOF is always deeper beyond the point of best focus.

tqlla said:

I dont have an A99 or that F1.4 lens to compare to any more.

Click to expand...

Sony A7RV in APS-C mode, LA-EA5, Minolta [screw focus] 200 HS APO; @ F:4, 1/320, ISO 125—entire frame.




Same, at ±400% magnification.

Kids,

I can't pretend to know anything about anything, but here is a frame I took yesterday. A7RV in APS-C mode, with LA-EA5 and Minolta 200/2.8 HS APO [screw]; @ F:4, 1/320, ISO 125. Inset of eye is approximately 400% magnification. To this older gentleman, image looks semi-sharp!

Best to all.

Jacques Vroom

jacquesvroom said:

Sony A7RV in APS-C mode, LA-EA5, Minolta [screw focus] 200 HS APO; @ F:4, 1/320, ISO 125—entire frame.


Same, at ±400% magnification.

Kids,

I can't pretend to know anything about anything, but here is a frame I took yesterday. A7RV in APS-C mode, with LA-EA5 and Minolta 200/2.8 HS APO [screw]; @ F:4, 1/320, ISO 125. Inset of eye is approximately 400% magnification. To this older gentleman, image looks semi-sharp!

Best to all.

Jacques Vroom

Click to expand...

"...semi sharp" Love the sarcasm - that lens is phenomenal, as is my 80-200 Minolta HS - love these "built like a tank" old Minoltas

--
"When words become unclear, I shall focus with photographs. When images become inadequate, I shall be content with silence." Ansel Adams.