[photolady95]

Autofocus to manual focus. Is there any way to change an AF lens and make it MF only?

And I'm not talking about setting the camera up that way. I know how to do that.

[jpzk]

Autofocus to manual focus. Is there any way to change an AF lens and make it MF only?

And I'm not talking about setting the camera up that way. I know how to do that.

I thought this was indeed an odd question ...
Can you not just switch the AF to OFF on camera and do the same with the AF lens ... ? Or you just wanted to take the entire AF mechanism off of the lens?
Just curious!

Edit: ... Sorry, just saw this: "And I'm not talking about setting the camera up that way. I know how to do that."

[jatrax]

I suppose the short answer is yes but it would require surgery that might/might not be reversible. For an SDM lens I suppose cutting the leads or removing the contacts would make it MF only. Note that some SDM lenses actually have a AF/MF switch on the lens.

For a screwdrive lens, you could remove as much of the screwdrive shaft as possible, either by removing parts (reversible) or cutting off the part that engages with the camera drive (probably not reversible).

You could also trade me your AF lens for the MF equivalent from my collection. But I would have to see what you are trading first.

Curious where this train of thought came from?

[MarkJerling]

Many AF lenses do not have the nice fine manual focus focus ring movement that manual focus lenses do. So, often MF with an AF lens can feel less precise.
The easiest fix is the switch on the camera body. But I'm curious - Why?

[Nass]

Maybe have a go at identifying which of the contacts transmits focus information, and tape over just that one?

[pakinjapan]

Autofocus to manual focus. Is there any way to change an AF lens and make it MF only?

And I'm not talking about setting the camera up that way. I know how to do that.

yeah, it is an odd question. what about tape out / cover the screw part of the lens? anyway, switch to manual focus mode on your camera [which you already know] seems to be the best way to go.

[Pentax Syntax]

Some lenses like the 28-70 2.8 FA* and 80-200 FA* and a few others have a clutch that renders them manual focus. It is a nice feature to have since you can use the catch in focus (trap focus) setting and a few other tricks. Looking over your equipment list, I did not notice any of the lenses with this feature.

[stevebrot]

For screw drive lenses, you can simply tape over the "data" contact, though you must also flip the switch on the body to "off" to ensure that the the drive pawl is disengaged. The drive pawl must be disengaged to avoid damage to the AF drive in the body.

For motor-in-lens AF the data contact should be taped along with the two power contacts. All three are used in the AF control protocol with those lenses.


Steve

[stevebrot]

The suspense is killing me...what is the use case?


Steve

[photolady95]

Okay, here is the reason why. I have several AF Sigma lenses. I have as you can see in my signature a Sigma 400mm prime that has stopped autofocusing (a broken gear I was told), and it has no switch to change it. I have two other sigma zooms that I'd like to change to manual focus only and neither of them has a switch for AF/MF.

I have been using a Vivitar M 200mm with CIF. I would like to be able to use other lenses this way but since the other lenses are AF, I can't do that.

The switch on the camera is not the fix. Because in CIF you have to have the camera set to AF.S. And as you know, that would make the AF lens, AF.

I would really like just the Sigma 400mm changed.
Taping sounds reasonable, but how would I find which contact I would need to tape over?

You could also trade me your AF lens for the MF equivalent from my collection. But I would have to see what you are trading first.

You're so funny!

[D1N0]

Some older Pentax SDM lenses have that feature built in. Problem is you never know when it is going to be activated.

[wombat2go]

The old Pentax ist ds and the Pentax K-01, can be set to "MF" with a DA lens.
In M mode, the ist ds will give VF flash of manual focus confirmation, and the K-01 will allow the manual contrast focus.
Both cameras will then allow an exposure.
Are the present Pentax models inhibiting this functionality?

[jatrax]

with CIF. I would like to be able to use other lenses this way but since the other lenses are AF, I can't do that.

I really did not think you were going to come up with a good use case. But you did. One of the things I liked about the DA*16-50 was the switch on the lens to make it MF, then you could use CIF with it.

I have all my gear set up for back button focus and (as far as I know) that eliminates CIF so I had not even thought of it. I really like the idea of CIF, just not willing to give up back button focus for it.

[photolady95]

The old Pentax ist ds and the Pentax K-01, can be set to "MF" with a DA lens. In M mode, the ist ds will give VF flash of manual focus confirmation, and the K-01 will allow the manual contrast focus. Both cameras will then allow an exposure. Are the present Pentax models inhibiting this functionality?

Ever camera I own, (listed in my signature) can be set as MF with the switch on MF and any AF lens but this is not what I'm talking about. jatrax gets it.

[photolady95]

Question, what is back button focus?

My biggest problem is, most of my AF lenses are not sharp at their long end, so I back them off and couple with either a 1.4x TC or 1.7x TC I still get the reach I need but even at 250/200mm things are not in focus like when I use CIF. That's why I use the Vivitar 200mm M lens most often for birding.