Distortion correction with adapted lenses on X-T100???

[markgv]

I recently got the X-T100 and ave been trying out some of my old K-mount (Pentax) glass with an adapter. The pics below were taken with a very fine Tokina SZ-X 80-200, K-mount lens which gets excellent results on my Pentax gear. You will see in the pics that there is significant wavy distortion of what are supposed to be straight line. The first one was taken at ~100mm, the second (of the chimney) at 200mm. Other shots at varying focal lengths come out more or less distorted. I.e., I'm not finding a pattern related to focal length.

Why such distortion? That's not the kind of distortion that easily fixed either.

I got the 15-45 kit lens, and I don't see any issues with it. I think I read somewhere that the X-T100 is applying distortion correction to shots taken with the 15-45. Is the camera trying to apply distortion correction to the adapted lens and hence distorting rather than correcting?

Any help/suggestions are appreciated.

 

[Charles2]

Is the camera trying to apply distortion correction to the adapted lens and hence distorting rather than correcting?

Open the raw file in a developer that does not automatically apply corrections, for example, the donation-only Raw Therapee. If the wavy lines are not there, then the camera put them into the JPG.

 

[Vic Chapman]

LR and PS also have manual distortion correction/control for raw files. Most software will but probably only for raw files.

Vic

 

[markgv]

Open the raw file in a developer that does not automatically apply corrections, for example, the donation-only Raw Therapee. If the wavy lines are not there, then the camera put them into the JPG.

Good idea... Just opened the RAF file in Lightroom. It does not apply corrections (since it can't figure out what lens it is).

Still has the wavy lines...

(I tried Raw Therapee, but it apparently can't read the RAF files and crashed every time I tried to open a RAF.)

 

[markgv]

LR and PS also have manual distortion correction/control for raw files. Most software will but probably only for raw files.

Vic

Yeah, but that's mostly barrel and pincushion distortion. You can see that those wavy lines won't be straightened out in LR.

 

[markgv]

There is a "Mount Adaptor Setting" in the Shooting menu. I just tried using one of the customizable ones and set it to the length I'm shooting at. Still getting very wavy lines.

Under the Mount Adaptor Settings, there are menu options for Distortion Correction, and according to the manual it can be turned off, but I cannot access them. (They show up on the menu screen, but I cannot use the down arrow to get to them.) Odd...

 

[Gavin Stapleton]

There is a "Mount Adaptor Setting" in the Shooting menu. I just tried using one of the customizable ones and set it to the length I'm shooting at. Still getting very wavy lines.

Under the Mount Adaptor Settings, there are menu options for Distortion Correction, and according to the manual it can be turned off, but I cannot access them. (They show up on the menu screen, but I cannot use the down arrow to get to them.) Odd...

Those distortion settings are only for the Leica M adaptor Fujifilm produce.

 

[markgv]

Those distortion settings are only for the Leica M adaptor Fujifilm produce.

That makes sense... Thanks.

Still don't know why I'm getting such crazy distortion. Does not seem to be a problem w/ other lenses, so I don't know why that particular one is an issue. I put it back on my Pentax, and it worked fine.

 

[Charles2]

Open the raw file in a developer that does not automatically apply corrections, for example, the donation-only Raw Therapee. If the wavy lines are not there, then the camera put them into the JPG.

Good idea... Just opened the RAF file in Lightroom. It does not apply corrections (since it can't figure out what lens it is).

Still has the wavy lines...

Then the phenomenon is physics, not firmware. For example, is the adapter a simple mechanical ring, or does it have glass?

(I tried Raw Therapee, but it apparently can't read the RAF files and crashed every time I tried to open a RAF.)

In general RT does open RAF files, so you have run into some glitch.

 

[Peter Jonas]

I recently got the X-T100 and ave been trying out some of my old K-mount (Pentax) glass with an adapter. The pics below were taken with a very fine Tokina SZ-X 80-200, K-mount lens which gets excellent results on my Pentax gear. You will see in the pics that there is significant wavy distortion of what are supposed to be straight line. The first one was taken at ~100mm, the second (of the chimney) at 200mm. Other shots at varying focal lengths come out more or less distorted. I.e., I'm not finding a pattern related to focal length.

Why such distortion? That's not the kind of distortion that easily fixed either.

I got the 15-45 kit lens, and I don't see any issues with it. I think I read somewhere that the X-T100 is applying distortion correction to shots taken with the 15-45. Is the camera trying to apply distortion correction to the adapted lens and hence distorting rather than correcting?

Any help/suggestions are appreciated.

This may well be the result of camera shake while using Electronic shutter with its characteristically slow readout speeds.

It's naturally more severe at longer focal lengths (i.e.: the second image).

Please confirm.

 

[Aoi Usagi]

What type of adapter are you using? Some focal reducers are known to cause some petzval effect.

 

[Advent1sam]

Open the raw file in a developer that does not automatically apply corrections, for example, the donation-only Raw Therapee. If the wavy lines are not there, then the camera put them into the JPG.

Good idea... Just opened the RAF file in Lightroom. It does not apply corrections (since it can't figure out what lens it is).

Still has the wavy lines...

Then the phenomenon is physics, not firmware. For example, is the adapter a simple mechanical ring, or does it have glass?

(I tried Raw Therapee, but it apparently can't read the RAF files and crashed every time I tried to open a RAF.)

In general RT does open RAF files, so you have run into some glitch.

E-Shutter, I am not using it much with x-t100 the mech shutter is reasonably quiet and I have gone off these e-shutters except for static tripod shots generally

 

[markgv]

I have confirmed that it was the electronic shutter that was causing the problem. All's good with the mechanical shutter.

 

[Craig268]

I have confirmed that it was the electronic shutter that was causing the problem. All's good with the mechanical shutter.

Good to hear. The e shutter can produce some fairly wonky unintended effects. I shoot a lot of vintage glass with a simple metal hollow adapter and they all work great.