Mitutoyo 10x e 5x e Sony A7rV

[ChesoLari]

Hi everyone, I purchased two Mitutoyos, one 10x and one 5x.
With Raynox 150 and distance 208, with the 10x I don't see the curvature of the lens on the right side of the image while with the 5x I do.
It's normal?

[Adalbert]

Hi everyone, I purchased two Mitutoyos, one 10x and one 5x.
With Raynox 150 and distance 208, with the 10x I don't see the curvature of the lens on the right side of the image while with the 5x I do.
It's normal?

Yes, Mitu 10x is better for FF

[lothman]

what do you mean by "curvature"? Do you get sharp results with stacked images (what should be the case) or do the corners stay unsharp?

[ChesoLari]

Nel senso che sul lato destro dell’immagine vedo là rotondità dell’obiettivo

[JKT]

Nel senso che sul lato destro dell’immagine vedo là rotondità dell’obiettivo

If that means what I think it does (on one side you see barrell/pincushion distortion and not on the other), something is seriously de-centered. That could be either inside the lens, but it could also be angular error in the setup resulting in optical center being off from the center of the sensor. You could try another stack with the objective rotated 90 or 180 degrees. If the side doesn't change, the problem is in the setup. Doing this in a horizontal setup likely requires shims so that the objective stays aligned with the threads.

[ChesoLari]

Meanwhile, I apologize for the English, as I use Google Translate.

I have to apologize because I had never noticed it but I also have the same problem with the Mitutoyo 10x. Below I post two photos, the first with Mitutoyo 5x and the second 10x. Both original, the 10x purchased new, the second 5x B-Stock

https://ibb.co/4PkvjPW
https://ibb.co/pypZh32

The defect is seen equally with the two lenses, (see the outline of the lens at the top right and bottom right).

At this point I don't think they are defects in the lenses but other problems, perhaps due to the use of a full frame sensor (Sony A7rV)
I enter other data of my configuration: Raynox 150 tube lens, distance lens to sensor 200.4 cm with Nikon PB-6 bellows.

With this distance, without Mitutoyo I have perfect focus at infinity. I calibrated it by framing a castle about 2 kilometers away
I forgot, as suggested, I also tried to rotate the Mitutoyo 90/180 degrees, but nothing changes.

At this point I ask: is this normal? Do I have any defects in my configuration?

I would add that with all my Laowa or Sony lenses, I have never encountered the problem. Thank you all and long live macro photography

[mbf]

Hm, this could be some kind of misalignment somewhere between camera and objective, especially if this is visible with both objectives. So I would not blame the objectives on first sight. If the objective isn't centered along the optical axis, this can happen, even if the objective is able to cover full frame. Or something else blocks the optical pathway... difficult to tell from the distance.

[ChesoLari]

Anyone else using one of these full frame sensor lenses and cameras and experiencing the same problem?

[ChesoLari]

Maybe it can be useful to someone. I did another test this time using the Raynox DCR 150 tube lens system from WeMacro instead of the Nikon PB-6 bellows. In this case no problem, the entire sensor is covered. So in your opinion the problem is that the bellows is not perfectly aligned?

[Darionett]

Maybe it can be useful to someone. I did another test this time using the Raynox DCR 150 tube lens system from WeMacro instead of the Nikon PB-6 bellows. In this case no problem, the entire sensor is covered. So in your opinion the problem is that the bellows is not perfectly aligned?

Ciao Cheso,

Si, sembra che l'obiettivo non sia perfettamente allineato/centrato con il sensore, pertanto non tutta l'area dell'immagine viene proiettata.
Yes, it appears that the lens is not perfectly aligned/centered with the sensor, so not all of the image area is projected onto the sensor.

[FotoChris]

Maybe it can be useful to someone. I did another test this time using the Raynox DCR 150 tube lens system from WeMacro instead of the Nikon PB-6 bellows. In this case no problem, the entire sensor is covered. So in your opinion the problem is that the bellows is not perfectly aligned?

In my opinion there could be two things at fault:
the bellows: the standards could be crooked or the bellows collapsed on one side
the adapter: there's an obstruction or it's not properly mounted with a pretty huge slant.

[ray_parkhurst]

It doesn't take huge misalignment of the front standard to mess things up. 1 degree will produce a 3.5mm shift on 200mm extension.

You could try tweaking the bellows a bit to see if you can improve/degrade the decentering. Even on fairly stiff bellows it's possible to move 1 degree without doing damage.