Focus problem with Rodenstock 40 HR

[msertac]

I have recently noticed focusing issues with Rodenstock 40 HR Cambo mount. Right and left side of the image in perfect focus while center has not equally focused. Any recommendations?
Thanks

 

[Paul Spinnler]

Do you have a copal shutter, do you think the lens might have gotten a hit?

Typically, if it is asymmetric left to right it is the shuter that's bent on one side. If the center is different from the sides, then it is most of the times also the shutter but in terms of the distance between the front and back lens groups - you'd use spacers to check.

Worst case some internal elements moved in the symmetric sides scenario - then its gonna be a very expensive repair.

If you can, replace the shutter with one from another lens and or try spacers behind the shutter to change the distance between the lens groups. If the center stays unsharp vs. the sides you might have the bigger problem mentioned.

 

[msertac]

Do you have a copal shutter, do you think the lens might have gotten a hit?

Typically, if it is asymmetric left to right it is the shuter that's bent on one side. If the center is different from the sides, then it is most of the times also the shutter but in terms of the distance between the front and back lens groups - you'd use spacers to check.

Worst case some internal elements moved in the symmetric sides scenario - then its gonna be a very expensive repair.

If you can, replace the shutter with one from another lens and or try spacers behind the shutter to change the distance between the lens groups. If the center stays unsharp vs. the sides you might have the bigger problem mentioned.

Thanks much

 

[msertac]

It looks like lens barrel is loose. It is moving

 

[Paul Spinnler]

It looks like lens barrel is loose. It is moving

well that’s the best case scenario and an easy fix

 

[rdeloe]

Are the lens cells screwed in tightly? What you're describing is the classic problem you get when the lens spacing is incorrect for the sensor. Fixing this might be as simple as tightening down the lens cells in the shutter. Finger tight is key here. Don't use any tools, and don't break a sweat!

 

[rdeloe]

P.S. You're in the "Buy and Sell" forum -- wrong place for this conversation... Hopefully the moderator will notice and move the thread over to Medium Format.