Infinity focus problem w/ 28mm HR and cambo wide ds

[maeda]

Hi,

I just received my mamiya DM33 (same as leaf aptus II 7) and impossible to make a shot in focus at infinity with my rodi 28mm HR.
Do i have to send my cambo wide ds with the lens and digital back for calibration to cambo or Rodenstock ?

Thanks

R.

[Rod.Klukas]

First-Is anything in focus closer than infinity?  That would tell you that the mount is too long and requires adjustment in shortening the lens position relative to the sensor.
The distance to the sensor from the rear of the lens to the sensor should be approximately 16.4 mm from the rear edge of the rear end of the lens.

Measure by removing the back from the mounting adapter and measure through the back.

This will give you an idea what is going on.
Hope this helps,
Rod

[Doug Peterson]

Cambo infinity adjustment can be done by most value-added Cambo dealers. Assuming you purchased from a value added dealer I'd contact them before Cambo to save the cost/time of shipping to the Netherlands. If you bought it used from eBay or similar then you can attempt to adjust infinity yourself if you're a power user (it's not overly challenging, but you're taking the risk of messing it up which would void any warranty) or contact Cambo and have it sent in for adjustment at the factory. However, the issues is back-to-lens calibration so they need more than just the lens - they need your kit (another reason why it will be easier to go through your dealer assuming you have one).

An unofficial guide to user-adjusted infinity (again, not overly complicated but proceed at your own risk - officially cambo does not endorse the end-user doing this and suggests it be done by a qualified dealer or by Cambo itself):
http://www.getdpi.com/forum/380561-post2.html

[Rod.Klukas]

Re the Cambo instructions, I would say they look fine except if you have a 80mp back with some lenses.
Some lenses exhibit an exceptional amount of focus shift in the red range and so if you test at the widest aperture, and don't stop down to at least F11, to cover the focus shift, you may not be sharp as you might be.
I might recommend stopping down one stop from wide open to cove some of the error.
Rod

[maeda]

Thank you everybody.
I bought the lens second hand. I'll try to calibrate the lens myself tomorrow.
I'll share my review with pictures if it works

R.

[maeda]

So i calibrated the lens myself and it works so well !!!
Thank you very much for the link Doug !

It's very easy and quick to calibrate your lens.

I think the only problem that you can find is to damage the screws.
My advice : Use a very good quality screwdriver as the one i used : FACOM AEFP.00x35

http://www.facom.com/Facom/webcatalogue/facom/fiches-produit/sku_html/en/AEFP-00X35_en.html

Thanks !