Underexposing lens?

zntgrg · 02-06-2008, 02:35 AM

Hi, i have a K110D with M42 adapter: i have many lenses in this mount, but i discovered that the last buy [a Pentacon 30/3.5] is underexposing by 2 stops. I realized it swapping it with my beloved Helios which is instead spot on.

The lens seems definitely clear, with no fungus or dust of sort. I remember i sent the Helios to service for oiling the focus ring and they cleaned and refocus it: maybe i'll bring tho the lab this also [since i paid 8 euros for this i have little to complain] but i'm also open to free advices

*christinelandon* · 02-06-2008, 03:54 AM

Two stops under is a bit much, so I'd concur with your decision to send the Pentacon for a CLA. Good luck, and I hope you've got a good relationship with your service center, so that your €8 bargain doesn't become a €40 disappointment.

Mike Cash · 02-06-2008, 05:01 AM

Have you tried the trick of covering the electrical contacts around the lens mount with aluminum foil? Works wonders.

zntgrg · 02-06-2008, 05:34 AM

Thank you all. Tried Mike, btw no differences and i'm warranty paranoid

Thank you also Christine.

Now i remember that the Helios before the CLA was 1 stop under...and i found even the focus out of a bit so i'll send hoping for the magic happens...it'll be a 30€ euro deal, i think [the last photo repairer in Verona is pricey, but also a god of the screwdriver].

Anyway, what a great lens if hazed and out of focus it delivered me razor sharp pics and wonderful tonal ranges!!