light halos on prints

[federikk]

hello all,
i've noted that sometimes i've some light halo on the prints, there must be something that causes this on the shadows region, only on the very same region of the frame. I've attached some images.

what can t be?
- enlarger lens?
- set of multicrome filters (once they get wet)?
- enlarger mirror?

it only happens sometimes, the negative is ok (i also scan it) and regardless of printing format.

thank you

edit:i've added higher resolution images (click on images to enlarge):
http://www.ildronista.it/?attachment_id=726
http://www.ildronista.it/?attachment_id=727

 

[JoeV]

Since it's a light-toned mark against the darker shadows, there's something obstructing the light path from enlarger to print paper. Could be internal to the lens, or contrast filters. First try cleaning the filters, and ensure they don't get wet or dirty. If it's the lens, you should be able to easily see the defect by examining the lens.

~Joe

 

[titrisol]

That is dirt in the lens or the condensor

 

[federikk]

the condensor

i've a durst 605 with B/W head.
light path:
bulb, mirror, filter, lens.

the lens looks ok, not very good but good enough if compared to cameras lenses. Shot with similar conditioned lenses with no hassle.

the mirror has some speckles, it's quite old, but the defect seems quite different.

bulb is durst opal.

are you prone to lens or mirror? i've no chance than buying another one if lens. If the mirror,is it a simple plain mirror?


very thank you

 

[federikk]

i've a durst 605 with B/W head.
light path:
bulb, mirror, filter, lens.

or do i miss something in the black box under the mirror, before the lens?

 

[titrisol]

BW head, means the one with the bulb
Then the black box between the lens and the negative is your condensor
There maybe some dust in there, be careful when cleaning and use just a blower/brush

I could not find a better pic than this