problems w/ blotchy skies

[htimsnhoj]

Hi All,
I shoot w/ a Sinar F2 utilizing lenses from 75mm to 150mm generally w/ a bag bellows. I use Fuji Acros quickloads in a fuji quickload holder. My exposures are longish, from 12 sec to 2 min.
The work I do is generally shot during civil twilight and I try to keep the skies pretty dark. I have been working on a commission that required me to shoot later in the morning and have brighter skies and thats when I noticed that I have these uneven and blotchy skies. They appear to be shadows and highlights in the skies that are completely clear southern california mornings. I have borrowed other lenses and still seem to have the same problem. Obviously it goes away when full daylight skies blow out to white and when they are extremely dark. Do I have a leaky bellows, is it the holder? Please help.

[domenico Foschi]

To me it looks like a processing problem.
How do you develop your film?

[htimsnhoj]

I use a lab to process my negs. They are a small outfit and the guy does all the work by hand. I will have to ask what kind of tanks he uses and how he process' the film.

[Rick Olson]

Agree ... that's a processing problem.

[Mattg]

That's definitely processing.

I had a similar problem until I started doing a pre-soak and constant agitation for the first 30 seconds. That was with small spiral tanks.

Your third picture shows an interesting effect where the areas of low density like the palm tree seem to have influenced adjacent areas of higher density, this could indicate exhausted developer and/or insufficient agitation.

[Toyon]

Dump the lab, buy a Combi-Plan, or tray process.

[Rob_5419]

Yup. It's not your holder, nor your bellows.

The strand-pattern is classic of agitation marks - usually excessive agitation in relation to the concentration of the developer for the time that the film is developed.

One way around it is to try 'presoaking' your film in the Combiplan (Combiplans are fine, but you need to be careful with agitation) for a few minutes in plain tap water for 3 minutes. Then start your development process, and agitate randomly (rather than up and down, or just side-ways - combine uneven movements) for as little as 2 seconds every 30 seconds.

If you reduce the concentration of your developer and have a semi-standing development with even less agitation, you'll find that the streaks virtually disappear.

But the overall streaking strand effect is more to do with how you agitate, rather than the concentration or the time or the method of development. Looks like you might need a bit more practice that's all.

Good luck.

[Nathan Potter]

There is some correlation between the building structures and the sky streaks indicating, as Mattq points out, an adjacency effect between high and low density area in the neg. Looks to me like a developer depletion phenomena coupled with a lot of vigorous agitation during film development (tube development maybe?). I also suppose it could be scattered early morning light streaking from adjacent city sources?

Yes, dump the lab. At least as a test.

Nate Potter

[Mark Sawyer]

I'll just chime in with the others; yes, a processing problem in the developing or the lack of a pre-soak. (With stand developing, I don't do a pre-soak, but have 15-30 minute development times. If I'm agitating for a shorter time, yes, a 3-5 minute pre-soak is needed.)

[C. D. Keth]

That looks a lot like when I was just starting and I tried processing one sheet, emulsion up in the bottom of a tray. it streaked up a storm and looked a lot like that.

[Frank Petronio]

Learn how to cut path selections in Photoshop....

[Mr. Doyle]

I have had this very same problem and in my case it was not the processing.
If there is moisture in the air (early morning, late evening) or you are bringing the quickloads from cold to hot (coolbag to desert heat) the quickloads can get damp and leave 'mottled' marks on the image usually most obvious in a cloudless sky. Long exposures increase the effect as the cardboard holder can get damp when pulled out from the back..
I am pretty certain this is the case here as this is something that took me months to discover..

[Andrew O'Neill]

This effect happens when I am using stand development with no agitation cycles at all. Noticeable between high and low exposure areas. Ask the guy who develops your film what developer he uses, how fresh it is, what development method he uses, and how much agitation he gives.

[Andrew O'Neill]

Learn how to cut path selections in Photoshop....


Fix the problem at the development stage first. A lot of people don't own photoshop.