Stains on black and white negatives

<p>Hello Photo. net community<br>

Hope you can help me on this. I have just started developing my own black and white films at home. I use Paranol S but I follow the developing times for Rodinal. I notice sometimes the negatives have some stains on the top. I try as much as I can, to get the temperature right, agitation and time. The problem is that sometimes, this problem occurs and sometimes it does not. In the examples below, I used Rollei Retro 400S and it was processed at 20 degrees for 22 minutes, with 10 seconds agitation each minute.<br>

<img src="http://68.media.tumblr.com/d4ffff5ba59d0dea2d0dc49fecfaa132/tumblr_oj0jemTN2G1sq6fbqo1_1280.jpg" alt="" width="1280" height="826" /></p>

<p>Hello Manuel. I am going to say that the "stains" are what I call "surge development". This is over development created by swirling developer in your tank. My guess is you have 35mm film and if you check the entire roll, these marks are showing in light areas (sky, bright buildings, etc). This will "usually" show up in that part of the film that is at the bottom of the tank.<br /> I have a few suggestions to help. Try using a 3 minute presoak with demineralized water prior to the developer. ( I hope other readers will not start a rag on this bit. . . it works for me).<br /> You did not state the quantity of developer used. Try 75% of this amount with the same time. A lot of people get hung up on "ratios". The film will develop just right with "X" amount of developer and some ratios will give you too much chemistry, some not enough. If an improvement is achieved, try 50% and again compare.<br /> Your developing tank may be your culprit. Many of the plastic tanks have histories. I "standardized" on Nikor Stainless Steel tanks & reels some 40 years ago and only when experimenting on "new & exotic" developers do I see some "surge development".<br /> I have included a picture of my 450ml set up for either 35mm or 120. I use 3.0ml of 510-Pyro (current developer) for either film. . . this is my "X" for this developer. "X" in 450ml of DI water & the same time for either 135-36 or 120 film. Film type can vary.<br /> Please note that either film has a spacer underneath it's reel in the Nikor tank. This prevents "old developer" from swirling about the film and creating "surge".<br /> I hope some of this helps. Keep us informed how it go's in the New Year. Aloha, Bill</p><div></div>

<p>Hello Bill<br>

Happy New Year to you too...and much appreciate your response. Yes, these stains are more visible in the highlights and it is very annoying. I am not sure when you say quantity of developer. I used 1 part of developer for 49 parts of water. Is that what you mean? So, I could use less developer or processing for less time, maybe? Yes, I use a plastic tank which is not really the best. I will try your suggestions and see what happens. Thanks for your time. </p>

<p>Actually, to me it looks like there might not have been enough developer in the tank and the upper edge didn't get sufficient development. It would be important to figure out (if you can) which side of the roll was up. If you're using a plastic tank, make sure it's not one where the reel can ride up in the tank (ie. float). Be sure you're using enough to completely cover the film, but not so much that it's tough for it to move around when you agitate. And remember to tap the tank to dislodge bubbles after each agitation. <br>

I haven't used Paranol S or Rodinal, so I can't speak to the dilutions/times needed, etc..</p>

<blockquote>

<p>Be sure you're using enough to completely cover the film, but not so much that it's tough for it to move around when you agitate.</p>

</blockquote>

<p>Its a "Wives Tale" that one must leave air space for the chemicals to move sufficiently during agitation. I have been developing film since 1976 and always fill the tank full with no air space when doing inversion processing.<br>

If you notice a slight under development with no air space a 2.5% to 5% increase in development time will correct it as will 2 or 3 more inversions per cycle. If I were mixing for <em>even consistency</em> in the solution I would stir or leave an air space. </p>

<p>Too vigorous agitation with an air space may cause the developer to foam which could be the cause of your problem.</p>

<p>Hi Bethe and Charles<br>

Thanks for your responses. I thought that could be the reel was stuck above the chemicals. The instructions I received with my developing kit says 300 ml should be enough to develop a 35 mm film and 500 fora 120 mm. I did a test with water and 300 ml hardly covers the reel, so next time I will use at least 400 mm of chemicals to process. I think maybe I am agitating too much as well. I guess, I will have to make some changes, record them all and see the results. So far, all your comments have been really useful. </p>