120 B&W negs look funny?

[joey_smith3]

<p>Hi folks, been lurking for awhile. Now I have a question please?<br>

Sent 1 roll of 120 to a south florida lab for process and scan. Sent another roll to a lab in Tampa.<br>

First one came back with a slight pink/magenta cast to the film. Tampa roll came back perfect nice strong contrast, no cast, clear edges.<br>

What caused the pink/magenta cast?<br>

Shot with the same camera/mamiya 1000s within a day of each other.<br>

Getting back to medium format and years of abstinence.<br>

I just wanted to check this camera for possible purchase.<br>

Thx<br>

Joey</p>

[steve_robb1]

<p>Just going to ask the obvious question first, were they both the same type of film?</p>

[rustys pics]

<p>What kind of film? It sounds like the lab either did not fix it or wash it long enough.</p>

[john_shriver]

<p>Pink? Sounds like T-MAX. More fixing and washing might help. But first just try leaving it out in the sun for a day, the sensitizing dye decomposes swiftly in the light. <br>

Also, it's harmless when printing or scanning.</p>

 

[david_l3]

<p>Was the film T-Max? It requires more time in the fixer and a little more wash time. </p>

[joey_smith3]

<p>1. Yes, they were the same type of film.<br>

2. They were T-max 120<br>

3. Sounds like the south florida lab needed to fix and wash more.<br>

John, you are right about the scanning. I had both labs do a full roll scan and when I loaded them up I saw no difference in PS.<br>

Thanks guys, I think the ? has been answered.<br>

Also, good tips for me when I start processing my own B&W in several weeks.<br>

Its been 15+ years since I last did it. Like a bike though, right!<br>

thx<br>

Joey</p>

[Alan Marcus]

<p >Black and white film and color for that matter have as their chief constituant a salt of silver. This is a crystal that resembles ordinary table salt which by the way is a salt of sodium. Silver salts are light sensitive and come in three varieties, iodine, chlorine and bromine. All three are crystals with a slight yellow color. The yellow cast causes them to absorb blue light (the opposite of yellow). Early films were only sensitive to blue thus they were called color blind. This is not good because colors other than blue are rendered black. Portraits of women particularly look horrible with dark lips and cheeks. </p>

<p > </p>

<p >A breakthrough occurred in 1873. Professor Hermann Wilhem Vogel (Germany) discovered that he could add dye to the mix and change the colors the crystals would absorb. First he made films sensitive to all colors but red and called them orthochromatic. Later using different mixes of dyes, in 1905, he extended the sensitivity to all colors and called the new mix panchromatic. By 1920 panchromatic films were universally on the market. </p>

<p > </p>

<p >T-Max is a panchromatic film and the slight magenta (red-blue) cast you see is residual sensitizing dye. The cast is harmless; it can be dissolved away in an extended water soak. A re-fixing in fixer and then a re-wash will accelerate the process. </p>

[wentbackward]

<p>Joey, TMAX which is pink is not fixed properly. Check the Kodak site it is in the specs very clearly (so you don't have to take my word for it). They recommend back into the fixer for longer. After 6 minutes of fixing I open the can and continue fixing with the lights on until the pinkish has almost gone.</p>