Negatives are purple after developing

[JeremyLangford]

So I started a Black and White Film photography class at my high-school (I'm a senior and this is the second time I've taken it). Today I was showing another student how to develop film (Kodak TMax400 in D76) and after we finished, the roll had a purple cast.

We asked my teacher about it and she said that we didn't fix long enough (We fixed for 18 minutes). She said that new Kodak Film was being made differently. She also said that we could remove the purple cast by letting the film dry overnight and fixing it again tomorrow.

Does what she is saying sound right? I am kind of nervous because I have a roll of Tri-X400 that I'm currently shooting and I don't want it to turn out purple. Any tips?

 

[steveohan]

18 minutes for fixing?? wow...
im not sure of the technical explanation, but a lot of my b&w film will have a slight purple cast after souping. it usually goes away when the film is completely dry. it has no effect on my scans.

 

[tmfabian]

the purple cast is normal for most kodak and illford films, some films have insanely blue colored bases, and i saw one with green base.
the only film i've used so far with a very neutral base is fuji neopan which is quite nice.
18 minutes is way overfixed.

 

[FrankS]

The fixer may have been exhausted.

 

[Chriscrawfordphoto]

Rapid fix takes 5 minutes for Tmax films. Regular non-rapid fix should not be used for Tmax, these films require the stronger fixer. The purple is removed by washing, not fixing. Wash 15-20 minutes and it will go away.

 

[JeremyLangford]

This is why I want to develop my own film at my own house, with my own chemicals. I'm fine with having to learn things on my own, but I am always worried that some of her chemicals are bad. She wrote on the board that we needed to fix for 18 minutes because the longer we fix, the less purple cast we will get. I have no idea how old her chemicals are. I can ignore her timing instructions and have complete control over how long I can develop, stop, fix and wash but I have no control over keeping her chemicals from going bad.

We pour developer down the sink after we develop film, but we pour the stop, fix, and HCA back into their bottles to reuse for the next person. I am assuming that she is right on teaching us to do that? How many times should you be able to use the same stop, fix, and HCA?

 

[Never Satisfied]

If you read the directions for most generic fixers 5 minutes or there abouts is recommended; 18 Minutes is too long. If the fixer is exhausted as suggested there will be some base residue around the spoket holes. If the base is clear, meaning transparent on the un-exposed portions of the film, ie between the frames and the spokets, the fixing is most likely OK.
A lot of film bases have a purple cast especially the old SS Neopan, don't worry about it unless it effects the way the negs scan or print.

Andrew.

 

[maddoc]

That's one of the reasons why I stopped using Tmax400, getting rid of the residual purple stain is difficult and scanning this slightly purple film isn't easy either. I got better results using XTOL with Tmax films, less purple residual. Rodinal in high dissolution (1:100) gives the clearest negatives, when draining the developer it has a dark purple color so must have removed the dye from the base ?

 

[steelydam]

Agree it's a rinse thing. I've been getting it with the new TMax 400 after developing in XTOL. I did extend my Kodak Rapid Fix time to about 7-8 minutes but it was still purple. After fixing and before doing my "real" rinse I fill my tank with water and do about 30 inversions, dump and repeat 2 more times. After I do one of these 30 inversion cycles and dump the water, it has a purple cast that lessens each time.

 

[thetooth]

what everybody else said . fix was too long . fixer was probably exhausted and the rinse cycle will remove the purple cast .

there are many different concoctions for the development end , but the fix and rinse is pretty standard ( i usually rinse for twice as long as i fixed i.e.: 5 minutes fix = 10 minutes rinse ).

i do my own at home with a couple paterson tanks and the kitchen sink . just clean up well afterwards some of the chemicals are toxic .

pick up a couple of books at your library on the subject . good luck

 

[pbhome]

I believe that the purple thingy is anti-halation coating. If you pre-soak your film with just water, it will come out.

I don't believe that it has anything to do with fixing.

 

[tmfabian]

BINGO!
I was trying to remember the word for what the coating was called.
A good pre-soak and a decent wash will get rid of MOST of the color, but it'll never be 100%. I presoak for a minute and wash for an hour (2x30mins) with one of those bottom filled film washers for an hour and use a permawash in between the washes, but my ridiculously long wash is usually attributed to me going to the bar for a few drinks while my film is washing (there's a bar next door to my darkroom)

I believe that the purple thingy is anti-halation coating. If you pre-soak your film with just water, it will come out.

I don't believe that it has anything to do with fixing.

 

[maddoc]

~~ ... but my ridiculously long wash is usually attributed to me going to the bar for a few drinks while my film is washing (there's a bar next door to my darkroom)

LOL !! That is what I call "paradise" 😀😀😀 A bar next door to the darkroom, my dream ... 😎

Cheers,

Gabor

 

[mh2000]

Exactly! Fixing for extended periods just mean you are using your fixer as a wash. I let mine sit in distilled water for an extended period of time (maybe 20 min, maybe more) and it is all gone. I don't know where the rumor about fixing got started, but the purple has nothing to do with fixing...

Rapid fix takes 5 minutes for Tmax films. Regular non-rapid fix should not be used for Tmax, these films require the stronger fixer. The purple is removed by washing, not fixing. Wash 15-20 minutes and it will go away.

 

[nikon_sam]

Rapid fix takes 5 minutes for Tmax films. Regular non-rapid fix should not be used for Tmax, these films require the stronger fixer. The purple is removed by washing, not fixing. Wash 15-20 minutes and it will go away.

What Chris just said...

Rinse the film for the normal 10 minutes in running water THEN let it just sit in water for 5-10 minutes at a time...After sittting in the water pour it out and refill the tank again with water...each time you do this you should see a pinkish/purple tint in the waste water...Repeat this for as long as it takes to come up with clear water when poured out...
Letting the film just sit in water saves water and does the same as running water...
Check the lead edge of the film to confirm that the haze is gone from the film, drop it in Photo-Flo then hang to dry...

 

[JeremyLangford]

We pour developer down the sink after we develop film, but we pour the stop, fix, and HCA back into their bottles to reuse for the next person. I am assuming that she is right on teaching us to do that? How many times should you be able to use the same stop, fix, and HCA?

 

[martin s]

You can just put some undeveloped film in the fixer and wait till it clears. Note the time and double it, that's how long you're supposed to fix if you want to believe those Tetenal bottles 😉

Stop bath is unnecessary for negatives, I just use water.

martin

 

[ChrisPlatt]

2 drops of Edwal Hypo Chek will tell if your fixer is exhausted.

Chris

 

[rogue_designer]

We pour developer down the sink after we develop film, but we pour the stop, fix, and HCA back into their bottles to reuse for the next person. I am assuming that she is right on teaching us to do that? How many times should you be able to use the same stop, fix, and HCA?

Yes, reusing stop and fix is normal. I typically use my HCA as a one shot though (mix enough working solution from the concentrate as you need, then sink it when done).

If they used indicator stop it tells you when it's exhausted (turns purple).

Fix, you know its exhausted when it stops working. Unfortunately, figuring out how much you can re-use it isn't easy when you are all sharing chemistry (no way to know exactly how many rolls/sq. inches have been through it).

My best recollection about our college lab (for 8 guys) would mix up new fix every three days during average useage. But I was usually doing alternative process stuff, so I kept my own chemistry under my work station - I can't vouch for whether they needed to mix more often or less...

 

[Chris101]

2 drops of Edwal Hypo Chek will tell if your fixer is exhausted.

Hypo testing solution, by the way, is 5-10% potassium iodide. Drop in a drop, and if a cloudy precipitate forms (AgI) then the fixer is exhausted.