Iodine bleaching, China bleaching... any expertise?

M Carter · Dec 21, 2017

Struggling with china bleaching - where you bleach a fully selenium toned print in iodine. Any chemistry experts who can pipe in?

So, Tim Rudman's recipe:

Methylated spirits 100.0mls
Iodine crystals as much as will dissolve
Dilute 1+10 for use.

For starters, "as much as will dissolve" seems a little random. As will dissolve in an hour? A day? I guess I can suss this out more accurately, the stuff takes some time to dissolve though.

Methylated spirits - a little hard to find, but denatured alcohol seems to work OK? (I have a small bottle of methyl for dry iodone bleaching with thiourea, denatured is cheap and readily available).

So, dilute the strong iodine solution (or any store-bought tincture of iodine) with water and you get… a LOT of green-black precipitate, like the iodine reacts with the water. So I diluted the strong iodine with denatured alcohol instead of water and it avoids this mess.

Tried this with a partially toned print - pre-soak a print and hit the iodine bleach - BOOM, shazam, amazing reds and yellows… and then green-black staining, esp. in the highlights, which seems to be where the iodine reacts with the water in the print. The back of the print goes full green-black as well.

Going to fixer eventually clears the black stains, but also messes with the new tonality, returning it to something more like a ferri-bleached print. Redevelopment will clear any remaining staining, but then you're back where you started.

So, tried pre-soaking a print, and then soaking in denatured alcohol. The alcohol doesn't really drive the water from the print though. Black-green staining remains, print back goes black until fixed.

I still need to try this with a fully-toned print - in this case, the iodine supposedly bleaches the selenium-treated silver, turning it red. Played with this a bit, may have to really tone my prints more.

Anyone had better luck with this process? Trying to see if I can get MGWT to produce tones more like Ektalure or PWT in lith printing - MGWT seems to be a bit of a one-trick-pony color-wise (chocolate-browns) but I've seen some really popping oranges with iodine - it's more a question of preserving that color.

MrBrowning · Dec 21, 2017

I realize I could use google to find an answer to this but I am feeling lazy so what is China Bleaching?

Andrew O'Neill · Dec 21, 2017

https://www.photrio.com/forum/threads/is-there-a-bleach-for-selenium-toned-prints.129494/print

Scroll down to page 5.

mitorn · Dec 22, 2017

M Carter said:
...Iodine crystals as much as will dissolve...

I can help with that part:
As much as will dissolve usually means you prepare a saturated solution….You add iodine crystals till they won’t dissolve anymore.
Should be something around 23g Iodine per 100ml Methanol at 25°C.

Ian Grant · Dec 22, 2017

You really should have some Potassium Iodide in that Iodine bleach

Ilford IR-4 Iodine Bleach

Potassium Iodide . . . . . 16g
Iodine . . . . . . . . . . . . . . . 4g
water to . . . . . . . . . . . . . 1 litre

To use mix 1+19 with water, fix in plain hypo to remove any yellow stains..

Actually apply fixer with some cooton wool, if there's any stain left place in some developer and it'll disappear this is a bleach I used a lot for work in the 1970s & 80s. I've never heard of China Reducer.

Ian

M Carter · Dec 23, 2017

Ian Grant said:
You really should have some Potassium Iodide in that Iodine bleach

Ilford IR-4 Iodine Bleach

Potassium Iodide . . . . . 16g
Iodine . . . . . . . . . . . . . . . 4g
water to . . . . . . . . . . . . . 1 litre

To use mix 1+19 with water, fix in plain hypo to remove any yellow stains..

Actually apply fixer with some cooton wool, if there's any stain left place in some developer and it'll disappear this is a bleach I used a lot for work in the 1970s & 80s. I've never heard of China Reducer.

Ian

Thanks - but what's the purpose of the Iodide? And I'm specifically after china bleaching of selenium-toned prints, a pretty specific process. And very curious about the green-black precipitate and the buildup of green-black staining in the paper. Seems to be what happesn when Iodine mixes with water. (See my first post). Getting the stain out takes so much fixing or developing that it negates the toning/bleaching.

Damn, I wish Tim Rudman lived next door!

Ian Grant · Dec 23, 2017

The iodide keeps the Iodine in solution, it's preferable to alcohol, you can also use Potassium or Sodium Bromide instead.

You're using the wrong term China it should be Chinese and is about partially or completely removing the Silver image just leaving the Orange selenium image with a weaker or no silver image. Use the Iodine bleach weak with good agitation

A lot is going to depend on the paper as well as development when it comes to the strength/colour of the Selenium image, you'll need to experiment. Warmtone paper and warmtone developers would probably be the best.

Ian

Craig75 · Dec 23, 2017

In his book he fully tones a print in 1 to 2 selenium for 15 minutes before bleaching - which to my very limited knowledge seemed a strong solution and a long time.

maybe to split tone you need to hit it with stronger selenium concentration?

(as random unsubstantiated thoughts)

Ian Grant · Dec 23, 2017

Craig75 said:
In his book he fully tones a print in 1 to 2 selenium for 15 minutes before bleaching - which to my very limited knowledge seemed a strong solution and a long time.

maybe to split tone you need to hit it with stronger selenium concentration?

(as random unsubstantiated thoughts)

Then that's not Warmtone paper as at 1 to 2 it would be Reddish no silver image left within a few minutes.

Ian

Craig75 · Dec 23, 2017

Ian Grant said:
Then that's not Warmtone paper as at 1 to 2 it would be Reddish no silver image left within a few minutes.

Ian

he shows a MGIV wedge and a MGWT wedge that have been selenium toned 1:2 for 15 minutes then fully bleached and both go a vivid orange. However the MGWT one shows substantial density loss across the board so it looks like you need to overprint by at least a stop and a half to keep all your tones

john_s · Dec 26, 2017

I'm away and can't access my Tim Rudman toning book. I attended one of his toning courses and the example he displayed was spectacular. I can refer to it in a couple of days, unless someone does it beforehand.

M Carter · Jan 13, 2018

Ian Grant said:
The iodide keeps the Iodine in solution, it's preferable to alcohol, you can also use Potassium or Sodium Bromide instead.

You're using the wrong term China it should be Chinese and is about partially or completely removing the Silver image just leaving the Orange selenium image with a weaker or no silver image. Use the Iodine bleach weak with good agitation

A lot is going to depend on the paper as well as development when it comes to the strength/colour of the Selenium image, you'll need to experiment. Warmtone paper and warmtone developers would probably be the best.

Ian

The name "china" comes from China Hamilton, who developed the process with Liam Lawless, as I understand it. I've heard both terms used.

While I appreciate all the discussion, my original question wasn't about papers or selenium times but about things like "dilute 1+10", which, with water, does the mess of green blobs - so iodide will allow water to be used? And will that bleach formula work for bleaching selenium-toned images over to reds, or is this more of a basic bleach?

Wondering if alcohol is still needed in this case? Damn, I wish Dr. Rudman would re-publish the toning book as an eBook! Thanks for the info, I'll order some iodide. While this process can be a very extreme look, I've got a neg that would look really cool with some more fiery colors.

E. von Hoegh · Jan 13, 2018

I don't know about toning, but "methylated spirits" refers to ethyl alcohol rendered "undrinkable" by the addition of methyl (wood) alcohol, it's an old term. Commercial denatured alcohol uses other materials usually isopropyl alcohol as well as methanol.
denatured alcohol - http://www.sciencelab.com/msds.php?msdsId=9922820 This has isopropyl alcohol, 3 to 5 per. cent.. don't know if this could cause your precipitate. If iodine is primarily soluble in alcohol, and relatively insoluble in water, adding water to the saturated solution of iodine/alcohol would cause a precipitate.

Ian Grant · Jan 13, 2018

M Carter said:
The name "china" comes from China Hamilton, who developed the process with Liam Lawless, as I understand it. I've heard both terms used.

While I appreciate all the discussion, my original question wasn't about papers or selenium times but about things like "dilute 1+10", which, with water, does the mess of green blobs - so iodide will allow water to be used? And will that bleach formula work for bleaching selenium-toned images over to reds, or is this more of a basic bleach?

Wondering if alcohol is still needed in this case? Damn, I wish Dr. Rudman would re-publish the toning book as an eBook! Thanks for the info, I'll order some iodide. While this process can be a very extreme look, I've got a neg that would look really cool with some more fiery colors.

It's Tim Rudman who uses the term Chinese toning as opposed to China and it appears that's how it was termed by China Hamilton as well.

An iodine bleach is about all that would work, iodide or alcohol is just there to make the Iodine soluble. I used the Ilford IR-4 Iodine reducing bleach stronger than 1+19 when I wanted to cut the silver to white base completely, probably about 1+3 but I was only using less than a few ml at a time, really mixing drops, but I was using it almost every day at fork for a decade

Choice of paper and developer will make a huge difference with this process as it does with any toner, I suggest you do some tests with old test strips. You will need to experiment with selenium toning times and the strength of the toner, I keep some KRST made up at 1+3 for neg intensification.

Have you tried Flemish toner that's a Selenium-Sulphide direct toner and gives very red essentially Selenium tones. I have the formula I use in my darkroom (I've just locked it up, it's dark, mid evening here and it;s down the bottom of my garden).

Ian

Ian Grant · Jan 13, 2018

Ian Grant said:
It's Tim Rudman who uses the term Chinese toning as opposed to China and it appears that's how it was termed by China Hamilton as well.

An iodine bleach is about all that would work, iodide or alcohol is just there to make the Iodine soluble. I used the Ilford IR-4 Iodine reducing bleach stronger than 1+19 when I wanted to cut the silver to white base completely, probably about 1+3 but I was only using less than a few ml at a time, really mixing drops, but I was using it almost every day at fork for a decade

Choice of paper and developer will make a huge difference with this process as it does with any toner, I suggest you do some tests with old test strips. You will need to experiment with selenium toning times and the strength of the toner, I keep some KRST made up at 1+3 for neg intensification.

Have you tried Flemish toner that's a Selenium-Sulphide direct toner and gives very red essentially Selenium tones. I have the formula I use in my darkroom (I've just locked it up, it's dark, mid evening here and it;s down the bottom of my garden).

Also have a look at the work of Bob Carlos Clarke, his books "Illustrated Delta of Venus" and "Obsessions" are his early toning work, Dark Summer is his best work though, he was by far the best exponent of toning, Rudman's never even got remotely close. Agfa used Bob Carlos Clarke's work in their advertising in the 1980's early 90's, he used Dye coupled toners to produce colour prints from B&W negatives, at that point Tetenal made kits. Search Colourform here for the original 1950's Johnson's version

Ian

M Carter · Jan 19, 2018

Ian Grant said:
An iodine bleach is about all that would work, iodide or alcohol is just there to make the Iodine soluble. I used the Ilford IR-4 Iodine reducing bleach stronger than 1+19 when I wanted to cut the silver to white base completely, probably about 1+3 but I was only using less than a few ml at a time, really mixing drops, but I was using it almost every day at fork for a decade

Choice of paper and developer will make a huge difference with this process as it does with any toner, I suggest you do some tests with old test strips. You will need to experiment with selenium toning times and the strength of the toner, I keep some KRST made up at 1+3 for neg intensification.

Have you tried Flemish toner that's a Selenium-Sulphide direct toner and gives very red essentially Selenium tones. I have the formula I use in my darkroom (I've just locked it up, it's dark, mid evening here and it;s down the bottom of my garden).

Ian

Thanks - I'm specifically after getting that sort of "Ektalure with mature lith developer" look - particularly with MGWT as my classic cad papers dwindle, and I've kinda made it work once with Iodine and alcohol - really crazy reds/yellows. And that was a selenium-to-completion print, but it was like a 4x4 scrap. I just got my Iodide in the mail so I'll play with it this weekend. (Like I mentioned earlier, not an all-day-every-day process, but it can be really stunning with the right image). Now I just wish there was a faster way to get those little iodone balls to dissolve!

(EDIT - as I understand it, the look comes from selenium to completion and bleaches the selenium-whatever-molecule-whatsit down to reds).

Ian Grant · Jan 20, 2018

That Selenium to completion look (in KRST) is rather similar to the Selenium-Sulphide Flemish toner, I have some on my shelf so if I get a chance I'll do a test later today or tomorrow and post a scan.

Ian

M Carter · Jan 20, 2018

Ian Grant said:
That Selenium to completion look (in KRST) is rather similar to the Selenium-Sulphide Flemish toner, I have some on my shelf so if I get a chance I'll do a test later today or tomorrow and post a scan.

Ian

Thanks, I'd be interested to see it - so far I'm finding MGWT to have a pretty narrow toning look available... might have to look into Seagull warmtone, the FB lith group reports it liths well.

Iodine bleaching, China bleaching... any expertise?

Moderator

Privacy & Transparency

Privacy & Transparency