Does the bleach bath influence photos colors?

Yes, this is my conclusion after having used two different bleaching baths, one made of potassium dichromate and sulfuric acid (Franz Dietrichs) and the other the common ferric EDTA. The pictures direct scanned and without any corrections of the scanner gave these images:

Pic. 1 - Dichromate-sulfuric bleach

Pic 2 - Ferric EDTA bleach

Both are clouded the same way, must be the scanner default setting because every negative comes like this if you don't use color or level balance. As first approach to the final colors, I made for both of them level balance automatic at scanning:

Pic 3 - Level balance to pic 1

Pic 4 - Level balance to pic 2

Comparing the two pictures above, I concluded that the dichromate-sulfuric bleach gives in general pictures where the green prevails over blue and with the ferri EDTA bleach red is not much represented. So, I added more blue to the picture 3 and more red to the picture 4, obtaining the following:

Pic 5 - Color correction of pic 3 with more blueish hue

Pic 6 - Color correction to pic 4 with more redish hue

 Global appreciation: I found ferric EDTA better than dichromate-sulfuric because the colors look more natural, but both may be used because after correction they are acceptable and, on the other hand, you may have a more artistic view using dichromate-sulfuric.

But, neither Pic 5 nor 6 are at the final stage of the work you must undertake to make the best of these negatives. Both of them need more contrast and the second needs a little more color sturation, I think.

Pic 7 - My proposal for the first pic

Pic 8 - My proposal for the second pic

Why is Dignans method a good choice?

When developing according to Dignans method a certain amount of the first bath, where the color developer (CD-4) is, will be transported to the second bath, where a basic solution will permit the development to take place. But this bath remains uncontaminated and may be used until the volume is not enough to cover the film in the developer tank. Then you just add to this bath a certain amount of fresh solution of CD-4. I suggest to add 0,5 liter each time, so in general we may have between 500 and 700 ml of solution, witch is enough to develop not only 35 mm but also 120 films.

The second bath don't need to be stored, it is said to pour down the drain. But if you reuse it, I think it will work if the pH is about 11,6 to 11,8 or even 12. Today I made a try with pH 13 and less time, I still don't have results to show but I leave this two pictures of yesterday, developed with the same solution I already used twice. No signs of exhaustion,

No color correction at scanning

Correction with more blue and green

In general, the film I am using, Agfa Plus 100 ISO, without any correction, shows a shift to magenta when set to automatic color correction at scanning. The color shift may be caused also by the bleach bath of dichromate and sulfuric acid I am using. To be sure, I will try a classic ferric EDTA next time. This is not a very big disadvantage, ferric EDTA is available at ebay or somewhere else, you don't need to by a standard kit to get it.
On the other hand, the bleach I am using seems to last almost forever and you only need very weak solution of it for 2-3 minutes only. Like suggested by Donal Qualls, I am using a stop bath of vinager between the second developer bath and bleach, to prevent the formation of gas of bleach reacting with sodium carbonate and hydroxide.

Weighting small amounts

To weight small quantities of substances, you need in general a precision scale, witch is not a common domestic object. But a scale to weight with precision more than, let us say, 10 or 20g a common kitchen scale is enough.
If you then need to weight just 0,5g of a substance you may dissolve 10g in 100 ml of water and use just 5 ml of this solution. If you need 4,5 g, you can dissolve also 10g in 100 ml and use 45ml and so on.
Adopting the rule of 10g/100ml solution you only multiply the amount in g by 10 and you have the amount in ml.
If, instead 10 your scale is weighting 11 because it is not precise, instead of the 0,5 you will be putting 0,55, only 10% more, waht is not so bad. But if you try to weight 0,5 and you fail 1 g it is then a very large mistake, 3 times more.

Dignans method for color negative film

I found this recipe some time ago, but never tried it like it is. Today I exposed a piece of 35 mm color film, C-41,  and develop it according to Patrick D. Dignan and Donald Qualls, but I changed a little the recipe according to my needs or possibilities:

Bath one:
5,5 g CD4 or 110 ml of a 5% solution of CD4
4,5 g Sodium Sulfite
Water to make 500 ml
(here I left bisulfite out because I don't have it and I don't know why it is there, maybe the bath preserves better but with just sulfite it will last for a while, I hope).
First minute agitation and then leave for some more 5 standing at room temperature

Bath two:
22,5 g Sodium Carbonate
1-2 g Sodium Hydroxide
0,5 g Potassium Bromide
Water to make 500 ml
(in the second bath I used a little of Sodium Hydroxide to get pH = 11,8 instead of 10,9 I was reading, maybe my tap water is too acid, I suppose).
6 minutes always stiring at rooom temperature.

Then I made the bleach bath of Franz Dietrich, dichromate+sulfuric acid, very diluted, 1:5, and just one minute always stiring and then fixer, Sodium thiosulfate, prepared with Sodium Sulfite and Sulphur. See Recipes.

Well, it works very good indeed and without coffee. I think I already tried without coffee but only with sodium hydroxide, some grams only, and it was a disaster. If the second bath was again with sodium hydroxide, it would need some acid to lower the pH. Here are some of the pictures developed in Dignans room temperature method.

Example 1

Example 2

Example 3

Like processed in C-22

Old color films were processed according to C-22 process, that required several chemicals but the main difference was the color developer, instead of CD-4 it used CD-3, still used for color slides in standard process E-6. Another important difference is the change of the bleach bath in witch entered  the environmental pollutant Potassium Ferricyanide replaced with Fe(EDTA), ferric ethylenediaminetetraacetate, as far as I could determinate.
Of course there were changes in photos quality, some of the photos treated in C-22 were very different from the modern ones, with their vivid colors. But not only the developer was other, the bleach bath determines also the color quality. I discovered in the internet this photo, among others, here.

Photo from the 70's

This was for me an important issue, I can see that some of my first attempts to develop color photos in a different way, gave also similar results, where we hardly can talk about color.

One of my first attempts

I have been using CD-4 as color developer, but the bleach I used was based a recipe of Franz Dietrich,1988, with Potassium dichromate and Sulfuric acid, both of them easy to get for me. Potassium dichromate and Sulfuric Acid (see Recipes, Caffcol I) require careful handling but the solution is very weak, I have been using the recipe in a 1:5 dilution with water. So, the working solution is not such a problem to deal with, care must be taken when dealing with the pure substances, gloves, fresh air mask and googles are recommended.

But this color is, for me, mainly a matter of the bleach used. So, if you want to achieve a 70's look, try this bleach, but be very precise in the time because it may bleach completely your film if you give it time to act.I have been working with 3 minutes bleach constant agitation to prevent uneven bleaching like in the photos above.

Another example pf a photo of the 70's but made in 2012

The naked camera

Well, I bought at ebay a very cheap 35mm camera, with the shutter not working properly, like announced. Besides, aperture stuck and shutter blocked when camera is set to infinity. I started taking pieces from it to repair other simpler cameras, thinking that such a sophisticated camera, a Konica auto S2 with 45MM F1.8 Hexanon Lens, would be difficult to repair. And I went on taking pieces until it was reduced to a simple model where I could understand how it works, why the shutter was blocked and the aperture stuck. But all the automatic was gone, no need for battery, it is now a manual adjustable camera, and is much lighter than it was first, without unnecessary pieces that makes the camera strike.
Well, here are some photos of the camera and believe me or not it is working perfectly, manually.
The problem with the aperture was a small spring that keeps the aperture opened that need replacement. And the shutter blocked was just because somebody already tried to repair and putted a long screw instead of a shorter one and this screw was preventing the shutter to work only when it rotates to infinity. This caused the shutter release to be actuated and no further movement was possible. Just a small screw that perhaps disappeared and was replaced by a longer one. One of the two screws that sustains the black waist around the distance crank ring.

Without shutter/lens

Lens back to body

Here I had to file a little

View from the back

I think the next weekend I will be photographing with this camera, lens f:1,8 great opportunity to try this precious lens.

Developing color with hair dye?

Yes, many people claim it is possible and I already had some lucky results. I have tried with two different brands and both of them worked more or less promising.
But after the first time, the same hair dye, used days after, failed. The same with the other brand. So, I came to the conclusion that it only works with a new unopened hair dye. After that, maybe it looses this property in contact with air or light or I don't know what. Maybe I should have done like I did with CD-4, some grams of metabisulfite to preserve it against oxidation.

Because of this, I will have to kill, by now, CAFFCOL III, it would be very expensive to buy a new hair dye each time I develop a film. The recipe will stay there, you may try it, but I give no warranty on the results, it's up to you. If you discover something that makes it work always, please tell me.

Later on I will buy a new package of hair dye, dilute it with some preservative and see what happens then.

But now, after the disaster I had today with a complete 36 exposures film to trash, I am about experimenting the 2-bath developer with CD-4, CAFFCOL II.

First time with Brand A

First time with Brand B

Second time with brand B, almost bleach by-passed.

The second time with brand A gave null result, nothing to see, no color development at all, all silver was bleached and fixed out and no dye remained, very little in the first photos, a pale shadow can be seen.