Weird artifacts when using Tmax 100 for black-and-white reversal processing

Question

I'm new to film development and previously managed to develop two rolls of Kodak Tri-x 400 (let's call roll A and B) using reversal processing: D-11, dichromate bleach, D-72. Today I tried to develop another roll of Kodak Tmax 100 (roll C). But the result was not good:

1. roll C is very dark (my camera was set to DX ISO 100 when taking the pictures) though most of the photos were properly exposed, and I even used last 10 photos to test different compensation: 0, +0.1, +1, all are about the same darkness. Therefore, the contrast is way lower than roll A and B.

2. what's worse, I noticed some artifacts (see the photo below, you can notice the abnormal color around all dark parts) in the dark region of many photos. Suspect it was so dark so something got wrong during the reversal process.

3. The phenomenon in 2 also happened to some photos of roll A, but not roll B.

4. I believe most of the photos are properly exposed (I could get some decent photos if I had used negative film development, I guess).

Here are two sample photos from roll A:

Most photos are good:

But are sporadically with artifacts in dark zone:

Here is a sample photo from roll B (looking good): All photos are good, including portraits in similar light conditions:

Here are the samples from roll C (too dark, artifacts around dark region):

Was properly exposed, taken on a day with good light condition: Bad portrait because of the artifacts (look at the hair), also noticed the artifacts are in the previous photo: Too dark, also suffer from the artifact problem:

TL;DR: I tried reversal processing using D-11, dichromate bleach and D-72, but (1) got very dark photos when switched from ISO 400 to 100 (both were properly exposed), and (2) also got annoying artifacts in dark zone when it becomes really dark. But for the same formula, roll B is well developed. roll A is the same type of roll as roll B, but with different ISO from roll C.

EDIT: I recalled that I did notice greenish color in the problematic area during the second exposure (after bleaching and clearing). Does that mean the clearing is not enough and some parts were still contaminated by dichromate?

Answer 1

Difficult to trouble shoot but my best guess -- the dichromate bleach was exhausted or contaminated.