Solar, add one teaspoon table sugar to 150ml distilled water. That should get you solidly into the green band.
To move out of the green and start seeing some yellows/oranges/reds try increasing your concentration by 1/2 or 3/4 teaspoon at a time.
Sorry about the goofy measurements - I've not an accurate means of measuring mass, nor anything less kitchen-ey for measuring volume
Many plates and films come with some mysterious pre-exposure or fog. Russian plates have notoriously, for me, turned black in development without any laser exposure at all.
I would always arrange a small part of the film to be shadowed, by the plateholder, a spot of tape, a shadow line, to have a reference area of emulsion which should develop clear, with no laser light hitting it. Arranging two spots, one with only reference, one with only object light, gives you an idea of exposure ratio. These developed gray areas must be judged before bleaching. You can rinse the plate of developer and turn on the lights, if you can't see well with your safelight. Yes, the spots will be image-free zones, but on the edge of a transmission master, no one will ever notice in the H2 print.
Otherwise, who knows what your "blue" plate means? Is it a recording of the light pattern? does it have diffraction lines from lens dirt or shadows? That would be good to see, at this point. Do you use a white card in the plateholder to preview what light is hitting the plate? Does the pattern match what is developed? Does the blue have a hot center, like the beam? If exposure is being recorded and developed, that part of your process is working - then vibration is probably the next area to tackle, the micro world, one fringe is not good enough.
Russian plates came in this fine heavy red/silver paper, plates packed in pairs, emulsion to emulsion, with spacers. When I used one plate, and left the other wrapped in the paper, the stored emulsion would eventually show a fold pattern of the red paper, as if the very paper they wrap the plates in exudes a desensitizing gas...
