May it is not a good test but here it is:
I actually like the oranfe filter the best.
It was shot with Ilford Delta 100.
PS: How many frames can I load in a 35mm capsule? I wonder if I can use it for travel loadinh the maximum I can
Kodachrome Professional 36 exposure rolls often had 38-39 exposures on them. Slides in my collection have numbers of 36, 37, 38 and 39.
Back to the filter question, always remember that filters don't lighten their own color, they hold back (thinner on the neg, darker on the print) other colors, holding back their opposite (or complementary) colors the most. Objects of their own color remain relatively unaffected. It's the application of the filter factor, increasing exposure, that make it's own color objects heavier on the negative, or lighter on the print, depending on how you decide to print.
It makes sense to me that the orange worked well for Marcio, as it has some yellow, related to green, so, not too extreme, but enough to enhance the value differences within the green leaves.
By the way. My filters are Cokin. I don't know about their quality but they are the ones I could afford.