One thing to remember is that the "pastel" gene is a reduction of black. Color has been a byproduct with this gene. So, yes, Ronne pastels will make better looking albinos.
And, you are correct. All pastels are not created equal. Within Ronne's line of pastels you will see many variences. Most will have that reduction of black. Some, will be more colorful than others. So, there are variences within the line. I have seen some people call their animals a pastel......Yet it was not. Not to say that there are not "Pastels" out there. There are. But, buyer beware.
The Ronne Pastels that I bought from him just keep getting better and better with age. The Lucy line that I bought are very clean and are turning out to be quite colorful.
I am pretty anal about lines and their origionalters. So, I will give you my "anal retentive" answer. LOL!
To get an Ivory you would need to breed a Ronne Pastel to an anery boa. Most.....Or half of the siblings would have the pastel trait. (Reduction of black) You would need to then grow those babies up and breed them together to get Ivories. How many would be Ivories? I would have to say most, if not all of them. My reasoning for this is the fact that you are breeding two pastel het anerys togethers to make the Ivories. The pastel gene would be very present within most, if not all of the siblings. The pastel gene has never been called co-dominant. But, if pretty much acts in that way.
Hope this helps,
John
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"To be the best..........You must lose your mind."