Solarplate: exposure for aquatint vs exposure for image

[annie75]

Hi everyone this is my first post on this site!
I am a fine arts student in NZ. I have been experimenting with photopolymer techniques, the most successful one being Solarplate. I am refining my technique with it currently and wonder if anyone has advice on the time ratio between aquatint ( I am using Weldons one) and image??
I made a very detailed plate today with equal exposure time for aquatint and image. The only problem was that the image was tonally flat, no rich shadow.
I imagine that if I change the ratio, I will get better contrast. I have mainly heard of the aquatint exposure being shorter than the image exposure, but tonight read something to the contrary.
Any advice?
Thanks

 

[clay]

If you have no shadow depth, you probably need to drop the screen exposure relative to the image exposure. I use Toyobo KM73 plates and the ratio usually runs about 1 : 1.2 (screen : image)

 

[annie75]

Thanks for that! I will give it a go today. I am working with sunlight and the skies are a stormy grey- wish me luck!