Converting Yarn Weight to Hook Size

Hello!

In a crochet pattern (Dieter, the Ray), the eyes are crocheted using 100 m/50 g of yarn with a size 3 hook. I have yarn with a length of 125 m per 50 g. Can I achieve the same eye size using the 125 m yarn and a larger hook, following the pattern? How large would the hook need to be?
The entire ray is crocheted using 100m/100g of yarn and a size 4.5 hook. If I were to crochet it with a size 3.0 hook and make the eyes with my 125m yarn and a size 2.0 or 2.5 hook, would the proportions be correct? Are there conversion charts for “problems” like this?
I’m a beginner, so sorry if the question seems a bit odd ;-)

Good morning—it’s best to contact the author directly.

You can find her contact information in the Schneckenkind shop. She’s the best person to tell you if it will work.