I`m not like most people answering your post here, meaning that some of the folks are extremely experienced on playing the bass with a bow and are kind, tolerate, and even serious enough to post photos of their own bowholds for you as a reference. However, what were you thinking about when asking about a ghetto grip of a beginner from people with deep knowledge about how`s and why`s and the tradition and THE MUSIC behind it all? Like everybody else, I suggest you to get a teacher and dive into the reasons why there`s plenty of approaches about the bowhold. Anyway, it looks like you`re allready more into a german bow, get one and a good teacher, whatever is the price tag. It will propably save you from some physical pain and lots of time-wasting.
Anyway, as it is about traditions and such, there`s propably someone with carpal tunnel syndrome suggesting the exact technique that got them into their CTS. No-one here knows about the sound you`re aiming at, or how you feel when you`re trying to get there, or how you`re physically " constructed ". It`s not like these folks just kept on believing in how they were schooled regardless of how they felt, but it all is a process that goes on as one grows with the instrument and the culture around it, and we all get old while at it.
I try to hold my german bow the way that gets me the sound without hurting. With that said, I have two great teachers who pushes me to certain directions with very reasoned motivation. The only valuable information physically is to do ÉVERYTHING AS RELAXED AS POSSIBLE. And it`s not allways like that when you try to be as loud as possible acoustic in a ensemble with drums, horns and electric guitars, for example. Arco is a demanding MF, whatever is where you want to go musically.
A whole another story is orchestral playing, you need some kind of a reliable concept to execute all the finesse that THE MUSIC REQUIRES. It`s not about you anymore, it`s about the section, the whole band, the music. And while this has been going on for some centuries, there`s plenty of knowhow about how to execute it all, and the way it got to the point where it is now. It`s no black magic at all, it`s how to work thru the music and how to express it with that bow in your hand. We all need to know about it, regardless of what we play with the bow and if we were doing it at all at any point. That`s just where all the valuable information is coming from, the home base. It`s not like stuff wouldn`t grow without that information, but it`s 2018 and it`s all around us nowadays. You took the first step asking here, so why not go further?
Hope this makes any sense, and great luck for your journey!
R