SRM Meter

[ajdelange]

I got one of those little Arduino Starter Kits a few days ago and before I knew it I had a functioning SRM meter in front of me. "Functioning" means that a breadboard reads the "SRM" of a neutral density filter reasonably accurately. The reason for the post is to ask whether you guys would have any interest in having such a thing. If so, how much would you be willing to pay for it? How accurate would you want it to be? Would you want it as a completed project? A kit? etc.

I have no idea as to what I might want to do with this but before I make any plans I need to check out how accurate I can get it for reasonable cost.

 

[boydster]

I think this is a cool idea. Subscribing even though I don't have much to add... but I'd prefer a kit I think. Accuracy would have to be sufficient to justify whatever the price ends up being - obviously it wouldn't make much sense to go out and spend $50 (just throwing a number out there) for a piece of equipment that doesn't do better than just my eyes alone. I'd say +/-10% from actual SRM would be a nice target. But I haven't a clue as to how reasonable a task that is to achieve.

 

[ajdelange]

I figured $50 would be a resistance point and I'm not sure it can be done for less than that.

One question that I forgot to mention in the original post has to do with preference for a self contained unit. If users were willing to plug the thing into the USB ports on their laptops the answers can be printed by any application which can receive and display a serial string over USB (which would also power it and take away the need for a battery or other power supply). Most significantly, this obviates the need for an LCD display which is one of the most expensive individual components. Though suitable display panels (with driving hardware) are only about $15 that's an appreciable part of $50.

Thoughts on having to tether to a laptop?

 

[303Dan]

I would be interested in a completed project with accuracy in the +\- 0.5 range at worst. $50 seems like a reasonable price point if it's doable for that price. To me, USB power would be just fine.

 

[boydster]

Tethered seems fine to me, too

 

[CadiBrewer]

I'd be interested in a kit format. I wouldn't mind if it had to be tethered and would welcome having it use a Raspberry Pi or laptop as the interface.

 

[PlinyTheMiddleAged]

Count me in too. I think I'd prefer tethered to a computer to keep the cost down. Seems like a fair compromise.