Yeast starter/ washing question

[max_h]

Just brewed my second AG batch(have brewed lots of partial). For my first AG batch I used some English Ale yeast I got from my local Brewpub. About a serving spoons worth- just dumped it in, no starter, no idea what the cell count/pitch rate would be.
When I bottled that batch, I washed about a large serving spoon of the yeast in the bottom of the fermenter (I didn't use a secondary) according to the sticky on this site. Fast forward 6 weeks, I brought the two small mason jars of washed yeast to room temp and dumped them in my wort, again no starter. I was nervous and thought I made a big mistake not using a starter but after 48 hours they went to work and are now vigorously churning away.

So here's my question, I plan to wash and re-use this batch of yeast, this time I will make a starter. I wouldn't know where to begin to measure cell count/ pitch rate etc and should I be concerned or should I just be dumping yeast without understanding how to gauge my cel count essentially just "eyeballing it" and if not how can these things be measured when you start with a unspecified amount of trub? Maybe Im reading too much into it and I should just RDWHAHB?
Hope this question makes sense
Max

 

[porterpounder]

Check out the Mr. Malty yeast calculator. It gives your the ability to estimate your counts by eyeballing how dense the slurry is and how old it is.
www.mrmalty.com

 

[WoodlandBrew]

The Mr. Malty calculator is pretty good but under estimates viability in my experience. 1-2 billion cells per ml of settled slurry is normally safe estimate. (plenty more details on my blog or in my book if you are interested)

 

[max_h]

1-2 billion cells per ml of settled slurry is normally safe estimate.

That's exactly what I was looking for, a basic way to eyeball cell count.

Now if I could convert approximate ml to amount spread over the surface of a small mason jar, I could get close enough in the ballpark.

example: If I have 1/4" of washed yeast slurry in the bottom of a 3" mason jar I could estimate it to equal 12 ml (wild guess for the purpose of discussion)so 180 billion yeast cells in each jar?

Much thanks!

 

[WoodlandBrew]

The way I estimate the content of a mason jar is to pour water into a similar sized jar and then measure that volume.