Frank, Your works on the M3 is really amazing. After all these modification works, it would appear that with your thorough understanding of the machine, you can custom fit a large conical burr, like those 83mm ones, to the M3 to replace its flat burr. Apparently it could combine its convenience in d...

Did you also compare the environmental humidity when you did the benchmark roast? Have you darkened the drum surface intentionally or unintentionally afterwards? Did you clean M3's fan? Are you certain you had replicated the airflow speed in the different roasts you compared? (Not the fan knob setti...

With different drum, the heat transfer efficiency changed drastically and it basically became two different M3. If you apply same power to roast the same weight of green beans to aim at the same surface roast level or surface BT readings, the perforated drum would end the roast at least 1 to 2mins e...

pShoe, I thought in that common sense logic before. However, experimental results suggest the opposite. It seems the bean centre has another physical/chemical factors that are dominantly affecting how fast it got roasted. May be the steam pressure that's built up intra-cell. May be other things. But...

If your maragogype is from Hawaii, I suggest you better don't extend the drying phase due to its low density. It's fragile and I felt that they like faster roast instead of a long one

Tom, it could be that SM's roaster is having higher heat transfer efficiency than your M3 which makes their roasts having lower RD. With lower RD, the average roast degree of ground is darker despite bean surface may look the same color at the same measured BT. Of course it brews less acidic coffee ...

Just a thought, why nobody is making a physical gadget thing for iphone or other smart phones. A simple apps will do all the photo taking/flash light setting/resizing/color sampling etc

Yes, every roast. Even without an Agtron reader, you can still get readings of "RD", with a DIY system which should be good enough for your own comparison, given you are dedicated enough to take the trouble. Regarding the DIY roast level detecting system, figure out a setup which you can use consist...

It may not be better. It really depends on how you use the perforated drum. It's more like with the perforated drum, you can "Grill" the beans if you want, instead of just "Roasting" the beans. It makes more fun and would offer a larger variety in terms of roasting/grilling profile. However, with th...

Jim, I agree your point that we should use a "standard" profile when comparing cupping results. Otherwise, we aren't comparing anything meaningful. However, in real world, there's no "standard" unless we are using the same roaster with same setup under the same environmental condition. We often igno...