Yes, right. The curve is almost the same and I can imagine that the programmers made this choice, otherwise the machines without the IBTS will get useless. Perhaps they can make an option in the settings where the ROR is derived from: the IBTS or the beanprobe.
That would be nice, though I suspect whether or not it’s easy depends on a lot we don’t know about how the software (and possibly the firmware) are written. 
I believe that your thoughts could well be inline and from what I’ve read in Aillio articles, they have a lot of excitement about where IBTS could take them with their roasters. Maybe if they get it implemented well enough, it may be a business opportunity for them as an measurement option for other coffee-roasters in the industry. I’m reading my own tea-leaves a bit here, but who knows?
You can ask every programmer: this will not be a problem. Algorythm stays the same, only the data variables are different. And both data, IBTS and BT, are read from the bullet R1.
It would be nice to have ROR available for both readings and be able to disable them based on what IR sensor you have.
This and adding smoothing would be good enhancements.
Thinking about this some more, another factor that may have been behind leaving the ROR curve as-is and tied to the old temperature probe could be a desire not to introduce too many drastic changes to everyone’s processes at once. And, moving ROR to the IBTS curve would introduce one or two differences that are bound to affect a lot of people.
In switching to IBTS, the “turn” goes away. I’ve seen it argued (and myself believe) that the turn is less a real-thing-that-happens than it is an artifact of less accurate measurement tools. By itself, I’m not sure that’s a big deal but a downstream impact of the turn not going away is that initial ROR is going to drastically change. I know that when I asked for feedback on an initial batch I put through the bullet, some of the first suggestions I got involved shooting for a higher initial ROR. If there are a lot of people who are currently using that figure as a critical signpost in their batches, pulling it out from under them without time to get used to the idea isn’t going to be too well received. This way, folks who have built habits based on the behavior of more traditional temperature probes have time and space to correlate what they’ve always done to what’s different about IBTS for a while before just losing what might be an important early roast focus for them.
As for me, it wouldn’t bother me–this is the first gear I’ve owned that really lets me easily track and consider curve data, and I’m not too used to it yet. I can take that “your initial ROR should be 5 or 6 degrees higher” suggestion, abstract it to “bump up my power setting at the beginning” and be fine…
Yesterday, I ran across this information in the Bullet manual (top of page 17) and had missed it.
“Bullets with the IBTS (V1.5 & V2.0) will by default show the IBTS temperature as the
Bean Temp. The X-LED light above the A button will be ON when the temperature is
from the IBTS and OFF when displaying the bean probe temperature. By pressing the A
button you can toggle between the bean probe and the IBTS.”
That appears to say that if you have at least ver 1.5 we can select between IBTS or the Bean Probe reading for bean temp. I have not played with switching between the (2) sources, but am wondering if the ROR graph adjusts depending upon what bean temp source the user selects from the Bullet control panel?
I’m a fan of seeing “the turn” just as the indicator of when the beans are beginning to take on heat after charging.
I’ve played with the “A” button switching back and forth and I don’t recall seeing any change in the RoR graph. The reading just toggled back and forth to match either the bean temp or drum temp reading in RT. I just leave it on the IBTS reading now and pay little attention to the bean temp from the old probe.
This is for the roaster display and doesn’t affect anything in RoasTime. ROR is still based on the old Bean Temp probe and not the IR sensor.
Ok, thanks for the replies. I’ll hafta play with it myself (just for grins) when I wrap-up the last 2 “seasoning” roasts that I’ll be doing this weekend.
I suspect a lot of folks are, but an ROR that pulls data from a source that doesn’t have the turn is going to be a big change for folks who use it.
There’s also the potential for scaling issues there since the possible range of ROR values is going to be a lot wider. For grins, I went back to a curve I manually built when I was using my Gene that was based on periodically noting the temperature on its display. I intentionally picked one where I didn’t preheat, as that temperature curve then looks the most like a curve we’d get from the Bullet’s IBTS (I used Fahrenheit on the Gene):
Here’s an ROR plot for that roast. This is pretty well inline with what we could expect from an IBTS-based one:
The good news is, the early direction change could give folks who make use of “the turn” a reasonable proxy. The bad news is–besides a different peak value/range that users would need to internalize–that the more extreme changes early would make the ROR change later in the roast, where it’s arguably more important seem to plateau when it’s really not. I’m sure there are ways to manipulate the scale or the display to minimize that, but good luck building consensus on how that should look. 
I’m not sure I understand the significance of this. I went back and looked at numerous roasts from my Phoenix Oro, which I use Artisan exclusively, and the turn is auto marked in each one just past the one minute mark. RoR doesn’t even start to show until around the 1:30 mark. and it’s a vertical line until it peaks. I can tell on the Bullet when the turn takes place by watching the digital RoR change from negative to positive. Doesn’t affect my roast other than digital entertainment. Am I missing something here?
Honestly, I don’t think you are.
The point I was trying to make in my posts today was that, if Aillio made a wholesale change in the source data for ROR (from the traditional bean probe to the IBTS) the data at the beginning of a roast/around the turn would be different enough that it could throw off or upset users who are used to, or making decisions based off of, the way it reads now.
It’s a solve-able problem, and what I’m coming around to is I think just a better understanding of the non-technical complexities involved in making what seems like a simple technical change if that makes sense.
The turning point is mostly “graph entertainment” and not significant. Frankly, learning to roast on the Bullet without a PC connected at all would be what I’d recommend. That’s because in all my years of roasting and participating in forums, many times I’ve seen people get wrapped up in numbers and parroting things rather than have actual roasting knowledge that comes from just doing it themselves.
So for me, the RoasTime graph is mainly a visual representation of what I did during the roast using the Bullet’s front-panel data and checking the beans. I’m used to working with a count-up timer and actual bean temperature (via thermocouple) to know if I need to speed or slow a roast. I’ll glance at the graph mostly for visual entertainment while I’m waiting to make my next manual adjustment. 
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IBTS or not to IBTS? Answers? Questions! Questions? Answers! (quote: one of the instrumental songs of our famous Dutch group “Focus”).
In my search to prove the advantage of the IBTS, I roasted 500 and (yes, only) 200 grams of the same coffee. At the start it’s useless to compare the ROR-measurement of the IBTS and beanprobe (BT). But after the start (the more important part of the roast) the ROR between IBTS and beanprobe (BT) is almost the same from both roasts. Why did I ever purchased the IBTS as the ROR differs only slightly? See the graphs of the two roast below.
My friends of this wonderful machine, do we need an IBTS?
At first I would say no, but after taking a close look at the BT temperature and the IBTS (“drum”) temperature at the FC from both roasts, I would say yes. What would be your conclusion?
the end temps are different, guess the advantage is that the end temps are very similar doesn’t matter on bean weight. 200 gr is not enough due drum volume for this try min 300 350 and then compare to 500 gr or what ever.
In the future we will offer the additional ROR from the IBTS. We already have it running but want to improve the data before we release this. The data needs to run through a new prediction filter that we are not finished designing, otherwise the data will be too noisy. Not an easy task.
The benefits of the IBTS are many. Much much faster to react and consistent across all batch sizes.
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Hello Jacob, do we have any update regarding IBTS ROR? Can we rely on it now and ignore Bean Probe ROR? Here is my recent roast. As far as I can see, there is not much noise in the data. Please confirm. Thanks!
Hi. I think the I-ROR is pretty good yeah.