You are correct. I’ve not looked closely at the this. I will have a look at where the LLD and Z-positions are linked.
If I could do things over, I’d have gone with a couple Singer PIXLs instead of a QPix. As long as you don’t need QTrays, you could buy 2-3 instruments for less than the cost of a QPix (~300k+) and achieve the same throughput based on some napkin math. The folks at Singer were great when I chatted with them both in some demo calls and at SLAS.
Uneven Agar is not a problem for the Singer PIXL - It uses very precise pressure sensors to detect the surface of the Agar/Colonies. Additionally, you can easily set the length of the PickUp line so that if your working with a particularly squishy sample, you can guarantee it wont contaminate the feed head. Hope that helps! - Full disclosure, I work for Singer Instruments! - Edward
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hi everyone, I was talking to a colleague and they want to automate picking from big bioassay plates 245x245. I told them that to my knowledge there is no colony picker that can pick from these. But i thought to ask just in case..
I would contact SciRobotics. I don’t see why they couldn’t pick from something that large as long as it fits within the field of vision of the camera. It’d be a custom labware and you wouldn’t be able to move it around with a Tecan RoMa, but otherwise it’d probably be OK.
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thank you for the response, I do not have a tecan in my current post, however the plan is to get a hamilton and equip it with the easypick module. One issue though is the light table? Do you think that’d be an issue?
I have used pickolo on our evo in a previous job. I liked it!
I’d say the light table is a bigger issue than the size of the plate. You can always, for example on a STAR, put several small plates on a deck layout to cover the entirety of the real, big plate. However, having a big enough light source that will evenly illuminate a big plate is a different thing. You might actually need to head to your local arts and crafts supplier to get a light table they use for tracing 
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Hey! I have a question, can the EasyPick pick colonies from 245mm x 245mm Bioassay plates?
Hi @robolabrat,
Yes, there is an XL light table available that supports the large format petri dishes. This has additional reference points that the camera channel uses to take several images of various sections of the plate (the field of view of the camera at the supported working distances does not cover the entire plate in a single image), which easyPick software stitches into a single image with all pixels mapped to calibrated deck coordinates.
The standard light table supports both 90mm round petri dishes, as well as SBS petri trays.
Thanks.
-Nick
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Hi Nick thanks for your response. When you say large format petri dishes you mean larger diameter round ones or the square plates, bioassay plates. Like these ones: Thermo Scientific Nunc Square BioAssay Dishes 25 mm | Buy Online | Thermo Scientific™ | Fisher Scientific
Can one have a light table that accomodates these? Since the capability to stitch images is there, it should be possible? one would need a custom light table for this I assume, right? Does hamilton support that?
Out of curiosity — are you locked into those 245 × 245 bioassay plates, or is there some flexibility on format?
The reason I ask is that a lot of the colony picking workflows I’ve seen tend to standardise around either:
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90 or 140 mm round plates
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or SBS-format agar plates such as Singer PlusPlates
Mainly because once you get into the really large square formats, things like illumination and imaging consistency start to become the limiting factor rather than the picking itself. Even with stitching approaches, you can end up fighting gradients, edge artefacts, etc.
If there is flexibility on plate format, it can open up quite a few more options (and usually simplifies the workflow quite a bit).
Also worth noting — the imaging side of colony picking has moved on quite a bit recently. Our newest system (PIXL Max) uses more advanced detection approaches (AI/ML - based classifications rather than just thresholding), which helps a lot with:
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irregular or unusual colonies
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merged/satellite colonies
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variability in agar or lighting
That’s been particularly useful in applications where morphology actually matters, rather than just picking the biggest/roundest colony.
So I guess the key question is: is the plate format driven by the biology/assay, or is it more of a legacy workflow choice?
Thank you very much for your response. So, the bioassay plates are just personal preference/ legacy workflow from one of our colleagues.. I tried my best to convice them in using SBS trays but wasn’t succesful.. So yes, we’re stuck with few options. The other issue is that we really only do basic white E. Coli colony picking (cloning applications), so buying a dedicated colony picker, is an overkill. Dedicated colony pickers like the PIXL are amazing, very capable, but we would be wasting them in our lab… Think of it as buying a really amazing and capable off roader, simply to drive a 10km paved road to the grocery store and back… Waste of potential.
Having a big liquid handler (like a STAR) that also has a colony picking module, really saves us money and also adds capabilities to our general auatomation suite, which is missing a large deck.
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