Errata and Compensating for 3D Print Tolerances

Here I show how to get the best optical performance from the PUMA open source 3D printed microscope by showing how to compensate for optical path length variations. These can occur due to inevitable 3D print height variations as well as a 1 mm design error (that has since been fixed in the CAD models as of 23 August 2022). I also take the opportunity to correct some demonstration errors from my prior videos.
CONTENTS
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00:08 Intro
00:30 The 1 mm undershoot error
02:06 How this error came about
04:32 How to correct for the 1 mm error
05:36 Error in the video on the trinocular camera port
06:28 Clarification for the video on Köhler illumination
07:48 How to correct for 3D printing errors
09:27 End of 'Phase 1' - where next?
This video marks the end of 'Phase 1' of the PUMA project - the phase where I detail how to build the scope in its original form with its optional modules as published in the 2021 Journal of Microscopy paper ( onlinelibrary.... ).
SUPPORT PUMA
============
PUMA is an open source microscopy project. You can help support the project by:
1. Become a Patron: / pumamicroscope
2. Donate via PayPal: www.paypal.com...
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4. Spread the word - post the news about PUMA and link to this RUclips channel on your social media sites and any other outreach method (tell your friends, colleagues, students or teachers and lecturers about PUMA, for example).
5. Consider purchasing your optics and related supplies from our affiliated online optics store, OptArc.co.uk ( www.optarc.co.uk/ )
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For the latest developments in the project subscribe to this RUclips channel and check out the 'Community' page here as well as following my on Twitter and, of course, the official PUMA GitHub page. Here are the links:
FOR FURTHER INFORMATION
=======================
1. Open access write-up about PUMA on the FreeCAD blog:
blog.freecad.o...
2. The official PUMA GitHub page where you can download the specs and source files to build or customise your own PUMA system:
github.com/Tad...
3. The scientific peer reviewed publication on PUMA that was published in 2021 in the Journal of Microscopy (a journal of the Royal Microscopical Society) available here:
pubmed.ncbi.nl...
onlinelibrary....

[@Natulxs]

I'm working on putting together a PUMA for my (hopefully) future research and was wondering if there are plans in the works for an "inversion" module?
Objectives being below the sample would go a long way toward increasing the use cases of the PUMA to encompass live-cell work, such as using cover-glass bottom dishes and even plastic culture flasks.

[@PUMAMicroscope]

Thanks for the question. Right now, the answer is no for an inverted module. I have thought about it - it would require a new stage and stand module and the stage is the single most complex module to build - but perhaps I could design it to use as much as possible of the original stage parts. I agree it would be good to have this option. Perhaps if there is a big enough demand I could return to that if someone else doesn't get there first. You may have noticed I have started to bring my PARDUS project out into the open (github.com/TadPath/PARDUS). I would like to make a PARDUS stage for the PUMA at some point so that might be a good opportunity to make an inverted stage module but nothing has been started. If your work involves only imaging (rather than direct vision) then you may find the OpenFlexure scope a better solution because it is an inverted scope (although they have made an upright version as well now) provided the limitations of their optical capabilities don't detract from your research goals.

[@Natulxs]

@@PUMAMicroscope I appreciate your work and understand if other parts of the project take priority but you can definitely toss me in as one for the "demand" column.
My use case would depend on fairly good optical capabilities as I will primarily be spot checking motile small (2uM by 5uM) parasites for expression of fluorescent fusion proteins after transfection, to decide whether to proceed with more detailed (and time consuming) super-resolution microscopy.
Thus the OpenFlexure microscope did not seem viable when I first looked into it.
My current lab uses the Zoe system from Biorad for this, which does and excellent job , but at 15kUSD that is a big chunk of change.... especially for a piece of equipment that will never be directly used to generate figure images.