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<body><div>I agree with Nikita, but independently from that, if the objective is infinity-corrected, it is possible to test a tube lens and its distance from camera by attaching a tube lens to the camera, taking it to a big room and trying to get a sharp image of something at the other end of the room (I was taking a photo of a reagent bottle trying to get the text on the label sharp...)</div><div><br></div><div>Regards,</div><div>Monika</div><div><br></div><div>W dniu .11.2016 o 01:53 Nikita Vladimirov <nvladimus@gmail.com> pisze:<br></div><br><blockquote style="margin: 0 0 0.80ex; border-left: #0000FF 2px solid; padding-left: 1ex"><div dir="ltr"><div><div><div>Hi, Matt,<br></div>The image seems to have really strong astigmatism, and the optical axis is way off center. The lens you use has f=25mm, it is a far cry from what the tube lens is expected to be, f=180 mm for Olympus objective. You cannot expect any decent quality from a tube lens which is so far from what the system design (objective - tube lens). You need a proper tube lens, or at least an achromat with similar focal distance to have a decent image quality. <br></div>Best,<br></div>Nikita<br><div><div><br><br></div></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Nov 16, 2016 at 11:52 AM, FORD Matthew <span dir="ltr"><<a href="mailto:Matthew.Ford@ed.ac.uk" target="_blank">Matthew.Ford@ed.ac.uk</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p>Hi OpenSPIMers,</p>
<p><br>
</p>
<p>I am in the process of building an open spim system based on the original open spim. I've tried to image some fluorescent beads but am seeing an odd effect where beads around the edge are being distored with the
<span>curvature </span>of the lens (I have attached an image). We are using a <b>
LA1951-A - N-BK7 Plano-Convex Lens</b> as a tube lens rather than the olympus U-TLU. I was wondering if the tube lens is what is causing the abborations but I am fairly new to optics so am not sure. If anyone has any advice on what might be causing the abborations
I would lvoe to hear your suggestions as I'm a bit stuck.</p>
<p><br>
</p>
<p>Thanks in advance for your advice,</p>
<p><br>
</p>
<p>Matt <br>
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</blockquote><br><br><br><div id="M2Signature"><div>-- </div><div>Dr Monika Pawłowska<br>Nencki Institute<br>02-093 Warsaw<br>Pasteura 3<br>Poland</div></div></body></html>