Is field of view of objective constrained by field number of microscope?
Locked
 
|
Shalin Mehta |
Is field of view of objective constrained by field number of microscope?
|
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hello, I have a question about the maximum usable field of view of commercial objectives, if the only constraint is the mostly-flat field of view. We would like to find a commercial low mag, high NA objective and extract as much field of view as possible. Is the usable field of view of an objective constrained by the field number of the microscope? i.e., if the field number of the microscope is 26 mm, is the diameter of the field of view constrained to 26mm/mag of the objective? Are there stops in the objective that enforce this specification? If we are to use a tube lens of same focal length as the commercial microscope, but larger diameter, can we have a field of view larger than specified by the field number? Having a flat field of view will be great, but slight imperfection is not a problem. Thanks Shalin |
|
|
Kurt Thorn |
Re: Is field of view of objective constrained by field number of microscope?
|
|
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hi Shalin - I've done some qualitative investigations of this on our microscopes, and you can access information beyond the nominal field number of the microscope. The vignetting seems to mostly occur in the C-mount and camera adapter, so if you remove these you can get a bigger image. See http://nic.ucsf.edu/blog/?p=108 for some details. However, there's no guarantee what the performance of the objective beyond the nominal field number will be. In particular, the NA may be lower, there may be problems with field curvature and there will likely be aberrations. In fact, even at the periphery of the nominal objective FOV the point spread functions are more aberrated - see http://nic.ucsf.edu/blog/?p=770 I hope that helps. Kurt On 2/28/2014 9:22 AM, Shalin Mehta wrote: > ***** > To join, leave or search the confocal microscopy listserv, go to: > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > ***** > > Hello, > > I have a question about the maximum usable field of view of commercial > objectives, if the only constraint is the mostly-flat field of view. > We would like to find a commercial low mag, high NA objective and > extract as much field of view as possible. > > Is the usable field of view of an objective constrained by the field > number of the microscope? i.e., if the field number of the microscope > is 26 mm, is the diameter of the field of view constrained to 26mm/mag > of the objective? > > Are there stops in the objective that enforce this specification? If > we are to use a tube lens of same focal length as the commercial > microscope, but larger diameter, can we have a field of view larger > than specified by the field number? Having a flat field of view will > be great, but slight imperfection is not a problem. > > Thanks > Shalin > > -- Kurt Thorn Director, Nikon Imaging Center http://nic.ucsf.edu/blog/ |
|
|
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** I may be missing something here but I thought the field number was largely a property of the eyepiece. A WF eyepiece uses a field lens to reduce the final magnification a bit but in the process substantially increase the FOV. Of course the actual diameter of the tube has to allow this and that is why most manufacturers went to 25mm lens mounts rather than RMS when they went to infinity correction. In this regard the old East German Zeiss lenses were better than the West German ones. But of course after German reunification the West German company could not possibly accept that the East German company actually did some things better. Guy Guy Cox, Honorary Associate Professor School of Medical Sciences Australian Centre for Microscopy and Microanalysis, Madsen, F09, University of Sydney, NSW 2006 -----Original Message----- From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Kurt Thorn Sent: Saturday, 1 March 2014 5:39 AM To: [hidden email] Subject: Re: Is field of view of objective constrained by field number of microscope? ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hi Shalin - I've done some qualitative investigations of this on our microscopes, and you can access information beyond the nominal field number of the microscope. The vignetting seems to mostly occur in the C-mount and camera adapter, so if you remove these you can get a bigger image. See http://nic.ucsf.edu/blog/?p=108 for some details. However, there's no guarantee what the performance of the objective beyond the nominal field number will be. In particular, the NA may be lower, there may be problems with field curvature and there will likely be aberrations. In fact, even at the periphery of the nominal objective FOV the point spread functions are more aberrated - see http://nic.ucsf.edu/blog/?p=770 I hope that helps. Kurt On 2/28/2014 9:22 AM, Shalin Mehta wrote: > ***** > To join, leave or search the confocal microscopy listserv, go to: > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > ***** > > Hello, > > I have a question about the maximum usable field of view of commercial > objectives, if the only constraint is the mostly-flat field of view. > We would like to find a commercial low mag, high NA objective and > extract as much field of view as possible. > > Is the usable field of view of an objective constrained by the field > number of the microscope? i.e., if the field number of the microscope > is 26 mm, is the diameter of the field of view constrained to 26mm/mag > of the objective? > > Are there stops in the objective that enforce this specification? If > we are to use a tube lens of same focal length as the commercial > microscope, but larger diameter, can we have a field of view larger > than specified by the field number? Having a flat field of view will > be great, but slight imperfection is not a problem. > > Thanks > Shalin > > -- Kurt Thorn Director, Nikon Imaging Center http://nic.ucsf.edu/blog/ |
|
|
Eric Laloum |
Re: Is field of view of objective constrained by field number of microscope?
|
|
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** One point raised by Guy Cox left unanswered, regarding factors affecting field number. To my understanding field number is mostly linked to the objective lens and maybe constrained by microscope, but is not related to the eyepiece. For instance, in the cases where we need to estimate irradiance onto the sample (photons / sec / m²) in wide-field epi-fluorescence microscopy ; we need to divide total light power on sample plane (as measured by power meter) by illuminated area ; and the illuminated area is calculated with objective field number (and magnification). It's just my own guess and I haven't investigated it furher, so don't hesitate to comment t correct ... Eric Laloum Paris ----- Mail original ----- De: "Guy Cox" <[hidden email]> À: [hidden email] Envoyé: Samedi 1 Mars 2014 12:40:29 Objet: Re: Is field of view of objective constrained by field number of microscope? ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** I may be missing something here but I thought the field number was largely a property of the eyepiece. A WF eyepiece uses a field lens to reduce the final magnification a bit but in the process substantially increase the FOV. Of course the actual diameter of the tube has to allow this and that is why most manufacturers went to 25mm lens mounts rather than RMS when they went to infinity correction. In this regard the old East German Zeiss lenses were better than the West German ones. But of course after German reunification the West German company could not possibly accept that the East German company actually did some things better. Guy Guy Cox, Honorary Associate Professor School of Medical Sciences Australian Centre for Microscopy and Microanalysis, Madsen, F09, University of Sydney, NSW 2006 -----Original Message----- From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Kurt Thorn Sent: Saturday, 1 March 2014 5:39 AM To: [hidden email] Subject: Re: Is field of view of objective constrained by field number of microscope? ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hi Shalin - I've done some qualitative investigations of this on our microscopes, and you can access information beyond the nominal field number of the microscope. The vignetting seems to mostly occur in the C-mount and camera adapter, so if you remove these you can get a bigger image. See http://nic.ucsf.edu/blog/?p=108 for some details. However, there's no guarantee what the performance of the objective beyond the nominal field number will be. In particular, the NA may be lower, there may be problems with field curvature and there will likely be aberrations. In fact, even at the periphery of the nominal objective FOV the point spread functions are more aberrated - see http://nic.ucsf.edu/blog/?p=770 I hope that helps. Kurt On 2/28/2014 9:22 AM, Shalin Mehta wrote: > ***** > To join, leave or search the confocal microscopy listserv, go to: > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > ***** > > Hello, > > I have a question about the maximum usable field of view of commercial > objectives, if the only constraint is the mostly-flat field of view. > We would like to find a commercial low mag, high NA objective and > extract as much field of view as possible. > > Is the usable field of view of an objective constrained by the field > number of the microscope? i.e., if the field number of the microscope > is 26 mm, is the diameter of the field of view constrained to 26mm/mag > of the objective? > > Are there stops in the objective that enforce this specification? If > we are to use a tube lens of same focal length as the commercial > microscope, but larger diameter, can we have a field of view larger > than specified by the field number? Having a flat field of view will > be great, but slight imperfection is not a problem. > > Thanks > Shalin > > -- Kurt Thorn Director, Nikon Imaging Center http://nic.ucsf.edu/blog/ |
|
|
lechristophe |
Re: Is field of view of objective constrained by field number of microscope?
|
|
In reply to this post by Shalin Mehta
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hi Shalin, Maybe there is also a possibility to use a camera with less, bigger pixels and use a "super-resolution" method : take several images with small (sub-pixels) shifts and reconstruct an image with more, smaller pixels. I think this was used in certain Zeiss cameras a few years ago (but I couldn't find a link or reference just yet). Best Regards, Christophe 2014-02-28 18:22 GMT+01:00 Shalin Mehta <[hidden email]>: > ***** > To join, leave or search the confocal microscopy listserv, go to: > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > ***** > > Hello, > > I have a question about the maximum usable field of view of commercial > objectives, if the only constraint is the mostly-flat field of view. > We would like to find a commercial low mag, high NA objective and > extract as much field of view as possible. > > Is the usable field of view of an objective constrained by the field > number of the microscope? i.e., if the field number of the microscope > is 26 mm, is the diameter of the field of view constrained to 26mm/mag > of the objective? > > Are there stops in the objective that enforce this specification? If > we are to use a tube lens of same focal length as the commercial > microscope, but larger diameter, can we have a field of view larger > than specified by the field number? Having a flat field of view will > be great, but slight imperfection is not a problem. > > Thanks > Shalin > |
|
|
In reply to this post by Eric Laloum
Not for the first time, I wish we could post diagrams to the list! What Eric says is obviously correct about the area we illuminate. But illuminating an area doesn't mean that we can see it. In transmission microscopy we are accustomed to setting the field diaphragm to make the illuminated area match the visible area. A high-class epifluorescence system will let us do exactly the same thing. We tend to be slack about this since (unlike the transmission case) the illumination is automatically in focus so resolution is not affected. Can I suggest to Eric (and anyone else who wants to get to grips with such issues) that he takes a simple, cheap, student microscope and swaps through all the available eyepieces without changing anything else? That way he will understand how an eyepiece determines the field of view.
Guy Guy Cox, Honorary Associate Professor School of Medical Sciences Australian Centre for Microscopy and Microanalysis, Madsen, F09, University of Sydney, NSW 2006 -----Original Message----- From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Eric Laloum Sent: Wednesday, 5 March 2014 7:09 PM To: [hidden email] Subject: Re: Is field of view of objective constrained by field number of microscope? ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** One point raised by Guy Cox left unanswered, regarding factors affecting field number. To my understanding field number is mostly linked to the objective lens and maybe constrained by microscope, but is not related to the eyepiece. For instance, in the cases where we need to estimate irradiance onto the sample (photons / sec / m²) in wide-field epi-fluorescence microscopy ; we need to divide total light power on sample plane (as measured by power meter) by illuminated area ; and the illuminated area is calculated with objective field number (and magnification). It's just my own guess and I haven't investigated it furher, so don't hesitate to comment t correct ... Eric Laloum Paris ----- Mail original ----- De: "Guy Cox" <[hidden email]> À: [hidden email] Envoyé: Samedi 1 Mars 2014 12:40:29 Objet: Re: Is field of view of objective constrained by field number of microscope? ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** I may be missing something here but I thought the field number was largely a property of the eyepiece. A WF eyepiece uses a field lens to reduce the final magnification a bit but in the process substantially increase the FOV. Of course the actual diameter of the tube has to allow this and that is why most manufacturers went to 25mm lens mounts rather than RMS when they went to infinity correction. In this regard the old East German Zeiss lenses were better than the West German ones. But of course after German reunification the West German company could not possibly accept that the East German company actually did some things better. Guy Guy Cox, Honorary Associate Professor School of Medical Sciences Australian Centre for Microscopy and Microanalysis, Madsen, F09, University of Sydney, NSW 2006 -----Original Message----- From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Kurt Thorn Sent: Saturday, 1 March 2014 5:39 AM To: [hidden email] Subject: Re: Is field of view of objective constrained by field number of microscope? ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hi Shalin - I've done some qualitative investigations of this on our microscopes, and you can access information beyond the nominal field number of the microscope. The vignetting seems to mostly occur in the C-mount and camera adapter, so if you remove these you can get a bigger image. See http://nic.ucsf.edu/blog/?p=108 for some details. However, there's no guarantee what the performance of the objective beyond the nominal field number will be. In particular, the NA may be lower, there may be problems with field curvature and there will likely be aberrations. In fact, even at the periphery of the nominal objective FOV the point spread functions are more aberrated - see http://nic.ucsf.edu/blog/?p=770 I hope that helps. Kurt On 2/28/2014 9:22 AM, Shalin Mehta wrote: > ***** > To join, leave or search the confocal microscopy listserv, go to: > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > ***** > > Hello, > > I have a question about the maximum usable field of view of commercial > objectives, if the only constraint is the mostly-flat field of view. > We would like to find a commercial low mag, high NA objective and > extract as much field of view as possible. > > Is the usable field of view of an objective constrained by the field > number of the microscope? i.e., if the field number of the microscope > is 26 mm, is the diameter of the field of view constrained to 26mm/mag > of the objective? > > Are there stops in the objective that enforce this specification? If > we are to use a tube lens of same focal length as the commercial > microscope, but larger diameter, can we have a field of view larger > than specified by the field number? Having a flat field of view will > be great, but slight imperfection is not a problem. > > Thanks > Shalin > > -- Kurt Thorn Director, Nikon Imaging Center http://nic.ucsf.edu/blog/ |
|
|
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hmm, Guy, what about this? Popped up on a quick search: http://awwapp.com/draw.html#50542999 Not a direct post, but enough for a simple diagram! Avi On Wed, Mar 5, 2014 at 1:09 PM, Guy Cox <[hidden email]> wrote: > Not for the first time, I wish we could post diagrams to the list! > > Guy > > Guy Cox, Honorary Associate Professor > School of Medical Sciences > > |
|
|
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** But, Avi, I don't want to have to draw it! I want to post diagrams from my lecture notes. Guy Guy Cox, Honorary Associate Professor School of Medical Sciences Australian Centre for Microscopy and Microanalysis, Madsen, F09, University of Sydney, NSW 2006 -----Original Message----- From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Avi Jacob Sent: Thursday, 6 March 2014 4:42 PM To: [hidden email] Subject: Re: Is field of view of objective constrained by field number of microscope? ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hmm, Guy, what about this? Popped up on a quick search: http://awwapp.com/draw.html#50542999 Not a direct post, but enough for a simple diagram! Avi On Wed, Mar 5, 2014 at 1:09 PM, Guy Cox <[hidden email]> wrote: > Not for the first time, I wish we could post diagrams to the list! > > Guy > > Guy Cox, Honorary Associate Professor > School of Medical Sciences > > |
|
|
Jeff Reece |
Re: Is field of view of objective constrained by field number of microscope?
|
|
Have you tried Google Drive? Free, painless.
http: ***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** Hello Guy, Have you tried Google Drive? Free, painless. http://www.google.com/drive/storage.html Cheers, Jeff >________________________________ > From: Guy Cox <[hidden email]> >To: [hidden email] >Sent: Thursday, March 6, 2014 1:37 AM >Subject: Re: Is field of view of objective constrained by field number of microscope? > > >***** >To join, leave or search the confocal microscopy listserv, go to: >http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy >***** > >But, Avi, I don't want to have to draw it! I want to post diagrams from my lecture notes. > > Guy > >Guy Cox, Honorary Associate Professor >School of Medical Sciences > >Australian Centre for Microscopy and Microanalysis, >Madsen, F09, University of Sydney, NSW 2006 > >-----Original Message----- >From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Avi Jacob >Sent: Thursday, 6 March 2014 4:42 PM >To: [hidden email] >Subject: Re: Is field of view of objective constrained by field number of microscope? > >***** >To join, leave or search the confocal microscopy listserv, go to: >http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy >***** > >Hmm, Guy, what about this? >Popped up on a quick search: >http://awwapp.com/draw.html#50542999 >Not a direct post, but enough for a simple diagram! > >Avi > > > > >On Wed, Mar 5, 2014 at 1:09 PM, Guy Cox <[hidden email]> wrote: > > >> Not for the first time, I wish we could post diagrams to the list! >> >> Guy >> >> Guy Cox, Honorary Associate Professor >> School of Medical Sciences >> >> > > |
|
|
Craig Brideau |
Re: Is field of view of objective constrained by field number of microscope?
|
|
*****
To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy ***** The whiteboard thing seems simple for collaboration on a sketch, but pasting would be faster for quick demonstration purposes. Craig On Thu, Mar 6, 2014 at 5:22 AM, Jeff Reece <[hidden email]> wrote: > Have you tried Google Drive? Free, painless. > http: > ***** > To join, leave or search the confocal microscopy listserv, go to: > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > ***** > > Hello Guy, > > Have you tried Google Drive? Free, painless. > http://www.google.com/drive/storage.html > > Cheers, > Jeff > > > > > >________________________________ > > From: Guy Cox <[hidden email]> > >To: [hidden email] > >Sent: Thursday, March 6, 2014 1:37 AM > >Subject: Re: Is field of view of objective constrained by field number of > microscope? > > > > > >***** > >To join, leave or search the confocal microscopy listserv, go to: > >http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > >***** > > > >But, Avi, I don't want to have to draw it! I want to post diagrams from > my lecture notes. > > > > Guy > > > >Guy Cox, Honorary Associate Professor > >School of Medical Sciences > > > >Australian Centre for Microscopy and Microanalysis, > >Madsen, F09, University of Sydney, NSW 2006 > > > >-----Original Message----- > >From: Confocal Microscopy List [mailto:[hidden email]] > On Behalf Of Avi Jacob > >Sent: Thursday, 6 March 2014 4:42 PM > >To: [hidden email] > >Subject: Re: Is field of view of objective constrained by field number of > microscope? > > > >***** > >To join, leave or search the confocal microscopy listserv, go to: > >http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy > >***** > > > >Hmm, Guy, what about this? > >Popped up on a quick search: > >http://awwapp.com/draw.html#50542999 > >Not a direct post, but enough for a simple diagram! > > > >Avi > > > > > > > > > >On Wed, Mar 5, 2014 at 1:09 PM, Guy Cox <[hidden email]> wrote: > > > > > >> Not for the first time, I wish we could post diagrams to the list! > >> > >> Guy > >> > >> Guy Cox, Honorary Associate Professor > >> School of Medical Sciences > >> > >> > > > > > |
«
Return to Confocal Microscopy List
|
1 view|%1 views
| Free forum by Nabble | Edit this page |