http://confocal-microscopy-list.275.s1.nabble.com/Are-lower-magnification-objectives-brighter-tp7592013p7592025.html
That's fantastic, Craig! Kudos to you and Pina - this has become an essential tool in my toolkit (no commercial interest!). I'm sure Pina has mentioned it to me before that the two of you had a hand in this design but I had forgotten.
Subject: Re: [External] Re: EXT: Re: Are lower magnification objectives brighter?
> the oil objective. The highest angle rays may not hit the sensor -
Pina Colarruso and I actually helped Thorlabs develop that power meter, and our big contribution to the design was ensuring it does, in fact, take into account the high angle rays. There is a thin layer of index matching material underneath the glass window that eases the high-angle light into the silicone detector (*n* = 3 !!!) underneath the window. You can test this yourself by measuring a high NA oil lens with and without oil on the sensor.
Dr. Colarruso and I also recently got roped into volunteered to take part in the QUAREP microscopy initiative for repeatably quantifying microscope outputs among different systems. Working Group 1 revolves around power measurements and a very patient Thorlabs engineer has helped explain some of the fundamentals of the sensor to the group.
>
> Cheers,
> James
>
> -----------------------------------------------
> James Jonkman, Staff Scientist
> Advanced Optical Microscopy Facility (AOMF)
> and Wright Cell Imaging Facility (WCIF)
> University Health Network
> MaRS, PMCRT tower, 101 College St., Room 15-305
> Toronto, ON, CANADA M5G 1L7
>
[hidden email] Tel: 416-581-8593
>
http://www.aomf.ca>
>
> -----Original Message-----
> From: Confocal Microscopy List
> [mailto:
[hidden email]]
> On Behalf Of Model, Michael
> Sent: Tuesday, March 23, 2021 9:11 AM
> To:
[hidden email]
> Subject: [External] Re: EXT: Re: Are lower magnification objectives
> brighter?
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
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>
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> [lists[.]umn[.]edu] Post images on
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>
> James,
>
> Since you mentioned transmission bright-field, it is also a widely
> misunderstood topic because brightness is determined mostly by direct
> light from the condenser and not by diffracted light, so NA of the
> objective does not matter at al as long as it is larger than NA of the
> condenser. In other words, brightness is determined by the smallest NA
> between the objective and condenser. This can be easily verified using
> an objective with variable NA. Misstatements on this subject can be
> found even in some of the classical treatises.
>
> Mike
>
> -----Original Message-----
> From: Confocal Microscopy List <
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> Behalf Of MICROSCOPIA IBIS
> Sent: Monday, March 22, 2021 4:03 PM
> To:
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> Subject: EXT: Re: Are lower magnification objectives brighter?
>
> *****
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>
> Hi Craig.
> I wonder your drastical decrease power in your Argon laser in 514 line
> respect to 488 one. We had similar problem in one of the Ar laser we
> had with warranty and they had to change the laser. The power of 514
> nm line has not to be too small than the 488, I think (
>
https://urldefense.com/v3/__https://nam11.safelinks.protection.outlook> .com/?url=https*3A*2F*2Fwww.researchgate.net*2Fpublication*2F23485392_
> Design_and_implementation_of_a_sensitive_high-resolution_nonlinear_spe
> ctral_imaging_microscope*2Ffigures*3Flo*3D1&data=04*7C01*7Cmmodel*
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> 26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1Jx28NQ6x$
> [nam11[.]safelinks[.]protection[.]outlook[.]com])
> [
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> Design_and_implementation_of_a_sensitive_high-resolution_nonlinear_spe
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> 40KENT.EDU*7Ca9523323a2384461a25508d8ed6d8bd0*7Ce5a06f4a1ec44d018f73e7
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> [nam11[.]safelinks[.]protection[.]outlook[.]com]>
> (PDF) Design and implementation of a sensitive high-resolution
> nonlinear spectral imaging microscope<
>
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> PDF | Live tissue nonlinear microscopy based on multiphoton
> autofluorescence and second harmonic emission originating from
> endogenous fluorophores and... | Find, read and cite all the research
> you need on ResearchGate
>
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> Regards,
> Konstantin
>
> ________________________________
> De: Confocal Microscopy List <
[hidden email]> en
> nombre de Craig Brideau <
[hidden email]>
> Enviado: lunes, 22 de marzo de 2021 20:00
> Para:
[hidden email]
> <
[hidden email]>
> Asunto: Re: Are lower magnification objectives brighter?
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
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> *****
>
> Thanks for the great answer James! For additional information, here's
> some power readings from one of our confocals at various wavelengths.
> As you can see between the 20x and 60x there is considerable
> variability by laser color as well as by magnification. Units are in microwatts.
> Intensity measured (in micro watt) using 20X (air) objective
> Percentage of laser used:
> Wavelength of the laser 25% 50% 75% 100%
> 408 78 233 400 555
> 457 4 7 10 11
> 476 10 19 27 35
> 488 67 133 195 246
> 514 27 53 78 98
> 561 195 380 555 700
> 638 no data no data no data no data
> Intensity measured (in micro watt) using 60X (oil) objective
> Percentage of laser used:
> Wavelength of the laser 25% 50% 75% 100%
> 408 14 28 63 77
> 457 0 0 2.3 3
> 476 3 6 8 10
> 488 18 35 51 66
> 514 9 17 26 32
> 561 73 141 203 261
> 638 no data no data no data no data
> 0 : value under detection level
> Craig
>
> On Mon, Mar 22, 2021 at 12:46 PM Jonkman, James <
>
[hidden email]> wrote:
>
> > *****
> > To join, leave or search the confocal microscopy listserv, go to:
> >
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> > Cm
> > model%40KENT.EDU%7Ca9523323a2384461a25508d8ed6d8bd0%7Ce5a06f4a1ec44d
> > 01
> > 8f73e7dd15f26134%7C1%7C0%7C637520402490338766%7CUnknown%7CTWFpbGZsb3
> > d8
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> > C3
> > 000&sdata=SDWAOFXB3UXBeN1uo%2FfFWOsi3QT2yJ8vUtUyhxXidc8%3D&r
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> in your posting.
> > *****
> >
> > Hi, Andreas. It bothered me for many years that people still
> > claimed that a CLSM gives you brighter images when you use a lower
> > magnification objective (for the same NA). Physically, it didn't
> > make sense to me. I have both a 63x/1.4NA and a 40x/1.4NA on the
> > same Zeiss
> LSM700 confocal.
> > If you consider the focused spot on a CLSM, the size of the PSF
> > depends only on the NA of the objective and not it's magnification,
> > so the illumination will be identical for a 40x and a 63x objective
> > with the same NA (assuming that you overfill the back aperture in
> > both cases to take full advantage of the NA of the lens). Now
> > consider the
> > detection: again, only the NA determines how much light you will
> > collect by the lens. So it wouldn't make any sense for a CLSM to
> > give you a "brighter" image with a lower mag lens when both lenses
> > have the
> same NA.
> >
> > But wait! When you look into the binocular it looks brighter with
> > the 40x lens. AND, if you keep all of the same settings (laser
> > power percentage and detector gain) you get a brighter image with
> > the 40x objective. So what's going on? My relatively new Thorlabs
> > power meter (PM400 console with S170C sensor) is compatible with oil
> > immersion and the difference in brightness with the 40x objective is
> > 100% accounted for by the change in laser power when you switch
> > between these objectives. The change in laser power is due to the
> > smaller back aperture of the 63x objective. In other words, when
> > you switch from the 40x to the 63x objective, the edges of the laser
> > beam are blocked by the smaller aperture of the 63x lens, so less
> > excitation reaches the sample. If you adjust the % laser power
> > slider so that both the 40x and 63x objectives are reading the same
> illumination intensity, then you get the exact same image with both lenses.
> >
> > As you mentioned, I tried to explain this in our Nat Prot paper in
> > Supplementary Figure 1 and I included some of the data there (free
> > download for the Supp Figs - for the full paper if anyone needs it
> > I'm happy to email it to them).
> >
>
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> 26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1J80nGEFK$
> [nam11[.]safelinks[.]protection[.]outlook[.]com].
> > nature.com%2Farticles%2Fs41596-020-0313-9&data=04%7C01%7Cmmodel%
> > 40
> > KENT.EDU%7Ca9523323a2384461a25508d8ed6d8bd0%7Ce5a06f4a1ec44d018f73e7
> > dd
> > 15f26134%7C1%7C0%7C637520402490338766%7CUnknown%7CTWFpbGZsb3d8eyJWIj
> > oi
> > MC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&am
> > p;
> > sdata=4Ys8AEy%2FxAfzJCXw%2FclIfrT8GuWUNF9AMZP%2FWZhsgNA%3D&reser
> > ve
> > d=0
> >
> > So why is this so broadly misunderstood (I have heard it many, many
> > times!)? When we read the classic textbooks on the brightness of a
> > microscope image, these were originally written with respect to
> > transmitted-light brightfield microscopy: it's not obvious that they
> > should apply to confocal microscopy or even to widefield
> > fluorescence
> microscopy.
> > On the Microscopy Primer website (
> >
>
https://urldefense.com/v3/__https://nam11.safelinks.protection.outlook> .com/?url=https*3A*2F*2Fwww__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0UBtnpA
> 26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1J80nGEFK$
> [nam11[.]safelinks[.]protection[.]outlook[.]com].
> > microscopyu.com%2Fmicroscopy-basics%2Fimage-brightness&data=04%7
> > C0
> > 1%7Cmmodel%40KENT.EDU%7Ca9523323a2384461a25508d8ed6d8bd0%7Ce5a06f4a1
> > ec
> > 44d018f73e7dd15f26134%7C1%7C0%7C637520402490338766%7CUnknown%7CTWFpb
> > GZ
> > sb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0
> > %3
> > D%7C3000&sdata=GCBCeYd7eSP4mi6lYcK3oYOMwiQxZ10b%2F0tVRpIThTA%3D&
> > am
> > p;reserved=0 ), for example, they start with the typical statement
> > that the Image Brightness is proportional to (NA/M)^2. They go on
> > to mention that for fluorescence the Image Brightness should be
> > lambda NA^4/ M^2. However, they fail to mention that the reason for
> > the Mag
> being in the denominator of the equation is because the size of the
> back aperature depends on Mag in this way. So even for a widefield
> fluorescence microscope, the increase in brightness is caused by
> increased illumination on the sample, not increased detection
> efficiency, which is not very helpful in this era of over-powered fluorescence lamps.
> >
> > If the confocal manufacturers would specify their laser powers in
> > real-world units instead of %_of_maximum, when you switch lenses you
> > would immediately see that that for a given excitation power density
> > (in W/cm^2) you get the same intensity image for 2 lenses with the
> > same NA, regardless of the mag of the lens.
> >
> > Cheers,
> > James
> >
> >
> > -----------------------------------------------
> > James Jonkman, Staff Scientist
> > Advanced Optical Microscopy Facility (AOMF)
> > and Wright Cell Imaging Facility (WCIF)
> > University Health Network
> > MaRS, PMCRT tower, 101 College St., Room 15-305
> > Toronto, ON, CANADA M5G 1L7
> >
[hidden email] Tel: 416-581-8593
> >
> >
https://urldefense.com/v3/__https://nam11.safelinks.protection.outlo> > ok
> > .com/?url=http*3A*2F*2Fwww.a__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0UBt
> > np A26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1J-PhdIG6$
> > [nam11[.]safelinks[.]protection[.]outlook[.]com]
> > omf.ca%2F&data=04%7C01%7Cmmodel%40KENT.EDU%7Ca9523323a2384461a25
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> > pqrLCFoREVxEIHTzs%3D&reserved=0<
https://urldefense.com/v3/__https:> > //nam11.safelinks.protection__;!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0UBtnpA2
> > 6V Qtygcy5Kds6dgWEHngml3WfaZWN7Rk1J3rm7zaj$
> > [nam11[.]safelinks[.]protection]
> > .outlook.com/?url=http%3A%2F%2Fwww.aomf.ca%2F&data=04%7C01%7Cmmo
> > de
> > l%40KENT.EDU%7Ca9523323a2384461a25508d8ed6d8bd0%7Ce5a06f4a1ec44d018f
> > 73
> > e7dd15f26134%7C1%7C0%7C637520402490348759%7CUnknown%7CTWFpbGZsb3d8ey
> > JW
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> > amp;sdata=FhVEsqwOD9EyXWBTZbMmVwSaXspqrLCFoREVxEIHTzs%3D&reserve
> > d=
> > 0>
> >
> >
> > -----Original Message-----
> > From: Confocal Microscopy List
> > [mailto:
[hidden email]]
> > On Behalf Of Michael Giacomelli
> > Sent: Monday, March 22, 2021 1:10 PM
> > To:
[hidden email]
> > Subject: [External] Re: [EXT] Are lower magnification objectives
> brighter?
> >
> > *****
> > To join, leave or search the confocal microscopy listserv, go to:
> >
> >
https://urldefense.com/v3/__https://nam11.safelinks.protection.outlo> > ok
> > .com/?url=https*3A*2F*2Furld__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0UBt
> > np A26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1JzkdyAOQ$
> > [nam11[.]safelinks[.]protection[.]outlook[.]com]
> > efense.com%2Fv3%2F__http%3A%2F%2Flists.umn.edu%2Fcgi-bin%2Fwa%3FA0%3
> > Dc
> > onfocalmicroscopy__%3B!!CjcC7IQ!cVq_1LwAtt5kR7u0kLVqLgj6Ibrhi5SENs87
> > a8
> > corilw8S_7MAMBm34ZykSs8SUfn_6GBWBm%24&data=04%7C01%7Cmmodel%40KE
> > NT
> > .EDU%7Ca9523323a2384461a25508d8ed6d8bd0%7Ce5a06f4a1ec44d018f73e7dd15
> > f2
> > 6134%7C1%7C0%7C637520402490348759%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC
> > 4w
> > LjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sd
> > at
> > a=YamE1qZW2OOPk462j1rGa1zJ2O9w8qfDEUdpY2zMbG8%3D&reserved=0
> > [lists[.]umn[.]edu] Post images on
> >
https://urldefense.com/v3/__https://nam11.safelinks.protection.outlo> > ok
> > .com/?url=https*3A*2F*2Furld__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0UBt
> > np A26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1JzkdyAOQ$
> > [nam11[.]safelinks[.]protection[.]outlook[.]com]
> > efense.com%2Fv3%2F__http%3A%2F%2Fwww.imgur.com__%3B!!CjcC7IQ!cVq_1Lw
> > At
> > t5kR7u0kLVqLgj6Ibrhi5SENs87a8corilw8S_7MAMBm34ZykSs8SUfn8HHnv60%24&a
> > mp
> > ;data=04%7C01%7Cmmodel%40KENT.EDU%7Ca9523323a2384461a25508d8ed6d8bd0
> > %7
> > Ce5a06f4a1ec44d018f73e7dd15f26134%7C1%7C0%7C637520402490348759%7CUnk
> > no
> > wn%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWw
> > iL
> > CJXVCI6Mn0%3D%7C3000&sdata=Xkk%2BxZYn%2Fp1oYe%2BcPSDxVVjjyaom5Gp
> > OF
> > SVLc6Bztp0%3D&reserved=0 [imgur[.]com] and include the link in
> > your posting.
> > *****
> >
> > Hi Andreas,
> >
> > If you divide the same amount of light across a more magnified PSF,
> > then the PSF covers more pixels and so each pixel gets fewer photons.
> > However, in this case you would also be more densely sampled, and
> > you could digitally downsample the image, which would have the
> > effect of putting the same number photons into fewer pixels. If
> > dark and read noise are low, this would effectively give you the
> > same image as you would have gotten using a lower magnification to begin with.
> >
> > Mike
> >
> > On Mon, Mar 22, 2021 at 1:02 PM Andreas Bruckbauer <
> >
[hidden email]> wrote:
> >
> > > *****
> > > To join, leave or search the confocal microscopy listserv, go to:
> > >
> > >
https://urldefense.com/v3/__https://nam11.safelinks.protection.out> > > lo
> > > ok.com/?url=https*3A*2F*2Fur__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0U
> > > Bt npA26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1J4p9Qajh$
> > > [nam11[.]safelinks[.]protection[.]outlook[.]com]
> > > ldefense.proofpoint.com%2Fv2%2Furl%3Fu%3Dhttp-3A__lists.umn.edu_cg
> > > i-
> > > &data=04%7C01%7Cmmodel%40KENT.EDU%7Ca9523323a2384461a25508d8ed
> > > 6d
> > > 8bd0%7Ce5a06f4a1ec44d018f73e7dd15f26134%7C1%7C0%7C6375204024903487
> > > 59
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> > > iI
> > > 6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=355%2FOydVsjZ%2Fyb05O7GUO
> > > gH
> > > xuKsM%2BiK4DjJYGU%2FxrUE%3D&reserved=0
> > > 2Dbin_wa-3FA0-3Dconfocalmicroscopy&d=DwIFaQ&c=kbmfwr1Yojg42sGEpaQh
> > > 5o
> > > fM
> > > HBeTl9EI2eaqQZhHbOU&r=0LyF_z8oU1XGGyisIeOIXyIGIM5IYb3NcLjxHjUca5Y&
> > > m=
> > > aB
> > > nPuVl44CvsNnSHKnYuIZtIZCpEktGwklB9D7Cdvqg&s=NSCBIiLfvnxwocRL4-vTUD
> > > Eo
> > > S-
> > > 65dOAWbgN2OxNnKaw&e=
> > > Post images on
> > >
https://urldefense.com/v3/__https://nam11.safelinks.protection.out> > > lo
> > > ok.com/?url=https*3A*2F*2Fur__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0U
> > > Bt npA26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1J4p9Qajh$
> > > [nam11[.]safelinks[.]protection[.]outlook[.]com]
> > > ldefense.proofpoint.com%2Fv2%2Furl%3Fu%3Dhttp-3A__www.imgur.com%26
> > > d%
> > > 3DDw&data=04%7C01%7Cmmodel%40KENT.EDU%7Ca9523323a2384461a25508
> > > d8
> > > ed6d8bd0%7Ce5a06f4a1ec44d018f73e7dd15f26134%7C1%7C0%7C637520402490
> > > 34
> > > 8759%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiL
> > > CJ
> > > BTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=gD6IgbED16AsVzP5GvSPq
> > > 0W
> > > sRALiXOnn1PZWkjxF9yY%3D&reserved=0
> > > IFaQ&c=kbmfwr1Yojg42sGEpaQh5ofMHBeTl9EI2eaqQZhHbOU&r=0LyF_z8oU1XGG
> > > yi
> > > sI
> > > eOIXyIGIM5IYb3NcLjxHjUca5Y&m=aBnPuVl44CvsNnSHKnYuIZtIZCpEktGwklB9D
> > > 7C dv qg&s=roevs0gDRqIs8bZKBI0bE8ejnEfLkz7n1a9vJZoNMeE&e=
> > > and include the link in your posting.
> > > *****
> > >
> > > Dear all,
> > > Are lower magnification objectives brighter than higher
> > > magnification ones when they have the same NA, e.g. a 40x NA 1.4
> > > objective compared to 63x NA 1.4? I mean for confocal microscopy.
> > >
> > > Confocal.nl stated this is a recent webinar and on their website:
> > > "A lower magnification allows for a larger field of view and
> > > brighter images, since light intensity is inversely proportional
> > > to the magnification squared"
> > >
https://urldefense.com/v3/__https://nam11.safelinks.protection.out> > > lo
> > > ok.com/?url=https*3A*2F*2Fur__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0U
> > > Bt npA26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1J4p9Qajh$
> > > [nam11[.]safelinks[.]protection[.]outlook[.]com]
> > > ldefense.proofpoint.com%2Fv2%2Furl%3Fu%3Dhttps-3A__www.confocal.nl
> > > _-
> > > &data=04%7C01%7Cmmodel%40KENT.EDU%7Ca9523323a2384461a25508d8ed
> > > 6d
> > > 8bd0%7Ce5a06f4a1ec44d018f73e7dd15f26134%7C1%7C0%7C6375204024903487
> > > 59
> > > %7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBT
> > > iI
> > > 6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=wCEaE8n4FidCGGpODX1yZnEIN
> > > %2
> > > FYIBPQJgvR7BXli%2FtU%3D&reserved=0
> > > 23rcm2&d=DwIFaQ&c=kbmfwr1Yojg42sGEpaQh5ofMHBeTl9EI2eaqQZhHbOU&r=0L
> > > yF
> > > _z
> > > 8oU1XGGyisIeOIXyIGIM5IYb3NcLjxHjUca5Y&m=aBnPuVl44CvsNnSHKnYuIZtIZC
> > > pE kt
> > > GwklB9D7Cdvqg&s=FRdNlG-gKHQ7Lkl2vBS1jL6SlXxTyAMcF_pCXgVvfao&e=
> > >
> > > I would think that this is caused by less light going through the
> > > smaller back focal aperture when the illumination is held constant?
> > > Most of the light is clipped as explained in fig 1 of
> > >
https://urldefense.com/v3/__https://nam11.safelinks.protection.out> > > lo
> > > ok.com/?url=https*3A*2F*2Fur__;JSUl!!CjcC7IQ!eEhOfVie8uBJ5Jgg4Ya0U
> > > Bt npA26VQtygcy5Kds6dgWEHngml3WfaZWN7Rk1J4p9Qajh$
> > > [nam11[.]safelinks[.]protection[.]outlook[.]com]
> > > ldefense.proofpoint.com%2Fv2%2Furl%3Fu%3Dhttps-3A__www.nature.com_
> > > ar
> > > &data=04%7C01%7Cmmodel%40KENT.EDU%7Ca9523323a2384461a25508d8ed
> > > 6d
> > > 8bd0%7Ce5a06f4a1ec44d018f73e7dd15f26134%7C1%7C0%7C6375204024903487
> > > 59
> > > %7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBT
> > > iI
> > > 6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=3eCTBSNU%2BlS9rvBZUNH66SA
> > > s%
> > > 2BDLVPItkhqzFMgOpGTM%3D&reserved=0
> > > ticles_s41596-2D020-2D0313-2D9&d=DwIFaQ&c=kbmfwr1Yojg42sGEpaQh5ofM
> > > HB
> > > eT
> > > l9EI2eaqQZhHbOU&r=0LyF_z8oU1XGGyisIeOIXyIGIM5IYb3NcLjxHjUca5Y&m=aB
> > > nP
> > > uV
> > > l44CvsNnSHKnYuIZtIZCpEktGwklB9D7Cdvqg&s=WuqudKbziHqalUr5fiK7sSsr_C
> > > yQ
> > > 63 nsf-C6L2XiGYA&e= So, the microscope manufacturer could adjust
> > > the illumination beam path and laser powers to best suit the
> > > objective?Or are lower magnification objectives really brighter?
> > >
> > > The field of view will obviously be larger for the 40x objective,
> > > but I am more interested to understand the claimed benefit in
> brightness.
> > >
> > > best wishes
> > >
> > > Andreas
> > >
> >
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