LED Lighting and optical resolution questions

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75RR
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Re: LED Lighting and optical resolution questions

#31 Post by 75RR » Fri Nov 13, 2020 11:59 am

LouiseScot wrote:
Thu Nov 12, 2020 11:08 pm
Really, I'd need a something which does demonstrate closer spacing to prove it, but not sure what.
Link to an interesting article called: Diatom Pleurosigma angulatum - a versatile 'demonstration' subject.

The footnotes are also interesting.

http://www.microscopy-uk.org.uk/mag/ind ... -test.html

Kemp 8 Test Slide with added info (Note that size and µm/Stria period lies within a range for these diatoms so YMMV but will be within acceptable tolerances)
.
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Re: LED Lighting and optical resolution questions

#32 Post by LouiseScot » Fri Nov 13, 2020 3:58 pm

Hobbyst46 wrote:
Fri Nov 13, 2020 8:49 am
LouiseScot wrote:
Thu Nov 12, 2020 11:08 pm
...My calculations came up with a value of 910-918nm which compares with an example published image of ~880nm. I calculated the theoretical resolution of a 40x/0.65 objective to be 423nm @ wavelength of 550nm. I imagine I could probably distinguish dots that are around twice as closely spaced... Really, I'd need a something which does demonstrate closer spacing to prove it, but not sure what...
Maybe a diatom of more closely spaced dots. However, the 423nm is based on the Abbe formula, which assumes that the NA of the condenser is the same as that of the objective. The Raleigh formula would give a distance of: 550/{0.65+NA_condenser}.
Hiya
I wasn't sure about including the NA of the condenser (1.25) since my images were taken with the iris closed down somewhat. In any case, I need something with smaller markings... Also, I've been doing my measurements on printed versions. I did a comparison with on-screen images and the on-screen version gives me a pore spacing of about 10% smaller.
Thanks
Louise
ps annoyingly I'm not getting email notifications of the posts anymore. This has happened before but I don't really know what causes it...
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#33 Post by LouiseScot » Fri Nov 13, 2020 4:13 pm

75RR wrote:
Fri Nov 13, 2020 7:11 am
.
Interesting comparison

Took the liberty of placing the images side by side and reducing the rail photo to the same size as that of the Swift

I would say the Swift has the edge here
.
I think it's a little difficult to say one is 'better' than the other since different cameras are being used, different lighting, and different post processing adjustments. They are very similar, though. You'd think an Olympus Plan N would outperform a cheap achromat but perhaps in reality there isn't much in it. I've done another comparison with the Nikon 20x Apo on the Rail. I'd expect that to, in principle, give superior resolution since it has a NA of 0.75. But, again, I find it hard to tell after resizing the Nikon image by 200%:
Nikon20x_Pleurosigma_3_200pcCropScale.jpg
Nikon20x_Pleurosigma_3_200pcCropScale.jpg (66.17 KiB) Viewed 9664 times
Doing the measurement on-screen rather than on a printout gives a pore spacing of 775nm rather than 864nm i.e. about 10% smaller. (I've only been using a ruler to do the measurements so not great precision).

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#34 Post by LouiseScot » Fri Nov 13, 2020 4:23 pm

75RR wrote:
Fri Nov 13, 2020 11:59 am
LouiseScot wrote:
Thu Nov 12, 2020 11:08 pm
Really, I'd need a something which does demonstrate closer spacing to prove it, but not sure what.
Link to an interesting article called: Diatom Pleurosigma angulatum - a versatile 'demonstration' subject.

The footnotes are also interesting.

http://www.microscopy-uk.org.uk/mag/ind ... -test.html

Kemp 8 Test Slide with added info (Note that size and µm/Stria period lies within a range for these diatoms so YMMV but will be within acceptable tolerances)
.
Hiya

The Gyrosigma gives a pore-spacing value comparable to my latest measurement of 775nm for the similar Pleurosigma formosa. It looks like the striae details can be used to distinguish them https://www.tandfonline.com/doi/abs/10. ... 91.9705182
I'd like to get hold of some of species with the finer details... It's annoying that you can buy refined/milled diatomaceous/diatomite but getting hold of the raw material isn't so easy. Oh well.

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#35 Post by 75RR » Fri Nov 13, 2020 4:32 pm

LouiseScot wrote:
Fri Nov 13, 2020 4:23 pm
I'd like to get hold of some of species with the finer details... I
https://www.ebay.co.uk/itm/Watson-Antiq ... SwsgtfoVmf
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Re: LED Lighting and optical resolution questions

#36 Post by LouiseScot » Fri Nov 13, 2020 4:35 pm

75RR wrote:
Fri Nov 13, 2020 11:59 am
LouiseScot wrote:
Thu Nov 12, 2020 11:08 pm
Really, I'd need a something which does demonstrate closer spacing to prove it, but not sure what.
Link to an interesting article called: Diatom Pleurosigma angulatum - a versatile 'demonstration' subject.

The footnotes are also interesting.

http://www.microscopy-uk.org.uk/mag/ind ... -test.html

Kemp 8 Test Slide with added info (Note that size and µm/Stria period lies within a range for these diatoms so YMMV but will be within acceptable tolerances)
.
Useful article - thanks!
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#37 Post by LouiseScot » Fri Nov 13, 2020 5:08 pm

75RR wrote:
Fri Nov 13, 2020 4:32 pm
LouiseScot wrote:
Fri Nov 13, 2020 4:23 pm
I'd like to get hold of some of species with the finer details... I
https://www.ebay.co.uk/itm/Watson-Antiq ... SwsgtfoVmf
Thanks for that - I have put in a bid. However, a similar auction the other day went up to around £124, which I think is too much!

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#38 Post by SWmicro » Fri Nov 13, 2020 5:15 pm

Very interesting, thanks for showing, I have been contemplating a new 'scope for some time, possibly either the Swift 350T or the 380T.

I have taken the liberty of playing with your image and doing some measuring in Gimp :-
First I selected and copied your cal. arrow heads, moved them over and rotated, found just a tiny bit over 11 pore intervals, say 11.3, which for 10,000nm gives 885nm separation.

Then, (just in case the rotation isn't proportional in x and y) I made a brush centre on your top arrow and tangent to the bottom one and moved the green measure over, same result !

And, for good measure, copied the circle layer twice and find much the same at top and bottom :)
L1.jpg
L1.jpg (51.51 KiB) Viewed 9649 times
L2.jpg
L2.jpg (54.27 KiB) Viewed 9649 times
L3.jpg
L3.jpg (55.91 KiB) Viewed 9649 times

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Re: LED Lighting and optical resolution questions

#39 Post by LouiseScot » Fri Nov 13, 2020 6:04 pm

SWmicro wrote:
Fri Nov 13, 2020 5:15 pm
Very interesting, thanks for showing, I have been contemplating a new 'scope for some time, possibly either the Swift 350T or the 380T.

I have taken the liberty of playing with your image and doing some measuring in Gimp :-
First I selected and copied your cal. arrow heads, moved them over and rotated, found just a tiny bit over 11 pore intervals, say 11.3, which for 10,000nm gives 885nm separation.

Then, (just in case the rotation isn't proportional in x and y) I made a brush centre on your top arrow and tangent to the bottom one and moved the green measure over, same result !

And, for good measure, copied the circle layer twice and find much the same at top and bottom :)

L1.jpg
L2.jpg
L3.jpg
Hi

I've been very impressed by the Swift 380T - excellent value for money (only £215.99 from Amazon UK) and the optics are very good, in my opinion :) I should probably mention that I've probably lost some fine details by using jpegs but the images have been good enough for my needs.

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#40 Post by hans » Fri Nov 13, 2020 7:17 pm

LouiseScot wrote:
Fri Nov 13, 2020 4:13 pm
I think it's a little difficult to say one is 'better' than the other since different cameras are being used, different lighting, and different post processing adjustments. They are very similar, though. You'd think an Olympus Plan N would outperform a cheap achromat but perhaps in reality there isn't much in it. I've done another comparison with the Nikon 20x Apo on the Rail. I'd expect that to, in principle, give superior resolution since it has a NA of 0.75. But, again, I find it hard to tell after resizing the Nikon image by 200%:
It looks like the spherical aberration (most obvious symptom being poor contrast) that viktor pointed out in the previous thread is still showing in these examples. How did you decide what distance to place the tube lens from the camera sensor? If you did it based on magnification (trying to get a particular size/crop of the image circle) you may want to at least temporarily try instead focusing the tube lens and camera at infinity such that you can get sharp photos of distant objects with the objective removed. Focusing the tube lens/camera combination at infinity will ensure your infinity-corrected objectives are being used at the correct working distance from the specimen.

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Re: LED Lighting and optical resolution questions

#41 Post by LouiseScot » Fri Nov 13, 2020 8:47 pm

hans wrote:
Fri Nov 13, 2020 7:17 pm
LouiseScot wrote:
Fri Nov 13, 2020 4:13 pm
I think it's a little difficult to say one is 'better' than the other since different cameras are being used, different lighting, and different post processing adjustments. They are very similar, though. You'd think an Olympus Plan N would outperform a cheap achromat but perhaps in reality there isn't much in it. I've done another comparison with the Nikon 20x Apo on the Rail. I'd expect that to, in principle, give superior resolution since it has a NA of 0.75. But, again, I find it hard to tell after resizing the Nikon image by 200%:
It looks like the spherical aberration (most obvious symptom being poor contrast) that viktor pointed out in the previous thread is still showing in these examples. How did you decide what distance to place the tube lens from the camera sensor? If you did it based on magnification (trying to get a particular size/crop of the image circle) you may want to at least temporarily try instead focusing the tube lens and camera at infinity such that you can get sharp photos of distant objects with the objective removed. Focusing the tube lens/camera combination at infinity will ensure your infinity-corrected objectives are being used at the correct working distance from the specimen.
Yes, it's focussed at infinity. The DCR-150 is in reverse mode. Maybe I should try it in 'normal' mode? I might try it with a less bright led source.

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#42 Post by 75RR » Fri Nov 13, 2020 9:12 pm

Did your bid win?
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Re: LED Lighting and optical resolution questions

#43 Post by LouiseScot » Fri Nov 13, 2020 9:24 pm

75RR wrote:
Fri Nov 13, 2020 9:12 pm
Did your bid win?
No it went for £27.01- I didn't think it was worth more than £15...

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#44 Post by hans » Sat Nov 14, 2020 2:46 am

LouiseScot wrote:
Fri Nov 13, 2020 8:47 pm
Yes, it's focussed at infinity. The DCR-150 is in reverse mode. Maybe I should try it in 'normal' mode?
Not easy to do a direct comparison, of course, but how do photos through the tube lens with objective removed look compared to ones through the objective?

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Re: LED Lighting and optical resolution questions

#45 Post by LouiseScot » Sat Nov 14, 2020 11:42 pm

hans wrote:
Sat Nov 14, 2020 2:46 am
LouiseScot wrote:
Fri Nov 13, 2020 8:47 pm
Yes, it's focussed at infinity. The DCR-150 is in reverse mode. Maybe I should try it in 'normal' mode?
Not easy to do a direct comparison, of course, but how do photos through the tube lens with objective removed look compared to ones through the objective?
Hard to compare, really. I double checked the view through the dcr-150 on a distant building earlier(hopefully close enough to infinity). This is with the camera attached and selected part of the image magnified 200%. So it's like having a prime telephoto lens attached. The tube setup includes a helical focuser so it's easy to make fine adjustments. I haven't tried reversing the dcr-150 yet. Will do some more tomorrow.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#46 Post by 75RR » Sun Nov 15, 2020 6:09 am

LouiseScot wrote:
Sat Nov 14, 2020 11:42 pm
Hard to compare, really. I double checked the view through the dcr-150 on a distant building earlier(hopefully close enough to infinity).
I use the Moon (when I can find it) to focus lens on infinity, I then use masking tape to keep it in place.
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Re: LED Lighting and optical resolution questions

#47 Post by LouiseScot » Sun Nov 15, 2020 10:01 am

75RR wrote:
Sun Nov 15, 2020 6:09 am
LouiseScot wrote:
Sat Nov 14, 2020 11:42 pm
Hard to compare, really. I double checked the view through the dcr-150 on a distant building earlier(hopefully close enough to infinity).
I use the Moon (when I can find it) to focus lens on infinity, I then use masking tape to keep it in place.
It's permacloud here at the moment :( The helical focuser has a locking screw :)
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#48 Post by mrsonchus » Sun Nov 15, 2020 10:33 am

LouiseScot wrote:
Sun Nov 15, 2020 10:01 am
..........

It's permacloud here at the moment :( The helical focuser has a locking screw :)
Louise
Ditto Cumbria Louise! :(

Interesting thread and to me the 380T looks to be a very nice 'scope indeed for the price - very nice images with plenty of detail. Looks like a real bargain for a new 'scope - a really reasonable price to pay for the out-of-the-box performance and confidence that a new 'scope can give. Thanks for an interesting post, not my area with diatoms really, but some interesting discussion and good images.
John B

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Re: LED Lighting and optical resolution questions

#49 Post by LouiseScot » Sun Nov 15, 2020 1:51 pm

mrsonchus wrote:
Sun Nov 15, 2020 10:33 am
LouiseScot wrote:
Sun Nov 15, 2020 10:01 am
..........

It's permacloud here at the moment :( The helical focuser has a locking screw :)
Louise
Ditto Cumbria Louise! :(

Interesting thread and to me the 380T looks to be a very nice 'scope indeed for the price - very nice images with plenty of detail. Looks like a real bargain for a new 'scope - a really reasonable price to pay for the out-of-the-box performance and confidence that a new 'scope can give. Thanks for an interesting post, not my area with diatoms really, but some interesting discussion and good images.
Thanks. Yeah, the Swift isn't bad for a basic finite scope :)
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#50 Post by LouiseScot » Sun Nov 15, 2020 2:07 pm

I turned the dcr-150 around and refocused on a distant building. Here are a few Pleurosigma images I took with the Nikon 20x:

Crop at 100% size:
Pleurosigma20x_100pc_crop_dcr150rev.jpg
Pleurosigma20x_100pc_crop_dcr150rev.jpg (57.44 KiB) Viewed 9222 times

Crop at 200% size:
Pleurosigma20x_200pc_crop2_dcr150rev.jpg
Pleurosigma20x_200pc_crop2_dcr150rev.jpg (56.7 KiB) Viewed 9222 times

Crop at 100% in reflected light:
Pleurosigma20x_Refl_100pc_crop2_dcr150rev.jpg
Pleurosigma20x_Refl_100pc_crop2_dcr150rev.jpg (66.09 KiB) Viewed 9222 times
I think it's pretty much the same? I'm afraid I'm not a very good judge of these things. I thing it's quite a difficult subject since the contrast is low. I've adjusted contrast and brightness somewhat. Also, Nikon 20x/0.75 is difficult to focus because it has a miniscule depth of focus. The reflected light image is interesting because of the enhanced 3D modelling effect but it's hard to also get the pore detail at 20x.
Any thoughts? Someone mentioned previously I had a lot of spherical aberration but I'm not really sure how to tell?
Thanks
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#51 Post by SWmicro » Sun Nov 15, 2020 8:27 pm

LouiseScot wrote:
Thu Nov 12, 2020 11:08 pm
Anyway, here are a couple of sample images from the Rail microscope/Olympus 40x (Canon 550d) and the Swift (Canon 1100d - slightly bigger pixels). They were set to 100% image size and cropped. I think there are probably some diffraction effects taking place:
Swift 40x:
Swift_Pleurosigma1_+scale.jpg
I am very impressed with your results and agree that the Swift scopes are being offered at very reasonable cost (any less and they will be paying us to use them ! )

I have just been reading your post in the "My Equipment" area and am unsure if you have removed the 'mystery' tube lens for this pic. ?
I have not seen any ref to tube lens in Swift literature ! Only to a 1x C-mount adapter which I assumed would thus be just a 'straight through' port. I wonder if they have introduced a new model.

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Re: LED Lighting and optical resolution questions

#52 Post by LouiseScot » Sun Nov 15, 2020 9:06 pm

SWmicro wrote:
Sun Nov 15, 2020 8:27 pm
LouiseScot wrote:
Thu Nov 12, 2020 11:08 pm
Anyway, here are a couple of sample images from the Rail microscope/Olympus 40x (Canon 550d) and the Swift (Canon 1100d - slightly bigger pixels). They were set to 100% image size and cropped. I think there are probably some diffraction effects taking place:
Swift 40x:
Swift_Pleurosigma1_+scale.jpg
I am very impressed with your results and agree that the Swift scopes are being offered at very reasonable cost (any less and they will be paying us to use them ! )

I have just been reading your post in the "My Equipment" area and am unsure if you have removed the 'mystery' tube lens for this pic. ?
I have not seen any ref to tube lens in Swift literature ! Only to a 1x C-mount adapter which I assumed would thus be just a 'straight through' port. I wonder if they have introduced a new model.
Ah, sorry for any confusion - some of the pics are taken with the Swift 380T finite system + Canon 1100d. But most of the pics were taken using my part DIY focus rail system which uses infinity corrected lenses and a tube lens consisting of a Raynox DCR-150 (normally used to convert a standard lens to macro), plus a Canon550d. The Swift pics were just taken in order to do a comparison.
Hope that's clear :)
I'm trying to get the best images I can with the focus rail system but there are a number of variables...
Thanks
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#53 Post by hans » Sun Nov 15, 2020 9:28 pm

LouiseScot wrote:
Sun Nov 15, 2020 2:07 pm
I'm afraid I'm not a very good judge of these things. I thing it's quite a difficult subject since the contrast is low. I've adjusted contrast and brightness somewhat. Also, Nikon 20x/0.75 is difficult to focus because it has a miniscule depth of focus. ... Someone mentioned previously I had a lot of spherical aberration but I'm not really sure how to tell?
Yeah I think it is hard to judge just looking at overall appearance of photos. Spherical aberration can explain a general hazy look and lack of contrast ("soft focus" in photography) but so can a lot of other things. Photographs of scenes with small, bright specular highlights can clearly demonstrate the effect on points shown in https://en.wikipedia.org/wiki/File:Sphe ... n-disk.jpg but not so common to see small, bright highlights in bright field transmitted-light images.

The relatively poor contrast of the Olympus 40x compared to the swift was maybe suspicious, but with the other variables (different camera) hard to say.

May be easier, rather than trying to diagnose from the look of the photos, to experiment with some other common causes of problems. With positioning of tube lens ruled out, might be good to look into cover glass thickness next? I think you mentioned elsewhere this was an antique diatom slide? Have you tried to establish how close the depth of the diatoms below the cover glass surface is to 0.17 mm? May not explain the 40x Olympus/Swift difference, unless the Olympus is higher NA, but critical for your 20x 0.75. Have you seen figure 3 here:
https://www.microscopyu.com/microscopy- ... correction

If your motorized focus rail is calibrated (can be moved known, relative distances) you can measure the depth of the diatom by seeing how far you need to move it to go from focusing on defects/dirt on the surface to focusing on the diatom, then correct for plane-parallel plate effect of the cover glass and mountant on the focal distance. (At least, I think that works. I experimented measuring cover glass thickness that way on my Reichert Microstar IV and got reasonable results comparing against a micrometer.) If you try this, best to move the focus carefully in one direction only through both focus points to avoid inaccuracy due to backlash.
Last edited by hans on Sun Nov 15, 2020 10:24 pm, edited 1 time in total.

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Re: LED Lighting and optical resolution questions

#54 Post by SWmicro » Sun Nov 15, 2020 9:56 pm

LouiseScot wrote:
Sun Nov 15, 2020 9:06 pm
SWmicro wrote:
Sun Nov 15, 2020 8:27 pm
LouiseScot wrote:
Thu Nov 12, 2020 11:08 pm
and the Swift (Canon 1100d
Swift 40x:
Swift_Pleurosigma1_+scale.jpg
I am very impressed , , ,
Ah, sorry for any confusion -
And my apologies for fumbling the quote and causing more confusion (I have edited it a bit now for this post) !
I meant the pic of Pleurosigma using the Swift & Canon combo. Am I right to guess that you removed the tube lens and just used the Swift objective, projecting in its mount up its trinocular port,**, into the lensless Canon ? (ie. no other optics) ?

** Oh ho ! ah !,,, just before I hit the post button,,, I think I see where I am confused,,, You dismounted the Swift 40x objective from off the Swift scope body and put it on to your rail system ? ??

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Re: LED Lighting and optical resolution questions

#55 Post by LouiseScot » Sun Nov 15, 2020 10:37 pm

SWmicro wrote:
Sun Nov 15, 2020 9:56 pm
LouiseScot wrote:
Sun Nov 15, 2020 9:06 pm
SWmicro wrote:
Sun Nov 15, 2020 8:27 pm


I am very impressed , , ,
Ah, sorry for any confusion -
And my apologies for fumbling the quote and causing more confusion (I have edited it a bit now for this post) !
I meant the pic of Pleurosigma using the Swift & Canon combo. Am I right to guess that you removed the tube lens and just used the Swift objective, projecting in its mount up its trinocular port,**, into the lensless Canon ? (ie. no other optics) ?

** Oh ho ! ah !,,, just before I hit the post button,,, I think I see where I am confused,,, You dismounted the Swift 40x objective from off the Swift scope body and put it on to your rail system ? ??
No - I've just used the Swift trinocular port with a Canon 1100d fitted to it - no tube lens or anything - just camera+scope+Swift finite objective. It's only the rail system which uses a tube lens for the infinity objectives - camera + tube + tube lens + infinity objective.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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Re: LED Lighting and optical resolution questions

#56 Post by SWmicro » Sun Nov 15, 2020 11:02 pm

LouiseScot wrote:
Sun Nov 15, 2020 10:37 pm

No - I've just used the Swift trinocular port with a Canon 1100d fitted to it - no tube lens or anything
Ok, good, I understand, yes that is what I thought first off.

My interest was in what you said in your "My Microscope" section- " New arrival! " post :
"The trinocular part of the scope has a lens in it. Not much I can do about that, and I'm not sure how the lens affects the image? Anyone else It's better without using the narrow microscope adapter but is still apparent."
So, you have managed to remove it then, and thus if I buy the 380 (instead of the 350 ) I will be able to use my Canon on it also :) and get some good results with my rainwater little chums :) :)

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: LED Lighting and optical resolution questions

#57 Post by LouiseScot » Sun Nov 15, 2020 11:22 pm

SWmicro wrote:
Sun Nov 15, 2020 11:02 pm
LouiseScot wrote:
Sun Nov 15, 2020 10:37 pm

No - I've just used the Swift trinocular port with a Canon 1100d fitted to it - no tube lens or anything
Ok, good, I understand, yes that is what I thought first off.

My interest was in what you said in your "My Microscope" section- " New arrival! " post :
"The trinocular part of the scope has a lens in it. Not much I can do about that, and I'm not sure how the lens affects the image? Anyone else It's better without using the narrow microscope adapter but is still apparent."
So, you have managed to remove it then, and thus if I buy the 380 (instead of the 350 ) I will be able to use my Canon on it also :) and get some good results with my rainwater little chums :) :)
Ahh right - sorry. Yes it has what I think is a projection lens as opposed to a tube lens. It results in some vignetting with an APS-C dslr, though would be fine with a dedicated cmos microscope camera (I guess that's what's intended to be used). I haven't looked into trying to remove the lens - when I get a minute I'll have a look again.

Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: LED Lighting and optical resolution questions

#58 Post by LouiseScot » Sun Nov 15, 2020 11:29 pm

LouiseScot wrote:
Sun Nov 15, 2020 11:22 pm
SWmicro wrote:
Sun Nov 15, 2020 11:02 pm
LouiseScot wrote:
Sun Nov 15, 2020 10:37 pm

No - I've just used the Swift trinocular port with a Canon 1100d fitted to it - no tube lens or anything
Ok, good, I understand, yes that is what I thought first off.

My interest was in what you said in your "My Microscope" section- " New arrival! " post :
"The trinocular part of the scope has a lens in it. Not much I can do about that, and I'm not sure how the lens affects the image? Anyone else It's better without using the narrow microscope adapter but is still apparent."
So, you have managed to remove it then, and thus if I buy the 380 (instead of the 350 ) I will be able to use my Canon on it also :) and get some good results with my rainwater little chums :) :)
Ahh right - sorry. Yes it has what I think is a projection lens as opposed to a tube lens. It results in some vignetting with an APS-C dslr, though would be fine with a dedicated cmos microscope camera (I guess that's what's intended to be used). I haven't looked into trying to remove the lens - when I get a minute I'll have a look again.

Louise
ps
This is what it looks like with a Canon 1100d:
IMG_000429pc.jpg
IMG_000429pc.jpg (40.89 KiB) Viewed 9118 times
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

SWmicro
Posts: 134
Joined: Sat Nov 07, 2020 10:52 pm
Location: England.

Re: LED Lighting and optical resolution questions

#59 Post by SWmicro » Sun Nov 15, 2020 11:54 pm

LouiseScot wrote:
Sun Nov 15, 2020 11:29 pm
ps
This is what it looks like with a Canon 1100d:
IMG_000429pc.jpg
Thanks,,,,,,

Oh gosh, I think I am confused again ! :)
"no tube lens or anything"

"Yes it has what I think is a projection lens"

"results in some vignetting with an APS-C dslr"
But no worry, thanks for showing the whole frame, (mine is also an APS-C) I could live with that, at least you are seeing nearly the whole circle, not missing much.

Sorry for messing up your topic, having resolved that I'll let you/us get back to resolutions !

LouiseScot
Posts: 1167
Joined: Tue Jul 07, 2020 1:51 pm
Location: Scotland

Re: LED Lighting and optical resolution questions

#60 Post by LouiseScot » Mon Nov 16, 2020 12:07 am

SWmicro wrote:
Sun Nov 15, 2020 11:54 pm
LouiseScot wrote:
Sun Nov 15, 2020 11:29 pm
ps
This is what it looks like with a Canon 1100d:
IMG_000429pc.jpg
Thanks,,,,,,

Oh gosh, I think I am confused again ! :)
"no tube lens or anything"

"Yes it has what I think is a projection lens"

"results in some vignetting with an APS-C dslr"
But no worry, thanks for showing the whole frame, (mine is also an APS-C) I could live with that, at least you are seeing nearly the whole circle, not missing much.

Sorry for messing up your topic, having resolved that I'll let you/us get back to resolutions !
Um, my bad. It was my mistake to say "or anything"... I should have said "no tube lens but there is a projection lens"
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo

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