Need help choosing objectives

Everything relating to microscopy hardware: Objectives, eyepieces, lamps and more.
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Sansub2
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Need help choosing objectives

#1 Post by Sansub2 » Fri Oct 22, 2021 2:43 am

Gurus,

I am relatively new to amateur microscopy. Had a microscope for few years taking dust and recently rediscovered the hobby. I have AMScope trinacular microscope (160mm with 4, 10 and 40 acromat objectives) and a fisher scientific phase contrast microscope with 4,10, 40 and 100 place phase objectives. I am thinking of upgrading the Amscope objectives as the next step in my hobby. I have read many threads in this form and othe online sites. Member of microscope form and read every posts. The more I read the I see that there are too many choices and I am not sure how to choose my objectives. I am planning to take pictures and videos.

In ebay ,

1. There are fl, neofluar objectives for less than 150 can$.
2. There are plan versions of the above.
3. Wide verity of apochromat objective in various price range (Lomo seems to be cheap, leica, leitz, zeiss, olympus). The older version are around 250 cad$.
4. Plan versions of the above
5. Correction collars.

If I have about 500$ to spend, can you please suggest the best value for the money option? Appreciate any help and pointers.

BramHuntingNematodes
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Re: Need help choosing objectives

#2 Post by BramHuntingNematodes » Fri Oct 22, 2021 3:33 am

Oh goodness that is a kind of complicated question with 160 objectives your eyepieces have to match your objectives and parfocality is important. What do you want to look at
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Sansub2
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Re: Need help choosing objectives

#3 Post by Sansub2 » Fri Oct 22, 2021 3:37 am

Thanks for the quick response :). I am primarily looking at pond life's.

PeteM
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Re: Need help choosing objectives

#4 Post by PeteM » Fri Oct 22, 2021 5:09 am

Your Fisher phase contrast microscope, especially if it is one of their Japanese-made "Micromaster" models, should be pretty good for viewing pond critters. Is it in good condition?

One of the things about live protists is that they don't stay put; moving both up and down under a cover slip and back and forth. All of which limits the utility of more expensive plan achromat, fluorite, and apochromat objectives. The subjects just won't pose in a plan array.

The one thing I'd suggest adding is a 20x objective. You might also have some fun working with darkfield, oblique, and other contrast methods.

Sansub2
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Re: Need help choosing objectives

#5 Post by Sansub2 » Fri Oct 22, 2021 4:53 pm

Thanks for the response Pete. Sorry, forgot to mention earlier that I do have a generic 20 plan acro objective. I compared the image quality of the phase objectives to the acromat plain from Amscope. The normal acromat image and videos are more crisp. The different is noticeable. Please see the comparison video below. Will try to upload the objectives image shortly(the file size is large)

10 normal acromat


10 phase acromat


20 normal acromat


20 phase acromat
Last edited by Sansub2 on Fri Oct 22, 2021 5:03 pm, edited 1 time in total.

BramHuntingNematodes
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Re: Need help choosing objectives

#6 Post by BramHuntingNematodes » Fri Oct 22, 2021 4:59 pm

Are you confident you are employing the phase modality correctly?
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Sansub2
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Re: Need help choosing objectives

#7 Post by Sansub2 » Fri Oct 22, 2021 5:04 pm

BramHuntingNematodes wrote:
Fri Oct 22, 2021 4:59 pm
Are you confident you are employing the phase modality correctly?
Sorry, I was just showing the difference of using the phase objective in normal model. Not sure whether I misunderstood Pete's post.

BramHuntingNematodes
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Re: Need help choosing objectives

#8 Post by BramHuntingNematodes » Fri Oct 22, 2021 5:12 pm

Yeah there should be some resolution loss when using phase objectives in brightfield. They are at their best when in phase mode. If you haven't explored that avenue much it might be worth practicing with. There is a pretty deep field in these shots, so introducing higher NA objectives may create some problems there. Lomo had some lower NA better color-corrected objectives.

I think you might be able to squeeze a little more performance out of those achromats. On the other hand, with $500 you could proabbly buy a 410 and one of those genome sequencer apos if you want some superior lens performance.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Sansub2
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Re: Need help choosing objectives

#9 Post by Sansub2 » Fri Oct 22, 2021 5:41 pm

Here is a sample of phase video I was able to do. Playing with it for few months now. I don't have any prior scope to compare. Not sure whether it is good or need more tweaking. It seems to be centered when I look through the scope.


Sansub2
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Re: Need help choosing objectives

#10 Post by Sansub2 » Fri Oct 22, 2021 5:43 pm

.. and it doesnt seem to be good for dark field and oblique images.

BramHuntingNematodes
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Re: Need help choosing objectives

#11 Post by BramHuntingNematodes » Fri Oct 22, 2021 6:13 pm

Yeah I would only use a phase lens for phase and seems to be doing pretty good although phase sometimes has a little trouble with thick objects. Getting the ring to match the annulus as close as you can will minimize the halos even if this entails racking the condenser slightly out of kohler but you know you been playing with it.

If you like darkfield, and hey who doesn't, there are also some difficulties in getting high NA lenses as depending on the condenser or field stop you need to tamp down the NA anyway. You can get a cardioid condenser, the older Zeiss ones sometimes appear on the cheap, but that's going to be some of the most finicky work you ever done.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

BramHuntingNematodes
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Re: Need help choosing objectives

#12 Post by BramHuntingNematodes » Fri Oct 22, 2021 6:19 pm

OH, and I don't know if you ever played around with monochrome lighting but it improves phase on two fronts and also obviates the need for any superior color correction to the achromat.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Sansub2
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Re: Need help choosing objectives

#13 Post by Sansub2 » Fri Oct 22, 2021 6:36 pm

Thank you so much for all the responses Bram. Really appreciate it.

I am kicking myself for selling the zeiss monocular microscope that I had now. Will keep on eye on Facebook.

Can you please let me know where I can get more information about the monochrome lighting?

PeteM
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Re: Need help choosing objectives

#14 Post by PeteM » Fri Oct 22, 2021 6:45 pm

You might also want to check that your objectives, particularly the much older Fisher-branded ones, are scrupulously clean? Take them off the turret and use a magnifier or an inverted eyepiece and grazing light to check the surface. If it's not perfectly clean, read up on methods to remove any oil etc. that might be there.

Moving from achromats to plan achromats provides a clearly visible improvement for still subjects and photography. Not sure it's worth the cost compared to other ways to get cool images for protists (darkfield, oblique, polarization, Rheinberg, pseudo-DIC, better camera, brighter lighting for video, etc.)

Your videos look to have some sort of (darkfield stop?, digitally reversed?) dark background. Curious what that is.

I'd suggest getting a phase telescope (aka centering scope) to make sure your phase annuli are perfectly aligned. Shouldn't be much more than $50 for a good used one or a usable new one.

You probably know this, but you can get a bit more depth of field - after centering the condenser and putting the field iris (if present in your AmScope) just outside the field of view -- by stopping down the condenser iris a bit. If that ups the image quality, but you find yourself wanting more light -- a LED conversion might help.

BramHuntingNematodes
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Re: Need help choosing objectives

#15 Post by BramHuntingNematodes » Fri Oct 22, 2021 7:14 pm

Image

So the idea with the color correctin is to make the perfect focal length for all the visible wavelengths as close as possible, on this graph leading to flatness of the function. The apo and super-apo are definitely more flat over a wide range than the achro. On the other hand, if we pick the spectrum that encapsulates just where the achromat reaches a minimum, we get a very flat (albeit very short) segment. Bausch and Lomb advertises that their achromats correct for two colors, red and blue. THis doesn't mean it handles other colors badly, just that red and blue can be brought into focus at the exact same distance. These points correspond with where the red line intersects the black axis. The minimum of this function is then between those frequencies, and is about where the Wratten B no. 58 that B&L included with their phase set centers on, a nice emerald green. This is also around the frequency where they based all their phase calculations i.e. that's wave in the "quarter wave plate." So you put this filter in front of your light source and turn your camera to grayscale. Or you can just look at it and get used to the green as we once did with our green phosphor computer monitors.

If you want to get fancy you can set up an led that narrowly emits green light also.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Sansub2
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Re: Need help choosing objectives

#16 Post by Sansub2 » Fri Oct 22, 2021 10:27 pm

Pete,
I will try to clean the objectives again. Did it once with water, IPA and ear buds. I got it in a good deal locally. It was 225 CAnadian and the system was relatively clean (except the 40x annulus has a light leakage and one of the eye pieces lens was cracked internally. Otherwise it was in good shape). Image is below. Is the objectives made in Japan for this model?

https://flic.kr/p/2mDsLn2
https://flic.kr/p/2mDnnQY

About the dark background, i used the 100 annulus to create the darkfield effect. I do have dark field patches as well (from 15-22). Does the dark background looked good or bad? :). I bought G4 leds and using it in place of the halogen light in both microscopes. It is a 3W LED and drawing about 1-1.5W. I have ordered 7W COB version of it as the low power one seems not sufficient enough for 40x objectives (either that or I suck at high power imaging).

Regarding the phase telescope, I was saving it for the objective because i thought that would be the immediate need. If the recommendation is not to go with the fl or apo, then i can use it to buy the phase telescope.

Sansub2
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Joined: Wed Oct 20, 2021 3:34 pm

Re: Need help choosing objectives

#17 Post by Sansub2 » Fri Oct 22, 2021 10:31 pm

Hi Bram, thanks for the info. Trying to digest it :)

If I understood correctly, if I buy the item in the link below, place it on top of the light source and change camera setting to Grayscale to get the monochrome imaging. Is that correct?

https://www.ebay.ca/itm/T00-27mm-Quarte ... 632-2357-0

Never heard about it below and would to test it.

PeteM
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Re: Need help choosing objectives

#18 Post by PeteM » Fri Oct 22, 2021 10:55 pm

Sansub2 wrote:
Fri Oct 22, 2021 10:27 pm
Pete,
I will try to clean the objectives again. Did it once with water, IPA and ear buds. I got it in a good deal locally. It was 225 CAnadian and the system was relatively clean (except the 40x annulus has a light leakage and one of the eye pieces lens was cracked internally. Otherwise it was in good shape). Image is below. Is the objectives made in Japan for this model? . . .
That is a good deal for a phase scope.

If the 40x has dried immersion oil on it, neither IPA nor water will clear it. Just carefully inspect it first. If the scope never had a 100x objective, there's a good chance your efforts with distilled water and IPA will have cleaned it.

You have the later Micromaster model - made in China rather than Japan. Still a decent scope of about the same design and with OK objectives. I don't see the other side of the brightfield-only 10x, but it looks to be a plain rather than plan achromat? The original Japanese-made Micromaster (if memory serves) had both Japanese-made achromat and plan achromat objectives available and (again if memory serves) something like dark medium rather than positive low contrast. These were pretty good, just a bit below something like Olympus A and D Plan in my experience.

You might be able to use a pinhole to better see the alignment of the phase rings and phase annuli, short of springing for the phase telescope. Might set up an Ebay search - eventually one should show up very affordably.

Sansub2
Posts: 101
Joined: Wed Oct 20, 2021 3:34 pm

Re: Need help choosing objectives

#19 Post by Sansub2 » Fri Oct 22, 2021 11:24 pm

Thanks for the information. Here is the full set if the phase objectives. They all have PL and PHP markings. Don't know what is the last P in PHP.

Objectives:
https://flic.kr/p/2mDsmA2

Microscope:
https://flic.kr/p/2mDtwk2

Will try your pinhole suggestion..

PeteM
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Re: Need help choosing objectives

#20 Post by PeteM » Sat Oct 23, 2021 12:20 am

Looks like a very complete and decent scope. Since there is a 100x, you might check for immersion oil contamination on the 40x and others.

I believe the "PL" for these objectives means they are plan. The "PHP" may mean positive (rather than negative) phase contrast.

BramHuntingNematodes
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Re: Need help choosing objectives

#21 Post by BramHuntingNematodes » Sat Oct 23, 2021 1:30 am

No the quarter wave is already present inside the objectives you just need a green filter
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

VCRCleaningCassette
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Re: Need help choosing objectives

#22 Post by VCRCleaningCassette » Fri Nov 11, 2022 7:44 pm

Sansub2 wrote:
Fri Oct 22, 2021 4:53 pm
Thanks for the response Pete. Sorry, forgot to mention earlier that I do have a generic 20 plan acro objective. I compared the image quality of the phase objectives to the acromat plain from Amscope. The normal acromat image and videos are more crisp. The different is noticeable. Please see the comparison video below. Will try to upload the objectives image shortly(the file size is large)
Thread resurrection 8-)

Did you take the phase objective videos through the Micromaster? I just purchased the same Fisher scope and was curious what your camera setup looks like. Are you using one of the eyepieces, a relay/photo eyepiece, or direct to sensor?

Sansub2
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Joined: Wed Oct 20, 2021 3:34 pm

Re: Need help choosing objectives

#23 Post by Sansub2 » Tue Nov 22, 2022 6:41 pm

Hi VCR,

I just noticed your message.

Yes I did took videos. I didn't use the photo port though. I use my phone camera ( Samsung s21 ultra) which has better quality camera than the cheapo Usb cameras out in the market. It is easier to use as well. I have a 3d printer. So made the "sleeve" for the phone adapter. I can post pictures later.

Dennis
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Re: Need help choosing objectives

#24 Post by Dennis » Tue Nov 22, 2022 7:07 pm

PLAN: These objectives produce an image which is in focus from edge to edge. They are used for photographic work and are more expensive.

160: This represents the standard tube length of 160mm. Objectives with this standard are interchangeable between manufacturers.

PL or NH: These are designation of objectives used for phase contrast microscopy. A PL (positive low) objective produces an image of a specimen which is darker than the background, a NH (negative high) objective produces an image which is brighter than the background.

From another website-

DLL (Dark Lower Contrast) - Similar to the DL objective, the DLL series allows better images in brightfield and is often used as a "universal" objective in microscope systems that utilize multiple illumination modes such as fluorescence, DIC, brightfield, and darkfield.

Someone or someones in here keep saying a phase contrast objective looks less detail or something when used in brightfield. That is all I use on my Olympus phase contrast scope (PL) and use it mostly for brightfield. You tell me there is anything wrong with this- (I get fine results!)-
https://onedrive.live.com/?authkey=%21A ... 02&o=OneUp

If I were you I would go on Amazon.com or wherever and AmScope sells 20X objectives. I cannot, repeat, cannot live without a 20X objective on a microscope.
It is great for seeing many microbes that are mid sized up close such as Paramecium.

Geez I just noticed this is an old thread coming up again, well guess okay to reply.

Sansub2
Posts: 101
Joined: Wed Oct 20, 2021 3:34 pm

Re: Need help choosing objectives

#25 Post by Sansub2 » Thu Dec 01, 2022 12:38 am

VCRCleaningCassette wrote:
Fri Nov 11, 2022 7:44 pm
Sansub2 wrote:
Fri Oct 22, 2021 4:53 pm
Thanks for the response Pete. Sorry, forgot to mention earlier that I do have a generic 20 plan acro objective. I compared the image quality of the phase objectives to the acromat plain from Amscope. The normal acromat image and videos are more crisp. The different is noticeable. Please see the comparison video below. Will try to upload the objectives image shortly(the file size is large)
Thread resurrection 8-)

Did you take the phase objective videos through the Micromaster? I just purchased the same Fisher scope and was curious what your camera setup looks like. Are you using one of the eyepieces, a relay/photo eyepiece, or direct to sensor?

Sorry, took some time to respond. Please see pictures below.

I 3d printed a sleeve that that's my camera lens, sets proper distance from thr lens to eyepiece. This helps me set up the phone camera in the phone adapter in few seconds.


ImageDCD85E68-31BC-449D-8C61-D4DC48A74CF7 by San Sub, on Flickr

Image20221130_191835 by San Sub, on Flickr

Image20221130_191842 by San Sub, on Flickr

Link to phone adapter:

Cellphone Telescope Adapter https://a.co/d/icbgTyy

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