COMPARING CORRECT ACHRO OBJECTIVE VS PLAN ACHRO AO SPENCER

[stjepo]

I am sure I am doing something that for the purists will be considered 'no kosher', please do not be offended by it.

You decide which looks best.


I take this picture in a AO Microscope that I was able to repair.
(Bear in mind I 'know' very little about AO microscopes)

Regards

[Hobbyst46]

As they are, the two pictured seemed to me very similar, although the left one is sharper. And both show about the same chromatic aberrations.
The colors in the right picture are slightly darker.
So I copied them and inserted in a picture processing software.
IMHO, the right picture - the one taken with the AO objective - is as a whole slightly out of focus. A focusing issue - not a problem of the objective. The focus seems to me uniform across the FOV.
Also, the background appearance is better in the right picture. So, by a marginal amount, I would prefer the AO objective, but re-check the focusing.

[stjepo]

Thanks for your comments, helps a lot. I will re-check the focusing.

For the 4X I made some alterations in the stage and in the size of the pictures to compare.

[stjepo]

For the 40X I made some alterations in the size of the pictures to compare.

[Hobbyst46]

For the 4X I made some alterations in the stage and in the size of the pictures to compare.

1. I wonder, why alter the stage for the 4X or for any other objective?
2. The left 40x picture seems to be slightly out of focus.
I must admit, that I do not quite follow the rationale of these comparisons, given the difference (finite vs infinite) between the objectives. Why hybridize?

[stjepo]

The last one 100X. The AO objective is in a very bad shape. I can not focus it more than that. Looks like it has small crack in the glass.

" I do not quite follow the rationale of these comparisons,"


I have no other way to compare till I get the proper eye pieces for the AO. I do not mean to use finite optics in infinite microscope. I do not see big differences (probability my 'ignorance').


My objective is to get sharper images to make pictures.

Regards

[Hobbyst46]

The last one 100X. The AO objective is in a very bad shape. I can not focus it more than that. Looks like it has small crack in the glass

To inspect the objective: if you have a phase telescope, remove an eyepiece from the head, insert the phase telecope, and inspect the objective through it.
Better still, if you have access to a stereomicroscope, clam the objective vertically on the stage, illuminate it brightly from below (not all stereos have this option), focus on the objective lenses one by one and inspect.

[stjepo]

I did as you suggested.

4X perfect,
10X perfect,
40X in hemispherical front lens, black paint is stripping and now light gets through out a bigger area.
100X: the front metal assembly housing looks rusted and breaking apart (brownish spots) now light gets through out a bigger area. In the hemispherical front lens looks like small lamination. Maybe the ghost shown in the picture? Can it be fixed?

Thanks for the help,

Regards

[Hobbyst46]

I did as you suggested.

4X perfect,
10X perfect,
40X in hemispherical front lens, black paint is stripping and now light gets through out a bigger area.
100X: the front metal assembly housing looks rusted and breaking apart (brownish spots) now light gets through out a bigger area. In the hemispherical front lens looks like small lamination. Maybe the ghost shown in the picture? Can it be fixed?

You are most welcome.

About the spider's feet images: I would not base any practical recommendation (like upgrade or not) from these images until they are tested with the
proper AO eyepieces.

Sorry, I know nothing about objective repair. But may I suggest that you post photos of the suspected 100x (and 40x?) objectives, with close-ups on the faulty areas, and please indicate if these are the CORRECT or the original AO objectives? This information can help other members to lead towards a solution.

[stjepo]

The Correct objectives are in perfect condition. I am talking always about the Plan Achro AO Spencer which where supposed to be superior.


Regards

[Hobbyst46]

...may I suggest that you post photos of the suspected 100x (and 40x?) objectives, with close-ups on the faulty areas

Sorry, I just recalled that you have already posted photos of the objectives, so I looked at them again. These photos IMHO do not indicate that the lenses are faulty. They do show some staining, or "rust" on the metal top of the objective. This is not rust! rust is iron oxides, and objectives are made of brass. So, maybe some other corrosion. Perhaps a previous user "cleaned" the objective with an ammonia-containing cleaner, or just dipped the objective in some liquid and left it to dry without cleaning. So I cannot say anything. What you identified with the stereo microscope counts.

Yet, the optimal use of the infinity corrected microscope is, as Apo explained, with AO optics all the way, down and up. When you finally have the AO eyepieces, if they work well with the 4x and 10x (and maybe the 40x as well), and if you still want a 100x objective (many people never use them!) then you might want to buy a new high-mag objective to complete the set.

Another option is use the CORRECT objectives on the AO scope. The only possibility it will yield good results is by luck, coincidence...whatever eyepieces are there...

But I would be patient and try to enjoy the microscope with a variety of different specimens. After some time one knows better in which equipment to invest.

[stjepo]

After some time one knows better in which equipment to invest.

Yes, and thanks for the time you are taking to help me.


Regards

[stjepo]

Yet, the optimal use of the infinity corrected microscope is, as Apo explained, with AO optics all the way, down and up. When you finally have the AO eyepieces, if they work well with the 4x and 10x (and maybe the 40x as well), and if you still want a 100x objective (many people never use them!) then you might want to buy a new high-mag objective to complete the set.

The AO eyepieces have arrived (AO optics all the way, down and up)... I have used them to see the 4X, 10X and the 40X and the 100X... the first 3 ones work very well... but also work well with the HWF10X that I was using, no difference (I do not mean to offend no one, please) and both, also, work very bad with the 100X.

Maybe is true what is said here:

"Eyepieces are quite forgiving can be used interchangeably on 160mm TL and Infinity corrected scopes with good results for instance, or often, between scopes of different makers. A very practical, simple introduction to microscope eyepieces can be found here. But don't miss reading the sections at the Olympus Resource Site and the Nikon's Microscopy Site. Eyepieces designed for telescopes must meet differing needs than those for microscopes, but even so, a very interesting piece is found here.

*Note: The 'purist' in me wants to note that the very best, optimum results will be obtained by using the eyepieces specifically made for each objective set (e.g. a Cat# 146 10x eyepiece on a 160mm TL Series 2 scope, a Cat# 176 10X eyepiece on an infinitely corrected Series 10 scope, etc.) -- but the 'practical side' of me says it really, truly doesn't make a heck of a lot of difference -- use what you have. But if you are wondering what the differences might be between different brands of eyepieces, Mervhob of Yahoo's Microscope Group has furnished the useful information below (also see Mikrofibel page 55)"
Copied from (https://user.xmission.com/~psneeley/Per ... pieces.htm) (~psneeley/Personal/Eyepieces.htm)

My honest opinion (probability based in may ignorance), is that there are not big differences between the Correct Achro objectives and the AO Pan Achro objectives, (4X, 10X and the 40X ) but in the case of the 100X objective... the Correct is by far, superior. (I have followed all the instructions in the manual and all the advice given to me for the correct use of the AO Spencer microscoped).

What am I doing wrong?

Regards

[Hobbyst46]

Maybe is true what is said here:
"Eyepieces are quite forgiving can be used interchangeably on 160mm TL and Infinity corrected scopes with good results for instance, or often, between scopes of different makers...But if you are wondering what the differences might be between different brands of eyepieces, Mervhob of Yahoo's Microscope Group has furnished the useful information below (also see Mikrofibel page 55)"
Copied from (https://user.xmission.com/~psneeley/Per ... pieces.htm) (~psneeley/Personal/Eyepieces.htm)
My honest opinion (probability based in may ignorance), is that there are not big differences between the Correct Achro objectives and the AO Pan Achro objectives, (4X, 10X and the 40X ) but in the case of the 100X objective... the Correct is by far, superior. (I have followed all the instructions in the manual and all the advice given to me for the correct use of the AO Spencer microscoped).

What am I doing wrong?

1. Being a non-expert myself, certainly not on AO microscopes (unfortunately they are very rare here), I do not see anything "wrong" in what you are doing. The 4X, 10X, 40X work fine in your opinion - great!
2. The AO 100X is faulty in your opinion. It can happen. If you identified, by means of the stereomicroscope, that the glass is suspect of an optical/mechanical fault - it may be so disregarding any eyepiece. Perhaps a replacement AO 100X objective will not be very expensive.
3. "Eyepieces are quite forgiving..." I agree, but that is not a 100% statement. More important, IMHO, is the difference between eye view and camera view. Our brain is more forgiving than the digital camera. The camera is more objective, since it provides raw data, does not process the image and manipulate it.
Example: I am using Olympus eyepieces with Zeiss objectives (160mm scope, no tube lens). The view is superb. However, the same eyepiece, or even an FK Olympus eyepiece (a photographic lens, still for 160mm optics) create ugly chromatic aberrations when placed in the photo tube.
Another example - please have a look at the active post "Wild Plan Fluotar" by forum member Grahame in the Active Topics of the Forum. The compatibility of eyepieces and objectives is causing a lot of confusion. A search through this Forum and macrophotography.net with the keyword "eyepiece" can demonstrate it.
4. I would judge the performance of an eyepiece-objective combination with a variety of model specimens, for example, specimens of less contrast, very flat and thin, regular grids - cells, stage micrometers etc, take photos and post them. More comparison photos can help others evaluate your results.

P.S.
5. - are the above images taken through the AO trinocular head on the AO microscope?
6. - The AO 100X is an oil immersion objective.
7. - Last question - and please do not be offended: I wonder about the photo above, of the spider's leg/foot under the 100X. Such objectives have a very shallow depth of focus. I have never looked at a spider's foot before (the spider shrinks and pulls his leg away from me ) but a lot of the object is in focus. Was that taken with a coverslip and immersion oil?

[stjepo]

Maybe is true what is said here:
"Eyepieces are quite forgiving can be used interchangeably on 160mm TL and Infinity corrected scopes with good results for instance, or often, between scopes of different makers...But if you are wondering what the differences might be between different brands of eyepieces, Mervhob of Yahoo's Microscope Group has furnished the useful information below (also see Mikrofibel page 55)"
Copied from (https://user.xmission.com/~psneeley/Per ... pieces.htm) (~psneeley/Personal/Eyepieces.htm)
My honest opinion (probability based in may ignorance), is that there are not big differences between the Correct Achro objectives and the AO Pan Achro objectives, (4X, 10X and the 40X ) but in the case of the 100X objective... the Correct is by far, superior. (I have followed all the instructions in the manual and all the advice given to me for the correct use of the AO Spencer microscoped).

What am I doing wrong?

4. I would judge the performance of an eyepiece-objective combination with a variety of model specimens, for example, specimens of less contrast, very flat and thin, regular grids - cells, stage micrometers etc, take photos and post them. More comparison photos can help others evaluate your results.

BTW - are the above images taken through the AO trinocular head on the AO microscope?

As always, very good advice. Yes, the ones on the right where taken through the AO trinocular head on the AO microscope. I will read about "The compatibility of eyepieces and objectives is causing a lot of confusion" in the forum.

Thank you,

Regards

[Hobbyst46]

I edited my last response by adding another question (P.S.). Just meaning to help.

[stjepo]

6. - The AO 100X is an oil immersion objective.
7. - Last question - and please do not be offended: I wonder about the photo above, of the spider's leg/foot under the 100X. Such objectives have a very shallow depth of focus. I have never looked at a spider's foot before (the spider shrinks and pulls his leg away from me ) but a lot of the object is in focus. Was that taken with a coverslip and immersion oil?

6. Yes, it is an oil immersion objective.
7. Ja, ja , I never get offended, especially with someone who tries to help me. Yes, when the picture was taken it had a coverslip and immersion oil.

Thank you,

Regards

[Hobbyst46]

Out of curiosity, since unfortunately I never met or worked with AO, I just looked at eBay, for example:
https://www.ebay.ca/sch/i.html?isRefine ... ro&_sop=15
And other huge selection of AO optics at half or less the price of corresponding German/Japanese optics...

[stjepo]

Yes they are cheaper, maybe the market doesn't know to much about microscopes and are as good as the expensive ones, I have no idea (maybe there is an study about it) ...

Also I have no experience on AO microscope. Is the first one I owned and repaired (hope I have done in the proper way). I think its illuminating system is very superb.

Up to now the AO objectives I have, work similar to the Correct objectives of my 'cheap' Seiwa (please lovers of the AO, bare in mind that this is only my personal and 'ignorant' opinion, I am not an 'expert' and is before I make more tests that Hobbyst46 has asked me to do).

The 100X (that not necesarilly represent all the AO 100X in the world), is worse that the Correct objective by far. (Using AO eyepieces)

Regards

[stjepo]

Here two pictures of the same subject, one in the Seiwa 4X and the other in the AO 4X



Regards

[stjepo]

Another set of 4X AO and Seiwa



Regards

[stjepo]

Another set of 10X AO and Seiwa



Regards

[apochronaut]

Comparisons of this type are sometimes valuable, if they are done like a mini-science experiment, with variables eliminated or at best kept to a minimum. It's always helpful if the experimenter knows what they are doing as well, if only in terms of trying to eliminate spurious elements that might alter the results.
Looking at the bulk of the pictures you have been regularly plying this thread with, I would suspect that there is some sort of problem in either the set up or even a defect in the optical train of the AO 10. The images have fairly consistent problems that should not be there with such a system; a skewed crescendo of ca in one sector of the field, lack of resolution and even lowered contrast and what appears to be flare. You can't really have a competition when one of the participants is blind, can you, not to mention the referee.

Rather than comparing , you might try putting your energy into determining what is fouling the imaging with the 10.

[stjepo]

Thank you Apochronaut for your answer. Please clarify me if the following comments apply to the images of my last 3 messages …

… some sort of problem in either the set up or even a defect in the optical train of the AO 10. The images have fairly consistent problems that should not be there with such a system; a skewed crescendo of ca in one sector of the field, lack of resolution and even lowered contrast and what appears to be flare….

…if so, could you show me the defects you find in them as I did put all the ‘energy into determining what was fouling’ the system and these are the results?
Although my intention was not to make a ‘mini-science experiment’ I did keep, as much as I could, the ‘… variables eliminated or at best kept to a minimum…’ , my objective is to see if my images improve with the plano achromats even if you imply that as an experimenter I do not know’… what they are doing as well…’

Rather than comparing , you might try putting your energy into determining what is fouling the imaging with the 10.

And if I don’t compare, then, which is the best way to do it taking into account that my experience with microscopes is short?
Do you have any additional info or tests that can help me?

Finally, I do not understand what are you trying to say with the following sentence

You can't really have a competition when one of the participants is blind, can you, not to mention the referee.

Do you imply that as a referee I am not qualified or I am cheating in the results because of the blind competitor (I assume that you refer to the AO10)? To my belief that does not make sense because the only thing I did, in my last three messages, was to show the images of my photographic sessions with each microscope in similar conditions. I did not evaluate or comment the results because I wanted the help of the people of the forum that are mucho prepared than me. Do you find big differences?

Regards

[photomicro]

I am a little confused as to what we are looking at here, especially with the two x4 objectives. Are they both on their own stands?

I ask because the field of view is very different, and realise this could easily be down to how the camera is mounted, and what eyepiece/relay lens is being used. Or cropping of the image.

Would be useful to know if the fields of view when looking through the eyepieces in normal use is so different.

[mrsonchus]

Hello, I've been following along with this thread too, as I'm,like just about everyone here, always interested in comparisons that add to experience and knowledge as this one promised to do...
Unfortunately, try as I may, I can't seem to understand your rationale or 'test' conditions. I find myself agreeing with apo' (a hugely experienced and competent fellow in the realms of equipment specification and comparative performance) and photomicro.

I suggest that you may start again with a clear statement of what you are trying to achieve, your rationale after consideration of the 'problem' as you define it and your proposed method to test your rationale against reality.

As presented I can't personally make 'head nor tail' of your images as there are so many factors, both stated and not, that are varying it seems quite wildly - the 'scope, the eyepieces, the focus, the focused point/area of each image - etc....

Please don't be offended but as presented this thread is getting more confused as you add more images without any coherent strategy, explanation or comparisons of your 'results'.

Please don't be offended by apo's comments above, rather read them carefully because they make perfect sense, they're certainly not in any way an attempt to accuse you of cheating etc etc - even the suggestion that this is the case is unpalatable I'm certain to folks following this potentially interesting thread.

Please try to approach this with more structure and coherence;

1) Define what you see as the 'problem' or aspect that you are interested in.
2) Consider this and give a suggestion of what may be it's cause (one cause at a time is best).
3) Define a strategy to test this theory - i.e. how you will go about any tests and most importantly as apo' suggests, how you will as much as you are able, confine the test/s to the one variable at a time whilst keeping the rest constant.
4) State your results or interpretation of each test clearly and the conclusion that you may be able to make for the variable tested.

Without a planned and disciplined approach to these comparisons you will be in danger as apo' says of simply 'plying' this thread with images that have very little value. The above advice is really just another way of suggesting also that an approach such as that taken with a science project would be helpful, not insulting.

In a nutshell, you need to have a think about what you're trying to do here and how you're going to do it - as it stands this thread is becoming somewhat incoherent, which is unfortunate as you have an interesting 'problem' and clearly a huge level of enthusiasm.

regards, John B.

[MichaelG.]

download/file.php?id=12322

^^^ This one in particular, I find to be a very pleasing image, and I am sure that objective will serve you very well for this style of work.

However, as the others have noted: If you [and if we] are to understand what's going-on, and thereby learn something from them, your tests do need to be more methodical.

It's tedious to do, but very worthwhile.

MichaelG.
.
For a 'masterclass' in comparative lens testing, have a look at this site:
https://www.closeuphotography.com/lens-tests/

P.S. it's worth a general browse around that site ... where you will also find gems like this:
https://www.closeuphotography.com/seven ... objective/