MicrobeHunter.com Microscopy Forum

75RR wrote:Could you post a photo of a larger subject (an alga for example) with the field diaphragm in view (just visible along the edge of the field of view) and sharply focused.

x6,3 obj:

Field diaphragm sharply focused (50% of the field of view): https://image.noelshack.com/fichiers/20 ... 195050.jpg
Field diaphragm sharply focused (90% of the field of view): https://image.noelshack.com/fichiers/20 ... 195432.jpg

Both pictures were taken with the condenser's diaphragm opened at 90%. Sorry for the very low quality...

It still looks rather uneven. Have you tried to focus the filament per my previous post + image on the condenser diaphragm? That might help.

Thanks for the quick reply 75RR ! Indeed, there are patches of bright light in the background. I did not try yet to focus the filament, because I wanted to show you how it was before trying it. Here were the steps:

1) Remove any opaque filters that may be in the light path.
2) Close the condenser iris completely
3) Place a mirror or slide under the condenser, angle it so that you can see the closed iris
4) You should be able to see the filament coils reflected on the condenser iris. (This is the Front Focal Plane)
5) If no filament coils are visible or they do not look sharp you need to move the light source either in or out until the filament coil is sharply focused.

Actually, I don't know if there are an opaque filters, and how to remove them.

image on the condenser diaphragm

Do you want a picture of the condenser diaphragm through one removed eyepiece ?

Just had a look at a connector tube which is similar to the one you have, the diffuser/opaque filter is incorporated in it. It can be removed but not worth it at the moment.

What I am thinking is that the mirror or the lens which is part of the field housing is broken. You may have to take it off.

The Field Housing is held in by two screws.

1) Take anything that may fall off when you turn the microscope on its side off first.

2) Mark the Field Housing's position with a pencil so that you can place it in the same position again.

3) It comes out through the top of the base so if you are holding the microscope upside down or nearly (to get to the screws) be careful that it does not pop out and hit the floor.

I can't say I'm not struggling on this one... I don't know if what I see is the filament or something else. As you will see, the image is repeated quite a few times, compared to your's on the slide.

https://image.noelshack.com/fichiers/20 ... 211326.jpg

Glycolyse wrote:I can't say I'm not struggling on this one... I don't know if what I see is the filament or something else. As you will see, the image is repeated quite a few times, compared to your's on the slide.

https://image.noelshack.com/fichiers/20 ... 211326.jpg

A few months ago I struggled with the field aperture, the problem was that the mirror detached from its 45degrees holder plate and in addition, the mirror itself was worn out - it was (apparently by mistake) a second-surface glass mirror. And the reflecting surface had deteriorated. Aided by close support from 75RR, Apochronaut, MicroBob and others, I replaced it with a first surface metal mirror, quite cheaply and the illumination improved tremendously. So it can be solved.

Oh my, guys. I had a good laugh . Indeed, there were patches of bright light in the background.

But do you know why ? Well, here's why: https://image.noelshack.com/fichiers/20 ... 013043.jpg

Yeah... There were these small things from the packaging beneath the microscope. Some were between the light path (from the halogen bulb to the mirror). No wonder why the light wasn't evenly distributed

Now, the light is brighter and evenly distributed. The quality of the image increased too !

Moss, 6,3x obj: https://image.noelshack.com/fichiers/20 ... 013549.jpg

I like simple solutions :) Well done!

Thank you 75RR !

I took some green marine algae samples today. Here are some photos.

obj x16 - Sample 1 - Focus stacking of 20 images.



obj x40 - Sample 2 - Focus stacking of 20 images.



It's not perfect and everything, but I'm fine with the result. What do you think ?

By the way, the x16 obj and the x40 bj seem to be blurred, especially the x40. I think they need to be cleaned (as well as the oculars probably). I found on one thread of this forum a pdf of Zeiss named The Clean Microscope - There are a lot of informations, so I will take time on this one. Every tip for cleaning my objectives and oculars are welcomed !

Looking much better. Nice oblique!

I wonder if you can notice a difference in the brightness if you move the bulb holder in and out a bit.

If you can notice a difference try for a bright yet even illumination.


As to cleaning optics 'The Clean Microscope' is an excellent resource.

Always good to clean used objectives (and eyepieces if dirty) when you first get them - that way you know where you stand.

Do not clean them too often though, make sure you cover the microscope and use a blower to remove dust.

The exception of course are oiled objectives which you must clean every time.

I use absorbent paper to remove most of the oil first (tap do not wipe) then use cotton swabs (see page 7) with a drop or two of isopropanol.

Do not use swabs more than once. Discard and use a new one after a single use. Use as many as you need. Breathe on lens with last one, use dry.

Thank you 75RR !

I think I achieved Phase contrast on both x16 and the x40 objectives:

x16 obj: https://image.noelshack.com/fichiers/20 ... 212629.jpg
x40 obj: https://image.noelshack.com/fichiers/20 ... 213105.jpg

There is a bright halo on every subject. It's a bit messy since I don't have a Phase telescope, and not correctly focused, but wanted to know if Phase contrast looked like this.

That looks about right.

Did you order a Phase telescope yet?

For phase contrast, a different specimen would be better. Cheek cells, or protozoans (slowed down to ease the viewing) - a truely thin and transparent specimen would be better indicatives of the quality of phase contrast than the algae.
In my opinion, the alignment of the condenser is not optimal.

75RR wrote:Did you order a Phase telescope yet?

I won't be able to order anything before the end of February. During this time, I'll check for a few things on Ebay/other websites:

- Zeiss trinocular head
- Zeiss oculars
- Phase telescope
- Zeiss Lens Cleaning, Isopropanol
- Zeiss Phase Contrast x60 dry objective (160)
- 8 Form test plate of diatoms from Mr.Klaus D. Kemp, which 75RR suggested in another thread
- (...)

Hobbyst46 wrote:In my opinion, the alignment of the condenser is not optimal.

Thank you Hobbyst, I definitely need a Phase telescope I guess.

1. Phase telescopes have been recently posted "for sale" by forum member Scarodactyl.
2. Dry 60X phase objective: There is a Zeiss Planachromat 63X0.90 ph3 objective, its working distance is very small (see the brochure "Zeiss Optical Systems" p. 53), might be difficult to use.
3. Zeiss occulars - the WF, high eyepoint (for glass wearers) version are much better than the non-WF version.

If you can borrow 25 euros from a kindly soul there is this one in Poland. They do not come much cheaper than that. PZO is one of the very good brands.

https://www.ebay.co.uk/itm/23-2mm-Phase ... :rk:7:pf:0

You might also want to call in several xmas + birthday gifts in advance:

https://www.ebay.co.uk/itm/Zeiss-Micros ... :rk:2:pf:0

Hi everyone,

Is this item good enough to clean my objectives and oculars ? https://www.amazon.fr/Alcool-Isopropyli ... sopropanol



Otherwise, where do you get yours ?

Glycolyse wrote:Hi everyone,

Is this item good enough to clean my objectives and oculars ? https://www.amazon.fr/Alcool-Isopropyli ... sopropanol



Otherwise, where do you get yours ?

1. This is good enough for your purpose; 99.5% or 99% are likewise good enough. Have not tried lower grades; 70% alcohol may contain too much water.
2. I got mine from a store that caters scientific experiment equipment to schools. It is available from any chemical supply house, but probably not a small quantity.
3. In view of the hazards of the stuff, I would strongly suggest :
a) purchase and store at home only a small amount - say 0.5 liter or 16Oz. This will suffice for a very very long time.
b) store in a well-closed bottle in a ventilated place, preferably a cabinet that does not get too warm. Ordinary house temperatures are OK.
c) the storage place should be out of the reach of children.
d) for each session of use for microscope work, pour only a small amount - say, 10-20ml or less - of the alcohol into a small flask or container, so the
main quantity stays in the closed container all the time.
e) avoid pouring or using near open fire, cooking gas flames, etc, or electric sparks.
f) use in a reasonably ventilated place - not in an all-closed space.
g) as a backup safety measure against spillage, put a glass/metal/resistant/ plastic wide flat container (tray with raised rims, a backing plate etc) directly under the alcohol bottle (the bottle stands inside the container), so if the bottle is cracked or leaking, at the worst, the liquid will be contained and not spread around.
4. The alcohol is fulluy miscible with water.

Thanks for the tips Hobbyst. Is there anything to add in order to clean my microscope's objectives & oculars ?

Most welcome!
Microscope parts can suffer from over-cleaning of the glass surfaces. Blow away the dust first, inspect surfaces through an inverted eyepiece that serves as magnifier, against sideways light. If further cleaning is needed, exhale on the glass to cause water condensation, then gently wipe with lens cleaning tissue or lens cloth (can be obtained from eyeglasses shops). One-way strokes only, not back and forth movements. Never rub a dry glass surface.
Oil and grease are removable with the isopropanol or petrol-ether (gasoline, octane etc) - but use sparingly. Apply with a Q-tip or a moistened lens cleaning tissue. In very difficult cases xylene can help, but apply it very very carefully, very sparingly, since it can dissolve old optical cements.

I find small spray-bottles (where you finger provides the propulsion) are great for convenient quantities of IPA, acetone, xylene, methanol etc. I use a weaker solution of IPA with some aqueous antistatic agent for my spectacles!

Thanks both.

In this video, Maintenance is showed: https://www.youtube.com/watch?v=jM2lVHa ... x=4&t=337s

It looks about right for me. Yet, he didn't show the cleaning of the objectives. Is it the same process ?

Hi everyone,

On my Zeiss condenser (46 52 70), I noticed there were 3 big lenses, which I think are slots for rings, such as D-stop etc. Ideally, I'd like to purchase some filters to see the differences between them.



The issue is the filters have a precise diameter (30, 31, 35mm etc.), and I can't tell what diameter my condenser's slots are. I can't find anything by typing the the number of the condenser on google. How can I know the diameter then ?

Update with pictures of the said-slots:

One with a lens:



The other one, above this one, without a lens:



Anyone has an idea ?

Zeiss filters are 32mm

Thanks ! I didn't know Zeiss condensers' filters were standardized.

I just received Isopropanol solution and a dust blower, gonna clean everything for the first time

Glycolyse wrote:Thanks ! I didn't know Zeiss condensers' filters were standardized.

Of the two auxiliary swing-out parts that you show, the top one contains a lens that is used to fill the low magnification objectives with light. That lens is fixed, not easily removeable. The bottom one is a filter carrier. I hope that Rheinberg and other special effect filters in that carrier will work for you. On my setup it did not.

I had thought that by "empty slots" you meant positions within the condenser turret itself. These might serve better for Rheinberg and other special effect filters, since they are at almost the same plane as the iris aperture. However, their diameter is not 32mm as far as I recall.

I didn't know that, thanks for the clarification Hobbyst !

I have one question. When looking through the x40 objective, the subject seems blurry, at any focus point given. As I received my isopropanol and the dust blower, I could clean my eyepieces, objectives and condenser correctly. However, the blurry aspect still exists. I remember while looking at a Motic BA210E-LED microscope, it was not the case.
- Was it because the subject was "bigger" ? (Elodea sp. compared to observing diatoms)
- My eyepieces are not the original ones (Chinese)
- Halogen light ?
- Wrong cleaning process ?
- Wrong setup of the microscope (Condenser height, etc.) ?
- ...

While I look at diatoms pictures from other members (such as 75RR, but it's DIC so I can't really relate with this technique),it looks like the subject shows good details, when mine doesn't.

I'd like to fix this "issue", if possible, because I bet it comes from me.

Maybe I should post a photo of a subject observed from a x40 objectif.

You should be able to focus all your objectives sharply.

If the problem is just with the 40x then the objective itself is most likely the cause.

Show us a photo taken with it and also a photo of the objective itself, get as close an image of its lens as possible.