Monocular head completely loose on new microscope

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dragonblade
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Joined: Sat Oct 18, 2014 11:16 pm

Monocular head completely loose on new microscope

Post by dragonblade »

Ive ordered this monocular microscope via eBay.

http://www.ebay.com.au/itm/162645156577

I'm trying to set it up but the monocular head and attached eyepiece tube are completely loose and swivel around. It can also be easily detached as well. I can't see any way of tightening it. Would anyone here likely have some tips? This scope didn't come with much in the way of instructions. The only reference to setting up is attaching the eyepiece and that's it.

I'm going to contact the seller and see if I can obtain some more information from him / her.

dragonblade
Posts: 200
Joined: Sat Oct 18, 2014 11:16 pm

Post by dragonblade »

No information about how to attach the condenser as well. I also notice what looks like a circular blue filter supplied with the microscope but once again, there's no information about that or what it's used for.

Edit: Ive managed to tighten the monocular head. Now my next challenge is moving the objectives. The objectives are already installed but I can't rotate the nosepiece very well. According to the literature, it's a "quadruple nosepiece with accurate centering and positive click stops." I have great difficulty in rotating it. It's incredibly stiff.

Pau
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Post by Pau »

My advice is to return it if still possible, for that price you can buy better stuff
Pau

dragonblade
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Joined: Sat Oct 18, 2014 11:16 pm

Post by dragonblade »

Pau wrote:for that price you can buy better stuff
I'm quite surprised by that. Ive been looking around for microscopes for quite a while and Ive noticed features like fine focus adjustment and mechanical stage are usually offered on more expensive models. I may be a microscope novice but I have seen a number of microscopes in the same price range with less features. And for a long time, I was looking around for a second hand Olympus or Zeiss scope but Ive pretty much given up as I never had any luck - the used microscope market in Australia is way too small.

By the way, there's another odd thing I noticed (while viewing a slide.) I tried to use fine focus on a little object but the focus knob reached it's limit. Hence it was not possible to bring the object into focus.

Pau
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Post by Pau »

I tried to use fine focus on a little object but the focus knob reached it's limit. Hence it was not possible to bring the object into focus
Set the fine focus to about the middle of is travel and then focus with the coarse knob, this way you'll have enough room to focus.
If with all focus knobs at the uppermost position you can't reach focus you need to set the stopping screw
Image
Unscrew the big locking nut, unscrew some turns the bolt, the set the focus upper limit at the desired position, screw the bolt up to this position and screw the locking nut.
This is a desirable feature to prevent crashing the slides with the high magnification objectives
Pau

Pau
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Post by Pau »

Sorry, I need to explain it better:

First: your scope seems defective, the difficulty to turn the objective turret sounds very bad, this would be enough reason to return in

I ignore the kind of condenser (if any actual condenser at all), the light source seems pretty inadequate...could you explain your difficulties on how to attach the condenser?

AU $216.75 is really a low price but I've seen better new scopes in this price range.
Of course I would prefer to buy an used one of better quality
the used microscope market in Australia is way too small
I understand the issue, although I think that at Spain it is much smaller and I've found over the time interesting bargains on decent entry level microscopes and sometimes on better ones. (I've bought most of my used equipment from the USA where the market is really big and mostly some years ago when shipping and customs costs were less an issue than now...)
Pau

dragonblade
Posts: 200
Joined: Sat Oct 18, 2014 11:16 pm

Post by dragonblade »

Pau wrote: First: your scope seems defective, the difficulty to turn the objective turret sounds very bad, this would be enough reason to return in
I have reasonable strength (I do weight training) and on many occasions, Ive opened lids that are screwed really tight on jars (that other people have difficulty opening.) Yet I have so much trouble turning the nosepiece on this microscope once the objectives are clicked in place. But the crazy thing is my brother's wife (who has much less strength than me) can turn the nosepiece no problem. In actual fact, whenever I want to change objectives, I have to ask her to do it for me since most of the time, I can't do it myself.

Having said that, I am quite impressed with the quality of these semi-plan objectives. They are clear and sharp across the whole field of view (when viewing with the 10x eyepiece.) And I haven't noticed any colour fringing etc.
Pau wrote:I ignore the kind of condenser (if any actual condenser at all), the light source seems pretty inadequate
Out of curiosity, why do you think the light source would be inadequate? It's an LED light but I haven't been able to use it yet.
Pau wrote:could you explain your difficulties on how to attach the condenser?
I had made a mistake. I got the condenser mixed up with the LED power source. The condenser is already installed. And installing the power source seems straight forward but I don't have an adapter for the power plug. Supposedly, you can use batteries with it but I can't see any battery compartment. So I haven't been able to use this scope with electricity yet.
Pau wrote:AU $216.75 is really a low price but I've seen better new scopes in this price range.
Ive had the opposite experience. Ive looked at many brand new microscopes in Australia that are in a similar price range and generally, they're a bit lacking in features. So when ordering this one, I thought I was getting a bargain.

dragonblade
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Joined: Sat Oct 18, 2014 11:16 pm

Post by dragonblade »

Oh another thing....this microscope is meant come with two prepared slides, some AAA batteries and a charger. But I only see blank slides and no battery and no charger. Though of course hard to use batteries without a visible battery compartment.

Pau
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Post by Pau »

But the crazy thing is my brother's wife (who has much less strength than me) can turn the nosepiece no problem. In actual fact, whenever I want to change objectives, I have to ask her to do it for me since most of the time, I can't do it myself.
This seems really weird!

From all the tens of microscopes that have passed for my hands I only had two cases of difficult to turn nosepieces: one definitively damaged by teens very rough use and another very old with frozen grease that I managed to dismount, clean and re-lube, never in a new microscope!
Out of curiosity, why do you think the light source would be inadequate? It's an LED light but I haven't been able to use it yet.
Because it's a very small light source placed just under the condenser, I've seen this illuminator in many other models of the seller but a normal Abbe condenser would work badly with this arrangement: a collimated (almost parallel) bundle of light is what works better to illuminate the condenser.
Though of course hard to use batteries without a visible battery compartment
I guess that the batteries will be placed inside the big round part of the illuminator.
Pau

dragonblade
Posts: 200
Joined: Sat Oct 18, 2014 11:16 pm

Post by dragonblade »

I think I know what you mean by the supplied light being so small. I tried it with the 4x objective and it doesn't fill the whole field of view. Lighting is really uneven. I think the mirror works better overall with the lowest magnification objective. Plus I can see scratches in the glass on the lens of the light source. Not a good look. However, none of this is a problem when using the 40x objective. As I'm only viewing a very narrow space with the 40x, the light fills the entire field of view. And the scratches in the glass are no longer visible due to the shallow depth of field.

Strangely, I can't see any change in brightness when I open or close the diaphragm. Brightness stays the same regardless. The only substantial change I see is that at some point when I'm moving the diaphragm slider, I can see something dark passing through the field of view (blocking the light temporarily.) Then the image becomes bright again when I continue moving the slider in the same direction.

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