AmScope T490 options

[charlie]

After reading a bunch of the advice asked for and received here on MicrobeHunter.com Microscopy Forum, I had pretty much decided to buy:

http://www.amazon.com/AmScope-T490B-Mag ... cope+T490b

But the the WL16x objective seems more useful that the WL20x:

http://www.amazon.com/AmScope-T490A-Mag ... cope+T490A

But, but, the plan achromatic objectives seem like they would be nice to have:

http://www.amscope.com/compound-microsc ... tives.html


FYI, I a m a noob, retired and plan on amusing myself with the microscopy hobby.

I had thought of getting the darkfield option at this time too but that seems like it could wait until such time as I really need it? Same with any camera system?

Please tell me if you have any objections or suggestions to this? Go ahead, I have thick skin!

I also wonder if waiting for upcoming holiday sales will be worthwhile?

[mrsonchus]

My advice is to forget eyepieces above x10, they rarely offer anything worth having. The 'plan' objectives, if they're good ones, will give you a very big improvement in image quality, especially when photographs are being taken. The flat field of view is a huge bonus compared to the non-plan (i.e. just achromatic) lenses that have their clearly-focused area in a smallish circle in the center of the field of view.
When I moved to plan objectives the difference was significant, although this was accompanied by a huge upgrade in the quality of my 'scope, as I bought a new infinity 'scope with plan objectives. However, I'd choose the plan objectives before the x20 or x16 eyepieces every time. Hope this helps a bit.
Others here will be able to give you far more qualified opinion than mine, there are folk that know an awful lot about equipment and they'll soon answer your question I'm sure.
Good luck - that 'scope looks a cracker for the price.

[lorez]

Please tell me if you have any objections or suggestions to this? Go ahead, I have thick skin!

While this microscope is not at the top of the pile it should serve your needs adequately.

The biggest short coming is the triocular body that is "Simul-focal". The light is split in the body with no provision for selecting one path or the other (eyepiece vs. camera tube} so the light intensity is always less than the output of the 20W halogen bulb. This makes applications such as phase and darkfield a bit problematic. This is not to say they cannot be done, it means they cannot be done as well as possible.

This would not be my first choice if adding applications is in your future plans.

lorez

[charlie]

Thank you for the replies

This would not be my first choice if adding applications is in your future plans. lorez

Ouch, I guess I didn't have it figured out then. Now I am glad that I asked. I doubt (at this time) I will be willing to spend the money for phase but i did think i might enjoy microscopy enough to want to do darkfield at some point. I was not aware of the splitting of the light issue. Now that you point it out, I can see it. What would you recommend? I do think photography will be of interest.

[lorez]

What would you recommend?

This is a question that will certainly open the proverbial can of worms.

Since you are just getting started it may be wise to "keep it simple" until you find out that you really have the passion. There is a lot that can be done with a fairly simple system and if you find that you are going to stick with it you can always get better equipment.

Used instruments are always an option. Late model Olympus and Nikon are good choices. American Optical is also good. You must do your research when getting into the used equipment, but that does not mean that there is not a lot of very nice equipment available.

Special accessories like phase contrast and darkfield are nice, but in the beginning probably not necessary. An inexpensive camera may be a more valuable asset.

lorez

[charlie]

I guess I will use gekko's lights to illuminate the T490 then.

http://www.ikea.com/us/en/catalog/products/20169658/

Perhaps the led color won't be as much of an issue when combined with the halogen?

From what I have seen here, the T490 is pretty much entry level to this hobby and it seems to offer some expand-ability?

Used seems pretty risky for a noob; although this is right nest door!

http://www.swapauction.wisc.edu/Listing ... cope-39635

[gekko]

Charlie, welcome to the forum! It seems you have done your homework very thoroughly, I just want to say that I would not buy a special darkfield condenser at this point, as you can get excellent darkfield at the lower magnifications by using a simple darkfield stop made out of black paper or something similar. You can implement oblique illumination and polarized lighting easily and with trivial expense. But why do you want to combine halogen lighting with LED? If faithful color is important to your application, this may not be easy to do. Keep asking questions, and best of luck.

[75RR]

Hi charlie,

I guess I will use gekko's lights to illuminate the T490 then.

These lights are really for stereo scopes, they do not work well with compound microscopes (like the T490 or the Zeiss you showed) as there is very little room between the sample and the objective.

The T490 will be fine, despite the "Simul-focal", that would only potentially limit darkfield at higher magnifications.

The Zeiss looks tempting, but perhaps not as a beginners first microscope.
It is missing objectives and the reference to "Includes power supply (missing power coupling)" does leave a question mark as to whether the illumination is working.

Having said that, the microscope does look to be in general, in good condition.

It does have what looks like a Phase condenser - no small thing.
That would also give you darkfield with low power objectives, i.e. 10x and 16x.

If it is close perhaps you can go and have a look - lets us know what type of condenser it has.

If you have a spare $100 I would be tempted to put in a bid. Make it a project.

Meanwhile use the T490, it will take you a while to outgrow it!

[lorez]

Make it a project.

That's the trap when it comes to used equipment. Are you looking for a microscope building project or a microscope using hobby ? A complete, functional instrument from a source that can assure that it is in optimal working condition would seem to be the goal of the beginning hobbyist.

lorez

[75RR]

Are you looking for a microscope building project or a microscope using hobby ?

I did recommend that he get the T490, bidding $100 + - for the Zeiss as a long term project is not contradictory. One can do both.

[lorez]

One can do both.

As, I would guess, most of us do.

[Charles]

Used seems pretty risky for a noob; although this is right nest door!

http://www.swapauction.wisc.edu/Listing ... cope-39635

That is a Zeiss Standard 14 and has lots of potential but if you are close, I would go look at it. The phase condenser alone is worth the price of the scope if it is in good condition. The lighting for the 14 has a 6V 10W halogen light (plenty of light for that scope) and transformer built into the base of the scope and plugs directly to AC. So if the inards are intact, all you would need to do is splice in a plug and add some objectives. But...I think having a brand new scope working right out of the box is your best choice until you get used to microscopy.

Note: Looking at the serial number (47 09 16-9904/38) It appears to be a Standard 16 which is an upgrade version of the 14.

One can do both.

As, I would guess, most of us do.

No, I would buy the Zeiss!

[charlie]

Thanks for the welcomes and helpful responses gekko, 75RR and Charles !

I am thinking here we go again on the Zeiss! (I spend a lot of time rebuilding stuff.)

So, yes I will bid on the Zeiss if you pros advise it. (Sorry lorez, I am weak!)

I took some pictures:



The cut cord and missing objectives have me picturing a pissed off professor not wanting to fight with the Zeiss anymore!

[Charles]

Sometimes they clip the cord and take the objectives off so no one will walk away with the scope.

Keep an eye on ebay and Zeiss phase objectives come up fairly cheap at times.

[Charles]

Visually check the eyepieces against a white background to make sure there are no hazing around the edges which would point to delamination.

Rotate the coarse and fine focus knobs and make sure they function.

Also check the phase condenser. Take it off the stand (Rack the condenser all the way down and then just pull the condenser forward against the front pin and then tilt it out of the condenser holder) and rotate to each phase position and looking from the bottom check out the phase rings to make sure they are not peeling off. Make sure the iris works on the Brightfield position.

Everything from the pictures look realy clean.

[lorez]

(Sorry lorez, I am weak!)

No apologies necessary. The path you have chosen is no less interesting than any of the others and since you are getting started it will be an exciting learning experience.

lorez

[charlie]

Thanks Charles

I will go there shortly and check what you suggest but i don't understand what "Make sure the iris works on the Brightfield position" means. sorry

[charlie]

(Sorry lorez, I am weak!)

The path you have chosen is no less interesting than any of the others and since you are getting started it will be an exciting learning experience.
lorez

lol I am pretty certain I am ordering this too:

http://www.amscope.com/compound-microsc ... tives.html

Black Friday and such has me procrastinating.

[Charles]

The phase condenser has a diaphragm iris in the bright field position which is labelled 'J' on the conderser wheel. On the condenser outter ring there will be two half knurled knobs to facilitate rotating part of the ring which opens and closes the iris.

Also check the iris on the light port by turing right and left.

Check the objective turret, to make sure they rotate and stop at each objective with nice solid click stops.

[lorez]

The scope you have chosen is probably a good place to start.

While you are evaluating the Zeiss you may want to attach a cord so you can check the power pack. Also, look at the bulb holder and condition of the reflector mount. I recently modified a scope like this by adding an LED and the result was most impressive, so if the electronics are not in working condition there is still hope.

lorez

[75RR]

I took some pictures but didn't want to overload this forum:

http://s585.photobucket.com/user/charli ... t=4&page=1

If more pictures would help, let me know. The cut cord and missing objectives have me picturing a pissed off professor not wanting to fight with the Zeiss anymore! :)

When you say you took some pictures, do you mean you have gone to see the microscope or are you linking to the sellers pictures?

If you get a chance to see it (again?) - it might well look like this - from the images the condenser has a position 5 and a D position. So 7 in total: J (Brightfield) 1, 2 and 3 (Phase) 4 and 5 (blank) and D. (allows higher NA Darkfield)
Make sure the diaphragm iris at "J" opens and closes smoothly and everything looks like these images. In as much as they are similar.

To remove the condenser, first loosen the two screws at 10 and 2 o'clock behind it, then loosen the one at 6 o'clock below it. Make sure the stage is as high as possible and the condenser is at its lowest point. Do not scratch condenser lens!

[charlie]

Yes I visited the Zeiss and took those pictures.

Thanks for that pictoral explanation 75RR. I surely would not have succeeded in doing the tests you suggest without that!

I will go Monday to do the tests you and lorez suggest. (Assuming no one stops me. )

[einman]

If you are patient and diligent you can find excellent deals on E-bay. I have purchased in the last 2 months 3 microscopes that were in excellent condition all three for less than $450 total.

A meiji ML2000 in excellent condition- quite a solid built scope.
a Reichert Microstar 410 with phase-contrast-complete. Very solidly built and though very dirty cleaned up like new.
an Olympus BH-2 with D-plan objectives in like new condition.

I often purchase for resale to fund my hobby. Which constantly tugs at my purse strings!!!

[Charles]

Most of mine are from ebay. The hard part is recognizing a particular microscope, brand, features, condition and price, but it can net you some very nice name brand microscopes for pennies on the dollar. I just got a B&L research, Zeiss standard 18 and a trincoular AO cycloptics stereo with light base (on it's way) which averaged about $100 each. I enjoy the collecting microscopes, especially the older black and brass ones. Sometimes you get started by buying one and want a particular part for it, like say a phase unit but searching around, it's cheaper buying a parts scope with it on it than just the phase unit by itself. Enjoy the wonderful journey of microscopy which ever direction it takes you.

[75RR]

Another thought on the Phase Condenser.
The base rotates left or right to each of the 7 positions, it should move firmly but smoothly, and like any precision instrument it should not be forced. The location of the engagement position is at 3 o'clock. It is a vertical white line. With position "J" at 3 o'clock, the diaphragm iris of the brightfield position will be visible in the 12 o'clock aperture.

[75RR]

Not saying to get this one, but it is one of the items you want to keep an eye out for if you do get the Zeiss.

http://www.ebay.com/itm/Zeiss-Siedentop ... SweuxWR8B3

[einman]

The precision, construction and design of some of the older scopes and in this case the phase condenser is quite beautiful! One reason why so many of us are attracted to older scopes.

[unseen4ce]

What do you guys think of this?
http://www.ebay.com.au/itm/Olympus-Mode ... Sw~OdVePcV

Olympus seems to use a different system for phase contrast, as it has a '0' rather than a 'j'.

[Charles]

What do you guys think of this?
http://www.ebay.com.au/itm/Olympus-Mode ... Sw~OdVePcV

Olympus seems to use a different system for phase contrast, as it has a '0' rather than a 'j'.

Different makers used their own abbreviation for the open or bright field position. AO/Spencer also uses 'O', Leitz uses 'H', Nikon uses 'A', Zeiss uses 'J'.

IMO, $2000 seems a bit much for a used phase computer system.

[75RR]

To add to the fun: What looks like "J" is in fact the German-style engraving for "I" and marks the Iris position.