Anyone have an Amscope PCT 120 phase contrast condenser?

Everything relating to microscopy hardware: Objectives, eyepieces, lamps and more.
Message
Author
billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Anyone have an Amscope PCT 120 phase contrast condenser?

#1 Post by billporter1456 » Thu Jun 22, 2017 4:31 pm

I recently sold my Nikon Labophot and related equipment (a couple of USB cameras and lots of LED stuff) because I had not used it in almost a year and didn't anticipate getting back into the microscopy hobby in the future. I did keep my $200 Omax scope and a 3 MP USB camera just in case I ever wanted to again peer at pond water. Well, not long after selling the Nikon stuff I scooped up some pond water and enjoyed spending an hour or two making a video of a couple of rotifer eggs hatching. And then, as you might guess, I started looking at eBay microscopy items.

I ran across a used Amscope phase contrast condenser that I thought would fit my little Omax and it was only $168 with 4 plan phase contrast objectives. Retail for this kit is about $600 from Amscope. The seller did not offer returns, but I thought it was worth the gamble to get the kit and play around with it. When it arrived a couple of days ago, the objectives looked in good shaped and gave better images than the objectives I had on the Omax, so things were looking up. Then I noticed that the annulus for the 10X objective was lying loose in the case. I had a little spanner wrench, so it wasn't hard to put it back in place. By the way, the 10X annulus seems identical to the 20X annulus and I confirmed this as I went through the alignment procedure.

Here's the problem. As I rotated the turret, it rotated freely, BUT THERE WERE NO CLICK STOPS. I had to just carefully position the turret, at the 20X position for example, and then align the phase ring and annulus. As long as I didn't touch the turret, I could get decent phase contrast. Since the 10X and 20X use identical annuli, I could switch back and forth between those two objectives with relative ease.

Removing the little silver screw on the side of the turret, I can see that there must have been a tiny part of some sort that "clicks" into one of the five small slits in the plate that holds the annuli. If someone who has this condenser is willing to remove the bottom plate of the device and maybe unscrew the little silver screw, perhaps they can see the part(s) I am missing. And then I might be able to fabricate a part to work in my condenser.

Actually, it's not so bad to use the condenser even without "click stops." I just leave the centering telescope in place in an eyepiece tube all the time and this allows me to check on phase alignment whenever I change objectives.

Any thoughts on this little problem? Thanks in advance for your help and/or comments.

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#2 Post by billbillt » Thu Jun 22, 2017 5:00 pm

Hi Bill P.,

I don't have any phase stuff, so as usual I can't help in that area.. I am glad you are getting back to the microscope!..

Best,
BillT

apochronaut
Posts: 6272
Joined: Fri May 15, 2015 12:15 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#3 Post by apochronaut » Thu Jun 22, 2017 6:37 pm

very peculiar that the 10x and 20x annuli are the same. Are they marked with the magnification? There should be a considerable difference in size, unless someone has diy'ed the condenser in order to use objectives from a different designer.

User avatar
lorez
Posts: 735
Joined: Wed Dec 17, 2014 1:48 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#4 Post by lorez » Thu Jun 22, 2017 9:07 pm

Although unusual, it is possible to have the same annuli working for two different objectives. Swift, from the Japanese mfg. sources, had a phase set where the phase mask was the same for the 10X and 40X objectives. I cannot explain the physics, but the system works well enough to be used successfully in professional applications such as veterinary medicine and water treatment operations. The resolution of the objectives was not good enough to meet the asbestos standards. I have seen other systems with similar features, but am at a loss to name them.

lorez

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#5 Post by 75RR » Thu Jun 22, 2017 10:21 pm

Not sure how the Amscope Phase Contrast works but the Zeiss 160 tube system has just 3 annuli that cover all their Phase objectives:
Ph1: 10x
Ph2: 16x, 25x and 40x (low NA);
Ph3: 40x (high NA), 63x and 100x.

Getting back to the OP's question, I seem to recall (if memory serves me) there was a forum member that worked at Amscope doing repairs.
That might be just the person to help out on this. Can anyone can remember his avatar?
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#6 Post by billporter1456 » Fri Jun 23, 2017 2:20 am

apochronaut wrote:very peculiar that the 10x and 20x annuli are the same. Are they marked with the magnification? There should be a considerable difference in size, unless someone has diy'ed the condenser in order to use objectives from a different designer.
Currently, on the Amscope Website, they describe their phase contrast kit as including, "Four phase contrast Plan objectives, 10x, 20x, 40x and 100x." On the same page, the kit is described as, "Objective: Plan 4X/0.10, PH 10X/0.25, PH 40X/0.65, & PH OIL 100X/1.25." I have seen descriptions of this kit that describes one of the phase positions as "10/20." I have found a 20X objective very useful for observing pond water creatures and that's one reason I took a chance on this item.

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#7 Post by 75RR » Fri Jun 23, 2017 10:25 am

Removing the little silver screw on the side of the turret, I can see that there must have been a tiny part of some sort that "clicks" into one of the five small slits in the plate that holds the annuli. If someone who has this condenser is willing to remove the bottom plate of the device and maybe unscrew the little silver screw, perhaps they can see the part(s) I am missing. And then I might be able to fabricate a part to work in my condenser.
Could you post a photo of the area that is missing the 'part' ?
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#8 Post by billporter1456 » Fri Jun 23, 2017 1:23 pm

75RR wrote:
Removing the little silver screw on the side of the turret, I can see that there must have been a tiny part of some sort that "clicks" into one of the five small slits in the plate that holds the annuli. If someone who has this condenser is willing to remove the bottom plate of the device and maybe unscrew the little silver screw, perhaps they can see the part(s) I am missing. And then I might be able to fabricate a part to work in my condenser.
Could you post a photo of the area that is missing the 'part' ?
I can try to photograph my condenser later this morning, but here's an image I snatched from the Amscope site that shows the silver screw on the side of the condenser (just above the number 40 in the photo). When removed, one can see a very small hole in the bottom of the screw. Maybe this is enough to show what I am talking about?

Image

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#9 Post by 75RR » Fri Jun 23, 2017 1:52 pm

I mentioned it because the Zeiss Phase circular condensers use a ball bearing on a spring to position the ports.
It is a simple yet effective method and I thought Amscope might use a similar approach.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#10 Post by billbillt » Fri Jun 23, 2017 2:14 pm

Hi Bill P.,

Quoting 75RR,
"I mentioned it because the Zeiss Phase circular condensers use a ball bearing on a spring to position the ports.
It is a simple yet effective method and I thought Amscope might use a similar method."

My old engineer's eye tells me this is the method used here.. You need to find a ball bearing made preferably out of brass or nylon or some material that is softer than the material that it will bear against.. Maybe you can take the assembly to a hardware store and find parts to fit it.. A compression spring behind the ball should not be too difficult to find.. You will have to adjust the pressure by trial and error.. I feel this will get you working again..

BillT

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#11 Post by billporter1456 » Fri Jun 23, 2017 2:29 pm

75RR wrote:I mentioned it because the Zeiss Phase circular condensers use a ball bearing on a spring to position the ports.
It is a simple yet effective method and I thought Amscope might use a similar approach.
Here are a couple of pics of the little screw. It's about 12 mm long. The hole at the end is about 2 mm in diameter and about 7 mm deep. I can see that a tiny spring could be place in the hole and, I guess, something like a ball bearing could be at the end of the spring.

Image

Image

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#12 Post by billporter1456 » Fri Jun 23, 2017 2:32 pm

billbillt wrote:Hi Bill P.,

Quoting 75RR,
"I mentioned it because the Zeiss Phase circular condensers use a ball bearing on a spring to position the ports.
It is a simple yet effective method and I thought Amscope might use a similar method."

My old engineer's eye tells me this is the method used here.. You need to find a ball bearing made preferably out of brass or nylon or some material that is softer than the material that it will bear against.. Maybe you can take the assembly to a hardware store and find parts to fit it.. A compression spring behind the ball should not be too difficult to find.. You will have to adjust the pressure by trial and error.. I feel this will get you working again..

BillT
I think you are right, BillT, but I can't imagine where I'm going to find the right kind/size ball and the right size/compression spring. I'm thinking Amscope probably has some laying around, but since I bought the condenser used and not from them directly, I doubt they will be that helpful.

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#13 Post by billporter1456 » Fri Jun 23, 2017 2:45 pm

I just sent Amscope an email about the problem and included a link to this thread. I'll be interested in how they reply.

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#14 Post by billbillt » Fri Jun 23, 2017 5:59 pm

billporter1456 wrote:I just sent Amscope an email about the problem and included a link to this thread. I'll be interested in how they reply.
A wise move...

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#15 Post by billporter1456 » Fri Jun 23, 2017 7:19 pm

apochronaut wrote:very peculiar that the 10x and 20x annuli are the same. Are they marked with the magnification? There should be a considerable difference in size, unless someone has diy'ed the condenser in order to use objectives from a different designer.
I finally tracked down some evidence that Amscope 10X and 20X phase contrast objectives use the same size annulus. This is a quote from a description of a phase contrast kit that uses a slider to switch among brightfield, darkfield, and two phase settings: "Phase contrast kit: - NA1.25 condenser with iris diaphragm and filter holder - 37mm mounting size in diameter - Sliding switch - Four positions: darkfield (DF), brightfield (BF), PH10/20, PH40."

By the way, Amscope doesn't sell the 20X phase contrast objective separately and the current kits don't include it either. The current kits include 4X, PH10X, PH40X, and PH100X (oil) objectives. I find a 20X objective to be the most useful magnification for most of the pond water critters than I watch.

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#16 Post by billporter1456 » Fri Jun 23, 2017 10:13 pm

billbillt wrote:
billporter1456 wrote:I just sent Amscope an email about the problem and included a link to this thread. I'll be interested in how they reply.
A wise move...
I don't think I'm going to get anything useful from them. Here's their response: "Please contact us through the eBay portal as we are prohibited from discussing eBay purchases outside of their messaging system due to their policies. You would want to login and go to your purchase history. Under your order with us, you can click on contact seller and send a message with the details you are describing."

The problem is that I didn't buy it from THEM on eBay. Oh well, I wasn't expecting much from them anyway.

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#17 Post by billbillt » Fri Jun 23, 2017 10:55 pm

Here might be the spring..

http://www.ebay.com/itm/0-3mmx2mmx40mm- ... 1438.l2649

Do you have any dial or digital calipers that you can measure your part with?... That would help..

BillT

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#18 Post by billporter1456 » Fri Jun 23, 2017 11:37 pm

billbillt wrote:Here might be the spring..

http://www.ebay.com/itm/0-3mmx2mmx40mm- ... 1438.l2649

Do you have any dial or digital calipers that you can measure your part with?... That would help..

BillT
Yep, that might work. I found the same springs from the same seller with fewer pieces, so even cheaper. By "measure your part," I guess you mean measure the screw? I can't measure the spring because that's the part that's missing. The screw is about 12 mm long, the old about 2 mm and the depth of the hole about 7 mm.

By the way, I went ahead and order 10 of those springs for about $5. Now I guess I can look around for a ball of some sort. Thanks, Bill!

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#19 Post by billbillt » Sat Jun 24, 2017 12:11 am

It doesn't necessarily have to be a "ball"... Sometimes a piece of a brass welding rod cut off might work.... Just as long as the material it is made of is softer than the steel of the surface it rides on..

BillT

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#20 Post by 75RR » Sat Jun 24, 2017 1:46 am

It doesn't necessarily have to be a "ball"...
If it is like the Zeiss, then it most likely will partially drop into a slot as you rotate the condenser, which will locate and hold the port in position - if that is the case a ball is the best design.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#21 Post by billporter1456 » Sat Jun 24, 2017 3:07 am

75RR wrote:
It doesn't necessarily have to be a "ball"...
If it is like the Zeiss, then it most likely will partially drop into a slot as you rotate the condenser, which will locate and hold the port in position - if that is the case a ball is the best design.
The "slots" in my condenser are small rectangular openings. I could photograph them if that would be helpful. (Not tomorrow as I am taking my wife on her first train ride.) I am guessing that a ball would work. I ordered the springs that BillT found for me, but they are coming from China and it will be a couple of weeks before they get here.

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#22 Post by 75RR » Sat Jun 24, 2017 10:00 am

... they are coming from China and it will be a couple of weeks before they get here.
Might as well keep it in the family:

http://www.ebay.com/itm/2mm-25mm-qualit ... BRryZxWtpw

No need for photos - enjoy your trip
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#23 Post by billbillt » Sat Jun 24, 2017 2:22 pm

billporter1456 wrote:
75RR wrote:
It doesn't necessarily have to be a "ball"...
If it is like the Zeiss, then it most likely will partially drop into a slot as you rotate the condenser, which will locate and hold the port in position - if that is the case a ball is the best design.
The "slots" in my condenser are small rectangular openings. I could photograph them if that would be helpful. (Not tomorrow as I am taking my wife on her first train ride.) I am guessing that a ball would work. I ordered the springs that BillT found for me, but they are coming from China and it will be a couple of weeks before they get here.
A ball or radial shape will work in that case.. There are literally dozens of ways to accomplish indexing of a mechanism.. This is just a popular method.. Every designer has his own ideas on how to do it.. Glad you will soon have this solved.. Please post updates.. I love to see how others solve problems..

BillT

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#24 Post by billbillt » Sat Jun 24, 2017 2:41 pm

75RR wrote:
... they are coming from China and it will be a couple of weeks before they get here.
Might as well keep it in the family:

http://www.ebay.com/itm/2mm-25mm-qualit ... BRryZxWtpw

No need for photos - enjoy your trip
Yes, a polymer material will work..


BillT

billbillt
Posts: 2895
Joined: Mon Nov 10, 2014 10:01 pm

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#25 Post by billbillt » Sat Jun 24, 2017 2:50 pm

I know this is OT, but everyone should have one of these around the house..

http://www.ebay.com/itm/6-150mm-Stainle ... Sw65FXrJfP

Very inexpensive and very handy...

I just bought another one from this person...

BillT

User avatar
Crater Eddie
Posts: 1858
Joined: Wed Nov 12, 2014 4:39 pm
Location: Illinois USA

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#26 Post by Crater Eddie » Sun Jun 25, 2017 4:47 am

I want to see pictures of the train.
CE
Olympus BH-2 / BHTU
LOMO BIOLAM L-2-2
LOMO POLAM L-213 / BIOLAM L-211 hybrid
LOMO Multiscope (Biolam)
Cameras: Canon T3i, Olympus E-P1 MFT, Amscope 3mp USB

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#27 Post by billporter1456 » Sun Jun 25, 2017 1:13 pm

75RR wrote:
... they are coming from China and it will be a couple of weeks before they get here.
Might as well keep it in the family:

http://www.ebay.com/itm/2mm-25mm-qualit ... BRryZxWtpw

No need for photos - enjoy your trip
Wow, total cost with shipping just $2.53! But what do I do with the 999 extra beads??? :>)

Thanks for the tip.

User avatar
75RR
Posts: 8207
Joined: Sun Oct 12, 2014 2:34 am
Location: Estepona, Spain

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#28 Post by 75RR » Sun Jun 25, 2017 9:41 pm

billporter1456 wrote:
75RR wrote:
... they are coming from China and it will be a couple of weeks before they get here.
Might as well keep it in the family:

http://www.ebay.com/itm/2mm-25mm-qualit ... BRryZxWtpw

No need for photos - enjoy your trip
Wow, total cost with shipping just $2.53! But what do I do with the 999 extra beads??? :>)

Thanks for the tip.
If you know any 'hunters' you may be able to save even that. A lead shotgun pellet should work fine.

Image
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

billporter1456
Posts: 492
Joined: Thu Oct 16, 2014 12:05 am

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#29 Post by billporter1456 » Sun Jun 25, 2017 11:55 pm

75RR wrote:
billporter1456 wrote:
75RR wrote:Might as well keep it in the family:

http://www.ebay.com/itm/2mm-25mm-qualit ... BRryZxWtpw

No need for photos - enjoy your trip
Wow, total cost with shipping just $2.53! But what do I do with the 999 extra beads??? :>)

Thanks for the tip.
If you know any 'hunters' you may be able to save even that. A lead shotgun pellet should work fine.

Image
Yes, a pellet around 2 mm should work. Unfortunately, it will be a couple of weeks before I get the springs I ordered. One of the forum members, Captain Kirk, PM'ed me to say that he has this condenser and is willing to take it apart to photo the mechanism that provides the click stops. I'm looking forward to those pics.

User avatar
Crater Eddie
Posts: 1858
Joined: Wed Nov 12, 2014 4:39 pm
Location: Illinois USA

Re: Anyone have an Amscope PCT 120 phase contrast condenser?

#30 Post by Crater Eddie » Mon Jun 26, 2017 12:14 pm

I would think that a lead pellet would deform over time and cause problems. But maybe not.
CE
Olympus BH-2 / BHTU
LOMO BIOLAM L-2-2
LOMO POLAM L-213 / BIOLAM L-211 hybrid
LOMO Multiscope (Biolam)
Cameras: Canon T3i, Olympus E-P1 MFT, Amscope 3mp USB

Post Reply