Search found 429 matches

by viktor j nilsson
Mon Jun 14, 2021 7:06 am
Forum: Beginner's corner
Topic: Polychromatic polarization
Replies: 21
Views: 593

Re: Polychromatic polarization

Patta, I have enjoyed this very much. Fascinating stuff. The fact that they sell a custom-built product definately makes a lot of sense, and explains why the papers were rather vague with regards to some critical aspects. Thank you so much for clarifying much of it. In one of the papers you linked t...
by viktor j nilsson
Sun Jun 13, 2021 8:35 pm
Forum: Microscopes and optics
Topic: Making my own Leitz Heine oil cap - questions about adhesives and optics
Replies: 29
Views: 9384

Re: Making my own Leitz Heine oil cap - questions about adhesives and optics

...First, I need to clean up a little silicone that ended up on the half ball lens. Second, I think I will add a second layer of defence around the edge of the lens to protect against immersion oil. Maybe nail varnish?... I do not know if that question is still open, but may I note that nail varnis...
by viktor j nilsson
Sun Jun 13, 2021 8:03 pm
Forum: Microscopes and optics
Topic: Making my own Leitz Heine oil cap - questions about adhesives and optics
Replies: 29
Views: 9384

Re: Making my own Leitz Heine oil cap - questions about adhesives and optics

Oh, and I might have found a second Leitz Heine with the 39.5mm condenser sleeve AND oil cap for a very affordable price. So in the end I might not need this one at all. If I get it, I will of course try them out against each other to see how the DIY version works out! After a long covid-related de...
by viktor j nilsson
Sun Jun 13, 2021 7:50 pm
Forum: Microscopes and optics
Topic: OFR (OPTICS FOR RESEARCH)
Replies: 7
Views: 200

Re: OFR (OPTICS FOR RESEARCH)

If you are curious, Jonathan Crowther has done amazing work converting his Olympus BH info a UV microscope. I'll link to one of his blog posts below, there are several other interesting ones if you search his blog.

https://jmcscientificconsulting.com/uv- ... -it-works/
by viktor j nilsson
Thu Jun 10, 2021 4:47 pm
Forum: Beginner's corner
Topic: Viewing Bacteria With Bright-field Microscopy
Replies: 25
Views: 468

Re: Viewing Bacteria With Bright-field Microscopy

I see. I have assembled most of the parts I need to build a structured illumination microscope using a 10lines/mm Ronchi grating as a mask, and some stepper motors and a raspberry pi to do the rotation and lateral shift. It should be able to achieve sub-diffraction resolution and good optical sectio...
by viktor j nilsson
Thu Jun 10, 2021 2:57 pm
Forum: Beginner's corner
Topic: Viewing Bacteria With Bright-field Microscopy
Replies: 25
Views: 468

Re: Viewing Bacteria With Bright-field Microscopy

That's true but light microscopy still has severe limitations in viewing small structures but increasing capability in viewing process. We still haven't broken the .2 micron barrier although there are rumours of various advances. Pre-magnifying with nano lenses, lots of digital modifications. Can y...
by viktor j nilsson
Sun Jun 06, 2021 10:02 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

Glad you found it useful! You are clearly doing good progress. Looking forward to seeing further updates. One thing that I started thinking about is if the Sanderson prisms are stable over time, or if the shearing characteristics will change over time due to fatigue. Have you read anything about this?
by viktor j nilsson
Fri Jun 04, 2021 11:29 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

I actually think you can get pretty close to 65urad simply by looking at the interference bands between crossed polarizers (as in figure 3 in Rathi et al). High and low-magnification prisms are easy to tell apart, as in this figure from Olympus' DIC primer: https://static3.olympus-lifescience.com/da...
by viktor j nilsson
Fri Jun 04, 2021 10:15 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

I haven't read up on the Sanderson prism theory, and skimmed parts of this thread, so I may be missing something obvious here, but do you really need to measure and replicate the exact same divergence angles as those used in the paper? In regular DIC, the following criteria needs to be met to achiev...
by viktor j nilsson
Thu Jun 03, 2021 12:06 pm
Forum: Microscopes and optics
Topic: LED/Flash illuminator 2.0 for Olympus Vanox AH
Replies: 1
Views: 86

LED/Flash illuminator 2.0 for Olympus Vanox AH

Finally had time and energy to pull out the soldering iron and finish this project. Flash capacitors are scary, and I always make mistakes when I'm tired so it took me a while to find a good time. https://i.imgur.com/IMKTWF5.jpg https://i.imgur.com/R1vHDQv.jpg https://i.imgur.com/4li4PMC.jpg https:/...
by viktor j nilsson
Thu Jun 03, 2021 5:56 am
Forum: Microscopes and optics
Topic: Vanox dovetail
Replies: 13
Views: 287

Re: Vanox dovetail

Yes, and as shown in the thread I linked, the Olympus circular dovetail is 42mm, so it's very close. Could work. People have mostly had trouble getting PZO DIC units to work on Olympus microscopes, the reverse should be easier. The Vanox head might work. But I don't know the tube length of the vano...
by viktor j nilsson
Wed Jun 02, 2021 2:47 pm
Forum: Microscopes and optics
Topic: Vanox dovetail
Replies: 13
Views: 287

Re: Vanox dovetail

Yes, and as shown in the thread I linked, the Olympus circular dovetail is 42mm, so it's very close. Could work. People have mostly had trouble getting PZO DIC units to work on Olympus microscopes, the reverse should be easier. The Vanox head might work. But I don't know the tube length of the vanox...
by viktor j nilsson
Wed Jun 02, 2021 11:20 am
Forum: Microscopes and optics
Topic: Vanox dovetail
Replies: 13
Views: 287

Re: Vanox dovetail

by viktor j nilsson
Wed Jun 02, 2021 11:16 am
Forum: Microscopes and optics
Topic: Vanox dovetail
Replies: 13
Views: 287

Re: Vanox dovetail

Oh, you meant the circular dovetail that connects the head and the nosepiece. Sorry, my measurements are for the linear dovetail that connects the head to the frame. That actually makes more sense since you asked for the diameter. But I didn't consider that possibility, since that dovetail dimension...
by viktor j nilsson
Wed Jun 02, 2021 5:59 am
Forum: Microscopes and optics
Topic: Vanox dovetail
Replies: 13
Views: 287

Re: Vanox dovetail

Here are the dimensions of the Vanox AH head dovetail. Let me know if there's any other measurement you need. https://i.imgur.com/SRpJURP.jpg Edit: I misunderstood Apo's question. To clarify, the measurements above are for the linear dovetail at the rear side of the head, as shown here: https://i.im...
by viktor j nilsson
Wed Jun 02, 2021 5:51 am
Forum: Microscopes and optics
Topic: Vanox dovetail
Replies: 13
Views: 287

Re: Vanox dovetail

I guess you are talking about the older analog Vanox AH? Not the electronic monster, AH-2. I can measure my Vanox AH later today.
by viktor j nilsson
Tue Jun 01, 2021 12:10 pm
Forum: My microscope
Topic: Tungsten needle for diatom manipulation.
Replies: 15
Views: 351

Re: Tungsten needle for diatom manipulation.

It's a very cool technique. There were a couple threads on the on photomacrography forum a while ago, with some very nice images:

https://www.photomacrography.net/forum/ ... hp?t=41452

https://www.photomacrography.net/forum/ ... p?p=260845
by viktor j nilsson
Sun May 30, 2021 7:30 am
Forum: Microscopes and optics
Topic: 100x Concerns
Replies: 29
Views: 1106

Re: 100x Concerns

I use a small syringe with a 21G needle (0.8mm x 40mm) to apply immersion oil. I find that I can have much better control over placement and quantity this way.
by viktor j nilsson
Mon May 24, 2021 8:20 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

Yes, sorry. This question was always off topic here. I'll leave it at that. Go ahead Louise, looking forward to seeing more from this interesting project!
by viktor j nilsson
Mon May 24, 2021 8:16 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

Here's another one using a Olympus UMPlanFI 50x/0,80 on a Canon EF 70-200L zoom lens as a tube lens:

https://www.photomacrography.net/forum/ ... 9&p=267397
by viktor j nilsson
Mon May 24, 2021 8:12 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

I don't know of any equally carefully controlled comparisons with an Olympus UIS2 objective, but I've seen plenty of very clean images taken with Olympus objectives and a Raynox DCR-150 as a tube lens. Check: clean images with 40* UIS2 objectives? I’m really curious to learn more, Please supply a l...
by viktor j nilsson
Mon May 24, 2021 6:50 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

Sure, stopping down will close off whatever peripheral aberrations that it does in any specific situation and the tube lens is usually thin and of low curvature and the Raynox DCR-150 is a very wide lens so benefits from it's original aperture and is used reversed, so their negative contributions m...
by viktor j nilsson
Mon May 24, 2021 5:07 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

Louise, the point I'm making is - for optimal optical quality it may be wise to use the optical components in a matched system, usually the same “design period” of a single supplier. Mix and match is not a sound approach in my (limited) experience, YMMV though. Usually, yes. But lots of folks over ...
by viktor j nilsson
Sun May 23, 2021 9:45 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

That said, it would be good to see a clean brightfield image taken without the prisms to see which of the aberrations in the image are caused by the prisms, and which ones are caused by the rest of your setup. And it really helps to be able to view the back focal plane when you are setting up a DIY ...
by viktor j nilsson
Sun May 23, 2021 9:28 pm
Forum: Illumination Techniques
Topic: DIC Question
Replies: 107
Views: 3330

Re: DIC Question

Louise, the point I'm making is - for optimal optical quality it may be wise to use the optical components in a matched system, usually the same “design period” of a single supplier. Mix and match is not a sound approach in my (limited) experience, YMMV though. Usually, yes. But lots of folks over ...
by viktor j nilsson
Sat May 01, 2021 7:11 pm
Forum: My microscope
Topic: Olympus FHT
Replies: 26
Views: 4588

Re: Olympus FHT

The most annoying thing is that it seems hard to find decent eyepieces. Most of them in Ebay must have been in very hard use by non-professional students and have lots of scratches resulted from cleaning. However, I have now rather decent ones. This is a good point. And the olympus short-barrrel ob...
by viktor j nilsson
Thu Apr 22, 2021 4:13 pm
Forum: For forum members who want to buy and sell equipment
Topic: sold: Zeiss Planapo 63/1,4 for sale
Replies: 1
Views: 266

Re: Zeiss Planapo 63/1,4 for sale

I'd love to buy it for a friend. Has it been spoken for? If not, I'll buy it!
by viktor j nilsson
Mon Apr 12, 2021 10:27 pm
Forum: Illumination Techniques
Topic: can Phase contrast kit work WITHOUT Köhler ???
Replies: 17
Views: 938

Re: can Phase contrast kit work WITHOUT Köhler ???

BM = bright medium, aka negative phase contrast.
by viktor j nilsson
Mon Apr 12, 2021 5:53 pm
Forum: Beginner's corner
Topic: Decision: Amscope T400A-30W Any thoughts?
Replies: 21
Views: 869

Re: Decision: Amscope T400A-30W Any thoughts?

Are Amscope microscopes ever NOT on sale? I sure have never seen them being sold at the "list price". Here in Sweden, that type of false marketing is illegal. But clearly not in the US. Is the current "sale" price really any lower than usual? I don't keep tabs.
by viktor j nilsson
Mon Apr 12, 2021 6:31 am
Forum: Beginner's corner
Topic: Very dirty Nikon microscope, what to do?
Replies: 13
Views: 895

Re: Very dirty Nikon microscope, what to do?

Fixing up a Nikon S is definitely something you can do yourself if you have some basic mechanical experience (and it seems you do). Fixing your own microscope is a great way to learn about and become familiar with your equipment. With that said, I wonder if it's worth it. It sounds as if your micros...