Search found 1160 matches

by Ichthyophthirius
Thu Apr 15, 2021 10:09 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Darkfield Microscopy... is it that easy?
Replies: 4
Views: 1392

Re: Darkfield Microscopy... is it that easy?

Is it as easy as sorting your illumination and sticking a filter before the condenser? Yes, for anything up to the 40:1 objective. The 10 - 40 range is probably the most rewarding with a simple condenser stop. You can also do oblique illumination in that range. A bright LED illumination is an advan...
by Ichthyophthirius
Wed Apr 14, 2021 1:32 am
Forum: Equipment Discussions
Topic: Interesting Canon 100mm - 1.4x Possibilty
Replies: 9
Views: 8165

Re: Interesting Canon 100mm - 1.4x Possibilty

Canon has just announced that it really is a spherical aberration control ring. https://www.canon.co.uk/lenses/canon-rf-100mm-f2-8l-macro-is-usm/ The announcement is about the bokeh control. What I'm particularly curious about is whether the over-correction range is enough to image through thick gla...
by Ichthyophthirius
Thu Apr 08, 2021 4:33 pm
Forum: Equipment Discussions
Topic: Optiphot 66 curiosities
Replies: 8
Views: 2103

Re: Optiphot 66 curiosities

(1) what purpose does the model T head bottom lens serve? Hi, I'm not 100 % sure which lens you mean; is it the one at the bottom of he camera port? As far as I can tell, the trinocular type-T has a negative lens at the base of the trinocular and a positive lens at the bottom of the camera port: ht...
by Ichthyophthirius
Mon Apr 05, 2021 10:11 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Shutter second curtain shock moving water mount subjects when using OIL objectives
Replies: 4
Views: 1090

Re: Shutter second curtain shock moving water mount subjects when using OIL objectives

Hi,

You mean the vibrations after the shot is taken distub the subject? Yes, working with oil immersion objectives can be tough.

You can uncouple your camera mechanically by using a copy stand:
http://www.photomacrography1.net/images ... 3small.jpg
https://krebsmicro.com/microsetup2/0045.jpg
by Ichthyophthirius
Sun Apr 04, 2021 6:39 am
Forum: Equipment Discussions
Topic: Mejiro Genossen Fl0530 4.0/110mm 0.5x-3x macro lens On eBay
Replies: 29
Views: 3500

Re: Mejiro Genossen Fl0530 4.0/110mm 0.5x-3x macro lens On eBay

Quick question: What does the "Genossen" mean in the company name? It means "comrade" in German (as in, member of a co-operative) but I can't find a Japanese meaning. Is it a locality? Otherwise that's a very odd choice of name for a Japanese company :D
by Ichthyophthirius
Fri Apr 02, 2021 8:14 am
Forum: Equipment Discussions
Topic: Fedex and the Lost Inspec.x L Float Lens Saga
Replies: 15
Views: 1895

Re: Fedex and the Lost Inspec.x L Float Lens Saga

Meanwhile Fedex profits soar but customer service plummets. Is this a new Fedex? FedEx profit soars with pandemic-fueled delivery demand By Reuters Staff .....Revenue for the quarter ended Feb. 28 grew 23% to $21.5 billion. ......FedEx profits nearly triple amid online shopping spike in its third q...
by Ichthyophthirius
Thu Apr 01, 2021 11:21 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Very bad image quality when using polarizers on a microscope, why?
Replies: 4
Views: 1444

Re: Very bad image quality when using polarizers on a microscope, why?

Hi, Ideally, use a non-anisotropic (i.e. isotropic) object for a resolution and contrast test, like a stage micrometer. If you use crystals, there are additional pol-optical effects that make the images difficult to analyse. The analyser is critical for pol microscopy. A poor quality or damaged filt...
by Ichthyophthirius
Mon Mar 29, 2021 4:39 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?
Replies: 24
Views: 5034

Re: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?

So going back to relay lenses, would it be possible to use something like a 2.5x photoeyepiece at another magnification by changing the distance ratios objective>eyepiece>camera while keeping the system parfocal? Hi, I still think it's possible to use the NFK2.5x together with a focal reducer. Redu...
by Ichthyophthirius
Fri Mar 26, 2021 4:57 pm
Forum: Equipment Discussions
Topic: Raynox 150 or Marumi +5
Replies: 10
Views: 2007

Re: Raynox 150 or Marumi +5

Optically, you really can't go wrong with a 90 mm Tamron or 105 mm Sigma macro lens.

Longer focal length allows a longer working distance. You really want to get some respectful distance between yourself and the Everglades wildlife :D
by Ichthyophthirius
Fri Mar 26, 2021 3:49 pm
Forum: Equipment Discussions
Topic: Apo-Rodagon f2.8-50mm - Can it be opened?
Replies: 6
Views: 1453

Re: Apo-Rodagon f2.8-50mm - Can it be opened?

Hi Ray, Hi Robert,

Thank you! It worked. Beware of the shims :D
by Ichthyophthirius
Fri Mar 26, 2021 1:03 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?
Replies: 24
Views: 5034

Re: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?

Do you know of any visualizations of what the light path looks like when you raise the eyepiece this way? Yes, this graphic shows common camera adaptations: https://www.mikroskopie-forum.de/pictures004/149894_43766975.jpg I: Visual lightpath (visual eyepiece and human eye) II: Afocal (eyepiece and ...
by Ichthyophthirius
Fri Mar 26, 2021 12:17 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?
Replies: 24
Views: 5034

Re: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?

Ah, I see. So you're maintaining the correct position of the intermediate image (at 150 mm) and only the distance between intermediate image and eyepiece changes (from 10 mm to 15 mm). I described that incorrectly above.
by Ichthyophthirius
Fri Mar 26, 2021 10:39 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?
Replies: 24
Views: 5034

Re: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?

But there will be some spherical aberration introduced by the eyepiece being used far away from its design point. Yeah, that's what I was getting at. For eyepiece projection, a 10x eyepiece has to be lifted by 5 mm (for k = 125 mm camera length); a tube length increase of 5 mm would just about be a...
by Ichthyophthirius
Fri Mar 26, 2021 8:37 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?
Replies: 24
Views: 5034

Re: Eyepieces, photoeyepieces and Teleconverters; what are the similarities and differences? Should we care?

- I also tried using a Nikon SC 10x eyepiece as a photo eyepiece (10x/18), this so far is working pretty well. First I did set the eyepiece parfocal and then placed a extension tube so that there was not vigneting. I realized later parfocality was lost buy playing with placement of both camera and ...
by Ichthyophthirius
Fri Mar 26, 2021 8:15 am
Forum: Equipment Discussions
Topic: Apo-Rodagon f2.8-50mm - Can it be opened?
Replies: 6
Views: 1453

Apo-Rodagon f2.8-50mm - Can it be opened?

Hi, I have an Apo-Rodagon f2.8-50 mm #75.050.01 enlarger lens in the "mid style" barrel like this one, in which the aperture clicks are engaged by pushing the barrel in and out: http://www.photocornucopia.com/archive/69/Rodenstock%20APO%2050%20and%2090.pdf https://www.mrcad.co.uk/product/rodenstock-...