Search found 2713 matches

by zzffnn
Sat Jun 29, 2019 11:12 pm
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

Hobbyst46, They are look good to me. f/5.6 seems slightly sharper than f/1.8 without 100% crop, but difference is not significant. I think since front lens (100x NA 1.3) of your system is already deep into diffraction, you won't lose anything when stopping down from f/1.8 to f/5.6, you may actually ...
by zzffnn
Fri Jun 28, 2019 9:29 pm
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

Hobbyst46, Your M10 camera's sensor is APSC and larger than my micro 43 sensor (supposedly your camera's iso performance will be better). I suggest using iso 200, aperture priority mode (let camera meter exposure based on dot or center-weighted metering mode and determine which shutter speed to use,...
by zzffnn
Fri Jun 28, 2019 6:38 pm
Forum: My microscope
Topic: Bobs traveling microscopy kit (plancton)
Replies: 29
Views: 9568

Re: Bobs traveling microscopy kit (plancton)

Bob, Some outdoor LED headlights can be smaller (with head straps removed) and can be focused with two levels of adjustable power. There may be other battery-powered LED options, such as flat flashlights or small flat work lights, but I have not found a perfect one yet. Those headlights are usable t...
by zzffnn
Fri Jun 28, 2019 3:42 am
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

For darkfield, I also want to echo what apochronaut has said before: try to remove all air bubbles in your immersion oil, between condenser and slide especially. One single bubble near your subject can cause significant flare and contrast lost. For the COL imaging I did today, I had some bubbles ove...
by zzffnn
Thu Jun 27, 2019 10:22 pm
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

The following images were taken with a 28mm afocal lens, so diatoms herein look slightly smaller than the visual view at 900x. This diatom is not flat against cover slip (even though it came from a inverted cure) and is therefore difficult to resolve: not flat difficult.JPG Here you can see an oval ...
by zzffnn
Thu Jun 27, 2019 10:04 pm
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

COL 90x NA 1.3, LOMO oil apo non-plan, back focal plane (due to light spill, the light ring appears about 1.5x-2x wider that it actually was): bfp.jpg All photos presented herein are single (non-stacked) captures. Only one image was digitally enhanced (all others came straight from camera, except fo...
by zzffnn
Thu Jun 27, 2019 8:41 pm
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

Hobbyst46, Most likely, the diatoms that you used as resolution targets were too difficult to resolve. I viewed your images at 100% and think they may be good enough for those mounts. Even from inverted cure (diatoms sticking to cover slips), you still cannot guarantee perfectly flat mount. Many dia...
by zzffnn
Thu Jun 27, 2019 7:04 pm
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

You have to completely open up field diaphragm.

Also some diatoms (such as those very long ones in your photos) never sit flat on cover slips and are naturally low in contrast. Do not use them as resolution targets.
by zzffnn
Thu Jun 27, 2019 5:04 pm
Forum: Microscopes and optics
Topic: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)
Replies: 20
Views: 2548

Re: Performance of high NA objectives with Zeiss Utracondenser (cardiodid)

Hobbyst46, I will try to get you some photos from my COL in a few days. Was visual view of COL more contrasty than those photos? If visual view is significantly better: play with camera's metering and exposure compensation. Use single dot metering and put that dot on your exact diatom. Then dial dow...
by zzffnn
Sun Jun 23, 2019 9:11 pm
Forum: Microscopes and optics
Topic: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?
Replies: 35
Views: 5118

Re: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?

Congratulations, Hobbyst46, on getting NA 1.0 darkfield! You said you 100x NA 1.3 phase objective could not produce good COL with ultracondenser; Can you post a photo of the objective back focal plane (remove eyepiece, and position camera on empty eye tube)? It should look more like fig. 10 of this ...
by zzffnn
Sat Jun 22, 2019 11:29 pm
Forum: For forum members who want to buy and sell equipment
Topic: Interested in a DIC microscope.
Replies: 11
Views: 3348

Re: Interested in a DIC microscope.

^ That sounds like a very good price. Where is my lottery ticket when I need it :evil:
by zzffnn
Sat Jun 22, 2019 10:35 pm
Forum: Microscopes and optics
Topic: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?
Replies: 35
Views: 5118

Re: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?

...My 40w LED barely provide enough light at that magnification/NA. NA 1.1 actually helped by gathering more light Hi zzffnn, this is a citation from your interesting post about darkfield in Photomacrography.net, back in 2016. Now that raises a question. You have been using a 40W LED on (which ?) Z...
by zzffnn
Sat Jun 22, 2019 7:08 am
Forum: Microscopes and optics
Topic: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?
Replies: 35
Views: 5118

Re: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?

Bob, Your Zeiss pancratic condenser is not a typical darkfield condenser. Its zoom mechanism is similar to my Leitz Heine, so it could have a higher NA range, like my Leitz Heine. The 3rd zoom condenser that I know of is the rare Reichert Polyphos condenser (supplied with some Zetopans). Remember th...
by zzffnn
Sat Jun 22, 2019 3:22 am
Forum: Microscopes and optics
Topic: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?
Replies: 35
Views: 5118

Re: Zeiss Cardiodid condenser fails with high NAs - peeling paint ?

Hobbyst46, I don't think you should expect good darkfield at NA 1.25, which is theoretically impossible for a 1.2/1.4 darkfield condenser (NA 1.2-1.4 is where you will have the illumination ring). You may see good to decent darkfield at objective NA 0.8, depending on subject/background and alignment...
by zzffnn
Fri Jun 21, 2019 2:47 am
Forum: For forum members who want to buy and sell equipment
Topic: FOR SALE - Leitz Orthoplan ++ extras
Replies: 13
Views: 2089

Re: FOR SALE - Leitz Orthoplan ++ extras

John B, Wanting to try another scope is certainly a good reason, however I don't think BX40 will provide much better image quality. Your botanical slides are very forgiving on objectives, as they are contrasty (once stained) and immobile. Maybe try Leitz's plan Apo 170tl objectives, if you don't hav...
by zzffnn
Mon Jun 17, 2019 1:04 am
Forum: Miscellaneous
Topic: Portable microscope
Replies: 47
Views: 12168

Re: Portable microscope

Beautiful! I remember it now, Bob. You were calling it "Biolamini" instead of "Biolam Mini" and it is in the FM-31 thread. No wonder why my search returned nothing. Your focus drive mechanism looks difficult for me to replicate though. I am sure you have put lots of thoughts in its connections and j...
by zzffnn
Sun Jun 16, 2019 3:18 pm
Forum: Miscellaneous
Topic: Portable microscope
Replies: 47
Views: 12168

Re: Portable microscope

Bob, it looks almost exactly like the original: https://www.amazon.com/My-First-Lab-Duo-Scope-Microscope/dp/B000NOU54O I simply removed the factory condenser diaphragms, enlarged the condenser opening and added on an old Nikon Abbe condenser with two-part epoxy clay. And its eyetube can be unscrewed...
by zzffnn
Sun Jun 16, 2019 5:00 am
Forum: Miscellaneous
Topic: Portable microscope
Replies: 47
Views: 12168

Re: Portable microscope

In that case, the Oly scope is too heavy for my use. Bob, I think your modified LOMO scope would beat that Oly easily too. I have added a condenser to a educational toy "My First Lab Duo" scope. It weight 900 grams with LED light, batteries and condenser. Its eyepiece provides decent field size and ...
by zzffnn
Sat Jun 15, 2019 5:41 pm
Forum: Miscellaneous
Topic: Portable microscope
Replies: 47
Views: 12168

Re: Portable microscope

Thank you, Bob. How heavy is your Olympus MIC scope? Would you please quantify how small the viewing field is (compared to the standard 18mm field width), is it closer to 20% smaller or 30% smaller? I assume its eye tube cannot take RMS standard eyepiece? I wear strong eyeglasses, so field width sma...
by zzffnn
Sat Jun 15, 2019 4:23 pm
Forum: Miscellaneous
Topic: Portable microscope
Replies: 47
Views: 12168

Re: Portable microscope

So the objectives do not have RMS thread? DIY adaptation may be possible, if thread diameters are not too far apart. And there is no condenser (but adding a DIY one there shouldn't be difficult). Everything else looks great for me. Too bad shipping cost will kill the deal, otherwise I would bid. I d...
by zzffnn
Sat Jun 15, 2019 5:50 am
Forum: Microscopes and optics
Topic: Focusing by Changing the Tube Length
Replies: 6
Views: 1082

Re: Focusing by Changing the Tube Length

Sorry for my typo, I meant "every few milimeters count".
by zzffnn
Fri Jun 14, 2019 11:44 pm
Forum: Microscopes and optics
Topic: Focusing by Changing the Tube Length
Replies: 6
Views: 1082

Re: Focusing by Changing the Tube Length

Focusing by changing tube length is not ideal at higher NA. Once you go over NA 0.6 or so, very few milometers count.

Also you probably cannot do focus stacking easily, when your magnification changes during focus.
by zzffnn
Thu Jun 13, 2019 7:53 am
Forum: Illumination Techniques
Topic: PZO DIC with MPI-3 and KPI-2
Replies: 14
Views: 4809

Re: PZO DIC with MPI-3 and KPI-2

An eBay seller from Poland told me the same thing: MPI-5 is supposed to be better. I did not ask why and did not buy it though.
by zzffnn
Tue Jun 11, 2019 3:01 pm
Forum: Illumination Techniques
Topic: dIY DIC
Replies: 38
Views: 10179

Re: dIY DIC

Thank you very much @PeteM. You made a great point, which would save me (and likely other DIY microscopists) quite a bit of money! Let me know how I can return your favor or buy you some (virtual) beer. The Nikon epi attachment that I have adds 50mm to optical tube length and does not have a pair of...
by zzffnn
Sun Jun 09, 2019 3:45 pm
Forum: Illumination Techniques
Topic: dIY DIC
Replies: 38
Views: 10179

Re: dIY DIC

Bob, Forum member Saul at Photomacrography.net already 3D- printed filters (w/ holder inserted) for Olympus BH(2?) and Nikon Labophot/Optiphot and is probably working on others: http://www.photomacrography.net/forum/viewtopic.php?p=248468&highlight=#248468 DIY oblique should not be too difficult, ev...
by zzffnn
Sun Jun 09, 2019 3:15 pm
Forum: Illumination Techniques
Topic: dIY DIC
Replies: 38
Views: 10179

Re: dIY DIC

Wes, Sorry to be so blunt. Your rotifer image came out great, so I agree that mismatched 16/0.35 slider worked well at 10/0.32. Have you tested your 63x slider + 40x Apo on a small rotifer or its body part though? I think paramecium is a comparatively easier subject for DIC, as it would look quite g...
by zzffnn
Sun Jun 09, 2019 4:21 am
Forum: Illumination Techniques
Topic: dIY DIC
Replies: 38
Views: 10179

Re: dIY DIC

Here is the gradient oblique template that I made, which may be easier to print than the original: http://www.photomacrography.net/forum/v ... ght#173389
by zzffnn
Sun Jun 09, 2019 1:29 am
Forum: Pictures and Videos
Topic: Shell picking from Red Sea sand
Replies: 45
Views: 8492

Re: Shell picking from Red Sea sand

Very nice work, Hobbyst46. Sorry, I did not mean your light in 1st attempt was harsh (and I apologize, as my previous post was too blunt). I do prefer your image #29 though. Sometimes hot spots are trade-offs that we have to accept, for convenience, working distance or speed. And indeed, if one remo...
by zzffnn
Sat Jun 08, 2019 11:01 pm
Forum: Illumination Techniques
Topic: dIY DIC
Replies: 38
Views: 10179

Re: dIY DIC

DIY oblique gets difficult over 40x NA 0.65 and does not produce the same contrast DIC produces. My own (years of) test results showed that DIY oblique can provide decent visual 3D effects at high power, but such effects cannot be easily captured with camera. So for me, if I were to pursue DIY DIC l...
by zzffnn
Wed May 29, 2019 12:50 am
Forum: Pictures and Videos
Topic: Shell picking from Red Sea sand
Replies: 45
Views: 8492

Re: Shell picking from Red Sea sand

Very nice images, Hobbyst46! May I suggest use an objective hood (wrapped tightly around objective lens) made of Vellum paper for better difdusion? Even think office paper will work better than not having any diffusion. In you photo #19, I can see two hot spots, perpendicular to them, I can kind of ...