Search found 1297 matches

by enricosavazzi
Wed Oct 14, 2020 9:20 am
Forum: Equipment Discussions
Topic: Can I push the resolution of a 1:1 macro lens?
Replies: 23
Views: 1125

Re: Can I push the resolution of a 1:1 macro lens?

Lou Jost wrote:
Wed Oct 14, 2020 6:51 am
I added a short discussion and a couple of links about the other methods.

Thanks, that will be helpful to many.

I could not find the new additions, am I missing something?
Perhaps there is a server cache or something else that does not update immediately.
Clip0002a.jpg
by enricosavazzi
Wed Oct 14, 2020 6:32 am
Forum: Equipment Discussions
Topic: Can I push the resolution of a 1:1 macro lens?
Replies: 23
Views: 1125

Re: Can I push the resolution of a 1:1 macro lens?

[..]In the intro to the article, you mention two of the ways to get higher magnification out of a 1x macro lens, but you leave out what is potentially the best way, reversing it not on extension tubes but on a tube lens. I think it would be a more complete article if you mention that option and its...
by enricosavazzi
Tue Oct 13, 2020 12:24 am
Forum: Equipment Discussions
Topic: Can I push the resolution of a 1:1 macro lens?
Replies: 23
Views: 1125

Re: Can I push the resolution of a 1:1 macro lens?

As I explained above, with modern lenses that have floating elements, you should have used a teleconverter instead of extension tubes. Otherwise you aremoving the lens far from ist design point. I just published a page on my site dealing with tests of four legacy macro lenses with a 2x teleconverte...
by enricosavazzi
Sun Oct 11, 2020 7:28 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Effective aperture with teleconverter + macro lens
Replies: 6
Views: 250

Effective aperture with teleconverter + macro lens

Let's see whether I understand the problem correctly, or I am making a mistake somewhere. We assume that the pupil ratio is 1 for simplicity, so the effective aperture A' is A' = A * (m + 1) where A is the nominal aperture, and m the magnification. So if we focus a lens at m = 2 by extension alone (...
by enricosavazzi
Fri Oct 09, 2020 9:37 am
Forum: Equipment Discussions
Topic: Olympus BX stage keeps drifting down, "focus shifting".
Replies: 20
Views: 659

Re: Olympus BX stage keeps drifting down, "focus shifting".

[...] I am using BX53 stand just to clarify, very interesting pointers about provis models, well I really like 53 because it has small footprint and does not take much space on my very busy table! [...] Indeed, the Provis stand weighs north of 50 kg "naked", needs a strong table, and most functions...
by enricosavazzi
Thu Oct 08, 2020 12:02 pm
Forum: Equipment Discussions
Topic: Olympus BX stage keeps drifting down, "focus shifting".
Replies: 20
Views: 659

Re: Olympus BX stage keeps drifting down, "focus shifting".

The following information does not help if you already have a BX series microscope, but it is related to thermal drift so it might be interesting nonetheless. A couple of years ago, I ended up ordering an Olympus AX70 stand. It ended up being lost in the mail and eventually returned to the sender, s...
by enricosavazzi
Sun Oct 04, 2020 2:56 am
Forum: Equipment Discussions
Topic: Olympus BX stage keeps drifting down, "focus shifting".
Replies: 20
Views: 659

Re: Olympus BX stage keeps drifting down.

Just in case, check the friction/brake on the focusing rack before you do any maintenance. This lever may be set too loose. The lever that controls friction is located between the left coarse focus knob and the stand.
by enricosavazzi
Sat Oct 03, 2020 2:01 am
Forum: Equipment Discussions
Topic: DIY Fluorescence with Zeiss fluoro condenser - help needed
Replies: 72
Views: 5017

Re: DIY Fluorescence with Zeiss fluoro condenser - help needed

This thread is already quite long, so I might be repeating some information already state above. However, here it goes: Non-stained acrylic (=Plexiglas and other names in commercial nomenclature) transmits UV well into the UVB range. Many Acrylic formulations have UV-absorbing dyes mixed in, but not...
by enricosavazzi
Tue Sep 22, 2020 12:01 am
Forum: Equipment Discussions
Topic: UV against lens fungus
Replies: 3
Views: 484

Re: UV against lens fungus

Can UV light stop fungus growth inside objective ? The most effective wavelengths for this use are in the UVB and UVC. Most lenses (except the very few ones designed for UV imaging and a handful more) transmit little to no UVA, and no UVB and UVC, so exposing these lenses to UVB and UVC has no effe...
by enricosavazzi
Sun Sep 13, 2020 2:10 am
Forum: Equipment Discussions
Topic: Question about window on the underside of Olympus trinocular head
Replies: 24
Views: 1642

Re: Question about window on the underside of Olympus trinocular head

In a worst-case scenario, the window may have been computed as part of the optical system w.r.t. axial chromatic aberration, and removing it may increase said aberration. I have seen several examples of optical windows in Olympus infinite microscopes where a thick optical window has a thin cladding ...
by enricosavazzi
Fri Sep 11, 2020 12:09 am
Forum: Macro & Microscopy Articles
Topic: Anesthesia, analgesia, and euthanasia of invertebrates
Replies: 0
Views: 1098

Anesthesia, analgesia, and euthanasia of invertebrates

Cooper 2011 - Anesthesia, analgesia, and euthanasia of invertebrates. ILAR Journal 52 (2): 196-204

https://academic.oup.com/ilarjournal/ar ... 52-196.pdf
by enricosavazzi
Tue Sep 08, 2020 3:57 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Tranforming diatoms into magnesium replicas
Replies: 5
Views: 775

Re: Tranforming diatoms into magnesium replicas

bralex wrote:
Tue Sep 08, 2020 3:41 pm
I think he's saying "magnesia" not "magnesium" when he talks about the replica.
That would explain it. Magnesia is magnesium oxide, so he may have said the right thing after all.
by enricosavazzi
Tue Sep 08, 2020 12:32 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Tranforming diatoms into magnesium replicas
Replies: 5
Views: 775

Re: Tranforming diatoms into magnesium replicas

The speaker does say "magnesium replica", but the formula shown in the presentation seems to say that the replica material is magnesium oxide . While metallic magnesium is opaque to VIS (albeit very reflective), magnesium oxide is trasparent from NUV to IR, see https://www.osapublishing.org/josa/abs...
by enricosavazzi
Tue Aug 25, 2020 10:20 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Questions for the experts.
Replies: 12
Views: 1250

Re: Questions for the experts.

I will leave some answers to others, but can say that vibration in your setup seems to take an excessively long time to settle at 10x, so you should try to solve this problem. For example, mounting the XY stage atop the scissor jack is probably not the best idea. I would try to reverse the order and...
by enricosavazzi
Mon Aug 17, 2020 5:01 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Would you recommend a tripod or monopod for macro in the field?
Replies: 23
Views: 3745

Re: Would you recommend a tripod or monopod for macro in the field?

Hi, Thanks everyone for the suggestions. @Dalantech That's a great idea. It doesn't lend itself to my usual setup with a 105 mm lens (my hands aren't that big :wink: ) but I recently started using the EF-S 24mm for macro, which would be suitable. Still have to figure out if I need to drink more or ...