Search found 603 matches

by Phill Brown
Sat Mar 16, 2024 6:58 am
Forum: Illumination Techniques
Topic: BH-2 and darkfield
Replies: 2
Views: 343

Re: BH-2 and darkfield

Low power condensers are the least suited to DF. Dry will be limited to 0.85 realistically but 0.75 is a more likely limit for 1.25. Oil would be for 0.5 to 0.9,lower na objectives will only have the centre illuminated. There are exceptions as always. If you have a phase telescope and a slide ringin...
by Phill Brown
Thu Mar 14, 2024 10:28 pm
Forum: Microscopy accessories
Topic: 1/4 wave filter source
Replies: 13
Views: 1734

Re: 1/4 wave filter source

I've only seen bonded to make a single element filter.
by Phill Brown
Fri Mar 08, 2024 9:52 pm
Forum: Illumination Techniques
Topic: Condenser Alignment.
Replies: 17
Views: 974

Re: Condenser Alignment.

Think you'll find the yellow and blue fringing is how the subject edges are illuminated,the objective can't do a busting lot about it.
by Phill Brown
Fri Mar 08, 2024 7:16 pm
Forum: Illumination Techniques
Topic: Condenser Alignment.
Replies: 17
Views: 974

Re: Condenser Alignment.

But I do notice a small coloration off to one side of field dia. during Kohler alignment. This is more obvious when condenser is oiled which minimizes reflections between condenser and slide. I'll have to examine this later thanks to your post. Thanks, Glenn Likewise, I never tried centration of th...
by Phill Brown
Wed Feb 28, 2024 10:57 am
Forum: Beginner's corner
Topic: New Technique
Replies: 4
Views: 463

Re: New Technique

G4 sockets allow for error in filament placement. Custom bulbs with a collar require a jig to focus the collar fitment precisely. Probably not a good idea to run 6v 30w on a supply intended for 20w. 6v @ 30w is 5 amps. 6v @ 20w is 3.5 amps. Either the voltage will be low and give a warm tint or the ...
by Phill Brown
Fri Feb 23, 2024 3:56 pm
Forum: Home-made microscope adaptations
Topic: How to Diy objective parcentering.
Replies: 6
Views: 723

Re: How to Diy objective parcentering.

Another great contribution thanks. Striving for perfection in production is the biggest waste of time and money resulting in bankruptcy or buy out. There is an agreed standard, sometimes that is exceeded by chance. Below that is usually left for the phase B tester to dispute and resolve. The intende...
by Phill Brown
Wed Feb 21, 2024 7:56 am
Forum: Introduce yourself
Topic: Never too late
Replies: 2
Views: 515

Re: Never too late

Happy days.
We have Watson and V***ers in the UK.
It's a slippery slope if you don't have a lot of space, the Watson microsystem 70 cases are designed to be stacked.
Good luck from sunny Devon.
by Phill Brown
Tue Feb 20, 2024 3:26 pm
Forum: Microscopes and optics
Topic: Is it ok to use metalloscopy objective in biology microscope?
Replies: 8
Views: 661

Re: Is it ok to use metalloscopy objective in biology microscope?

Optimised for epi illumination?
What 10x do you have?
by Phill Brown
Tue Feb 06, 2024 9:03 am
Forum: Pictures and Videos
Topic: Collection of live round Diatoms
Replies: 2
Views: 313

Re: Collection of live round Diatoms

Excellent, thanks for sharing your find.
by Phill Brown
Fri Feb 02, 2024 4:11 pm
Forum: Illumination Techniques
Topic: Has anyone ever used LWD condenser?
Replies: 8
Views: 944

Re: Has anyone ever used LWD condenser?

More useful for inverted scope.
Would work ok for lower na, maybe 2x.
by Phill Brown
Wed Jan 31, 2024 10:54 am
Forum: Microscopes and optics
Topic: Which 40x and 4x objectives for Nikon Labophot?
Replies: 16
Views: 1194

Re: Which 40x and 4x objectives for Nikon Labophot?

The light source is the cause. LED systems with pretend Kohler will have similar aberrations. It's just the way things are. The objective can't fix the problem. It could be cost effective to pick up a Labophot 2 with a dead PSU but working fine focus and add a variable 12v 5A DC supply. There are 2 ...
by Phill Brown
Tue Jan 30, 2024 12:42 pm
Forum: Microscopes and optics
Topic: Which 40x and 4x objectives for Nikon Labophot?
Replies: 16
Views: 1194

Re: Which 40x and 4x objectives for Nikon Labophot?

Close and focus on the Kohler iris. There will be coloured edges. LED is the cause not the objective. There are but the colours vary according to the objective. I can almost get rid of the edges when everything is properly aligned, especially with the Plan Apo and Fluor objectives. 100% what I woul...
by Phill Brown
Mon Jan 29, 2024 7:40 pm
Forum: Microscopes and optics
Topic: Which 40x and 4x objectives for Nikon Labophot?
Replies: 16
Views: 1194

Re: Which 40x and 4x objectives for Nikon Labophot?

Close and focus on the Kohler iris.
There will be coloured edges.
LED is the cause not the objective.
by Phill Brown
Mon Jan 29, 2024 10:14 am
Forum: Microscopes and optics
Topic: Which 40x and 4x objectives for Nikon Labophot?
Replies: 16
Views: 1194

Re: Which 40x and 4x objectives for Nikon Labophot?

If you like yellow and blue fringing LED is an upgrade.
by Phill Brown
Sun Jan 28, 2024 10:05 pm
Forum: Microscopes and optics
Topic: Which 40x and 4x objectives for Nikon Labophot?
Replies: 16
Views: 1194

Re: Which 40x and 4x objectives for Nikon Labophot?

Something is out of alignment.
Wrong bulb or LED "upgrade".
Unlikely to be the objectives.
by Phill Brown
Tue Jan 23, 2024 4:58 pm
Forum: Microscopes and optics
Topic: DIC for birefringent objects
Replies: 9
Views: 829

Re: DIC for birefringent objects

I'd wonder about the mountant being an issue.
by Phill Brown
Thu Jan 18, 2024 11:50 am
Forum: Microscopes and optics
Topic: Has anyone compared Chinese objectives to similar objectives from the Big Four?
Replies: 3
Views: 726

Re: Has anyone compared Chinese objectives to similar objectives from the Big Four?

More than anything if the slide clamp is up to holding a slide and the plastic mechanical parts hold up.
There's the yellow and blue fringing from the pretend Kohler and LED to deal with.
The objective can only do so much.
by Phill Brown
Thu Jan 11, 2024 10:01 pm
Forum: Pictures and Videos
Topic: Fossil diatom from Oamaru
Replies: 33
Views: 33228

Re: Fossil diatom from Oamaru

Sticking with 275.
by Phill Brown
Sun Jan 07, 2024 7:50 am
Forum: Beginner's corner
Topic: Inverted scope
Replies: 14
Views: 12970

Re: Inverted scope

Best avoid anything that looks like it's already lived in marine biology labs.
Good luck with finding a bargain, they are available.
by Phill Brown
Sat Jan 06, 2024 12:14 pm
Forum: Beginner's corner
Topic: Inverted scope
Replies: 14
Views: 12970

Re: Inverted scope

The biggest difference is the cleaning of samples. Residues will quickly settle Infront of the subjects. Settling and rinsing may or may not be interesting. DF is more challenging but what is life without taking some on. You should get a lot for the equivalent budget. I don't use mine much but would...
by Phill Brown
Fri Dec 22, 2023 12:48 pm
Forum: Beginner's corner
Topic: Tools for dissecting really tiny spiders and insects
Replies: 6
Views: 4040

Re: Tools for dissecting really tiny spiders and insects

000 sable brushes are worth trying for moving things with minimal damage.
by Phill Brown
Wed Dec 20, 2023 9:28 am
Forum: Microscopes and optics
Topic: Thoughts on these microscopes for sale on Facebook appreciated
Replies: 7
Views: 7669

Re: Thoughts on these microscopes for sale on Facebook appreciated

Definitely a junk pile of projects.
If the labophot 2 PSU is working it may be viable, Labophot 2 complete with failed PSU are cheap and abundant.
by Phill Brown
Thu Dec 14, 2023 8:42 pm
Forum: Pictures and Videos
Topic: Fossil diatom from Oamaru
Replies: 33
Views: 33228

Re: Fossil diatom from Oamaru

I'll kick off with 275 microns ish across the round diatom.
by Phill Brown
Tue Dec 12, 2023 7:31 pm
Forum: Beginner's corner
Topic: Question Regarding Darkfield Condensers
Replies: 39
Views: 115039

Re: Question Regarding Darkfield Condensers

I'm confident you will enjoy the DOF from x40 .65 far more than the resolution at the limits.
X20 .5 is great when you train yourself to see what is there.
Get some bargain diatom strew slides from eBay and just have fun with it.
by Phill Brown
Tue Dec 12, 2023 2:50 pm
Forum: Beginner's corner
Topic: Question Regarding Darkfield Condensers
Replies: 39
Views: 115039

Re: Question Regarding Darkfield Condensers

How long is the lag from posting here to when it appears on their site?
by Phill Brown
Mon Dec 04, 2023 9:27 pm
Forum: Miscellaneous
Topic: A discussion about experience
Replies: 39
Views: 33921

Re: A discussion about experience

As a thought experiment. While in a room you look at the ceiling. You know what is beyond it but you have to devise an experiment for someone who has never been outside that there is anything beyond the boundary they can see. It's easier to see with reasoning that what is beyond is still there. We c...
by Phill Brown
Mon Dec 04, 2023 1:49 pm
Forum: Miscellaneous
Topic: A discussion about experience
Replies: 39
Views: 33921

Re: A discussion about experience

Looking into the microscope is not without risk.
Go with the flow.
Some of the greatest insights come from polymaths.
Whether to listen to under milk wood or choosing with great consideration what not to own.
by Phill Brown
Sat Dec 02, 2023 1:31 pm
Forum: Illumination Techniques
Topic: Darkfield diagnostic test slide
Replies: 26
Views: 68232

Re: Darkfield diagnostic test slide

Phill Brown; Isn't it simpler to imagine that a bit of Cedarwood oil has leaked in through the top (??) I can imagine that. Light enters in a relatively straight path from air to glass. When it passes back to air is in the objective in a relatively straight line. It's a reflector that gives an illu...
by Phill Brown
Sat Dec 02, 2023 1:01 am
Forum: Miscellaneous
Topic: A discussion about experience
Replies: 39
Views: 33921

Re: A discussion about experience

Complex replication of replacement parts. Experimental solutions to conditions that are in the future. Perfect solutions to an environment that changed become redundant. Energy is transformed by interaction. It's not impossible to transform from something that can be measured to something that we no...
by Phill Brown
Fri Dec 01, 2023 8:07 pm
Forum: Illumination Techniques
Topic: Darkfield diagnostic test slide
Replies: 26
Views: 68232

Re: Darkfield diagnostic test slide

I'll take a guess that the oil is about the boundary to the top glass. As it wasn't feasible to make from a solid. It has no air. On the one I have with discoloured oil I got a small bubble from warming it to get the gummy aperture to let go. Possibly originally assembled submerged in oil. Got the b...