Random Photos

[Ibix]

So that's where Frida Kahlo is from?
View attachment 323110

Her father was German, according to her Wiki article. She herself was Mexican.

 

[gmax137]

Frida Kahlo

My wife & I were visiting Mexico City. We saw her house and took the tour without knowing anything about her beforehand. Very cool.

 

[BillTre]

My wife & I were visiting Mexico City. We saw her house and took the tour without knowing anything about her beforehand. Very cool.

There is also a good movie about her life.

 

[berkeman]

My wife & I were visiting Mexico City. We saw her house and took the tour without knowing anything about her beforehand.

I had issues parsing this, until I realized that you were replying to the post above yours. Doh!

 

[DennisN]

So that's where Frida Kahlo is from?

I think so. According to Frida (given name) (Wikipedia):

Frida (with variants Freda, Frieda, Frinta and Freida) is a feminine given name. In central and eastern Europe, Frida is a short form of compound names containing the Germanic element fried meaning "peace".

And according to this Swedish wikipedia page (translated with Google translate):

Frida is an Old Norse female name formed from the word fridh which means the beloved, the beautiful. It is also a short form of German names such as Frideborg, Alfrida, Elfrida and Valfrida. The oldest evidence in Sweden is from the year 1388.

Edit: Though I got a bit confused by the Swedish Wikipedia page saying "fridh" means "the beloved, the beautiful", because there is a Swedish word "frid" which means "peace" (or "calm"), which seems to correspond to the quote from the English wikipedia page above.

 

[BillTre]

from CNN:

 

[morrobay]

Here two of my half Japanese nephews in Philadelphia. The one on left just completed masters in electrical engineering at University of Pennsylvania. And already has job at Ford motor company in Michigan.

 

[Tom.G]

The one on left . . .

And the one on the right?

 

[morrobay]

And the one on the right?

Freshman engineering/business major at University of Rochester.

 

[Andy Resnick]

After patiently waiting for 10+ years (!!!), a 35mm faceplate for a Zeiss Ultraphot II became available on ebay and I immediately grabbed it. I have an Ultraphot III, but the piece fits well enough to use. Here's a quick pic of the new setup, with a dummy camera mounted where my Nikon camera goes:

Before, my use of a camera on the Ultraphot was somewhat restricted- I could "only" use the extended optical path (designed for 4x5 film) like this:

I'm not complaining- the image quality is fantastic- but I could only image using epi-brightfield. And, while I have the 4x5 film holder, medium-format film is not a road I am ready to travel down.

Photography using the 'normal' imaging path is restrictive because the image circle is about 22mm (C-mount specification), resulting in images looking like this (8x epi-darkfield):

It doesn't look terrible unless you look closely: off-axis the image degradation (chromatic aberration, field curvature, etc.) happens fast- here's a 1:1 crop just off of center:

Using the 35mm film adapter, the image circle is magnified to better fill the sensor:

And while there is now some distortion and field curvature (which I think I can correct), the off-axis image characteristics are much improved: note that this crop has been downscaled about 60% to approximate the field of view of the prior crop:

However, the real leap forward is not the image quality, it access to different imaging techniques- techniques that I could not use for photography because the luminar head doesn't support techniques like darkfield, polarization, DIC, phase contrast.... but now I can! Here's a epi-DIC image (downscaled to 800 pixels wide) using a 40x lens:

I feel like I unlocked a whole bunch of new features! In practical terms, this means I have about 20 lenses that I can now use to give me (hopefully) amazing photographs. Currently, the only significant non-fluorescent imaging modality I can't do is epi-phase, and I am close to being able to implement that- I'm curious what epi-phase images look like since I have never seen any, anywhere.

 

[BillTre]

Nice picture of Portland's Japanese garden (not taken by me):

 

[DennisN]

One small step for a yeti...

...one giant leap for yetikind.

We've got a bit of snow storm in the city... it was fun to be out and shooting, and I was happy that my camera is weather sealed, because this time it sure was needed .

 

[DennisN]

A piece of ice:

 

[Borg]

Looks like a Dalek firing a death ray.

 

[Andy Resnick]

Self-portrait (I licked a slide):

100x phase contrast oil objective (transillumination). It's an epithelial cell, the center oval is the nucleus. The slightly out-of-focus lines are crosshairs from a focusing aid buried deep inside the camera adapter.

 

[DennisN]

Self-portrait (I licked a slide):

So it is a cellfie?

 

[DennisN]

Two tulips in May last year:

(Lens used: my cheap but very nice Konica 40mm f/1.8)

 

[DennisN]

A beautiful photo of a squirrel here on flickr.
(you have to click on the link above, I can't hotlink it in the post)

 

[BillTre]

A beautiful photo of a squirrel here on flickr.
(you have to click on the link above, I can't hotlink it in the post)

Nice.
Here you go, screenshot:

 

[Andy Resnick]

So it is a cellfie?

Noice!

 

[dlgoff]

My daughter and her dog:

 

[berkeman]

My daughter and her dog:

Does she put goggles on the pup when she takes them flying?

 

[dlgoff]

Does she put goggles on the pup when she takes them flying?

View attachment 323708

I think it might be too dangerous to have him in the cockpit when flying. He would probably freak out.

 

[morrobay]

Mosquito netting Sunset

 

[DennisN]

"Thingies" on a tree (I don't know what they are called) (taken last year):

 

[Tom.G]

For for lack of further information, I would call them Seed Pods.

You might try cropping to a single one then ask Google for an image match. (I've never tried it, but others keep mentioning the possibility. )

 

[DennisN]

For for lack of further information, I would call them Seed Pods.

You might try cropping to a single one then ask Google for an image match. (I've never tried it, but others keep mentioning the possibility. )

I frequently use Google image search to identify plants, and I tried with this (entire) photo too without success. But I will try with a crop of a single one instead, thanks for the idea!

 

[DennisN]

For for lack of further information, I would call them Seed Pods.

I think that is correct... I found a page here:
Types of Tree Seed Pods – Identification Guide With Pictures (LeafyPlace)

 

[morrobay]

There are occasions: The good thing about the system in Thailand is you can walk in and see a specialist.

 

[Andy Resnick]

A few preliminary images using crossed polarizers:

Caffeine crystals ('psychedelic spaghetti') at 16x

Potassium permanganate (also 16x)

Sodium Iodide (an ingredient in "elephant toothpaste") at 8x.

The colors arise because nearly all crystals are birefringent, the total phase difference between ordinary and extraordinary rays ('retardation') is what is visualized as color. Prepping these samples, if you have the needed equipment, is trivial. Start with a saturated solution, I applied 5-10 microliters (uL) to a glass slide and let the sample dry. Not sure about adding a coverslip to prevent ageing- that's next on the list- because I don't want to crush the sample.

But, since (nearly) all crystals are birefringent, I can also look at biological materials. A potato, for example:

Starch grains@ 10X.

Tree bark @ 8x

Bone (compact, cross section) @ 8x

Hair (human, scalp section) @ 4X.

 

[morrobay]

A few preliminary images using crossed polarizers:

View attachment 323975
Caffeine crystals ('psychedelic spaghetti') at 16x

View attachment 323976
Potassium permanganate (also 16x)

View attachment 323977
No

The colors arise because nearly all crystals are birefringent, the total phase difference between ordinary and extraordinary rays ('retardation') is what is visualized as color.

View attachment 323979
Starch grains@ 10X.

View attachment 323980
Tree bark @ 8x

View attachment 323981
Bone (compact, cross section) @ 8x

View attachment 323982
Hair (human, scalp section) @ 4X.

Hello, How exactly is the ' total phase difference between ordinary and extraordinary rays visualized as color? Would that be from constructive/destructive interference?

 

[morrobay]

The South West Wind and Cappuccino effect

 

[DennisN]

A few preliminary images using crossed polarizers:

Very cool photos!

Potassium permanganate (also 16x)

Amazing colors!

medium-format film is not a road I am ready to travel down

Hehe, it's another rabbit hole...

I've actually got two medium-format lenses in my collection. They were so cool that I couldn't resist them on an online auction, and I got them quite cheap. They are the oldest lenses I have. But I can't use them since I haven't found any adapter for them. Maybe I'll try building one myself someday, we'll see.

Here they are:

Carl Zeiss Jena Tessar 105mm f/3.5 (from the 1950s) (mount: Pentacon Six)
(note the 15 bladed aperture (!), quite cool)

Here beside my camera:

Carl Zeiss Jena Tessar 150mm f/4.5

 

[Andy Resnick]

Hello, How exactly is the ' total phase difference between ordinary and extraordinary rays visualized as color? Would that be from constructive/destructive interference?

Oh sure... ask me to explain something I just learned about :)

(Optical) Minerology is a "delightful" blend of ray and wave optics, the main conclusion of which is the "Michel-Lévy interference color chart" (a good online explanation: https://www.mccrone.com/mm/the-michel-levy-interference-color-chart/). My reference is an excellent book I inherited from my doctoral advisor- lots of diagrams- which is currently in my office. So I don't want to mangle an explanation right now. I'll provide a better explanation shortly.

 

[BillTre]

Here's a striking picture:

NatureSMS https://www.facebook.com/naturesms0/photos