BadScience

Works as a Nuclear Materials Engineer
Joined on Feb 3, 2012

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On photo Mt Hood Winter Camping in the Moonlit night landscape ... no milky way! challenge (12 comments in total)
In reply to:

BadScience: hmmm.

30 seconds, blurred coulds but no star trails?

yes, but its a 30 second exposure with a 28mm lens? I would expect much longer trails than here. Anything above 5 seconds is normally a bit dodgy. Looks like two exposures to me: especially considering that the stars behind the clouds are as bright as those not hindered by clouds. Nothing wrong with that, but should be stated if it is.

Link | Posted on Jul 29, 2018 at 17:48 UTC
On photo Mt Hood Winter Camping in the Moonlit night landscape ... no milky way! challenge (12 comments in total)

hmmm.

30 seconds, blurred coulds but no star trails?

Link | Posted on Jul 26, 2018 at 21:34 UTC as 1st comment | 4 replies
In reply to:

23NR Photography: Ireland is not in the UK...

"Ugandan engineer does not rely on the skin color but the fact that Romania is part of Europe when Uganda is not..."

yes, and one is essentially a proxy for the other. The native white population of Uganda is approaching zero. The native black population of Romania is approacing zero.

I'm sorry, but the immigration policies of the EU are discriminatory. Why the hell should a European be in front of an African in the queue to come and work in the UK? Why do Europeans need special status?

Saying "its in Europe" is irrelevent. That's a quirk of georaphy and pure luck. Nobody can choose where they are born. If the USA had a policy of preferring European to African immigrants there would be outrage. And rightly so.

To allow preferential immigrant status because of where you are coming from is not fair, it is immoral and should be illegal. And hopefully, very soon, in the UK it will be illegal.

Link | Posted on Jul 26, 2018 at 21:29 UTC
In reply to:

23NR Photography: Ireland is not in the UK...

Ken, I've worked in Uganda - and I am white - so can confirm what you claim is bullsht.

The EU has it enshrined in the constitution that foreigners from one EU country working in another EU country has preferential rights to foreigners from outside the EU. It enshrines in law two types of foreign national.

I'm not sure of many African nations that have such enshrined in their constitution.

Link | Posted on Jul 23, 2018 at 20:46 UTC
In reply to:

23NR Photography: Ireland is not in the UK...

dick in the UK

At the moment the EU legally profiles - essentially - by race. The vast majority of Europeans are white. People from EU countries are allowed to move and work freely in any other EU country to the detriment of people from outside of the EU.

To put it bluntly, a white Romanian beggar has absolute right to travel to London to find work. A black Ugandan engineer does not.

The situation is so absurd that professional Africans have to jump through hoops to work in Europe to the extent that it is easier to be smuggled into Europe from Africa than it is to get a work visa.

When it comes to racial profiling, the EU have got it nailed. Masters of the art.

Link | Posted on Jul 23, 2018 at 20:02 UTC
On article Kodak teases first sample photos of Ektachrome (196 comments in total)
In reply to:

Scott Eaton: No self respecting commercial photographer will touch 35mm tranny film, but the broader point is the fans of these retro film's aren't really interested in creating good images. Just look at the samples.The internet will soon be full of really bad dSLR scans of this film of really bad subject matter, but other film shooters will keep hitting the like button. The new Ektachrome could produce polka dot highlights and neon shadows, but that's not the point. That's 'artistic'. It's like preferring VHS over digital HD because you can't take good HD movies.

"many"
"plenty"

these words are essentially meaningless; do you care to put numbers?.

Hence, in your own words
"slide film *WAS* the standard for publications"

What fraction of published photographs, say in the National Geographic (which you used as an example) are STILL shot on 35mm slide film?

I'll take a punt that the answer is, rounded down to the nearest whole number, zero. I'm sure you'll agree, as per your orignal assertion.

Link | Posted on Jun 16, 2018 at 13:10 UTC
On article Kodak teases first sample photos of Ektachrome (196 comments in total)
In reply to:

Scott Eaton: No self respecting commercial photographer will touch 35mm tranny film, but the broader point is the fans of these retro film's aren't really interested in creating good images. Just look at the samples.The internet will soon be full of really bad dSLR scans of this film of really bad subject matter, but other film shooters will keep hitting the like button. The new Ektachrome could produce polka dot highlights and neon shadows, but that's not the point. That's 'artistic'. It's like preferring VHS over digital HD because you can't take good HD movies.

danart - the pertinent word of your first sentence is "was".

Link | Posted on Jun 13, 2018 at 23:57 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

"the force is pushing period"

What is generating this force? Where is the energy coming from?

You seem to be stuck in this hole that pushing is "correct" and pulling is "incorrect"; its wooly thinking that is stopping you from understanding the actual mechanism. Try to drop the words completely and define suction purely in terms of a pressure vector.

I gave you links to tens of thousands of peer reviewed papers. You chose one from India. I don't know the paper, or why you picked that one, but a peer reviewed paper will offer you more understanding that a reddit thread or a science fiction author. You need to understand the fundamental mechanics.

Like I offered...you can contact me off this thread and I can link you in to our research group. You will learn more than from a reddit thread. Otherwise you are just derailing this further. I can see that you are getting more and more confused and it is probably not in your best interests to get even more confused.

Link | Posted on May 28, 2018 at 17:06 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

I am quite happy to take this offline, rather than de-rail this thread further.
I can direct you towards my research group, and the work we do, some of which is directly related to bulk flow of fluids across a pressure drop.

Link | Posted on May 28, 2018 at 15:28 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

no it is not ok.

I will define the word precsely for you
suction
The bulk movement of a fluid flowing down a pressure gradient.

There is a statistical bulk movement from regions of high concentration to low concentration. It happens down temperature gradients, chemical gradients, pressure gradients, etc.

that's it.

There is no illusion. You have a problem with "pulled" but not "pushed" (which is bizarre). You really should understand why these words do not give you an understanding before trying to convince others (what is doing the "pushing"? What is generating the "pushing" force - if there is one. What is the direction of this force in relation the the motor doing the work? So is it a push or a pull?

(What has India got to do with relevance of the science?)

Link | Posted on May 28, 2018 at 15:27 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

cosina -"without atmospheric pressure what you call suction could not occur"

That is absolutely incorrect.

You need two pressures pa; pb

where pa>pb

that's it.

The bigger the value of dp/ds (change in pressure/change in distance) the greater the suction.

Vacuum cleaners work by having a dp of roughly -15Kpa over a short distance, just 10s of centimetres (or whatver the distance from the motor to the nozzle is.)

There is nothing special about the mean pressure of the earth's atmosphere at sea level. What is "special" is dp/ds.

Suction occurs everwhere in the universe where this occurs.

fluid flows from low pressure to high pressure. It is a statistical phenomeon described by Boltzmann mechanics. The correct scientific term for this is suction;just do a cursory review of the literature:
https://scholar.google.co.uk/scholar?hl=en&as_sdt=0%2C5&q=suction&btnG=

" just not in physics'
What exatly is your training in physics?

Link | Posted on May 28, 2018 at 11:19 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

Roland, that's just how humans percieve temperature
https://en.wikipedia.org/wiki/Thermoreceptor
(btw temperature and heat are not the same thing. An object has a temperature, heat is the flow of energy)

Cosina
suction is NOT an illusion.
It is the name given to the phenomena when bulk fluids move from high pressure to a lower pressure. Atmospheric pressure is not a special defining factor other than we happen to live surrounded by fluid at atmospheric pressure, and so 1 atm tends to be a standard measure. It is the gradient that is the factor. You can generate suction at ANY two pressures. The greater the pressure gradient, the greater the rate of flow, hence vacuum cleaners generate a lower pressure (say -15kPa) compared to the surrounding air. The lower the pressure, the greater the suction..

The defintion of suction is the change in pressure, so if the pressure gradient from the pump of a vacuum cleaner to the air is -15 Kpa, that is the value of the suction.

Link | Posted on May 27, 2018 at 19:26 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

Tommi K1
"Heat doesn't radiate."

jesus wept, ...
The DEFINTION of heat is the radiation of (non-work) energy.

I have no idea what that second paragraph of yours means. It is gobbledegook.

--------
cosinaphile:-
"we think only high energy things glow and radiate but everything does"

who is "we"? (and define "high energy")
https://en.wikipedia.org/wiki/Maxwell–Boltzmann_distribution#Distribution_for_the_energy

Link | Posted on May 27, 2018 at 18:41 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

* meant gradient in the pressure

Link | Posted on May 25, 2018 at 14:06 UTC
In reply to:

dan pv: "The compression you get using a long lens isn't a result of the lens, so much as the distance between your subject, your background, and the camera."

That's not true. If you keep unchanged the distance between your subject, your background, and the camera and use a tele lens instead of a normal one , assuming theoretical lenses with infinite DOF, the perspective will seam compressed. The perspective itself doesn't change. What changes is the crop factor of the image. Our brain is used with normal angle of view images and it interprets the cropped image as a normal image. This creates the sensation of compressed perspective. And this sensation is entirely the result of the crop factor induced by the tele lens.
Of course that by changing the distance between your subject, your background and the camera one can produce a sort of "compressed perspective" image, too. But it has nothing to do with "lens compression".

an example in art it the Last Supper which was painted at the end of a corridor.

Viewed close up, or reproduced in a book or on a screen, you lose the sense of perspective.

Link | Posted on May 25, 2018 at 12:03 UTC
In reply to:

photophile: OK. Interesting video and thank you for taking the time to illustrate - but seriously ? FEET??? What is that? How many feet in a gallon?

he asked how many feet in a gallon,

of which there is no answer, certainly not the anwer you gave.

length and volume are not the same thing.

Link | Posted on May 25, 2018 at 12:01 UTC
In reply to:

cosinaphile: and vacuums don't suck air in... it is yet another cognitive illusion , real enough but not for the reasons we imagine

vacuums work because of the external pressure of our atmosphere vacuums remove the pressure and atmosphere rushes in ....it is pressure not suction

yet it still feels like vacuums suck ....go figure

suction IS a change gradient.

These words mean exactly the same thing.

If you have a pressure gradient, air will move.

It wil move from high pressure to low pressure.

It is how our weather works

It is how "vacuum" cleaners work.

It is a fundamental Thermodynamics.

Roland. Heat radiates the same way, from high to low. "Cold" does not radiate, it just feels like that on your skin. Its an illusion that evolved in our ancestors to make sure they kept warm and alive. You will also feel exactly the opppsite effect near a fire and you will feel the heat radiate.

Things will "feel" too cold or too warm on our skin so we ensure we stay at the same temperature.

Link | Posted on May 25, 2018 at 11:46 UTC
In reply to:

dprived prev: good points clarifying common mistakes in use of technical terms here ...

by the same token, many people so wrongly believe "using slower (longer) shutter speeds (say below 1/30th") with a wide angle lens on a hand-held camera captures the shot sharp and non-blurry, while doing the same with a telephoto lens can results in blurry images due to hand shake ..."

that is also another myth because in both cases the shots ARE blurred but the one taken with a wide angle lens only shows it less, NOT removes the blur totally!

why: both shots are taken with the same shaky hands, thus resulting in blurred images!

wish someday people will also realize common mistakes in using technical terms doesn't mean film photography can be called "analog" in comparison to digital!

(the last statment here will most probably stir some arguments on this thread ... just wait and see!) ;-)

it is NOT an incorrect belief.

It is a sound beief because it is based on a physical fact.

it depends upon the angular displacement.

For a given displacement (hand movement):

on a wide angle lens, this could amount to a blur of less than a pixel (or a grain)- the image will look sharp.

On a telephoto lens, this could amount to a blur of several tens of pixels - the image will look very blurred.

Blur has a definition. It changes due to the angular displacment. Minimizing this reduces blur.

You can easily do the maths to prove this to yourself. You can define a circle of confusion, define a partcular angular displacement and plot these against focal lenghts.

hence the reciprocal focal length rule. It is a good rule of thumb.

Link | Posted on May 25, 2018 at 11:34 UTC
In reply to:

MarioV: Some of the brighter stars in the milky way area have begun to trail due to the 25 sec exposure, and need to be rounded in post.
Other than that, its an image that I would be proud of.
Excellent work.

Here we have a grown man who has not mastered his two times table - usually mastered by toddlers and sheep dogs - preaching about his certainty on the descent of man.

The internet gave the world wonderful things. It also gave a voice to terminal fools.

Link | Posted on Dec 11, 2017 at 13:33 UTC
In reply to:

George Veltchev: pulling the shadows out with a Canon 6D MarkII is painfully difficult task as we all know. No need to provide poetic evidence , Canon .... nothing can save the troubled model !

when the shadows are black the shadows are black (bright day); when the shadows are bright, the shadows are bright....

Those images are all corrected for *print*. Many of them are competition winners and used by the National Parks service and Nasa in their literature.

That's correct exposure...maybe you are used to fake HDR or highly processed images when the contrast is dialled right down? (your gallery sucks...and that's not a humble opinion...its an objective fact). Maybe you could point to one that is "unbalanced" and compare it one of your images that is "balanced")?

there was an article on this site a few months ago by a professional photographer about the current trend of not allowing shadows to be black....and how it is a trend that should be avoided. You should read it.

Unless there is good reason not to, blacks should be black and whites should be white.

You need to practice more...

Link | Posted on Dec 10, 2017 at 13:11 UTC
Total: 1222, showing: 1 – 20
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