What Do Smart Phones (Partially) Replace?

[sophiecentaur]

Using that same smart idea I used my phone as protection etc. to view the recent solar eclipse. So, here's one more: Solar [Eclipse] Glasses ...
[It worked + taking pictures too ...]

That system may not always be safe for the poor old sensor. A camera with a shutter and mechanical aperture stop will limit the possible damage to a sensor but phones don't have that. Otoh, the lens is small so perhaps the power flux is safe. Not like an f1.7 50mm SLR lens!

 

[Stavros Kiri]

That system may not always be safe for the poor old sensor. A camera with a shutter and mechanical aperture stop will limit the possible damage to a sensor but phones don't have that. Otoh, the lens is small so perhaps the power flux is safe. Not like an f1.7 50mm SLR lens!

I just put the camera in 'Auto'. As far as I know it's safe. I've never seen any damage on any phone with that, and I take pictures with sun on the back or center all the time (& with a variety of phones) ...
This has also been discussed (I think) in an eclipse forum, a while ago.

 

[sophiecentaur]

I just put the camera in 'Auto'.

I don't think that would help because the sensor is not covered by a mechanical shutter. It has to be because the lens is so tiny - a fraction of the power going in, compared with a big camera.
Yep, I remember that solar imaging item. The problem with solar photos is that, for anything other than very basic images, you need a very narrow band Hydrogen Alpha filter which involves an etalon and lots of money. Sunspots are doable though, if you can force a much reduced exposure value.

 

[Stavros Kiri]

I don't think that would help because the sensor is not covered by a mechanical shutter. It has to be because the lens is so tiny - a fraction of the power going in, compared with a big camera.
Yep, I remember that solar imaging item. The problem with solar photos is that, for anything other than very basic images, you need a very narrow band Hydrogen Alpha filter which involves an etalon and lots of money. Sunspots are doable though, if you can force a much reduced exposure value.

(Sorry for the delay in replying) I'm not very familiar how phone cameras and sensors work (you probably know more), just out of practice.
How much of what you say also becomes a problem too though in the original welding helmet idea? ...

 

[sophiecentaur]

How much of what you say also becomes a problem too though in the original welding helmet idea? ...

Clearly it's not a problem cos we can see it working and not for the first time on the video. But the flux density from the arc, viewed from a distance of a few tens of cm will probably be less than the Solar constant, anyway. A bigger risk is to get some molten steel droplet landing on the lens. A glass / plastic screen would probably be a good idea. Those spatters get everywhere - hands, clothes and anything else on the bench.

 

[Stavros Kiri]

Clearly it's not a problem cos we can see it working and not for the first time on the video. But the flux density from the arc, viewed from a distance of a few tens of cm will probably be less than the Solar constant, anyway. A bigger risk is to get some molten steel droplet landing on the lens. A glass / plastic screen would probably be a good idea. Those spatters get everywhere - hands, clothes and anything else on the bench.

It makes sense

 

[anorlunda]

https://www.wired.com/story/smartphones-ukraine-civilian-combatant/

Ay ay ay. I never visualized this one. Below are the plus and minus sides of the same news item.

1. On the positive side, civilians with smart phones can aid their country's forces using smartphone apps. One app, said to be used in Ukraine, looks for images of the enemy. When spotted, it transmits the coordinates back to their country's automated artillery. A salvo of shells could start landing on the enemy in just seconds. That's very lethal. What citizen could resist helping?
2. On the negative side, since almost every citizen carries a smart phone, every citizen may be presumed to be a combatant. The Geneva conventions that say you can kill combatants but not civilians is rendered moot. Mass executions of smart phone owners are no longer a war crimes. OMG, what a horrible result.

In a different, but related case from Ukraine, all soldiers in war zones are strictly forbidden to carry cell phones, but some do anyhow. Policing that rule is impossible. The report is that Ukraine detected Russian soldiers phoning home. They then made their own phone calls to the soldiers' mothers saying, "Do you know what your son is doing?" That sounds very amusing, but it can have lethal consequences in a war zone.

 

[sophiecentaur]

Below are the plus and minus sides of the same news item.

The whole notion of a civilised war is paradoxical. The 'rules' of war have always been crazy - like the initial ban on using crossbows to kill christians, because the injuries were so horrific. Civilians are very vulnerable because they don't make the rules of the time.

 

[Klystron]

The whole notion of a civilised war is paradoxical. The 'rules' of war have always been crazy - like the initial ban on using crossbows to kill christians, because the injuries were so horrific. Civilians are very vulnerable because they don't make the rules of the time.

Concur. The ban on crossbows during warfare refers to publications by Pope Innocent II before his papacy while representing the Catholic church at the Concordat of Worms and later as disputed pope. Crossbow bolts produced injuries consistent with other war weapons at that time but extended the carnage to knights wearing armor.

Cynics and pragmatists argue these weapon bans restricted common soldiers and yeomen using handheld weapons that neutralized prior advantage of expensive body armor. Twelfth century steel crossbows fired bolts tipped with steel 'warheads' that penetrated contemporary armor. Fourteenth century firearms pressed this advantage of the common soldier against armored aristocracy.

Bans on communication devices as civilian weapons appear consistently throughout history, even crazier than attempting to vilify carrying smart phones. Some overeager 19_th C. campaigners in Southwest US and earlier in Mexico tried to capture anyone traveling with a heliograph or mirror fragments as potential spies relaying troop movements to the enemy. WWII bans on radio transmitters and even telescopes/binoculars in civilian hands repeated these strictures.

 

[256bits]

Smart phones replace - other topics of discussion. 184 posts to prove my point.

 

[jedishrfu]

We always forget the brick when you can no longer charge it or it no longer gets updates because its obsolete.

 

[symbolipoint]

We always forget the brick when you can no longer charge it or it no longer gets updates because its obsolete.

Here is not a strictly mathematical relationship but if I spend $100 for a mobile devise, it better last no less than 5 years. If I spend $300 then it better last 13 to 16 years.

 

[jedishrfu]

Five years is about right no matter the price. Mobile technology marches ever forward and your phone just can't keep up.

 

[Hornbein]

Makeup mirror.