## PayPal increases crypto limit

The acceptance of cryptocurrency into the PayPal platform was one of the reasons for the major bull market that we saw towards the end of last year, as there were many people that had a lot more confidence in the coins since it was being backed by a major payment giant. However, in a recent news article it seems that the PayPal has moved to increase the limit on crypto purchases through their platform, which was a concern for many users. The limit has not been increased to users being able…

## optics – How do I calculate f/stop change for teleconverter that increases lens magnification?

The job of the camera lens is to project an image of the outside world onto the surface of film or digital sensor. The image size of object (magnification) is determined by the actual size of the object intertwined with distance from the camera and the focal length of the camera lens used. If you increase the focal length of the camera lens, the projection distance is also increased. This results and image that displays greater magnification. As an example, if you increase the distance screen to projector of a slide or movie projector and re-focus, the image projected on the screen is enlarged.

Peter Barlow, English Mathematician / Optician, invented an achromatic (without color error) supplemental lens that increased the magnification of telescopes in 1833. The Barlow lens design is the one used in modern teleconverters.

Such supplemental lenses increase the versatility of our camera lens. Commonly they double or nearly double the focal length. A 2X teleconverter doubles the focal length granting a 2X focal length increase which results in 2X grater magnification.

This increased magnification comes with a price. Along with the increased image size comes a reduction in the intensity of projected image. To calculate the impact of this magnification gain on image brightness, we square the magnification gain. Thus for a 2X teleconverter the math is 2 X 2 = 4. We find the reciprocal of this reduction factor by annexing 1/ before the number. Thus, a reduction factor of 4 tells us that the amount of light reaching film or image chip is ¼ or 25% of the former.

Now the f-number system we use is based on an incremental change of 2. In other words, each f-number change doubles or halves the exposing energy. Thus, we divide the magnification increase granted by the teleconverter by 2 to find out how many f-stops reduction results. In this case, a 2X doubling of the magnification results in a reduction factor of 2 X 2 = 4. This value, divided by 2 = 2. This tells us that the functioning f-number is 2 f-stops so we open up 2 f-stops. Go left on the below f-number set.

The f-number set:
1 – 1.4 – 2 – 2.8 – 4 – 5.6 – 8 – 11 – 16 – 22

Thus if the f-number is f/8 and we add a 2X teleconverter, the working f-number changes two f-stope to f/4. Also note – the f-number set is its neighbor multiplied going right by the square root of 2 = 1.4.

Let me that that understanding the resulting reduction factor holds for figuring out exposure when adding filters (filter factor). This value is a multiplier used to manipulate exposure time. Thus if the factor is 4, we can multiply the exposure time by this factor to calculate a compensating exposure time.

Suppose the exposure without filter or teleconverter is 1/400 of a second at f/8. We mount a filter of teleconverter with a factor of 4.

The revised exposure time is 4/1 X 1/400 = 4/400 = 1/100 the revised shutter time @ f/8
Or 1/400 second @ f/4

## multivariable calculus – What do you call a function that’s orientation direction goes back and forth as t increases?

Say I have a function, and say that as I increase t, the orientation of the function changes. What would you call this kind of function?

An example of this would be say;

x^2 + (y+1)/2 = 1

Where x = sin(t), and y = cos(2t)

Image of Curve

As you increase t in this function, the orientation will change, going back and forth in an infinite loop.

i.e. t = (n*π)/2 (as n –> ∞) will give points oscillating between (-1, -1) and (1, -1), what would I call this type of function? Is their a given name for something like this.

## optics – Calculating f/stop chance for teleconverter that increases lens size

I’m trying to calculate the f/stop change of attaching a x2 teleconverter to a 80mm f/2.8 lens. In this instance, the teleconverter attaches to the end of the lens, and has a larger opening than the original 80mm lens.

The original lens would have a lens diameter 80mm/2.8 which is about 30mm.

the new lens seems to be about 40mm, and it’s a x2 teleconverter, so the new f/stop should be 160mm / 40mm = 4.

All the documentation i found suggested that this is wrong and since it’s a x2 teleconverter the f/stop should also be doubled.

where’s my mistake here?

## ❕NEWS – Gas token increases by 300% in the last 24 hours | NewProxyLists

This can be explained since each Ethereum network transaction requires a certain amount of Gas.
This could therefore increase the value of the gas cost. Obviously using the Gas Token, there would be less commission costs, this has led people to invest more in Gas Token recently.
But in my opinion, no worries about other cryptocurrencies, Bitcoin at the forefront.

## dnd 5e – Is there any magic item that increases Hit Points?

Ioun Stone of Fortitude (very rare) DMG p 176 increases your Con score by 2, so would give you 1 extra hp per level.

Manual of Bodily Health (very rare) DMG p 180 increases your Con score by 2, so would give you 1 extra hp per level.

Belt of Dwarvenkind (very rare) DMG p 155 increases your Con score by 2, so would give you 1 extra hp per level.

Amulet of Health (rare) DMG p 150 sets your Con score to 19. As you have 15 that would be 2 extra hp per level.

Gloves of Soul catching (legendary) Candlekeep Mysteries p 169 sets your Con score to 20. As you have 15, that would be 3 extra hp per level.

Do note that items that set your Con score to a flat value do not stack with other items that increase your con score.

There are also 5 items in the DMG that allow you to cast Wish and you could wish for an increase in constitution score. Namely: Luck Blade, Ring of Three Wishes, (Eye of Vecna + Hand of Vecna), Deck of Many Things (risky), Efreety Bottle (risky)

Why I think Wish would work: I know at least of one official campaign where a riddle has an ability score increase as a possible reward and wish as a less likely one. So the ability score increase is seen as the less powerful of the rewards. To me that is at least an indication that wish could grant an ability score increase.
Specifically here:

ToA area 70, 1d4+1 int increase on a 91-99, wish on a 100

Berserkers Axe (rare) DMG p 155 gives you a flat 1 hp per level. But it does come with a downside.

Some items also allow you to cast a spell that can grant you temp hp. But that would not be a permanent increase of health.

## Is there any magic item that increases health?

My character has the lowest health in our party (I mean he is even lower than the Artificer of the party I am a Fighter) so I was wondering if there was any magic items that increase max health. I am more so looking for one that increases this health permenantly.

## dnd 3.5e – Alter Size Salient Divine Ability referring to Improving Monsters Size Increases?

The Alter Size Salient Divine Ability states

As a free action, the deity can assume any size from Fine to Colossal. The deity also can change the size of up to 100 pounds of objects it touches. If the deity has a familiar, personal mount, or personal intelligent weapon, the creature can change size with the deity if the deity touches it, but its weight counts against the deity’s weight limit. This is a supernatural ability.

Notes
This ability allows the deity to assume any proportions from the size of a grain of sand up or as much as 1,600 feet tall. A radical change in size can have great impact on the deity’s combat ability. The deity’s Strength, Armor Class, attack bonus, and damage dealt with weapons changes according to the size the deity assumes. The deity’s Strength score can never be reduced to less than 1 through this ability. Also note that use of this divine ability does not affect all the deities’ characteristics.

https://www.d20srd.org/srd/divine/divineAbilitiesFeats.htm#alterSize

Do the adjustments mentioned refer to the size adjustments for improving monsters table?

https://www.d20srd.org/srd/improvingMonsters.htm#sizeIncreases

The text of Alter Size states ‘The deity’s Strength, Armor Class, attack bonus, and damage dealt with weapons changes according to the size the deity assumes.‘ and ‘Also note that use of this divine ability does not affect all the deities’ characteristics.

So referring to the size increase table is it correct to assume the only adjustments made when considering that table are taken from the Strength column and AC / Attack column AND NOT any adjustment from the Dex, Con, Natural Armor columns?

The reason I ask is I’m currently in the process of 3.5-ising Nyarlathotep from CoC D20 and need to get it correct as an epic threat for my players.

## pathfinder 1e – Are there any size increases that don’t reduce Dexterity?

I have a character who is interested in increasing their size, but relies on Dexterity and so does not want to take penalties to that in the process. Are there any options for doing so? Shapechanging is generally out, because I need to keep the attributes of my own form.

The character in question has 10 levels of the ninja class from Complete Adventurer, using the water ninja variant class features from Dragon vol. 354. Since 10 levels are dedicated to this class, this limits other options. Righteous might is the one option I’m aware of with no Dexterity penalty, but a 10th-level ninja/9th-level cleric seems like a painful combination to me, and 19th level is a long way to wait for just one size increase.

The other option is mountain rage, which also has no penalty. However, since you have to be a goliath to get it, and they do have a penalty to Dexterity, that doesn’t help very much. Arguably, ferocity could counteract that, and there is technically the option of the stoneblessed prestige class from Races of Stone to count as a goliath, but stoneblessed is three levels of nearly-nothing for the privilege, and while ferocity might be good if I’m investing in it I’d want to keep all of that bonus.

Finally, since for a moment I thought it might, let me note that half-minotaur doesn’t work here: while it doesn’t apply a Dexterity penalty in its Abilities rules, the Size and Type rules tell you to “See Table 4–2: Changes to Statistics by Size in the Monster Manual for changes to the base creature when it gains a size category. The changes in this template are in addition to the changes outlined there.” Table 4–2 would be this one, and it does apply a Dexterity penalty for almost-all size increases (unless I’m already Huge, which is not a size I expect to reach ever, and certainly not at 1st level). Most player-available size changes don’t use those rules (those were initially just for size changes when advancing monsters), which gives us some hope, but half-minotaur specifically invokes them.

Effects that grant Strength bonuses are acceptable, but most Strength bonuses are costly, so expensive options whose value is supposed to come from a Strength bonus are not great. What I’d really, really like to see is some option that allows me to swap the Strength bonus to Dexterity, or barring that, something that just says “You don’t take Dexterity penalties for increasing your size,” which would enable me to seek any size bonus I want here.

Any 3.5e content (including 3.5e-legal 3.0e content) that is published by Wizards of the Coast or in Dragon or Dungeon magazine, as well as Pathfinder content produced by Paizo, is acceptable, with the exceptions of epic and/or mythic material, and anything with a level adjustment greater than +1 (and even a +1 is something I’d really like to avoid). Please note sources, and also note if there is a conflict between 3.5e and Pathfinder on a given option—for instance, Pathfinder-style shapechanging might work, but that conflicts with 3.5e. We’re generally favoring 3.5e here, but a case can be made for specific Pathfinder items ported.

## MongoDB latency decreases as throughput increases

I am trying to benchmark MongoDB and obtain a throughput vs. latency plot. I am using YCSB as the client and I increase the number of client threads to increase the load on the database. I consistently obtain a plot such as below.

The average latency of a request first decreases as I increase the number of client threads (and thus the throughput), as opposed to increasing monotonically with throughput. I am trying to figure out the reason behind this.

MongoDB runs on 8 CPUs and I have observed this behaviour on different machines. I use the official docker for MongoDB but the behaviour is the same with bare-metal.