Note that both very high or very low aperture settings also bring their own optical issues. At very low values (big hole) you’re getting hurt by different aberrations (essentially too many paths the same rays can take to the sensor) and at very high values you’re getting hurt by diffraction. At the low end, it’s good to go a little higher than the lens advertises, and at the high end anything over F13-F18 (depending on the gear) is usually quite bad.
To be a little more precise, f is not a camera-specific constant. It's the focal length of the lens. It's a formula that tells you the diameter of the entrance pupil. So at a focal length of 50mm, an aperture value of f/2 means an entrance pupil diameter of 25mm.
But photographers generally just say "f2", meaning an aperture value of two set on the dial of the camera/lens. It's one stop faster (twice as much light) as f/2.8. It'll give you a relatively shallow depth of field, but not as shallow as e.g. f/1.4.
> For just over five weeks, from February 7 to March 14, visitors will be allowed to climb the towering 20-foot scaffold inside the castle’s Sala delle Asse to view conservators at work on Leonardo’s mural, after which it will be sealed off again for another 18 months, making this limited public access a rare opportunity to see it up close mid-restoration.
From the last sentence - it's a chance to see it mid-restoration. But will it be publicly accessible after 18 months?
Usually discord ignores all issues related to invisibility leaks but responds very fast to other types of issues which is why i decided not to wait for weeks for a fix, instead publish it and watch it get fixed.
As much as I appreciate the tiny serif for lowercase L and numeral 1 to differentiate l I and 1, I am not the biggest fan of the capital I glyph without the horizontal serifs. It's my biggest design gripe with most sans-serif fonts as it makes it FRUSTRATINGLY difficult to differentiate when looking at words by themselves.
Is that lota or Iota? Is that iodestone or lodestone? Both real examples where I fumbled reading them -- once in front of a class :)
This is why my favorite sans-serif typeface has been (and will always be) IBM Plex Sans [1]. It's an open font [2]. I have all my laptops and desktops set to using the IBM Plex typefaces, including browser overrides. If only there were a way to do it system-wide on my Android phone...
Marissa Mayer on why Google chose sans-serif fonts for search results:
When I had to make a decision about should the Google results pages be serif or sans-serif, I didn't have enough users to do the split A/B testing and mathematically figure that out, so I ended up reading a lot of research and ultimately finding out that serif fonts are more readable, and sans-serif fonts are more legible.
The serifs create a horizontal rule that guides the eye, so serif fonts are much better when you’re reading long pieces of text. Sans-serif fonts are more legible which means that... when the serifs are removed your eye can spot read a character much better and much more quickly, and as a result it is much better for spot reading. In an activity like search it turns out you want to facilitate spot reading to a much greater degree than reading long prose.
IBM Plex is very good. Recently, I have been enjoying https://rsms.me/inter/ for interfaces a bit more (with ss02 for body and ss02+tnum for tables activated).
Inter is the only libre typeface that has good coverage, and produces readable small text on terrible 80 DPI displays. I've tested probably hundreds of them.
I guess I can try to argue that it if it weren't as generally useful as Helvetica it wouldn't have been made the default in Figma and it wouldn't be, well, so generally used.
Hah, this one can go on Wikipedia as an example for "chicken or the egg"! IMO, there's probably a number of other fonts that could've been chosen rather than Inter as default Figma font, and if they had been, they'd now be more ubiquitous than Inter. Of course, we'll never know. Unless someone here is looking to do a research study into popularity of fonts over time compared to popularity of Figma and seeing how strong the correlation is - maybe a weekend project for someone into typography ;)
Ah, it initially appeared that the capital I and the lowercase L have identical-looking glyphs. But scrolling down, I see the ss02 and tnum features add noticeable glyphs. Looks like a nice typeface.
I really enjoyed reading through [1] as it gives a lot of insight into what goes into making a font. However I wonder what incentives does IBM have for putting this much work into making it public, accessible and widely used. Wouldn't the ubiquity of the font make it less strong for their brand identity?
That's why I love the Readex Pro font. It also has glyphs for Arabic and a lot more languages in the same file, so I can use one font file for everything.
I agree with other comments that this research treads a fine, unethical line. Did the authors responsibly disclose this, as is often done in the security research community? I cannot find any mention of it in the paper. The researchers seem to be involved in security-related research (first author is doing a PhD, last author holds a PhD).
At least arxiv could have run the cleaner [1] before the print of this pre-print (lol). If there was no disclosure, then I think this pre-print becomes unethical to put up.
> leading to the identification of nearly 1,200 images containing sensitive metadata. The types of data represented vary significantly. While device information (e.g., the camera used) or software details (such as the exact version of Photoshop) may already raise concerns, in over 600 cases the metadata contained GPS coordinates, potentially revealing the precise location where a photo was taken. In some instances, this could expose a researcher’s home address (when tied to a profile picture) or the location of research facilities (when images capture experimental equipment)
Having arXiv run the cleaner automatically would definitely be cool. Although I've found it non-trivial to get working consistently for my own papers. That said, it would be nice if this was at least an option.
Leaks of read/write access to documents and GitHub, Dropbox etc credentials is certainly worrying, but location and author/photographer details in photo metadata? That's quite a stretch, and seems like the authors here are just trying to boost the numbers.
The vast majority (I would wager >(100 - 1e-4)) of location of research institutions is public knowledge and can be found out by simply googling the institution address (I am not aware of a single research institution that publishes publically where the location is confidential).
They responsibly disclosed it in their research paper. An unethical use would be to use those coordinates to gain state secrets about say, research facilities
This is a wonderful write-up and a very enjoyable read. Although my knowledge about systems programming on ARM is limited, I know that it isn't easy to read hardware-based time counters; at the very least, it's not as simple as the x86 rdtsc [1]. This is probably why the author writes:
> This code is more complicated than what I expected to see. I was thinking it would just be a simple register read. Instead, it has to write a 1 to the register, and then delay for a while, and then read back the same register. There was also a very noticeable FIXME in the comment for the function, which definitely raised a red flag in my mind.
Regardless, this was a very nice read and I'm glad they got down to the issue and the problem fixed.
Bear in mind that the blog post is about a 32 bit SoC that's over a decade old, and the timer it is reading is specific to that CPU implementation. In the intervening time both timers and performance counters have been architecturally standardised, so on a modern CPU there is a register roughly equivalent to the one x86 rdtsc uses and which you can just read; and kernels can use the generic timer code for timers and don't need to have board specific functions to do it.
But yeah, nice writeup of the kinds of problem you can run into in embedded systems programming.
> This was in snapshots for more than 2 months, and only spotted one other program depending on the behaviour (and that test program did not observe that it was therefore depending in incorrect behaviour!!)
Fascinating. I wonder what that program is, and why it depends on the NUL character.
I'm interested to see how the roll turns out - gave it for development the other day, had a good laugh with the employees though.
I now have a mnemonic for it: Blor - a (somewhat) portmanteau of Blur and low. So low aperture = blur.
Edit for clarification: I mean low number (2 vs 32) = blur
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