I have encountered more image descriptions on Mastodon in 24 hours than I have in Twitter in a couple of years. Seriously. I'm not exaggerating.
As a blind person, this means a lot to me. If you read this and you describe your images, thank you so, so, so much on behalf of all of us. If you don't, now you know you'll be helping random Internet strangers make sense of your posts by typing in a few more words than usual.
@Leftcel_Infilitrator Thanks for asking! Pinafore seems to just give you an edit field to type in a description when you upload any kind of media, but I am not sure how other clients do this.
@Leftcel_Infilitrator The fact that people constantly have to ask this shows that Mastodon hides this feature way too much, and it sucks. 
Once you upload an image, you should see an "edit" button. Edit what? The image size? Nope, edit the image description. Good labeling, huh?
Thank you for asking and wanting to make the internet a more accessible place. 
@guilevi
@Mayana @Leftcel_Infilitrator @guilevi Wow, I didn't know that! I will add descriptions from now on. Thanks for sharing this.
@guilevi @Leftcel_Infilitrator @Mayana honestly, the button should say describe media. It is also used for adding caption like text to videos which is why I did not say describe image
@Leftcel_Infilitrator @guilevi
Yup, upload and click Edit It should be far more obvious or popup a text field when an image is uploaded
@defrisselle @Leftcel_Infilitrator This is an example of an awesome image description. Thank you!
@guilevi @Leftcel_Infilitrator
There is also an OCR feature to identify text in images Didn't know about that Didn't pick up any of the text
long-ish (~1400 chars) post about hashtags on Mastodon, and accessibility.
@Leftcel_Infilitrator while @guilevi has already answered your question about how to describe images, I'd like to add some information about hashtags. :)
Hashtags on Mastodon are primarily used for content discovery. Most servers/instances only allow you to search for toots by hashtags as search for any text in the message (often referred to as 'full-text search') is resource intensive.
So, if you want people to find your messages while searching for a specific topic, having the right hashtags in your message is often the only way. Not just for finding other people's messages, but also finding back an earlier status you posted yourself.
What can help people with screenreaders when it comes to hashtags, is to capitalise ever word in compound hashtags; also referred to as camel-casing. For instance, rather than #accessibilitytips, write #AccessibilityTips, as some (most?) screenreaders will use that as a word-boundary hint, and thus allow them to pronounce the hashtag as individual words.
Whether to use inline hashtags, replacing the actual word, or to list them all at the bottom of your post, is a personal preference from what I understood.
If you use a lot of hashtags, I assume a summary at the end rather than inline is probably better, but since I don't use a screenreader myself, I'll defer to the expertise of those that actually do use them.
long-ish (~1400 chars) post about hashtags on Mastodon, and accessibility.
@FiXato @Leftcel_Infilitrator @guilevi You can also follow feeds of hashtags via rss fyi.
@Tepid_Tapir What makes you think so?
@Tepid_Tapir That wouldn't be very helpful, no. Hopefully you can consider giving a little more detail in the future, now that you know. :)
@Tepid_Tapir There's quite a lot of us, yeah. Most of the folks on this instance, for example.
Why do you think so? It's honestly not as complicated as some folks make it out to be. Even simple descriptions are miles better than nothing.
Consider what message you're trying to send with the image -- is it a cute doggo? A meme' A beautiful flower? -- and try to convey at least a little of that through the text. I'm sure you'll do fine. And if that's too complicated, an objective description like "a black dog with a ball in its mouth" works, too.
@guilevi
@guilevi Thanks for mentioning this. I have never thought about it how important picture descriptions can be.
I will take care about that in the future for everything I publish.
@guilevi Yes yes yes! Image descriptions are a blessing!
I've described every image on my account, and Image descriptions are required by rule on RaRu.Re !!
@guilevi What sort of stuff makes a good description? Similarly, what should be avoided when writing image descriptions?
I do my best to describe everyhing I upload but I'm constantly worried there's things I'll type that screen readers or braille displays won't pick up on.
@pyredrid Thanks for the question! I don't think there are any implicit guidelines or rules for writing descriptions. I'd say just say what you think should be said. If the point of the image requires just a few words to come across, use a few words. If the details are important to you or to the post, write as much as you like.
@pyredrid I can send examples later if required, but for now here's a short explanation:
When writing a description, consider what message your image is trying to convey. If you're posting a pic of the amazing cake you made, you'll obviously want to focus on what type of cake is it and how tasty it looks, rather than the bit of wall you accidentally captured in the background. With a painting, you'd focus on its contents, mentioning the type of paint used only briefly -- unless the paint and style were the focus. So on.
Don't be afraid to be less than objective. You aren't writing these descriptions for newspapers. The Fediverse is humans interacting with humans. Trust me, we not only don't mind, but genuinely want to read about how cute that thing your pet does is. 
But if objective descriptions are more your thing, those obviously work well, too. Write what you know and enjoy.
@guilevi
1/2
@pyredrid There are lots of good guidelines on image description. Here's one https://mobile.twitter.com/robothugscomic/status/949324465191694337
Here's another https://www.perkinselearning.org/technology/blog/how-write-alt-text-and-image-descriptions-visually-impaired
Almost any text you write will be "picked up" by screenreaders but if you're worried about something you can always try activating the one that almost definitely comes standard on your phone/tablet/laptop/etc.
@guilevi
@guilevi MISSION ACCOMPLISHED.
Seriously, I get a kick out of sneaking in extra info or carefully worded humour and puns in there. I know many others do.
A lot of my images are from the nearby national park. Do visual descriptions of lakes and trees make much sense to you? How do you perceive nature?
@dch They make perfect sense! I really appreciate carefully worded descriptions, especially if, like you said, they try to be somewhat humorous while still carrying meaningful information.
TO some extent, I think we make up our own abstract concepts of vision-centric terms, sometimes as plain relationships to other terms. I don't have much time now, but I'd definitely be up for talking about this at some point if you're interested.
@guilevi I admit 1 in 10 times or so I get lazy about it because I had never knowingly seen anyone on here who used them, but seeing this has kicked my ass into gear and I'll be sure to always do so! Thanks for the reminder!
@hammerhead I love reading posts like this one. Thank you!
@guilevi In addition, people can follow @PleaseCaption (and let the bot follow them back) to get a reminder if they post an image without description.
@guilevi please if I forgot to do so remind it to me
@_Christ_OFF_ Perhaps this bot would help with that? @PleaseCaption
@guilevi
Hi.
Actually I don't put description on the images I toot there, usually because they're just funny ones and it stops being funny if it has to be described/explained so the extra work seems pointless to me.
Would you consider that acceptable ? When do you believe it is important to describe images ?
@lienrag We Blinds from the planet of Blindus indeed to not understand and appreciate humanity's fondness for these illogical things you call "jokes". 
But jokes aside, we love funny things just as much as anyone else. Well ... most of us, at any rate. So if you can think of any way of passing along at least some of the joke's humor into the description, that would be very appreciated.
If you can't think of how to do that, you could try tagging @imagecaptionspls . Plenty of people there are excellent at this kind of thing and would be glad to help.
But in general, just remember that just because a joke loses all its fune *to you* if it is explained, that does not mean others will all feel the same. We've gotten used to finding descriptions of visual jokes sufficiently amusing; that's all we get, after all. 
@guilevi
@lienrag I'm not blind or visually impaired but as a neuro-atypical folk, or just occasional user, I found image descriptions incredibly useful to actually get the joke
descriptions in images are very important and useful for a lot of people
sometime, I lack the energy/spoons to add them, but every time I can do it, I take the time, because you never know when someone in your TL will need it
@Mayana @lienrag @imagecaptionspls @guilevi Attempting https://chaos.social/@MissInformation/106211805683723049 as an example:
Meme: "A moment of tension in the Vatican. If the bishop moves forward the queen can take him."
The Queen of England and a clergymember are standing on black squares of a checkerboard-patterned floor, like a chess queen and a chess bishop placed on squares of a chessboard. If the bishop moves forward a diagonal square, they'll land on a diagonal with the queen, who can then capture them.
- Packbat 🎒
@packbat @Mayana @imagecaptionspls @guilevi
Yeah, sorry, no way I go from sharing a funny image in 5 seconds and two clicks to a full-fledged description like the (very good) one you provided.
Not on unpaid time.
@lienrag Doing something nice for others does indeed require some non-zero amount of effort. Kindness and convenience seldom collide, and that is a good lesson to know.
So very many of the things you yourself enjoy were made with time just as unpaid as yours. Most of Wikipedia and plenty of other wikis out there, most open source software, a lot of educational content, vast quantities of art ...
I will not make an attempt to change your mind. But I am incredibly thankful that the people working on those do not feel the same about much more difficult tasks that you do about spending, at worst, a couple minutes.
@packbat @imagecaptionspls @guilevi
Feel free to add such caption to each of my post containing a picture, I certainly won't mind.
@lienrag I will assume that this comment is directed towards me and politely inform you that I am just as blind as @guilevi is. That might make this task you expect of me rather difficult ...
There is, of course, @imagecaptionspls , through which I assume @packbat was summoned. But while they are quite quick to help people who truly -- usually due to being neurodivergent -- aren't able to write descriptions themselves, you have so far given no indication of this being the case. They're good folks, but only human. Your laziness might make them less willing to help out. But it is their choice to make.
Actually this was a general comment but yes, I understand how it can be hurtful to you. My apologies then.
@lienrag 1. @Mayana happens to be blind, so this is another thoughtless comment by you.
2. No need to worry about image description. I don't know about other blind fedizens, but I certainly no longer have an interest in what you post. No, not because you don't describe your images or because you refuse to describe them (there can be very legitimate reasons for both of these things), but because of how you do both of these things.
@packbat @imagecaptionspls
@Mayana @lienrag @imagecaptionspls @guilevi ...I have to admit, I spent twenty minutes on that. I had a description /at all/ way faster than that, but I wanted a really good and snappy one - and it's not my joke, so I didn't already know how to structure it.
- 🎒
@packbat Then you're even more awesome than I thought. You really shouldn't have wasted this much effort on this. Hell, perhaps an example of quick and easy description would've even been more encouraging; but probably not. Probably nothing would help.
Thank you for trying, still. 
@lienrag @imagecaptionspls @guilevi
@Mayana @packbat Hard agree with this entire toot. :)
@lienrag @imagecaptionspls
@guilevi @Mayana Thanks, y'all.
...frankly, this kind of challenge is fun for us - that's a big part of why we follow @imagecaptionspls - and the "but it stops being funny!" argument is made /so/ often that we didn't want to let it stand without an attempt at a concrete counterexample. So, this particular time it was worth it to us; next time, it probably won't be and we won't bother.
- 🎒
@Mayana @imagecaptionspls @packbat @lienrag That's okay. I do hope you never have an issue that prevents you from accessing content the normal way, though, because there is always going to be this one person within the crowd who will make a tactless comment without any kind of human decency. That's you, buddy. Please don't expect anyone to do anything to help you after they read this post. I never intended to feel like I was demanding or forcing anyone to spend precious time to make the Internet more accessible. Thank god you're the minority. Thanks :)
You were not demanding nor forcing anyone, no, at least that is not how I understood any of your posts.
I may take from your first message some incitation to post a description on images in important messages, or maybe even add a short description if I create an image myself, but no I will not take 20 minutes for a meme.
@lienrag @guilevi Excuse you, that meme was amazing and whoever originally created it had to do some careful cropping and photoshopping to make it work.
Also it doesn't /have/ to take twenty minutes. https://mamot.fr/@nizarus/106144731219852873 shows a bunch of troops goose-stepping in the background and a bird taking a similar step in the foreground.
That took two minutes and half of that was looking for the original tweet and trying to figure out whether "goose-stepping" was the correct term.
- 🎒
@guilevi How do I describe my images. Do I use the hashtags?