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Finding Images on Flickr

Last updated: 13 July 2009
Published in: Finding and using digital media
Tags: business & community engagement | finding images | flickr | photo sharing | photographs

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Summary

This document looks at the pros and cons of using the photo sharing site Flickr as a source of images.

Introduction
Using images you find on Flickr
Quantity vs quality
Signing up to Flickr
Basic searching
Sorting your search results
Group pools
The Commons: images with no known copyright restrictions
Date searching
Finding images using maps
Finding photos taken by specific camera models
Favourites - returning to images you’ve saved
Making contacts
Sharing non-public images
Comments, notes and discussions
Subscribing to photo feeds
Other ways of finding Flickr images
Further resources

Introduction

Since launching in 2004, Flickr has become a well-established and incredibly popular photo sharing site.

As at June 2009 Flickr had over 35 million members around the world who between them use the site to store over 3.5 billion photos.

Photo by tochis on Flickr - used under a Creative Commons licence

Last year Flickr introduced video to the site, allowing users to upload clips of 90 seconds or less. This document is primarily about using Flickr to find still images, but much of what we say here also applies to video clips.

Those who put their photos on Flickr do so for a variety of reasons, including:

As a photoblog to record their daily lives
As a means of sharing photos with family, friends, colleagues or the wider world
To seek feedback on their photos from others
To store and organise their image files

Some users are established or up-and-coming photographers who use Flickr as an additional means of publicising their work. Others will have joined to become part of an online community where they can meet like-minded people to share photos and ideas with. Increasingly, public institutions such as universities, museums and archives are using Flickr to bring attention to their collections.

Whatever their reasons for joining and sharing photos, Flickr members have made available a rich source of imagery that should not be ignored when you are looking for pictures.

The staggering numbers alone make Flickr a good place to start - almost every conceivable subject has been photographed and uploaded to Flickr. Most images are recently-taken digital photos, but a large number of users upload scans of older negatives and prints.

That’s not to say it’s always easy to find the right image - indeed it would be misleading if we didn’t highlight upfront that much of what you come across on Flickr will make you wonder what on earth it’s doing there (or why anyone thought it would be a good idea to take the picture in the first place).

Quantity certainly does not equate to quality here, but there are more reasons than sheer numbers that make Flickr a useful starting point when sourcing pictures. This document is intended to highlight the best ways to find images to use for educational activities including teaching, research and business and community engagement (BCE), while pointing out some of the pitfalls you can avoid.

A friendly word of warning: Once you start looking for images, it’s easy to spend longer than you planned. As soon as you find an interesting photo, you may find yourself tempted to look at other photos in the user’s ‘Photostream’, start reading comments, following links, clicking on interesting sounding tags, dipping into group pools, leaving comments, subscribing to RSS feeds, etc. Often this serendipitous approach will lead you to the exact photo you had in mind - one you may not otherwise have come across. Indeed, as this document goes on to describe, these are some of the best ways of finding images, but be warned: on your first few visits they may also lead you off on distracting tangents!

Using images you find on Flickr

Before we look at the best ways of finding images, we should highlight some important issues you need to consider regardless of the way in which you plan to use the images.

The most useful licence you’ll come across on Flickr is ‘No known copyright restrictions’, which allows you to use certain images free of charge for any purpose. These images are collected together in The Commons - more of which below.

Where this is the case you should not use the photo without seeking permission from the photographer. Be aware that the Flickr member who uploaded the image may not necessarily be the photographer or rights owner - indeed, they could have obtained the image from anywhere. If you plan to use images in any way, make sure you read the rights associated with the image and seek permission from the photographer.

Photo by johnb/uk on Flickr - used under a Creative Commons licence

Thankfully, many users choose to change the default licence setting and offer some or all of their photos under one of the six Creative Commons licences. By doing this they are allowing others to use their images according to the simple-to-understand terms of the licence.

Flickr provides an easy way to filter search results to only include images with Creative Commons licences - either by using the options in the Advanced Search, or by browsing through recent images uploaded under each type of licence.

Note that just because a photo has a Creative Commons licence, it does not necessarily make it alright to go ahead and use it without first asking yourself a few questions:

Does it look like the photo belongs to the user? Remember, they could have found the photo elsewhere, so it’s always wise to look at other photos in their photostream to see if it looks like the sort of image the user would produce; read the caption and check the tags
Are there people in the picture? Unless the photographer explictly states that the photo is model released, you may need permission from people in the photo if they are identifiable
Could the way in which you plan to use the image be seen as controversial? Ask yourself whether the photographer or any people in the picture might be upset or offended by the context in which you are using their work - see also moral rights

If you are in any doubt, always contact the Flickr user for more information.

Creative Commons licences are non-revocable, so if you obtain an image whilst it is under a Creative Commons licence, you may use the work according to that licence. It is possible for owners to change the licence on an image at any time, so you may find that an image that used to have a Creative Commons licence has been changed to ‘All rights reserved’. So long as you obtained it with the Creative Commons licence you can still use it, but it’s important to be aware that the owner may not know this and in these cases it’s always best to contact them for confirmation of usage terms.

In order to contact Flickr members, you’ll need to be signed up as a Flickr user yourself (see Signing up to Flickr below), though some photographers may provide contact information or terms of use in their user profile. As the Flickr FAQ states: “When you contact a photographer, it’s best to include as much info as possible about the photo, yourself, and how you want to use the photo.”

Once you find an image you want to use - and you’ve established that it’s OK to use it in the way you want - you’ll probably want the best quality version available. Most photos have an ‘All sizes’ link (just above the photo and beneath the title). Clicking this will show the sizes available for download.

It’s down to the photographer to decide whether they’re going to provide the original for download. They may choose to upload only a small version, or to restrict downloads to signed-in users, contacts or family and friends. In these cases there will be no link to ‘All sizes’, but you may find after contacting the photographer that they are willing to supply a larger version.

Be aware too that users can remove their images from Flickr whenever they like, or they can make them publicly unavailable - this could cause problems if you are relying on a particular image being available indefinitely.

Quantity vs quality

Let’s return to those numbers. Depending on the time of day, up to 10,000 images are uploaded every minute! That equates to over one million photos per day.

Photo by austinevan on Flickr - used under a Creative Commons licence

As previously mentioned, with so many new pictures appearing by the second you will find that the quality varies enormously. Many users post images unedited straight from their cameras (or increasingly from their phones and other mobile devices). A high proportion will be people’s holiday photos, snaps of family and friends, and wedding pictures. Some of the most popular ‘tags’ (keywords) added to images include: beach, family, party and wedding.

Those are the images that people have bothered to add tags to - many images are not captioned at all: as well as having no tags, a large number have no description, or no title other than a default image file number (e.g. DSC_1968, img087, etc).

A search on ‘the’ (one word that is more likely to be used in an English language description than any other) brought up over 100 million hits. Even taking into account the number of images described in languages other than English, this figure indicates a large proportion of the 3.5 billion total are uncaptioned.

According to company data cited by Reuters in 2007, around 45% of Flickr users are located in the United States (some of whom will not be English speakers). Of the remaining 55%, the next two countries in terms of users are Britain and Canada, followed by Germany, Brazil, Spain, France and Australia.

So even though billions of pictures are available on Flickr, many will remain irretrievable simply because there’s little or no accompanying information to search on. Furthermore, many users choose to keep their photos private so they are not publicly searchable.

Of those images that are retrievable, it can still be a headache sorting the wheat from the chaff and the following sections should go some way to helping you do just that.

Signing up to Flickr

As Flickr is part of Yahoo, anyone wishing to sign up to Flickr is required to first sign up for a free Yahoo ID. If you already have a Yahoo ID, you can use that on Flickr.

The basic Flickr account is free of charge, but there is also a Pro account ($25 annual subscription) which you may find useful if you plan to use Flickr to organise your own images. Note that you can only get rid of the adverts if you have a Pro account - see our Using Flickr to Organise a Collection of Images for more on the differences between the free and Pro accounts.

There’s nothing to stop you searching Flickr without an account, but there are several advantages to signing up for a free account even if you don’t plan to upload photos yourself.

Firstly, you’ll be able to mark images as favourites (see Favourites - returning to images you’ve saved below)
You’ll need to sign up if you want to contact other users about using their photos, as only members of Flickr can send messages to one another
Only signed-in users can leave comments, add notes and tags, join groups
If you want you can share an account with colleagues - two of us were able to log into the same account and add/remove favourites at the same time - this could be useful for collaborative work
Advanced search options are slightly different if you’re not signed in. Signed-in users can choose levels of ‘safety’ (e.g. SafeSearch On/Moderate/Off). Non-members don’t get these options and SafeSearch is always switched on, which may limit your search results

Note that even with SafeSearch on, images that some people may find offensive will not necessarily be filtered out - it is up to users to flag their own material as Safe (“Photos are suitable for a global, public audience”), Moderate (“Some of the things you upload may be considered offensive by some people”), or Restricted (“Your photostream is unsuitable for children, your grandmother or your workmates”) and not all users will flag their material correctly.

Some fairly ‘unsuitable’ images were being uploaded as we browsed the site with SafeSearch on. These images were newly uploaded and did not necessarily stay ‘Safe’ for long - if the uploader themselves does not adjust the photo’s safety level, other signed-in users can ‘flag’ a photo, marking it for review by Flickr staff. If enough other members flag the photo, Flickr will hide it from the main public pages or remove it altogether if it breaches Flickr’s Community Guidelines.

Basic searching

The default search returns images from everyone’s public photos. You can choose to search Full Text or Tags Only. Searching Tags Only may generate more relevant hits, but remember: not all users bother adding tags to their photos and just use the title and/or description fields - a Tags Only search will ignore these fields. Always think carefully about the terms you use and try both types of search.

Once you are viewing an image by a particular user, you can see all the other photos in their Photostream by clicking on their username or the picture next to their name (their Buddy icon).

You can click on the tags next to anyone’s photos to see other images they have with that tag, or to view everyone’s photos with that tag.

Note that there is no ‘controlled vocabulary’ for tags - a user can add any tag they deem fit to describe an image. Users may misspell the tags they add to their images (or to others’ images if they have been given permission to do so), or they may use an alternative spelling to the one you’re using.

Building names, place names or people’s names are likely to be spelled in different ways by different users, so it’s worth carrying out a few searches using alternative spellings. Remember that Flickr is used globally and many images will be tagged in the user’s native language. Bear in mind also the use of US alternatives, e.g. gas for petrol.

Photo by J.Salmoral on Flickr - used under a Creative Commons licence

Users add tags by entering space-separated words for each tag, e.g. museum london england. They can add a phrase of two or more words by using double quotes, e.g. “national portrait gallery”. Users may not always do this so their image will have three separate tags: national, portrait and gallery - if this is the case the image will not be returned in a phrase search for “national portrait gallery”.

Some users will allow you and others to add tags to their images - this can be useful if they haven’t used a term you would use to describe the image, especially if you need to search for it again or have added it as a favourite and want to search through your favourites (see Favourites - returning to images you’ve saved below). However, don’t rely on a tag you have added to someone else’s photo remaining there forever, as users can delete tags (as well as comments and notes) made by others if they want to.

In addition to any tags a user has added to the image, you’ll see any sets they’ve placed the image in. Users create their own sets to organise their images, and you may find it useful to browse sets for other similar images. The image may also belong to pools (see Group pools below) and if it does these will be listed beneath the sets and above the tags.

Sorting your search results

If you are new to Flickr you may find the sheer number of images off-putting. It’s sometimes difficult to know where to look as you start wading through the thousands (or millions) of results returned, so it’s worth pointing out that there are three ways of sorting the images:

Most relevant is the default and will sort images by those that most closely match your search criteria (i.e. the term will appear in the title, description, tags, comments or notes)
Most recent sorts the images by those most recently uploaded. Note that they are sorted by the ‘Uploaded on’ date rather than the ‘Taken on’ date (see also Date searching below)
Sorting images by most interesting is often a good place to start if you have a large number to look through. Flickr uses a complex algorithm to give each image an ‘interestingness’ score - the higher the score, the higher up it appears in search results

A photo becomes more ‘interesting’ according to various factors such as how many times it has been viewed, how many people count it as a favourite, how many people have commented on it, how many pools it belongs to, and other assorted characteristics.

Photo by MorBCN on Flickr - used under a Creative Commons licence

It’s not just ‘how many’ but ‘by who’ and when - i.e. if a user with a high interestingness ‘score’ comments on a photo, that comment will count more towards the photo’s interestingness than a comment from a new user. If x number of people mark it as a favourite within the space of a few hours, its score will be higher than if the same number do so over a longer period of time.

Flickr uses the 500 most ‘interesting’ photos uploaded each day to populate its Explore pages, giving you the option to browse through ‘interesting’ photos using a calendar.

A useful account of what ‘Interestingness’ is is available as is a full description of the ‘Interestingness’ algorithm in the patent application.

So, sorting by most interesting will not necessarily show photos that you consider to be the most interesting, but it will show those that other users have clicked and commented on more than others.

At the time of writing (July 2009), Flickr is beginning to roll out a new layout for search results. It’s being beta tested by a small number of searchers initially (ourselves included), and includes a few useful new features - so depending on when you read this you may find you are able to:

Exclude photos by a particular user from your search results - this is useful if you are sorting by most recent as you will often find one user who has uploaded an entire holiday’s worth of pictures using the same description or tags for every photo regardless of actual content
View related ‘things’ in a side panel - e.g. group pools or photographers who have content that relates to your search; narrow your search to a particular location. Be aware that if your current search is for Creative Commons licensed material only (see above), and you click one of these related links it will no longer be limited to Creative Commons material
Choose the new ‘Medium’ view - in addition to the existing Small (was called Thumbnail) and Detail views, the new Medium view is useful for scrolling through larger previews without accompanying text
View more images per page - 28 as Small (was 24), or 60 as Medium or Detail (was 24)
Read more information about each image when not in Detail view - in Small and Medium view you can now click the new (i) information button to display the same info you get in Detail view without leaving the page

Group pools

Another way of searching Flickr is via groups. Any signed-in user can set up a group to pool photos from other users. There are thousands of public groups covering a broad range of subjects, for example:

Photo by Mark Strozier on Flickr - used under a Creative Commons licence

If you want to find out whether there is a group that covers your area of interest, you can use the group search page.

Most groups encourage users to add their images to the pool: consequently, some groups are huge with thousands of members and an even greater number of photos.

The more specialist groups can be very small, and some are set to private where only invited users or contacts of the group administrator (the person who created the group) can view and/or submit photos.

Anyone can search photos by group. Some groups have fairly strict criteria for photo submissions (e.g. users must be invited or nominated), so can be useful filters for ‘good quality’ photos of certain subjects. Other groups allow anyone to post any images regardless of quality.

You can switch from a thumbnail view of group photos to the world map to see all that group’s ‘geotagged’ photos (see Finding images using maps below).

Once registered as a Flickr user, you can join existing groups or create new ones. Being a member of a group allows you to filter your searches to that group only. Before creating a new group, it’s worth looking to see if one covering similar material already exists.

The Commons: images with no known copyright restrictions

As mentioned earlier, The Commons is the place to look for images with no known copyright restrictions.

The Commons is Flickr’s partnership with nearly 30 publicly-held photography collections from around the world. The participating organisations have selected thousands of historic ‘copyright-free’ images from their collections and made them available via Flickr.

Among the collections taking part are:

The Library of Congress (US)
George Eastman House (US)
Smithsonian Institution (US)
Brooklyn Museum (US)
Bibliothèque de Toulouse (France)
Nationaal Archief (Netherlands)
Biblioteca de Arte da Fundação Calouste Gulbenkian (Portugal)
Powerhouse Museum (Australia)
Australian War Memorial
National Library of New Zealand
Swedish National Heritage Board

...and from the UK:

Photo from The National Library of Wales on Flickr: The Commons - No known copyright restrictions

There are two main aims of the Commons project. Firstly, to increase awareness of and access to the photographs, and secondly to encourage people to share their knowledge by contributing their own information about the photos (via comments, notes and tags), thus enriching the collections’ own catalogues.

The additional benefit is as a source of images that can be used free-of-charge and straight away... Well, almost straight away: you are advised to first read the The Commons Rights Statement in full. Note that each institution has a link to its own rights statement from this page and also from the ‘No known copyright restrictions’ link under each image.

You can either search the Commons for images from all contributing organisations, or browse each collection’s contribution by clicking their icon on the main Commons page. Note that while some of the organisations use Flickr for their Commons images only, some use Flickr to share other images which are not part of the project - these images will have different licences, so keep an eye on the rights statement associated with each individual image.

Date searching

With the Advanced Search, you can search for images taken between specific dates.

If you’re not looking for anything specific but just want to see any images taken between two dates, you can enter the dates and leave the other fields blank.

You don’t have to enter dates in both the ‘after’ and ‘before’ fields - leaving the ‘after’ field blank will search for any images taken before a particular date, and vice versa.

As well being able to search by the Taken on date, it’s also possible to search by the Uploaded on/Posted date. This can be useful if you are regularly searching on a particular tag and want to quickly see what’s been posted over a certain time period.

Photo by Alan K. Weeks, Dorothy Peyton Gray Transportation Library and Archive at the Los Angeles County Metropolitan Transportation Authority on Flickr - used under a Creative Commons licence

With any date search, be aware that the dates being searched on (those displayed next to each image) are not necessarily accurate and you should not rely on either as being factually correct:

The ‘Taken on’ date is provided by a digital camera’s EXIF data if available. If no EXIF data is available, the date will default to the date the file was last modified.
Although most digital cameras now record EXIF data, be aware that if a user has not correctly set the date/time on their camera the ‘Taken on’ date shown by Flickr may be incorrect.
If someone has scanned a print or a negative, there will not be any EXIF data and Flickr will use the date the file was last modified.
If the original photo does have EXIF data but the photo is then edited in image editing software and resaved, the EXIF data may disappear - again the ‘Taken on’ date displayed by Flickr in these cases will revert to the date the file was last modified.

Also note that users can edit all date information after they have uploaded photos to Flickr. So, for example a photo that was taken on 24 March 1974, scanned on 30 June 2004, cropped and resaved on 18 December 2006, before finally being uploaded to Flickr on 17 May 2007 will have the following default information: Taken on: 18 December 2006, Uploaded on: 17 May 2007. Users can easily change this to reflect the real or approximate (or completely made-up!) date the photo was taken.

It is worth bearing in mind, especially when sorting search results by Most recent, that users are also allowed to amend the Uploaded on date (they might want to do this to change the order in which their images are displayed - by default they are shown in reverse date uploaded order). However, the Uploaded on date can only go back as far as the date the user signed up to Flickr.

Finding images using maps

As you browse through images, you will see that many display location details - you will find this information below any tags and above the camera and date information, e.g. Taken in Clifton Village, Bristol (map)

Photo by Joe Dunckley on Flickr - used under a Creative Commons licence

This information only appears if a user has ‘geotagged’ the image, which they can do by dragging it to a specific point on a map. In February 2009, Flickr reported over 100 million geotagged photos.

If you click on the map link next to the location information, a pop-up window appears showing a thumbnail of the image pinpointed on a map of the local area. You can then zoom further into (or out of) the small map, or click to See nearby photos and videos which brings up a full screen map showing all the images other users have added to that area.

You can also search by location - either by typing a location into the search box, or by exploring the world map. This can be useful if you are researching a particular area, or want to see what a place ‘really’ looks like: i.e. from the public’s point of view as an alternative to promotional photographs of an area or building.

A location search for ‘london’, or viewing the map zoomed out to encompass all of London, will return over 2 million images. As you zoom in the number of images decreases until you are at the highest zoom level. Points on the map will indicate the number of images in each location.

Be aware that some users may add/drag their images onto the zoomed out map without being specific about the exact location - so at street level on the map, you may find images of the London Eye in the middle of Brixton.

Location searches can be filtered by date, by group (if you are a member of any groups), or by person (if you have any contacts - see Making contacts below).

Another way to explore locations is by using the search box in the Places section. This will show your chosen location’s poular tags, featured photographers and related groups.

Finding photos taken by specific camera models

If you’re interested in seeing the sort of pictures a certain camera model can produce, you may find it useful to view some of the photos taken by ‘real’ users as an alternative to the camera manufacturer’s promotional shots.

Flickr lets you browse a list of camera brands and see all the models used by Flickr users. Clicking a model will bring up 18 ‘interesting’ (see Sorting your search results above) photos taken using that particular model. You can then view 18 portrait, macro, night, landscape, action or recent shots.

You can’t browse through more than 18, but on the same page you will see a search box which lets you ‘Find photos taken with the…’ same model.

Photo by fro_Ost on Flickr - used under a Creative Commons licence

Note that the Advanced Search page does not allow you to search by camera name/model, nor by any other EXIF data fields. However, many users add camera makes and models as tags to their images, or set up group pools specifically for photos taken with certain models, e.g. Nikon D300 Users or Canon EOS 5D Series.

If you are interested in the camera settings (or EXIF data) used for a particular photo, click the More properties link which appears beneath the camera model name (below tags and above the date). This will show you details such as exposure, aperture, focal length and ISO speed. Note that this information only appears for photos which have kept the camera’s original EXIF data: if a user has edited and resaved an image, sometimes this data is removed.

Favourites - returning to images you’ve saved

Any images you come across that you would like quick access to in the future, can be marked as favourites (Flickr uses the US spelling ‘Favorites’). This is especially useful if you are researching images for a particular project over a period of time.

You can search within your favourites, and because Flickr is browser-based, you can easily access your account and your favourites from anywhere with an Internet connection.

Marking images as favourites is also useful if you are working collaboratively - if you and others are sharing one account you can all add/remove favourites, or if you and others are all Flickr members, you can visit each other’s pages to view their favourites.

Photo by i_gallagher on Flickr - used under a Creative Commons licence

Note that this method of storing other people’s photos is not as sophisticated as some lightbox functionality you may have come across on other image sites, and it’s worth noting the limitations:

You cannot create more than one set of favourites or organise them by folders
Once you have added images as favourites, you cannot alter the sort order - they appear in reverse order from the first added. If you really need to, you can remove an image from your favourites, then re-add it to make it appear as the last added
If a user removes one of their images from Flickr, it will disappear from your favourites without warning or notification.

Making contacts

It’s also possible to look at other users’ favourites - this can be a useful way of discovering images you wouldn’t necessarily come across through searching. Once you discover other users who seem to be interested in similar photos to you, you may find it useful to look at their own photos, or you can add them as ‘contacts’, or look through their existing contacts to discover new photographers.

Once you add someone as a contact, you’ll be able to see their new photos as soon as they are uploaded - they will appear on the Your Contacts page. Your contacts, your contacts’ favourites and your contacts’ contacts will soon grow and can become a good way of filtering out photos you’re not interested in.

Sharing non-public images

Friends, colleagues and other contacts you make may give you access to images that are not available publicly. These will be images they have set as ‘private’ which means they can be shared only with specified contacts, friends and family. It’s a useful way for people to share images that they do not necessarily want others to see.

Groups can be made private too, so only those invited to do so can add and view images in a private pool. This can be a handy way of sharing photos from a conference or other group event, where multiple attendees have taken photos.

Comments, notes and discussions

You don’t need to spend long on Flickr to notice the comments beneath many of the photos. Many of these will be of the ‘Nice photo’, ‘Great composition!’ variety, others will be invitations to post the photo to a certain group pool. Some comments will be personal remarks from friends of the photographer, while others will offer constructive (or not so constructive) criticism and, perhaps of most use when looking for images, may point you to similar photos taken by other users.

Users can also add notes to their images - these appear as rectangular text boxes directly over the photo as you move your mouse across it, and can be used to describe or comment on a particular area in the photo. If a user specifically allows it, other users can also add notes - like comments, these can have their uses, e.g. if they (correctly!) name a particular building or person, or point you to related images.

Photo by topherous on Flickr - used under a Creative Commons licence

Flickr’s public forum and the discussions specific to group pools can also be useful places to discover images. The forum is intended for users to post questions and ask for help, while pool discussions can generate interesting debate on more specific topics. Depending on the group, pool discussions can be used to seek feedback from others on a piece of work, provide critiques, answer technical questions, or point out interesting images by other users.

Subscribing to photo feeds

If you are familiar with RSS (Really Simple Syndication), you can subscribe to a number of photo feeds: e.g. specific users’ photostreams, particular tags, or photos in your choice of group pools.

If you are not familiar with RSS, the BBC provides a useful summary. There are plenty of free RSS readers available and subscribing to photo feeds is a very easy way of keeping up to date with newly published images, without having to visit a particular user’s photostream every few days, or repeat the same search over and over.

Other ways of finding Flickr images

There are a number of third party services that let you search Flickr in some interesting ways. Using Flickr’s open API (Application Programming Interface), anyone with the technical know-how can write programs to “present public Flickr data (like photos, video, tags, profiles or groups) in new and different ways”. Here are a couple of examples:

retrievr A type of CBIR (Content Based Image Retrieval) - lets you draw a rough sketch with your mouse using different colours and brush sizes and returns images based on your sketch. The results are mixed, but it works better with large swathes of colour or basic shapes. You can also upload an image or enter its URL to search for ‘similar’ images.
Colr Pickr Select a colour from the wheel, use the slider to increase or decrease the brightness, and images matching those colours are returned. The default set of images come from Flickr’s Color Fields group pool, but it’s possible to search other pools, such as Flowers, Graffiti, Doors and Windows, Macro, and Urban Decay.
A further selection of third party Flickr services and applications are listed

It is also possible to find Flickr images through image search engines, but the results will inevitably not be as accurate or up to date as when searching Flickr directly.

If you are looking for Creative Commons-licensed images, you can also use the Creative Commons search site but note that the search results are exactly as they would be if you were searching Flickr directly (see Using images you find on Flickr above).

It’s also possible to search for Creative Commons-licensed images via Everystockphoto. This site indexes images from Flickr as well as a few other ‘free’ image sites and lets you filter results by licence type. It also offers a couple of extra features that Flickr’s advanced search does not have, such as filter by shape (portrait, landscape or square) or by minimum width/height.