Geograph - photograph every grid square

All submitted images have a unique identity number. It forms the last part of the URL (web address) of the main photo page.
example: http://www.geograph.org.uk/photo/4 is the first 'live' image on the site and has the ID number 4 (we don't use leading zeroes) while http://www.geograph.org.uk/photo/4018397 was the four millionth to go 'live' on the site (we do get a few rejects or failures) and has the ID number 4018397.

If the image has not yet been moderated go to the 'Change image details' page and click the [request rejection of this image] button, explaining it is the wrong image.
On a moderated image, open the 'Change image details' form and, in the box near the bottom of the page labelled [Please describe what's wrong or briefly why you have made the changes above...] ask for the photo to be rejected and give your reason. Don't forget to click the box marked 'Bring this issue to the attention of a moderator' before clicking [Submit changes].

Short answer - please don't!
Editing out what is there by stamping another part of the image over in order to produce a 'prettier' picture is not what Geograph is about. We aim to record what is there, not a prettified version of it.
If people happen to be in your photo and you think they may object to the image appearing on the internet, consider if you are prepared to deal with any objections they may raise. If not, best not to submit. That said, I can only recall 2-3 images being removed from view because of objections raised by people (known to the photographer) who appeared in them - in the 11 years since the site started.
Some submitters do blur out legible vehicle registration plates. Opinions vary as to whether this is necessary or desirable but it is not a reason for rejection if subtly done.

Once you have pressed the "I agree" button your picture is in the system and subject to the Creative Commons Licence.

If the picture has not yet been moderated, you can requested for the image to be rejected, and you will be asked to give a reason. To "self moderate" in this way you click on the "Change Image Details" link under the picture: you should see an icon for "reject".

Once the picture has been moderated and accepted you will probably need to give a very good reason for the image to be removed from display. Images may be removed from display if they were taken illegally, or, for example if a landowner objects to a picture taken from a place without public access. This process of removing from display is sometimes referred to as "vaulting" as a copy of the picture remains in the "vault": a file storage area.

See also "I have licensed an image larger than I intended, can I remove it?" http://www.geograph.org.uk/faq3.php#93