Sometimes i find good images online and I hope if I have it on my room wall, is it a good idea to print it and put on my wall? did you try this before? What's the most issues i should think about before doing that? are there any recommended steps i should follow? and what pros and cons.
Note: I will ask the Image owner before doing this and also will ask him to send me a higher quality one if needed. So I will never break Copyrights
There are technical issues, copyright issues, ethical issues and creative issues to consider.
Technical issues
1. The image will need to be scaled up in size. With the right software you can get good surprisingly good results. I printed a 1200 px wide image on A3 with more than acceptable results.
2. It is very dependent on the type of image. An image with many sharp edges and fine detail will not up-size well.
3. A canvas or semi-matt print surface is more tolerant than a fine glossy surface.
4. Placement has an influence since that will often control the viewing distance.
Copyright issues
As you noted, we should always respect copyright and ask for permission. One can make a strong argument that the greater good of society is best achieved by freely sharing creative work, which is after all what happened until 200 years ago. But the law, as it stands, does not support that position and becoming a scofflaw is not in the interests of society. I personally recommend that people publish their work under a Creative Commons licence unless photography is an important or main part of their income, in which case it is to be expected that they reserve all rights under copyright law.
Ethical issues
If you display work which is not your own you should always show the name of the author. If you don't there is an implication that it is your own work, which is decidedly not ethical. The author normally expects some kind of recognition which usually takes the form of attribution.
Creative issues
This comes down to asking the question, why are you, as a photographer, displaying someone else's work rather than creating and displaying your own work? There are good reasons for doing it. Other people's work can provide a powerful creative stimulus and source of ideas. All artists learn from their fellow artists work. We can use it as a reminder and an incentive to do better work. When we admire other peoples good work we enter a zone of openness and humility that allows the creative process to flower.
Copyright issues aside (I'm sure people more knowledgeable than myself will contribute on this), from a technical point of view it's possible, given the original is of sufficient resolution (image size). Minimum resolution figures are often quoted in the region of 200-350 ppi (pixels per inch) but it really depends on your viewing distance. If a small printed image looks sharp to you held at arms length in front of a wall, then the same image will look sharp when occupying the same amount of wall as outlined by the print. This gives you a means to make a small copy and determine whether it can be printed larger.
I will say this on the subject of copyright - it never hurts to approach the photographer and ask for permission, explaining that you appreciate the work and this is non-commercial usage. They may send you a high res version. Or not.
Speaking frankly to the copyright question, IMO it's perfectly ethical to take an image from the web and put it on the wall in your freaking private home, without asking permission.
Legality is a different question, of course.
I had a friend who asked my permission to do this with some images I posted and I directed him to larger versions for his prints. He initially asked me if I was selling them, but I told him to just download and print. It was actually quite flattering and the resulting treatment he did looked amazing, actually made me jealous of my own images!
Anyways, the moral of the story is that is doable and you can get great results. I think you'll find that some amateurs will be quite flattered by you asking. However, I'd caution that professionals will likely reject the request. I don't think you'd run into copyright issues if you ignored a "no" answer, since private use usually doesn't violate, but I think it would be a little questionable morally. In any case, there are billions of brilliant images online now, so you're bound to find plenty where the photographer will say it's okay.
Always ask the person who owns the image - I happily let people download some of mine to use at home. Like others have said it is always flattering. Quite often I will also make the higher res images available to them.
However - If I find that someone has used it without asking I do find it quite rude and will frequently ask if it is on a blog etc that it is removed.
