quick printing question

I had a customer order a 24x20 print of a photo but my dumb a$$ deleted the original photo all I have a copy of this photo is a 1800px x 1200px @300dpi copy. My question is will this be okay to enlarge to the 24x20 print, I tried to download perfect resize but I didn't like the result in photoshop.

thanks any help would be great.

Pixel density affects both subject detail and also the aliasing ('stair stepping') of edges which are not perfectly aligned with the rows and columns of pixels.

With a lower res source image, you will have less ability to stand close to the print (which is what folks typically do, though not necessarily proper procedure) and peep for density of subject detail, and also you will detect the aliasing more easily. Additionally, detail density also accounts for what the brain perceives as 'sharp'.

Your 1200pixel high source image on a 20" tall print results in only 60 pixels per inch on the print...and that is universally thought to be poor density, resulting in the brain perceiving 'not sharp'

Your image would make a "reasonably good" 8x12 print (150 ppi) -- not great but for most purposes decent. Beyond that, as Wilt says, fine detail will start to break down in one way or another.

That being said, your client may not be picky, or the pic may be viewed at a distance, in which case a larger print could be OK. Just bear in mind that it won't be "gallery quality"!

Consider that viewing distance is a very important consideration. That 24x20 print viewed at 24" may well be considered to be 'poor', but if viewed at 48" away routinely it becomes acceptable in quality.

I printed off a test copy of that size and its not bad, could be a lot better but viewing from a distance you can't really tell.