Pixels required for a large print

[wavman79]

hi,

If I wanted to have a digital photos put onto a large box canvas. Say maybe about 23" across. What sort of megapixel camera would be best? Or is it just a case of the most I can afford? Or are there other contributing factors I should take into consideration?

Cheers,

Dan:roll:

[tmoreau]

There is almost no limit to the number of contributing factors, but some 'general guidelines' can be discussed as a starting point.

(I will assume in the following text that pictures are taken with high quality equipment by a skilled photographer)

300 pixels per inch is a VERY high quality print, the kind you can put right up to your eye and study minute details, perhaps with a magnifying glass.

150 pixels per inch is still a reasonably detailed print, if handled carefully can look drop-dead gorgeous.

You could reasonable expect to be within this range with your native image to get the absolute best results. Subject will have an enourmous effect on resolution requirements, as does printing method, viewing distance, and so on. Some subjects need more resolution to 'look right', some can get away with much less. If viewing the print from 20 feet away, you can get away with much less resolution. Lots of factors.

Hm, 23"x15" (about A2) at 150ppi would be 3450x2250 (7.7mp). In theory at least, something like the Canon 30D could be 'adequate'. If you wanted absolutely perfect fine-art prints of that size at 300ppi, that would be 6900x4500 (31mp). That would require medium format, a $20-50k digital adventure.



Have you ever printed anything like this before, or just deaming?

[MrPogo]

The most you can afford in some respects: You'd probably need a 10MP camera to get a printed resolution of about 150dpi at that size, which you wouldn't really want to drop below (I'm just guessing at the height of the image compared to the 23" width).
On the other hand however, and image that size would mainly be viewed from a distance rather than close up, in which case the results from a camera with fewer megapixels would probably look just as good from several feet away.

[wavman79]

Thanks guys, what I'm actually aiming for is to get a camera to take on holiday with me to NZ with the hope of catching some amazing scenery and that one of my photos will look suitable for a picture on the wall.

I currently only have a 3mp camera, although my girlfriends is 5mp I think...but have had the use of a Nikon D70 through work so have got the taste for nicer pics! Think I want to stay down the digital compact route rather than an slr just for ease of carrying around.

So if I got something in the 7-10mp range I should be ok? The 30D? Is that an SLR?

[MrPogo]

The D30 is an SLR (and quite a pricey one at that ). You should be fine with that sort of megapixel range (your girlfriend's 5mp should just about manage it), indeed the other capabilities of the camera should make your final decision rather than just the megapixel rating (there's no point being able to get a slightly nicer print from a camera that can't capture the image as nicely in the first place!).
The best thing to do is decide on a budget and look through a lot of reviews

[wavman79]

thanks MrPogo....review digging commences...and if I can't make a decision / carry on at my current rate of spending for this trip then I may just take the gamble on the 5mp camera producing the goods!

Guess it might depend on what deals come to the surface during the run-up to christmas!

Thanks again for your help...must stop thinking about cameras and do some work now :?

[Tostada]

Are you guys sure about this 150+ DPI thing? That's the kind of resolution you need for good prints on photo paper. When I think "box canvas," I think of a textured wall print that really isn't going to make any difference at all when you go past 72 DPI. Not because you won't be standing close enough, but simply because the material won't resolve that kind of detail any more than if you were trying to put heavy construction paper in an inkjet printer.

6.0 MP is going to give you 104 DPI on a 27" wide print, and I can't imagine the need for more than that.

I've printed many 13x19" prints using 300ppi & my 6MP Konica Minolta 7D. It's just a matter of knowing how to best upsample an image to get the best results. Try doing a search in the forums for "upsample".

[JimC]

Subject type plays a role, too.

For example, Portraits tend to be better candidates for very large prints viewed at closer distances, since you have a large number of pixels representing your subject (versus something like a landscape taken with a wider lens, with a small number of pixels representing distant foilage).

Lin Evans has an excellent forum post on this topic here (see the 2:18PM post from October 13, 2004):

http://www.stevesforums.com/forums/view_topic.php?id=19609&forum_id=79&jump_t o=166037#p166037

[wavman79]

Thanks guys, have read through all that stuff in the other post and kind of makes sense to me!

I think I would probably be ok with a 5mp camera for a portrait type picture, but as I want to take scenery type shots then maybe I should go for a little more! Don't need it till end of December and we usually get to spend our work christmas bonus in time to get our stuff before crimbo...so maybe that's what this years bonus will go on

Anyone know much about the casio elixim? Liking the large screen on those!