Large Prints and Mega Pixels

[paulina]

Hi there,

I am about to start a series of landscape photos that I want
to get printed a bit large, at least 20x24 inches. My question is:
how many mega pixels my digital camera should have to be able
to get the shots printed with a good quality at a proffesional lab?

I am buying a new SLR camera and I am wondering how many mega
pixels are need it to accomplish a good quality when enlarging. The ideal
for me will be not to spend a lot of money and buy an SLR 8 mega pixels
camera, but I don't know if that will get the job done. I need some
experts to advise me.

I have done some research around, and found out that there is
some software that increases the size of the images so you can make
bigger prints, from your digital ( http://www.benvista.com/main/content/content.php )
camera shots. Also, I found some labs (surfing the net) that claim that
they can print really large images (with no quality loss) made
with 5 mega pixels cameras.

I found the info about all this a little confusing and need some
guidance. Any answers and feedback will be greatly appreciated.

Paulina Hall

[stupot]

welcome to the forum. im sure 8 mp will be fine - canon 350d. i dont know much about upsizing images but from whats been said on these forums i dont think you'll have any problems.

[Longwatcher]

for a 20x24inch prints you should be able to get away with a good 8MP camera.
The catches are it depends on content of the specific photos. most will probably handle the upsizing with little trouble, but you may find some images do not resize well.
Generally all images will handle a doubling of the pixels with little to no "noticeable" effect. more then that depends on the complexity and content of the scene.

You want at least 240 pixels per inch at time of printing and more (up to about 360PPI) tends to be better (240, 300, and 360 PPI or DPI are common settings). So divide the number of pixels your camera has by say 240 to determine what the native size of a print would be. You can basically double that and still gaurantee full quality. More then double and you may have issues occasionally.

Also take into account any cropping you may need to do or desire. If you never crop then you can stick with the native values, but if you crop then you need more pixels to accomodate that factor.

So short form,
you can do it with 8MP (or even 6 although that is pressing it), but more is better. The 30D is 3504 by 2336 pixels so at 240DPI this means 14.6"x9.73" native, doubled is 29.2 x 19.46" or just shy of the 20" you need, close enough you should be able to get away with it as long as you don't need to crop a lot off the short side. at 300 or 360DPI if that is what you decide you need for that little bit extra quality then 8MP may not be enough. 240 is better then all but someone with a loupe is likely to notice though.

Hope that helps,

[Photodawg1]

I have 20D and just sold two 30" x 45" prints.

[md_129]

You should be okay with the rebel, here is a brief article about interpolation http://www.outbackphoto.com/workflow/wf_60/essay.html

I would suggest letting the print company upsize your photos for you or have them suggest the apporiate way to do it. You will find that every printing place has their own way of doing things specific to their equipment.

[SWPhotoImaging]

If you make sure to get the exposures right, and the focus accurate, a 6MP will do it. I have produced quite a few 20x30 prints from my trusty 10D. The better the original shot is, the better it wil enlarge. The current crop of 8MP cameras will do it very well.

[paulina]

Thank you very much,

very helpful answers and recommendations. I really appreciate them.
Now I feel confident I will be able to accomplish those 20x24 inches
prints.

I will buy the Rebel.

I was thinking, that maybe in a few years, printers/labs will be very
advanced and mega pixels on your camera will not matter that much as long
as you have a well taken shot. At some point I assume, printers will
be able to produce very large prints (60x70 inches or more) at really
high quality, with pictures taken with 8 mega pixels cameras.. I have sometime
to get good at photography before this happens so, that is good;-) Maybe then,
in a few years, I will be able print my 8mp pics at 60x70 inches or more, with
not quality loss.

:-)

[ghosh]

Hello paulina
Some times back even I had a similar thought ...
check this link http://photography-on-the.net/forum/showthread.php?t=159915&highlight=ghosh

[StealthLude]

more MP the better, but im sure you can get away with 8MP

Id love to get my hands on a 5D or a 1Ds for large prints tho.

[gmen]

Some useful links, articles and information here:

http://www.interpolatethis.com/

---- Gavin

[SonyaL]

I just read that article great information on there who would have thought a 6MP pic would have been able to be on the complete side of a semi truck trailer thats amazing.


Sonya

[PhotosGuy]

Remember, a 3 pic pano would about double your available MP.

[Mike Panic]

it is not the megapixels, it is the quality of the sensor, the glass used and the exposure.

i recently had a fine art print made 22.5x30 from a 4mp camera... yes 4mp! it was a canon 1d w/ an 85 f/1.2 lens on it, it looks sharp as a tack and flawless.

a 4mp p&s would not yield such a result

an 8mp p&s more then likely would not yield the same result

since the sensor in the rebel xt, 20d and 30d are the same, your more then fine. If you plan on doing any cropping or making prints larger then that, look at something like the 5d or a used 1ds (mark 1)

[Wilt]

One factor mentioned by no one is the VIEWING DISTANCE expected. While 'normal viewing distance' is often described as 1.5x the diagonal distance of the print, often viewers look from too close a distance simply because the print may be on an easel near their face rather than on the wall5' away, for example. So quality of the image ends up with far more scrutiny on the easel or table than on the wall. A low res picture can look surprising good from farther away!

[reewik]

I also shoot with the 4mp 1D and have a really nice 24x36 poster at home on the wall that looks fantastic. It was even a crop... I agree it is the sensor size not the MP.

[ecalpemos]

depends on so many factors, sensor size, engine, lens, mp, what type of pic it is. I have prints up to 1m by 70 cm on my studio wall, they are from both 8 mp cameras and scanned hasselblad but the interesting thing is some are also from a five mp camera, with a leica lens sure but still 5 mp.*digilux 2

[song4themoon]

I shoot with the 20D (8 Megapixel) and 20x24 is fine for printing pics taken with that camera