How large can I enlarge my photo?

Philby

I've got a picture that I'd like to get enlarged for a friend's birthday.

It was taken with a Kodak dx6490 (4 Mega-pixel) & zoom was not used.

Does anyone know what size this picture can be enlarged to (without a noticeable deterioration in quality)?

Cheers.

dbnavan

Philby wrote:

I've got a picture that I'd like to get enlarged for a friend's birthday.

It was taken with a Kodak dx6490 (4 Mega-pixel) & zoom was not used.

Does anyone know what size this picture can be enlarged to (without a noticeable deterioration in quality)?

Cheers.

The more u enlarge the more noticeable the deterioration, bring it to a Kodak Centre they will advise best, most photo shops now do digital prints

Thirdfox

A bit off topic but I just found this thread name hilarious (from my CP)



Back on point I find that my Konica Minolta (5MP) can print A4 pictures which are good enough to frame.

Oriel

You're probably looking 8"x11".

andy1249

OK , heres how it works , the 4 megapixel range of the camera will have a figure associated with it , something like 2304 x 1728 , this is the actual amount of pixels in the image ,

now picture quality is measured ( or can be measured ) in DPI which is dots per inch.

If you call each pixel a dot , then that gives you a good guide as to how big you can print , 300 DPI is generally considered very good print quality , so divide the numbers ( 2304/300 , 1728/300 ) and that should give you a size.
In this case its , 7.5 x 5.7 or 8 x 6 inchs approx.

Sometimes , especially if your camera has a raw (tiff , CS2 etc. ) mode , you can drop the DPI and still get very good quality , say to 250 DPI or even 200 DPI. but this will largely depend on your camera and how it stores images.

Note that compression ratio in the camera has a lot to do with the above , a high compression ration means you cannot enlarge as much. But you can take the above as a good rule of thumb.

By the way , 2304 x 1728 is a 4.1 megapixel image.

Gordon

I work in an image distribution/licensing agency for print publications. We use a piece of software called "Genuine fractals Printpro" by lizardtech software to pump up images. With this we do a maximum of 50% increase in size, depending on original quality you can pump it up more though but it may look a bit funny. That may be something to look into though.

Thirdfox

But does that mean my 5 megapixel camera (2592 x 1944) can only print high quality 8 x 6 pictures too? And you'd need an 8 megapixel camera to get 11 x 8 prints?

dalk

I've printed 2 megapixel shots up to A4. They look fine viewed from a few feet away... Close up and you can see some pixelation.

So you should get good results. (unless you like viewing pics held straight in front of your eyes. )

andy1249

Remember 300 DPI is considered very good image quality, considered a rival to film at this level of detail , and yes it is approx one dot per megapixel so even a Canon D20 ( 8 MP ) produces only 10 " by 8 " at this level ,

most 3 - 4 megapixel cameras can print up to A4 at reasonable quality but you will see some digital artifacts , at 6 x 4 , ie normal print size , you get great photos , which is what these cameras are designed to do ,

A lot of compacts compress by about 2 to 1 at fine quality jpeg ( note jpegs are always compressed to some extent ), raw is usually uncompressed , and these give you dot per pixel image sizes , depending on the compression and on the subject of the photo , 200 dpi may well be good enough , even 150 DPI is good enough for some pictures , but for sharp clear images with no evidence of digitising , 300 DPI is considered the standard.

Thirdfox

So what cameras do they use to print off those magazine pictures e.g. A4 great detail photos?

And does that mean any film camera can be magnified to poster size (or does that then depend on the film used?)

andy1249

This is and excellent little reference with a table included ,

http://www.worldstart.com/tips/tips.php/1332

for 300 dpi print quality at A4 you would be looking at 5 megapixel and up ,

however as the link will tell you , sometimes 200 dpi looks just as good , this being the case , then that increases your size by a third , 150 dpi doubles the output size. Its a question of suck it and see !!

Poster size prints are usually done on some kind of medium format film camera ( 4 x 5 negatives ) or the likes of a 1ds mark II , ( 17 megapixel , and also about €8000 ) way beyond most of us at the moment.

Philby

Thirdfox - ha ha, quality.

Mine is 230 dpi and 2304 x 1728 pixels so if I apply that equation that gives me 10 x 7.5 - would I probably get away with 10 x 8?

Philby

I got it printed 8 x 10 in Jessops (matt finish). Turned out very nicely, could've gone up another size fairly comfortably I think based on the results at 8 x 10. Cheers for the advice

Shrimp

3 megapixels = 4x6
4 megapixels = 8x10
5 megapixels = 11x14
7.1 megapixels = A3 print

Remember it also depends on your DPI, and RES saved at..

The above would all be very high quality prints.