Photos of Israel...What size to enlarge to?

Hello everyone.

 

Thanks for reading my question.

 

I have taken a number of photos while on a trip to Israel last week using a Nikon d200. Photos were taken

at fine JPEGs.

 

Some photos are sharper than others but my question is how do you determine what is the largest size

you can enlarge a photo.

 

Not sure if I am wording this right. So using a D200, the file sizes of the photos are good enough to

produce a 16x20 poster. But the photo needs to have a certain amount of sharpness to be able to

produce a nice poster.

 

IS there anyway to get an idea if a photo will look good blown up without printing it first?

 

Also, I sometimes read member referring to 100% crop, 50% crop. What does that mean?

 

Thanks for your help.

 

Regards...Ashk

 

PS. I will be using outside printer like Ritz or Wolf to to the enlargement.

The imagesize of the D200 is roughly 3900x2600. As a rule of thumb ... if you want excellent print quality, you want 300 pixels per inch (of print). With that, a 3900x2600 will produce up to 13x9 (inches) (which is 33x23 cm). For an image quality which is still acceptable, you can go down to 100 pixels per inch. With that you image size will be up to 39x27 (inches) (about 100x70 cm).

 

If you want to check if your image is reasonable sharp at that size, you can print a small part of your image to a smaller (and cheaper) format. It's important, that you use the same number of pixels per printed inch as you would use for the big print.

 

For example, if you would like to print to be 60cm x 40cm and your testprint will be a 15cm x 10cm you only want 970 x 650 pixel for this testprint. (970/15 = 3900/60). When judging your testprint, dont forget that the final print will be whatched from a certain distance

(which is usually bigger that the distance you watch a small print from).

It's all about viewing distance. You can go to billboard size if you are viewing from the highway.

It is OK to resample an image so that larger prints can be made. The purpose of resampling is to keep individual pixels from being visible at close examination. With resampling, a D200 can produce excellent 11x14 inch prints and acceptible 16x24 inch prints.

 

There are two ways (besides experience) to see if the enlargement will work. The best way is to resize and resample the work then crop an 8x10 out of an interesting part and print it at that size on your home printer. Another way is to view the image (after resizing and resampling) at the pixel level. This is an option in Photoshop, and means that each pixel in the image is mapped to a pixel on your screen (e.g., 1024x1280).

The final resolution should be 300 ppi, to effectively hide the pixels. This is true for any print people might hold or step up to hanging on the wall (but not billboards, where pixels might be 3 or 4 per inch). You begin to see granularity in fine detail, especially highlights, at 200 ppi or less.

Oops! You were shooting in JPEG mode. JPEG mode leaves artifacts, like confusion in repetetive patterns (cloth, bricks, etc) and in-camera sharpening leaves halos around edges. These artifacts will be faithfully enlarged along with the desired details.

 

Next time, shoot in RAW mode. If you see the other person who still uses JPEG, tell him/her too ;-)

Ashk, I think your answer depends on a few things. One of them is the type of file you're using (and you told us you're using JPEG fine). Another thing depends on what type of lens you're using. Of course, the better quality lens you have, the better result.

 

My guess is you can probably print to 13 X 19, no problem, as long as the original file is in focus. I can't speak for larger than that, I just know that I get good quality at that size using a D80 (10 megapixels, like the D200).

 

We all learn as we go along. From what the others have said above, maybe you'd want to shoot in RAW format the next time. I know I learned the hard way. I only shoot RAW now.