Photo rendering with jagged edges

[sananda]

hi

i have a question about photo rendering.

if you look around the edges of the temple in this photo you will see that they are not smooth: http://farm4.static.flickr.com/3154/2609638543_2a6a7588c9_b.jpg


but after i zoomed in very slightly the edges rendered smoothly as anticipated: http://farm4.static.flickr.com/3026/2610472246_bc737084c3_b.jpg


i don't think it's a photoshop issue as it renders with the jagges edges in preview. i'm using a 17" inch imac (tn panel).

does anyone have any idea why this might be?

thanks.

[likeavaliant]

thats to be expected with the amount of zoom you are using.
19.5% of the photo will not render properly, where 25% will.

[ChrisA]

Photoshop does best if the zoom level is 1/n where n is some even power of 2. So that means for critical viewing use 1/1, 1/2, 1/4 or 1/8. In percent this works out to 100%, 50% 25 or 12.5% In these cases Photoshop cansimply show you every n'th pixel in all other cases it must interpolate. Interpolation always cause blur and or noise in the image.

And if you want to see what is really stored in the file the only way to know is to use 100%. That way a screen pixel equals a file pixel.

[taylorwilsdon]

Non-fractional (at the decimal level) zoom percentages will result in an accurate representation of the image.

You'll see the best quality at (I believe already stated but) 25%, 50%, 75% and 100%.

[sananda]

i see what you all mean. thanks everyone.