Rotating JPGs

itm2

I'm thinking of using Irfanview to rotate my photos 90 degrees where they have been shot in portrait mode. I believe that Irfanview does this without any loss of picture quality, but my question is: if I send rotated JPGs to a photo printing service will they print them correctly? (i.e. will the fact that they've been rotated "confuse" the printing service, and result in the picture being printed sideways on the paper, with black lines on each side?

I'd be keen to get feedback from anyone who has done this.

TIA
Ian

Omertron

There should be no difference between a rotated picture printed or one in either landscape or portrait mode. I've not had any problems with printing either rotated pictures or normal portrait/landscape ones.

b33r

Nope you only lose quality if the angle you change the photo too is between 0-90. There is no quality loss on 90, 180 and 270 degrees.

Also, why do you need to use infanview to rotate them, windows picture viewer built into windows (assuming you are on windows) is perfectly capable of doing a simple rotate.

Screeny:

itm2

I'm not sure if the Windows picture viewer will do the rotation without loss of quality. I checked JPEGclub.org and it's not on the list of applications which does:

http://graphicssoft.about.com/cs/digitalimaging/f/rotatequality.htm

b33r

Ah true yeh, i just tried it on a bunch of images, some just do it but some warn you there may be a loss of quality, isn't something I've done often enough to notice.

It might be better to backup the ones you intend to rotate for use in printing then just rotate them for the sake of viewing on screen, slide shows etc. as i imagine the loss of quality is minimal.

GoofyGAT

As Omertron suggests, you don't need to rotate them at all when sent for printing.

But if the pics aren't in the same format as you're going to be printing them in*, & if using an online printing service, you'll want to make sure the pic fits in the print preview window without getting cropped in undesireable places.

*E.g. They could originally be in 1600x1200 format (more suitable for 8x6"), when you actually want to print them in 6x4" - in this case, the pics get cropped by default. Hence you may want to ensure they're cropped according to your needs, & not the default that's offered. G