Question abt dpi & pixels

[mrdogbear]

Hi all,

I have a question abt the photo printing.

If I set my DC to take the photos at 1600 X 1200 resolution, how can I print those photos at 4R size?

Let me explain what I thought:

1. need to know the dpi of the printer, say 300dpi
2. so the max. pixels for this 4R(6x4) photos will be 1800 x 1200 pixels
3. it means the photos' quality will be affected as 300dpi printer will require 1800 x 1200 pixels

Conclusion:
If I need to print 4R photos at 300dpi, I need to set my DC to take photos at least 1800 x 1200 pixels. Am I right?

If the dpi of printer is higher, the photos requires higher resolutions.

 

[Snowcrash]

1600x1200 first need to crop to 3:2

then if you use the Length and width to (6x4 inch) resize in PS, the 72 dpi will change to 200++ dpi.

See printout whether acceptable or not.

As for sending to fotolab, I crop 3:2 (my photo is 1280x853), resize to 6x4inch in PS elements.

Choose cropped image and they will blow up to full 4R size.

Choose full fitted image and they will use 300dpi and cut away the borders for me (final size less than 4R)

Hope the above info helps.

 

[klsss]

ya i would need enlighten too , if i send a 4256x2848 to the lab to process to 4r photo , do i need to corp for them to print 4r size or they can print direct ?

 

[revenant]

Originally posted by klsss
ya i would need enlighten too , if i send a 4256x2848 to the lab to process to 4r photo , do i need to corp for them to print 4r size or they can print direct ?

If its not crop, they will crop for you but they might anyhow crop and may cut away some of the important parts that you want. So its best if you crop yourself before sending to them.

 

[Snowcrash]

Originally posted by klsss
ya i would need enlighten too , if i send a 4256x2848 to the lab to process to 4r photo , do i need to corp for them to print 4r size or they can print direct ?

Crop it in PS according to 3:2 to get full size 4R print.

If not use full image fit to get the whole photo in, but with borders (some lab might just cut off the borders for you, resulting in smaller than 4R size print)

 

[MatthewSCL]

You can request the shop to print with border, thus printing the ful frame onto the paper...but then you will have smaller images loh...since its not the full 4x6 you are printing for.

 

[Midnight]

Originally posted by mrdogbear
Conclusion:
If I need to print 4R photos at 300dpi, I need to set my DC to take photos at least 1800 x 1200 pixels. Am I right?
If the dpi of printer is higher, the photos requires higher resolutions.

You are absolutely correct to say that a 300ppi (pixel per inch) photo, strictly speaking, will require an image size of 1800x1200 pixels.

However, basically any image of the correct 3:2 aspect ratio will work as far as getting a successful printout is concerned. Although the physical dpi (dot per inch) of the printer will indeed vary, the printer software will take care of the conversion from your image's ppi to the printer's dpi. So you don't have to worry about interpolating the image up to obtain the "correct" dimensions for your printer.

As for achieving the 3:2 aspect ratio, most people simply crop lengthwise to get pixel dimensions of 1600x1067. This yields about 266ppi, which is still extremely good and certainly more than adequate for most purposes, considering the relatively small print size. If you wish to print at 300ppi, you can simply add extra whitespace (or whatever fancy border content you want) to 'pad' the image up to the necessary 1800x1200 size.

 

[mrdogbear]

thanks for everyone comments.

My DC(Olympus C730Z) is able to set each photos in 3:2. Does it mean that I can print the photos directly without editing it? The printer should automatically fit my photos into 4R size paper based on "Midnight" mentioned.

Am I right?

 

[Midnight]

If your images are already in 3:2 format, then you should be able to print directly to your printer. However, you'll have to make sure you set the paper size (4"x6") correctly when you do so.