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Old Mar 16, 2005, 11:09 AM   #1
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My Costco uses the Fuji chemical process to do both roll and digi-prints. My question is do I need to resize my originals if I want 4x6 prints or will they do that automatically based on what I ordered?

The files on my camera are a hodgepodge of different sizea and resolutions (Canon A60). I took some at 1600x1200, superfine, thinking this would get the most out of the camera. This is probably wrong thinking and the 1600x1200 refers to "size" of the print (8x10 I think) and the "superfine" setting tells it how much of the max pixels to use right? (2.1 meg) So a "superfine" photo of any size setting would get the maximum pixels saved?

Now the resize question, I pulled one of the 1600x1200 pictures into Paint Shop Pro and tried to resize to a 4x6 print at 300 ppi. The photo info now says image is still 1600x1200 at 5.33 x 4" with 300 ppi. So now I think the 1600x1200 is just the maximum pixel "array" right no matter the print size? What does the "Normal, Fine, Superfine" setting do then? Also PSP says file size in RAM is 5,625K, but the JPG file in Explorer says it's only 225 kb. I'm really confused now!
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Old Mar 17, 2005, 2:43 AM   #2
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Yes, the photo lab will print the images based on what you order. You dont need to do any resizing.
For the best print quality, always use your 1600x1200 (2mp)camera setting, superfine. The superfine/fine/normal settings refer to the amount of compression applied to the jpeg images. Superfine has the least compression and so the best quality, with a larger file size.

However, you may need to do some cropping for 6x4" prints. Your camera, like most, has an image 'aspect ratio' of 4:3 (1600x1200 pixels). 6x4 prints are 3:2. This means that about half an inch needs to be chopped off the top or bottom of the print. You can leave this to the lab, and hope they dont chop off any heads! Some labs will print in the 6 x 4.5" size which retains the complete image. Or you could crop the image yourself in photo editing software.
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Old Mar 17, 2005, 12:34 PM   #3
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Thanks, that makes it much easier!
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Old Mar 17, 2005, 7:15 PM   #4
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What I still don't get is when I transfer pics directly from my camera (2.1M) and they're the max 1600x1200 size and I think some at least are super fine, the file size in Explorer only show a size of 500-700k and not 2.1 meg?
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Old Mar 17, 2005, 8:05 PM   #5
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Rustynuts, you are getting your MEGS mixed up. MEGS or mega, means a million. Like kilo means a thousand. But a million what?

In camera image resolutions the mega refers to megapixels. An image consists of pixels across x pixels down. i.e. 1600 x 1220 pixels = 1920000 pixels (said to be approx 2 megapixels).

With file sizes the mega & kilo terms refer to megabytes or kilobytes. Your resulting image file sizes will vary according to the amount of compression you choose in the camera. As I explained before, Superfine has the least compression & the higher file size. 500-700kb is normal for your 2MP images. The other compressions will give smaller file sizes, and lesser quality.

I hope this is helpful. It could assist you to look for digital camera tutorials that explain these details. I've seen tutorials recommended on these forums. Possibily someone can offer suggestions.
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Old Mar 17, 2005, 8:28 PM   #6
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Steve usually takes his sample photos at best JPG quality and throws in a couple of TIFF or raw for comparison if cameras do that. For reasons I don't understand he used "Fine" for his test shots on the A60. He ended up with 1600 X 1200 shots in the 650k to 1Mb range. Superfine should be larger on average. The lower the quality (higher compression) the larger the difference between pictures. Some images compress better than others.

When you open the image in PSP it decompresses. Without compression a 2Mp image is about 5.5Mb. If you save it from PSP in an uncompressed format like TIFF the file will be about 5.5Mb. That is independent of the compression originally applied to the image – all 1600 X 1200 images open to that size regardless of compression. If your 1600 X 1200 image is 225k in Windows Explorer it is compressed quite a bit to a low quality. Either your camera was set to a low quality or you resaved the image at a low quality. The lower the quality it comes from the camera the more important it is to save it in an uncompressed format after editing or at least in a very high JPG quality. The highest quality JPG from Photoshop for that sized image is around 2Mb. Superfine from the camera should be close to that. They vary according to content, but very high quality JPGs don't usually vary so much as to give a 500-700k image. My guess is that they weren't taken at SHQ or SHQ on your camera doesn't give the very highest quality possible for that image size.

1600 X 1200 has nothing to do directly with print size. It is simply the number of pixels you start out with, and you can put them in as small or large an image as you want. If you get the largest crop for an 8 X 10 you end up with 150 PPI, which makes a decent print – not great but decent. For a 4 X 6 you end up with 267 PPI. 5.33 X 4 gives 300 PPI as you found.

I don't use PSP and don't know whether newer versions let you pre-set the crop to certain dimensions. In the past you couldn't, but they have been steadily improving the program. If you are going to have the photos printed at 4 X 6 it is better to crop them yourself. If PSP lets you pre-set the size use that. If not, this little free program will crop them for you: http://ekot.dk/programmer/JPEGCrops/ It is best to not resample for 4 X 6 prints. There is usually a way to do that in any program and JPEG Crops doesn't resample. The crop is loseless and you can set it to not overwrite the originals – I highly recommend you set it that way.

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Old Mar 17, 2005, 11:52 PM   #7
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Oops! Yes I totally forgot it was MP and not MB!:?
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Old Mar 18, 2005, 1:43 AM   #8
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Fine, Rustynuts... I guess you will get it all sorted.

And thanks Slipe for the the great information. Almost more than Rusty needed to know!.

But the link you gave for Jpegcrops is great. Many thanks. I have tried it, & it will be very useful.

Rusty: I'd suggest you grab the Jpegcrops from the link that Slipe gave. With that, you can crop one or more images to any print size. Good luck.
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Old Mar 21, 2005, 7:34 AM   #9
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PSP's crop toolwill let you crop for both aspect ratio and composition using a drop down list of common print sizes.


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