Different quality with same # of pixels?!!

Ffirecracker · Oct 17, 2009

Hi, I'm new on this board, I'm sorry I'm going straight to the question, will introduce myself tomorrow.. it's late here, past 1 AM.. so here it is. I have taken lots of pictures with my camera (Canon 8MP), that look great on the screen even zoomed in AND prints clearly too. However, I just received my wedding photos, and some of them are low file size but enough pixels, and others from a friend who also took pics, and have also enough pixels & big file size, yet both look awful on the screen when I zoom in to try to edit! I tried to print one out and (the smaller file size) and it looked even worse! Why is that? What determines the quality of the photo? These people btw have better cameras than me

silentfallen · Oct 18, 2009

If i am not mistakes the file size can be affected by allot of things. But the main one i think you are looking at is the "Quality" output. The pixel dimensions can be the same in 2 different photos but the quality can be turned way down in one causing the lower file size. Like when you are saving something out of Photoshop as a jpg and theirs the Quality option.. if you turn that down it will make the file size smaller by removing what it thinks are "unneeded" pixels in the images lowering the viewing/print quality but it will remain at the same pixel dimensions.

Unless you are referring to the Raw images, then i do not believe what i have said applies.

This is how i understand it works. All tho i have been miss guided before.

Ffirecracker · Oct 18, 2009

What if pixels are high in the photo, and file size is yet it still zooms & prints out pitifully? That's what's boggling my mind.. I've worked with my photos before with lower file size, but still when zooming for editing & printing, results were as clear and sharp as can be. I thought I had it figured out but I guess I still have a lot to learn ha ha.

silentfallen · Oct 18, 2009

post up an example for us to see ..

EDIT: a non edited example ...

Ffirecracker · Oct 18, 2009

Hi, hope this works.. the first is a photo she edited, the second is the same photo unedited, and the third is just a picture I took with my cheap 7MP camera (point & shoot). Thanks so much!

Oops, don't know how to do this, clicked on 'insert image' and it only allows my to put a url..? My pics are on my drive.. and on facebook only.

syphlix · Oct 18, 2009

use something like imageshack or photobucket or something like that

tom123 · Oct 18, 2009

The number of pixels is one thing, the quality of them is another thing. If you increase the number of pixels and don't increase the size of the sensor chip, then you overcrowd the chip and the quality of pixels goes down. This is one thing. Also, if you shoot from hand and not tripod, the camera shake may be causing your problem.

silentfallen · Oct 18, 2009

but camera shake would not make the file size smaller for 2 images that are the same pixel size..

As for posting a photo.. sign up for Image hosting, free photo sharing & video sharing at Photobucket or ImageShack® - Image Hosting for free image hosting.. then you can link the photo to here from the hosted site.

Ffirecracker · Oct 19, 2009

Hi, thanks guys, I have uploaded a few examples here: Pictures by Ffirecracker68 - Photobucket

The first one is one of the photos from the photographer,
The second is a similar one but has been edited

When printing (the edited one anyway), it is not sharp at all

And when zooming in for editing, it is really grainy.

Now the 3rd was taken by a friend, they seem to have more pixels & larger file, but when I zoom in, it's grainy

The 4th one taken by another family member, also seems better, but when I printed it out (in 3.5 x 5) inches, it came out really grainy.. now how is that possible!

The last one, is simply a pic I took with my cheap old canon 7MP, and when zooming in AND printing, flawless. Why? What is it that makes some look ok & print bad, or vice-versa, & others come out perfect.. and they seem to have similar file size.. I'm at a loss here, tried to find the culprit or common denominator, but I guess my knowledge is way too limited.

I would really appreciate someone explaining this to me, and whether or not there is something I can do differently with the pics that i have received from the other people?

Thanks

Rachel

ErectedGryphon · Oct 19, 2009

This might help you understand the sensor relationship part of your question:

Digital Camera Sensor Sizes: How it Influences Your Photography

As for the "When printing (the edited one anyway), it is not sharp at all", more than likely its Quality reduced jpg, edited, then saved as quality reduced jpg. Edit and save enough times and you will be left with a blob. (slightly exagerated, but you get the drift)

P.S. Editing and printing/distributing/posting another photographers photos is dangerous territory, make sure you have permission first!

Ffirecracker · Oct 19, 2009

Thanks, I have written permission from my photographer, the others are from our friend and my m-in-law. I guess the sensor size is something I want to learn about before taking pictures right.. but how about the pictures I already have that were given to me by other people? Some of them have the right # of pixels, like originals for example (non-edited), but still zoom & print grainy. That's what I don't get.

ErectedGryphon · Oct 19, 2009

More than likely it has to do with the quality/compression level, of the file.

Here's a quick explination, you may want to research further, if this is not enough;

JPEG - Wikipedia, the free encyclopedia

silentfallen · Oct 19, 2009

Thanks for the good info ErectedGryphon..

As the the photos that you hosted, it looks to me like they are all out of focus, if i save them and zoom in they are bad quality. I would be asking for the originals. If he tells you they are the originals it would be the first time I've seen a high quality jpg at 800kbs file size..

ErectedGryphon · Oct 19, 2009

silentfallen said:
Thanks for the good info ErectedGryphon..

As the the photos that you hosted, it looks to me like they are all out of focus, if i save them and zoom in they are bad quality. I would be asking for the originals. If he tells you they are the originals it would be the first time I've seen a high quality jpg at 800kbs file size..

I hope that's directed at firecracker, if not please let me know which of my photos your discussing.

If they all are, then I say to you, they aren't out of focus, they are focused for my eyes :lol: