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Thanks useful information: 10
Are you converting at full size and full image quality or reducing the size and image quality to post the photos on places like this?
Threadstarter
Happens in all software. JPG is a lossy file format. Lossy means that it loses data. JPG was invented back when internet speeds were sloooowww. It was created as a way to reduce the filesize of an image to allow it to be transmitted over the internet. The aim was to create an image file that was small in size (KB) to allow it to send over a 14.4kb or a 56kb modem without it taking ages to do so.
How they did this is that they use a smart mathematical algorithm that looks at each pixel and the ones around it, using this smart algorithm reduce the data in the image file, to make the file smaller. Now what happens when you have a cake and need to fit it in a box that is too small. You cut it up and fit as many pieces as you can in the box. it is still a cake, but it is missing bits. This is exactly what JPG does.
So all those missing bits are the sharpness, or the slight naunces in colour changes from one pixel to the next. Yes you still have an image, but it is missing some bits.
So that is why when you save as JPG you always lose something.
You can see the extreme of this by saving an image as a JPG, then opening that new image and saving it again as a JPG (new file name) and then open that new image and save it as a JPG with a new file name... and repeat. After several saves, you will really start to see damaging image degradation. You do not notice it as much with the first save, but the image degradation is there.
"It is one thing to make a picture of what a person looks like, it is another thing to make a portrait of who they are" - Paul Caponigro
Constructive Critique of my photographs is always appreciated
Nikon, etc!
RICK
My Photography
I don't think this should be happening. It doesn't happen when I convert to jpeg. I suspect that some of the conversion parameters are wrong or there is some difference between the way it is displayed before, and the way it is displayed after.
^Same here. At least not to the extent you imply.
Some salient detail would be needed to give a proper reply, and this could be a very useful exercise for others.
Can you do a couple of screen prints of your processing in DPP? Typically, one that shows the settings you are using
in DPP with the image (looking its best).
Also, post up one of your "bad" results.
Point out some of the shortcomings.
I suggest you use Flickr to link them here so that we can see them at a large size.
Ta.
Am.
CC, Image editing OK.
Threadstarter
Looking... OPen the raw image in your raw converter (?DPP) and take a screen print of that.
- - - Updated - - -
Poorman. Three of those four shots certainly look fuzzy in parts. It's hard to tell why, missed focus?, depth of field problems?...
I cannot raise any EXIF to see the exposure settings. The two HK Holdens and the first RED drag car are iffy. The 2nd red drag car is
Can you post up some exposure details, and for the 2nd drag car, a screen grab from DPP of the raw file?
Threadstarter
not sure how to do a screen shot mate ....
Screenshot. On a PC. ALT+END (usually has prtsr) on it. Then open your editing software, new document, from clipboard, then paste.
On a Mac. Command+Shift+4, then use the mouse to drag around the screen to get what you want captured. Let go of the mouse. The screenshot will be on your desktop.
Last edited by ricktas; 02-12-2015 at 7:47pm.
Sorry! Was having tea (then washed up).
Yep. Get your normal editing screen up (any screen can be "captured" to Clipboard).
If you want to show any particular editing function just open the function dialog box - like
"sharpen", tonal controls... etc...
When you have the screen you want to show, then for Windows,
- do a Shift-PrtSc (that's "Print Screen").
It will then be in Clipboard. Open Photoshop/Elements etc, then in either of those,
-do a File - New, or do just a Ctrl-N.
You will see a dialog box open with the default size of your screen.
-Hit Enter, and then do either
-Edit - Paste, or Ctrl-V
Your screen capture will appear in the new document. Finally, in Photoshop/Elements
-do a Layer - Flatten image, then save as a jpeg.
If this is too confusing...
1. Apologies.
2. Let me know.
Once you get it, you'll be laughing. It will also help clear things up.
For screen shots in Win 7, the Snipping Tool is easier to use. Then you can just draw a rectangle around the bit on the screen you want to capture, and it automatically pops up a window with the piece you want on it. Then there is a save icon to save the result where ever you want. To access the Snipping Tool, go to the start button, and then in the search box type "Snipping Tool". To be honest, I just have to type "sn" and the computer offers the link to the Snipping Tool. You could always put a short cut to the Snipping Tool on your desktop. It is a pretty handy tool.
I too, find very little difference between the raw file and the resulting jpeg. Like Steve, I wonder if you have your settings, which output the jpeg from the raw, adjusted incorrectly. Make sure you have the quality for the jpeg set to it's best setting. That would be the first place I'd look. Make sure the jpeg quality setting is not at 3 or 4.
I don't use DPP to convert to jpeg. If I use DPP, I pass the raw file as a TIFF into Photoshop. If I want a jpeg, I use photoshop to convert the tiff into a jpeg.
I have never experienced what you described - generally outputting a converted RAW into JPEG results in an image that looks nearly identical. However, it does depend on your compression settings in whatever software you are using. I'm not using Canon so I can't say how that works. Make sure your quality setting is at 100%.
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