Mike Chaney's Tech Corner

Gentlemen,

I am having a difficult time distiguishing the image quality of a well exposed RAW image when processed and converted to TIF and to 100%-JPG using the same image processing software.

My main objective is to view the images on a HD 50" LCD TV through direct reading the digital images from a SD card.

This is very relevant to  me because the JPG images take a lot less space in the SD card with no apparent image quality loss.

Can anyone please comment and provide their experiences?
Thank you,
Persio.

Unless you use a JPEG that is much more compressed, you're probably not going to be able to see a difference.  JPEG should be fine for what you are doing as the main issue with JPEG saving is generational loss where you save over and over.

Mike

Mike, thanks for your comments.
Persio.

Honestly, I'd just shoot RAW unless there's a compelling reason to do otherwise. While you do save compression losses by doing that, there are a couple of other good reasons to do so.

I've noticed that I need that extra head room, I tend to shoot outdoors almost exclusively, and having the extra stop or two makes it much less likely that I'll lose detail to blown highlights or lost shadow detail. A proper exposure often times involves giving up detail on one side or the other, raw helps me limit that somewhat. And it allows me a little bit of wiggle room if I want it to be somewhat between stops.

I've also noticed that for some sorts of images you'll lose the yellow, red at the high end unless you under expose. Basically choosing between exposure and proper color, not a decision I like to make in the field.

You've since you've got all the color information there, you can decide whether or not the camera's being faithful to your vision, rather than the other way around. This may or may not be important, there's definitely something to be said for guessing what the camera's going to do, but you can always opt for that later on.

Additionally you can make an informed decision about how much sharpening to apply when you're sitting in front of a full sized monitor rather than hoping that the camera will get it right, this will very somewhat depending upon the type of photography and gear, but you can see the results rather than trying to second guess the camera.

Hope that helps somewhat, there may well be no apparent image quality loss, but unless you start working with the RAW files you're not likely to notice what you're not getting. At least with RAW you can change your mind later and go for the quicky auto conversion.

With Qimage SE raw processing not only can you go for the quick "smart" (better than auto) processing, you have the quick refine and no conversion, just print from raw.
Maybe that what you meant anyway?
Terry.

I should have added: RAW files do always have a decent jpeg embedded within them, at least half size. You don't have to select raw+ jpeg on your camera to get it, just raw is sufficient.
Qimage SE can extract this embedded jpeg with just a (right) click with images in the queue. It provides an immediate comparison with your raw image  8)
Terry.

Not quite, the camera that I've got experience with allows you to extract the JPG from the file itself as exactly what the camera would have done. There are additionally programs that will regenerate the JPGs on their own or duplicate the conversion.(And yes that's probably much closer to your next post)

Generally though, I'll take this position, I'll use Qimage SE to handle it in that fashion and tweak if necessary. But the main point of my post was that you get to decide after the fact while looking on a full sized monitor instead of hoping that the camera got it right. Bonus points for times when I learn a new post processing technique to make previous shots work better.