PShop Wizards.. BEST way to save a Jpeg??

I am not sure if this is the right place to post this or if it has been asked before..

To all Photoshop wizards.. What is the best and high-quality way to save a Jpeg, probably to upload to web, but also to look great when opened??

I have seen some planet shots by NASA before.. The jpeg files on the web were tiny, but when opened, the quality was fantastic and the size grew to massive proportion, so they knew what they were doing..

For the above question, i mean:

- Smallest size, but best quality..

- Best dpi

- Best mode, bits, colours

- Least noisy

- Baseline optimized etc..

- Anything else that i haven't thought of..

Go for it..Happy 2011 to all..

In general the smaller the size the lower the quality, however the relationship is not linear. In the area of the high quality numbers (9-12) the increase in quality as the number increases is marginal but the increase in file size is substantial. Probably 9 is the best compromise between the two parameters.

Absolutely irrelevant to web display, has no effect on image.

All jpgs are 8 bits; you don't get to choose. sRGB color space until the day comes when everybody has wide gamut monitors or all browsers are color managed.

Strictly speaking camera generated noise is independent of image format; however, excessive jpg compression can create noise-like artifacts. Any level above 7 should be safe from this.

This is not an answer to the post above, thanks for answering though, just trying to explain myself a bit better..

I have been using PShop for ages and i know about saving in 1-12 and maximum quality.etc..

It's more, as in the NASA pictures, the relationship between the 72 dpi and the proportion to the saved size and how amazing the quality and size they were when opened..

Just thought, they were doing something i didn't know about..

I'm not clear on something -- are you talking about in image that displays as small and then when you click on it "opens" to a larger, higher quality image? Various Web hosts allow you to upload a large high-quality file and then compress the images to a "normal" viewing size that you can choose to view at full size (or other sizes).

The 72dpi has absolutely no bearing on the proportion of the saved size. Below are two versions of the same image. Both images measure 750x500 pixels. The top one was saved with an embedded resolution of 72dpi whilst the lower one was saved at 300dpi.

If you can see a difference between the two images, you've got better eyes than me.

No..

I am not talking about a Web Image 'linked' to a Higher Res image from a server..

These NASA images, i think some Telescope sites do it as well.. I just pulled the jpeg to my desktop and it was a tiny file like 250k or something..

Checked it in PShop, it was saved as 72 dpi, but then when i looked at the dimensions above in cm's, they seemed really large.. When opened, it was a beautiful, crisp image, almost like a Tiff, no noise,nothing..

It looked like, they got some sort of 'Proportion' thing right between 72dpi and Dimensions... Meaning, really small file to download but amazing Quality when opened..

I hope i am not getting myself in knots here.. I was just wondering if there's a nice trick like thisto save Jpeg's as really good quality but small as well..

Without looking at their site, I can't imagine or work out what they are doing from your description. Sorry that's not much help to you.

Thanks for trying to help... Strangely your second image opened up as '3000' dpi in my PShop... Quite impressed with the small size though..

These are the sort of images i mean, don't worry, they are there to DLoad, so nothing illegal...

http://www.nasa.gov …-2008-28-a-print_full.jpg

I think they are doing something to the 'Pixel' sizes, rather than 'Dimension' or 'Dpi'....

That link opens to a "small view" image -- 561x449 pixels. When you click on the image it opens the "full size" image of 3000x2400 pixels. And, if you look at the properties of either, they both show the same file, the one for the larger image. So, that's what you get -- the smaller is a link to the full-size.

Just a guess, but I would imagine that NASA took those photos with something slightly better than say, a 300D with the kit lens. Could that have something to do with the quality?

ChasP505 wrote in post #11558015
Just a guess, but I would imagine that NASA took those photos with something slightly better than say, a 300D with the kit lens.

I will have you know, that this statement has put an image in my head of the large, majestic Hubble Space Telescope drifting in space, with a Rebel duct-taped to the end of it...with the flash extended.

This may have no bearing on the topic, but these images were more than likely taken with a high res CCD imaging system. Very long exposers and more than likely multiple images stacked on a camera that you and I would never ever be able to afford let alone launch into orbit where you are not dealing with atmospheric condtions that we are subjected to here on earth.
That said, you can obtain some nice images with a properly balanced and polor aligned auto tracking scope and a Sbig CCD camera. http://sbig.com/ not a cheap hobby though. You can do pigy back with a CMOS sensor but you will not get the same results.
I have a pier mounted 8"Meade LX 200 in a roll off roof observatory in my back yard, howevr I sold my older ST-7 CCD camera awhile back.
OP are you interested in astro photography or just the ability to link these types of images? If its astrophotography a good site to visit is http://www.astromart.c​om/
Lots of good info on the fourms and used equipment can be had here.
Hope this helps

tonylong wrote in post #11557684
That link opens to a "small view" image -- 561x449 pixels. When you click on the image it opens the "full size" image of 3000x2400 pixels. And, if you look at the properties of either, they both show the same file, the one for the larger image. So, that's what you get -- the smaller is a link to the full-size.

My apologies, Tony..

It didn't seem to me, that there was a link there.. Well done..

The Shaheen wrote in post #11557528
Thanks for trying to help... Strangely your second image opened up as '3000' dpi in my PShop... Quite impressed with the small size though..

I think they are doing something to the 'Pixel' sizes, rather than 'Dimension' or 'Dpi'....

You're right, it is 3000, but that proves my point. The embedded DPI figure in an image has no bearing on how it is displayed on the web. What matters when it comes to web display is the size of the image measured in pixels.

Ugly Joe wrote in post #11558083
I will have you know, that this statement has put an image in my head of the large, majestic Hubble Space Telescope drifting in space, with a Rebel duct-taped to the end of it...with the flash extended.

LOL