JPEGmini files

[IanB]

http://www.slrlounge.com/jpegmini-reduces-file-size-5x-no-perceivable-reduction-quality/

what are your thoughts? smaller files always interest me.

I seem to be filling up disks with big files; raw + edited psd/tiff that will most likely will never see the front of a screen again

Once the main editing is done I do find it hard to justify keeping raw/psd/tiff files instead of jpg files, and jpegmini sound even better if I save 20 inch images 'just in case'

[Graham_of_Rainham]

Re: JPEGmini files

Looks interesting. I shall have to try that.

[Jim Ford]

Re: JPEGmini files

Hmm - I just wonder how much he knows about image files, when he talks about printing a raw file or using it in an online gallery!

Jim

[Imageryone]

Re: JPEGmini files

What you have to know is that ANY Jpeg deteriorates every time you open it, not very good in the long term!

[Otto]

Re: JPEGmini files

I think just opening and then closing a jpg doesn't affect it, but editing and/or saving it again under a different name may reduce quality.

[Ulfric M Douglas]

Re: JPEGmini files

This is a bizarre and false statement and should never have been written!;

What you have to know is that ANY Jpeg deteriorates every time you open it, not very good in the long term!

Otto already refuted it more kindly than I.

Back on-topic : storage space is now so cheap per unit that any new reduction codec is irrelevant to Jpeg=type formats. Something out of it's proper time I reckon.
Perhaps it is aimed at the newer small animation formats ...

[IanB]

Re: JPEGmini files

Come on; let's be polite. A lot still believe opening and closing a jpg file will damage it and we should only use TIFF or similar files

there seems to be a lot beliefs from the early days of digital photography that are rather outdated by the gear and techknowledgey we have available today.
Took awhile for me to understand the expose to the right when I had been the taught it's best to expose to the left so there is plenty of data to edit in the whites when using 6 mb D100 nikon. LOL soo much has charged!!

I did a test with a jpg file by opening and saving 10 times in PS and there was bugga all difference in quality when being saved at 12/max quality
Bit like the quality freaks who send massive tiff files to the printing lab; many labs usually convert them to jpg files .

And the mathes involved with the blah blah blah to get a 12 x 16" photo printed. One lab (+ photography business) in aust who printed 12 x16 had a max of 5 mb files. I sent in a couple of 1.5 mb files and received great prints back.
Now that's not saying that a photo printed from 5-10-15-40 mb tiff file would not be better. The photo I received was acceptable to me and the client. IMO the only way anyone but a qualified expert would tell the difference would need to put the photos side by side.

Why do we feel the need to keep forever our original raw file, + the PS layered filed + a tiff file?

One thing I do agree with is when capturing with jpg only we should work only on a copy of the original file. But it's less of a drama these days when we use programs like LR for the bulk of our editing; but then why use not use raw?

[Imageryone]

Re: JPEGmini files

Sorry if I upset anyone, but I just repeated what I was taught by Adobe back in the day.

From the Adobe Photoshop Training Manual that I was taught

" a lossy compression system ( a system that selectively removes data from the file). It is a popular format for Web publishing because it can produce small files, but each "save" results in further compression and files will deteriorate quickly.
Use JPEG as a web format but never as a working format. Always work on a copy of the original. "

All things change with innovation, and the above may no longer apply, and , if so, my apologies for my ignorance.

[DerekW]

Re: JPEGmini files

the key difference in the above two posts is the use of the words
Close
Save

They are not synonymous

[OM USer]

Re: JPEGmini files

I did a test with a jpg file by opening and saving 10 times in PS and there was bugga all difference in quality when being saved at 12/max quality

I think Ian's statement sums it it up. There is a difference (and the difference is in a loss of quality) every time you save a jpeg but the difference is very small and you are unlikely to notice it. The loss of quality arises because you can not edit a jpeg directly but it has to be converted to an image bitmap to be displayed on the screen (which uses discrete pixels) and the save process re-encodes that bitmap loosing some quality on the way. Becuase of the small loss of quality when you saved it, upon reopen the resultant displayed image bitmap is very slightly different from the image bitmap that was encoded and saved, hence the slight gradual loss of quality every time you save and reopen. However open, edit, save, edit, save, edit save will not result in gradual loss of quality as you are not resampling the new jpeg at each stage.

I also agree that there is no reason these days why we should be using a lossey compression system.

[Jim Ford]

Re: JPEGmini files

Took awhile for me to understand the expose to the left when I had been the taught it's best to expose to the right so there is plenty of data to edit in the whites.

Huh!

Where did you get the idea to "expose to the left"? Most of the data available for the image is in the brightest stops. To expose to the left is to lose this data and risk posterisation.

Jim

[IanB]

Re: JPEGmini files

Huh!

Where did you get the idea to "expose to the left"? Most of the data available for the image is in the brightest stops. To expose to the left is to lose this data and risk posterisation.

Jim

Edit : I have totally stuffed here and should have said EXPOSE TO THE RIGHT ..ETR

expose to the left [should read expose to the RIGHT ] as much as possible and without clipping any h/lights may have been a better way to explain how I understand it now Jim.

The idea is not to have any more blacks than we have to as the blacks will often contain noise. And the smaller the sensor the more important that seems to be.

Things I got away with when using the ff canon 5d2 can't done with our smaller sensor and certainly cannot be done with cameras that have tiny sensors. In many way; those using the tiny sensor cameras need to be better photographers IMO. I learnt that when I was using only panasonic fz200; great camera but only as good as the driver

If the blacks are clipped too much while not clipping the lights we need to consider hdr or manually bending two files in PS; however I have found the oly files very good when it comes to rescuing black areas

Being able to see in the viewfinder a live histogram and how the subject will be record has to one better things about the modern (non-DSLR) cameras like the; our olys.

[Jim Ford]

Re: JPEGmini files

expose to the left as much as possible and without clipping any h/lights may have been a better way to explain how I understand it now Jim.

The idea is not to have any more blacks than we have to as the blacks will often contain noise. And the smaller the sensor the more important that seems to be.

But if you expose to the left, you are increasing the blacks - you're pushing all the data towards the black end of the histogram! Are you sure you don't really mean that you should expose to the right (without clipping the highlights, of course)?

Jim

[IanB]

Re: JPEGmini files

; sorry my bad everything. Always pays to read my signature

you are right Jim; I did mean to the RIGHT folks; very sorry for the confusion I have caused to anyone new photography or trying to understand exposure. It's hard enough without finding such a stuff up in a forum such as this.

Thanks for pointing out the muck up Jim; pity we are in opposite world time zones; the mistake could have be fixed earlier

[ian p]

Re: JPEGmini files

I was always taught "Expose to the light!" and you keep everyone happy.