JPG quality

[lazuras_dc]

When saving JPG, does changing the "quality" to make the file take up less memory affect the actual image quality? Do you always max it?

[ldelacruz]

Yes. Depends on what your using it for and how many times you resave it.

[Peacock]

I always max it, but I am processing from a raw file. But yes everytime you open and resave a jpg you will lose some quality.
I thought I read somewhere that a JPG file becomes usable after about 25 saves. Haven't tried it myself...hmmmm weekend test! LOL

[lazuras_dc]

I go from RAW too, from Light Room i do some exposure, WB, then to JPG, open in PS (since i'm more familiar w/ it) i do other stuff but I didn't know everytime you edit it takes some quality away. That's good stuff to know!

[Kev]

Originally Posted by Peacock

I always max it, but I am processing from a raw file. But yes everytime you open and resave a jpg you will lose some quality.
I thought I read somewhere that a JPG file becomes usable after about 25 saves. Haven't tried it myself...hmmmm weekend test! LOL

shouldn't that be "unusable"?

[MicWayWal]

JPG is a space saving compression of an image file. When you save it as a jpg, the engine samples the pixels of the image, groups pixels together depending on what you set the compression to be, then makes all the pixels the same for the group. If you take a jpg file you have already saved open it, then save it directly again, it will be making a bigger group of pixels to save and therefore lose quality in the next save. I can notice a big difference after two or three saves.

If however you perform a Save As function instead of a save, you are taking one saved jpg and making it the save for only the second time. You can do this over and over because in effect you are saving it to only the second generation again and again. But you do lose the files progression and there is no going back.

I always save my work as a PSD file. Then when I am finished I save it as jpg to send to the lab for printing. If I need to rework the image, I go back to the PSD rework it, save the PSD, then make a new jpg file. So ALL my jpegs only have one compression when saved.

[Redneck]

Originally Posted by MicWayWal

I always save my work as a PSD file.

Wow, that must take a lot of space on your hard disc. How do manage this problem?

[CaptainTom]

Originally Posted by Redneck

Wow, that must take a lot of space on your hard disc. How do manage this problem?

with 1TB drives going for $139 storage is not a factor. If image quality is a concern, don't degrade your image.

[Redneck]

Yeah, but how many external drives do you want to have?

A RAW file has about 15 MB, a JPG maybe around 10 MB. When I save it as a PSD files, it comes down to something between 40 and 100 MB. So with just one picture you might need up to 125 MB. Shooting a wedding with 500 images might take 50 to 60 GB. That's a lot of space. You basically would have to buy a new external drive every couple of months (besides storing the old ones somewhere).

[CaptainTom]

If you are only going to use images on the net then just shoot them in .jpeg and you're done.

If you want to work on the images to make them something special and marketable (not what everyone needs) then you shoot RAW , process in LR or PS, keep the layers via PSD, convert to .tiff and save it all.
I just opened up a new HD (1TB) and expect to buy another to have when this one fills up.

If you were a car mechanic you could get the job done with a $100 tool set from PepBoys, or you could get some real tools and do the job easier.

The once a year mechanic only needs the PepBoy tools.

[Redneck]

I completely understand where you are going.
However, what practical use do you have for a huge PSD file after you've presented and delivered the proofs to the client?

I mean do you really work on your images all over again after you've completed the job?

[CaptainTom]

Originally Posted by Redneck

I completely understand where you are going.
However, what practical use do you have for a huge PSD file after you've presented and delivered the proofs to the client?

I mean do you really work on your images all over again after you've completed the job?

Good question.
The value of having the .psd file is that if for any reason I wanted to alter the image (a new plug in, or learning a new trick) I don't have to go back and start all over again. I have the .psd file with all the layers, etc. intact and I can modify a single action if needed. I.E. the image is given to the client and a couple of months later they call and say they'd like another copy, but could I convert it to B&W or could I change the background color. It's easier and gives a more professional look if you can work on the specific layers.

It's like recording a sound track. If you toss all the tracks after the recording, you can't remix if needed.

[Redneck]

You know, I totally agree. It is really really nice to have the PSD file, gives you some peace of mind. But again, the cost for having something you'll probably never ever touch again, is pretty high.
It's a totally different story when you shoot for your own use (family pictures etc.), but for clients ...?
I don't know, I haven't done as many jobs as the old school photogs here, but I've never had the case that a client got back with me and wanted some changes to the images done after delivery.

[CaptainTom]

I've got images that I shot several years ago that could be in my current portfolio if I reworked them with the tools and skills I've developed over those years.
I'd hate to have to start from a .jpeg file that I saved.

Oh well, this horse is dieing and needs no further beating from me.

Good discussion. Somebody else may have another idea.

[Redneck]

Yes, I've enjoyed the discussion as well.
But as you mentioned, we are all developing our skills over the years and we would do things probably different today than we would've done them a couple of years ago.
So I would probably start all over again from the RAW file anyway.
Just saying, my file storage workflow only includes the RAW files (all of'em, even the ones I chose not to process) and the completely processed JPG files. Of course everybody may handle this different. Just my opinion.