How important is it to know (what they do) and understand file formats in Photoshop?

[ChadPT18]

Hello all,

Was just wondering if you could give me any advice on file formats when importing or exporting in Photoshop/when receiving or sending off anything required for photoshop.

I have done a lot of my own research on the topic but still get confused with JPEGS, DNGS, RAWS, TIFFS etc.

I am still a beginner and the last thing I want to do is send a file in the incorrect format to a client.

Any sort of advice will be of great use.

Thank you in advance.

- CT

[melissapiccone]

DNG and RAW are both raw formats and you will never send them to a client. You will convert them most likely to jpg. They are your "negatives". Unless someone specifically asks for a tiff, probably no tiffs, either. Jpgs are your friends to hand off. What do you do, what are the files you are sharing?

[ChadPT18]

Hello Melissa.

I generally send JPGs when a client has asked for a quick look at an image so they can get an idea of how things are progressing.

I will normally send TIFFs as final delivered files unless the client has asked for something else.

[Mohit Goyal]

Hi ChadPT,

Please refer the below articles, which explain you the major difference between all file formats used in Photoshop.

File formats in Adobe Photoshop

How And When To Use Different Types of Image Files

Hope it helps.

Regards,

Mohit

[gener7]

This is a good thread to look at: PNG image quality superior to JPEG?

D. Fosse pointed out something I never even knew: Tiff is best for (usually sent out) commercial printing above the others because it can handle the CMYK printer profiles needed for this work in order to get consistent color. Jpeg and Png are best for web.

[D Fosse · Accepted solution]

Yes, PNG support for icc profiles is unreliable. Jpeg supports profiles reliably, and it also supports CMYK in the format specification, although not always in many applications' jpeg decoding. 

Jpeg is usually fine as final delivery format, provided you don't edit and resave it multiple times afterwards. Jpeg data compression is destructive, irreversible and cumulative, and quality degrades with every resave. Never use jpeg as a working/archive format.

The reason jpeg is still widely used, is that the compression is incredibly effective for reducing file size - shrinking a file to, say, 2-10% of original size with little visible quality loss. This can be important for online delivery.

If image quality and integrity is critical, e.g. for high quality print, jpeg is risky. For this, the standard interchange format is TIFF. Much bigger files, but no quality loss whatsoever.

PSD is the native Photoshop format, and the only one that supports all Photoshop functions.

A raw file - many proprietary formats, CR2, NEF etc - is not something you will ever send away. That's the "naked" sensor data from a camera, and it needs processing in a raw processor to become a useful image. Not to be confused with Photoshop .raw, a very specialized format that is almost never used.

[gener7]

https://forums.adobe.com/people/D+Fosse  wrote

PSD is the native Photoshop format, and the only one that supports all Photoshop functions.

There used to be more than a few "Tiff is no different than PSD" threads.

So what Photoshop functions does Tiff not support? I want to put this to rest.

Gene

[D Fosse]

To be perfectly honest, Gene, I can't remember    But I'm pretty sure there was one or two things...anyone?

I'm using PSD as master file format mostly out of habit. In practice PSD or TIFF doesn't really matter. Master files aren't going anywhere anyway.

[gener7]

Same here, D. I prefer using the designated native file format for the master. Less surprises that way.

[rob day]

So what Photoshop functions does Tiff not support? I want to put this to rest.

InDesign lets you turn a PSD's layers on and off via Object>Object Layer Options... —no need to edit the original.

When you save a PSD you don't have to edit the cryptic and geeky Save As dialog—LZW, Interleaved (RGBRGB), Byte Order, etc.

With TIFF you have to check Save Transparency for transparency to be honored in InDesign. PSDs are automatically compressed (lossless) and you don't have to worry about its transparency in a page layout.

Yes, PNG support for icc profiles is unreliable.

Yes, that was a problem with older versions of InDesign, but I think it was fixed starting around CC 2015. Earlier versions of InDesign ignored PNG profiles, they would always show as Document RGB in the Links panel. The current version correctly honors a png profile.

[D Fosse]

PNG profile support is still inconsistent in Photoshop.

Save For Web correctly embeds the profile, no problems.

However, Save As png strips the profile and there's no way to embed it:

When you open that file, you get this -

- which is obviously nonsense since Save For Web manages it just fine.

[rob day]

I wonder if that's an OS problem? On OSX if I open the Save As... png I placed in InDesign, Photoshop shows the correct assignment:

OSX's Get Info also shows the profile:

[rob day]

This is OSX's Save As...

[D Fosse]

OK, then it behaves differently (and properly) in MacOS. This should be reported as a bug in the Windows version, if it isn't already (I don't watch the feedback forum).

The really funny thing is that it was once the other way round - if you wanted to embed the profile in a PNG, you had to use Save As. Then for a while they both worked, and then at some point only SFW would embed.

[jbm007]

Often it also is determined by the type of camera you use and the format the camera uses.

camera raw files are the best format to work in, but they are often large in size.

convert ing images to dng gives you more flexibility in case you camera or format is no longer supported.

In all honesty you should be looking at the use of color management in your workflow.

That in the long run will be more important then which file format you settle on.

JMTW

[ChadPT18]

Thank you to all who posted. Very interesting and informative!

[Per Berntsen]

I have hardly ever used PSD because Tiff is the "industry standard", and I believe there are more applications that can open tiffs than PSDs. Tiff compression is also more effective than PSD compression, but I didn't know by how much, until I did this test:

An 8-bit tiff saved with LZW compression (lossless) is less than half the size of a PSD. LZW does not work well with 16-bit files, it can actually increase the file size.

The 16-bit tiff with ZIP compression (also lossless) is less than 10% smaller than the PSD, but it's still a reduction in file size.

The amount of compression will vary with image content, and for the record, here's the image I ran the test with.

[D Fosse]

OK. This is down to personal choice. To me, the main thing about master files is that they never leave my machine. So standards are irrelevant to me as long as Photoshop can work with them.

With a 5.5 TB archive and growing, plus 2 backup sets, I might start to worry about file sizes at some point. These 10 TB enterprise disks are pretty expensive

[ChadPT18]

"The amount of compression will vary with image content"

When you say this are you referring to how large or small the files are, or are you insinuating the amount of colour in an image could maybe impact the compression etc?

Thanks Per.

[rob day]

Both TIFF and PSD do some lossless compression, so repeating pixels would have an affect. These images are both 24-bit at 3000x3000 pixels, but there's a 40X difference in the saved file size—25,497KB vs. 629KB: