Blank layer help

[bkuhl]

I recently read a post, that I cannot now find, that talks about decreasing file size by using "blank layers" instead of a copy of the layer below. I am grateful for this tip and understand about painting etc on this new blank layer, but the post mentioned an option to "sample the layers below" which I cannot find anywhere.

This seems like such a simple technique to better use layers, but I think I might be missing something to make it even more useful and memory efficient.

Thanks is Advance for the Assistance.

Cheers.
--
Mighty EEE OH's Twenty Dee
Pbase Supporter
Proud FCAS Member! #56 (with CP5700)
http://www.pbase.com/billneve

 

[JJMacks]

Open an image file and you have one layer the background layer. If you save that image in PSD format it will have some size lets call it size x. If you copy the background layer layer you have two identical layer you have doubled the number bytes in memory. If you change the new layers blending mode to screen you will see the image lighten. If you nod save that as a PSD file you will see that the files is now Size 2x.

If instead of copying the background layer you just added an empty adjustment layer like levels you need not mane an adjustment even. That layer has no image data it has just a bytes containing the adjustment settings. If you change the adjustments layer blending mode to screen you will see the image lighten just like when you changed the copied layer's blending mode. Save this image as a PSD file you will see its file size will be much less then size 2x.
--
JJMack

 

[bkuhl]

Thanks, but I am very comforatable with my understanding of adjustment layers.

I thought I had seen someone talk about a blank layer that could then be used to make other adjustments on. I could easily see painting etc... on this new blank layer, but I thought the post said something about being able to sample information from the layers below it, say for the clone stamp, healing brush etc...

--
Mighty EEE OH's Twenty Dee
Pbase Supporter
Proud FCAS Member! #56 (with CP5700)
http://www.pbase.com/billneve

 

[cspringer]

Don't know about that...are you sure they weren't talking about attaching it to the layer below? Hold the Alt key between the two layers and the cursor will change.

Thanks, but I am very comforatable with my understanding of
adjustment layers.

I thought I had seen someone talk about a blank layer that could
then be used to make other adjustments on. I could easily see
painting etc... on this new blank layer, but I thought the post
said something about being able to sample information from the
layers below it, say for the clone stamp, healing brush etc...

--
Mighty EEE OH's Twenty Dee
Pbase Supporter
Proud FCAS Member! #56 (with CP5700)
http://www.pbase.com/billneve

 

[Phill Brannon]

Thanks, but I am very comforatable with my understanding of
adjustment layers.

I thought I had seen someone talk about a blank layer that could
then be used to make other adjustments on. I could easily see
painting etc... on this new blank layer, but I thought the post
said something about being able to sample information from the
layers below it, say for the clone stamp, healing brush etc...

You can use many of the tools on a blank layer if you check "Sample All Layers" in the options bar.

--
Mighty EEE OH's Twenty Dee
Pbase Supporter
Proud FCAS Member! #56 (with CP5700)
http://www.pbase.com/billneve

--
Phill

 

[loredana]

Say you have a portrait and you want to correct a small blemish on the skin. You needn't copy the whole background layer. Instead, make a blank layer above the background layer.

If you then select, for example, the healing brush, you will see that you have an option to "Sample all Layers". If you turn this on, you can sample from the background layer while making changes on the new, blank layer.

This allows you to have a very small second layer, since only the (corrected) blemish will be present there. (try hiding the background layer and you'll see what I mean.)

Sorry if this is overly simplistic, I think this is what you're asking.

--
Lori

 

[Isola Verde]

Shame really that JPGs can't contain transparent areas (they can't can they?).

For instance, a 3.2MB JPG, without any changes, becomes 22.7Mb when saved as a lPSD file. Partial layers, containing adjustments, copied and clone stamped bits etc increase this - with a complete duplicate layer doubling the file size, to a sizeable 55Mb.

If you could save the additional layers as separate JPGs, and easily recombine them in PS again, what a lot less space they'd need!

Presumably, the original JPG and - say - four 50% layers as individual JPGs would only need a total of 9Mb.

Or is there a trick I've missed?

--
Peter
http://www.pbase.com/isolaverde

 

[cspringer]

hmmm....mine stay the same.

For instance, a 3.2MB JPG, without any changes, becomes 22.7Mb when
saved as a lPSD file.

 

[Isola Verde]

For instance, a 3.2MB JPG, without any changes, becomes 22.7Mb
when saved as a lPSD file.

I've got a HD littered with PSD files around 20Mb - I'd love to know a way to get them down to 3MB without reducing the number of pixels.

--
Peter
http://www.pbase.com/isolaverde

 

[Mr Steve]

I've got a HD littered with PSD files around 20Mb - I'd love to
know a way to get them down to 3MB without reducing the number of
pixels.

I'm not an expert, but I don't it's possible.

You can reduce the size, and not lose any pixels, by saving the file as an 8-bit compressed TIF file.

Examples:
9 mb RAW (NEF) file --> 12.7 mb TIF (LZW)
2.7mb jpg --> 23.8 mb PSD = 8.7 mb TIF (LZW) = 7.9mb TIF (ZIP)

Mr. Steve

 

[Isola Verde]

For instance, a 3.2MB JPG, without any changes, becomes 22.7Mb when
saved as a lPSD file.

Still trying to figure out if you're adding to the sum of human knowledge or just being pedantic?

Of course the size of a JPG file doesn't change if its contents are copied to a new file that's then saved in the PSD format.

Was that your point?

--
Peter
http://www.pbase.com/isolaverde

 

[Mr Steve]

For instance, a 3.2MB JPG, without any changes, becomes 22.7Mb when
saved as a lPSD file.

Still trying to figure out if you're adding to the sum of human
knowledge or just being pedantic?

Of course the size of a JPG file doesn't change if its contents are
copied to a new file that's then saved in the PSD format.

Was that your point?

--
Peter

He didn't have a point. But I hope my message helped a bit.

 

[Isola Verde]

Sorry, this tree view makes keeping replies in order a bit difficult!

Don't know much about TIFF Zips - but will go and find out now.

Still looking for a good way to organise file - I'd hoped 160Gb fixed HDD plus 80 and 40 externals would be enough but it's surprising how much space you need!

--
Peter
http://www.pbase.com/isolaverde

 

[JJMacks]

When dealing with Digital Images there are many size requirement that must be meet. An image will have many states of existences when it in being process , manipulated and viewed. Each state requires storage or some sort Ram, swap, page disk. When not being process or view they are stored in image file on some external media. There are many image file formats some standard and some propriety. Many file formats use compression other do not. Image files cont aim more then just the image. Besides the image data you have meta data (exif, iptc, private camera data, thumbnails etc). Some formats supports layers. Therefore a Digital Image saved to external media in an image file format have different sizes depending on which file format you store it in and what the file format supports.

Understanding storage may help you process images faster. You can accomplish, achieve the same image in Photoshop many ways knowing which way require fewer system resources will help a lot. The fewer bytes Photoshop has to manipulate the faster it will perform. Image data can quickly become huge. When it does your system will start straining things will bog down there will be a lot of system page and Photoshop swapping.

I'm not going to try to enumerate Photoshop's storage requirement. Just think a bit about the basics. A Jpeg image file-size may be quite small very small if encoded with high compression low image quality, But once decoded its back to its original 8bit image size. If a 3MB Jpeg file was produced by a 8Mpixel Camera in memory the are three Arrays(maps, Channels what ever) one for each color. Each element has a 8bit size or one byte. So the background Layer that has no Layer mask is 3(8M) or 24MB in memory. If you dupe that layer the second layer is also 24MB in memory if you do a luminosity selection ctrl+alt+~ and click on the add layer mask icon to add a layer mask to the duped layer so you can work on the shadows or highlights it like adding an additional channel so that later is now 32MB. Each layer also has a few bytes extra for its setting opacity, fill and styles(blending effects etc). All layers do not have the sane size requirements. Layers need not all cover the same area. It is possible to have layers that are much larger and smaller then the canvas size. Some layers may have no image data at all just some settings for its adjustment.

Saving a image in layered PSD format can help you get a better understanding of the number of bytes Photoshop is manipulating. Photoshop requires more memory than PSD File-size to work on the image. It requires a work area at least 3 time canvas size to create a composite of all layers, a buffer 3 time window size so it can render the image you see while you working on the image. Photoshop is also a large program which requires memory and often has a companion known as the bridge tagging along. Adding lots of fonts, plug-ins, action also will require more system resources. Think about system resources you may want to make some adjustments to your Photoshop environment and how you process images.
--
JJMack

 

[Mr Steve]

If you're using Photoshop, you save the file as a TIFF file.
Then a dialog box appears, giving you choices for saving the TIFF file.
Save the TIFF file using LZW compression or ZIP compression.

The latter is not a zip file, it's still a TIFF file but uses ZIP compression algorithm.

-mr steve

 

[cspringer]

I'm assuming that is because they have been edited. I open a JPG and convert to PSD and the file size is the same. Once I start editing it gets much bigger.

For instance, a 3.2MB JPG, without any changes, becomes 22.7Mb
when saved as a lPSD file.

I've got a HD littered with PSD files around 20Mb - I'd love to
know a way to get them down to 3MB without reducing the number of
pixels.

--
Peter
http://www.pbase.com/isolaverde

 

[JJMacks]

I'm assuming that is because they have been edited. I open a JPG
and convert to PSD and the file size is the same. Once I start
editing it gets much bigger.

Photoshop does not support compression in PSD files so a PSD file should always be larger then a corresponding jpeg file no matter what image quality is used during jpeg encoding. How did you convert to PSD. I created a directory call Duck. Copied a 229KB Duck.jpg File into it. I double click on its icon and it opened in Photoshop. Then did a "Save As" and selected file type PSD and clicked save. The Duck.PSD file size is 1,424KB I did a "Save as" again an selected jpeg as the file type and selected image quality 12 and named it Duckquality12.jpg and clicked save its size is 351KB.



--
JJMack

 

[Mr Steve]

I'm assuming that is because they have been edited. I open a JPG
and convert to PSD and the file size is the same. Once I start
editing it gets much bigger.

Did you save the PSD file that's the same size as the JPG?

 

[bkuhl]

Thank you VERY Much! I was just not looking in the right place for the "sample all layers" option.

I have learned SO Much from the great people in these great forums. I try my best to pay back whenever I can.

Thanks Again (Everyone).

Bill
--
Mighty EEE OH's Twenty Dee
Pbase Supporter
Proud FCAS Member! #56 (with CP5700)
http://www.pbase.com/billneve