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Posted

I have heard Barry Beckham state that he can exit to Photoshop from within PTE, do what he has to and then come back to PTE. Unfortunately he doesn't say how this is done. Can anyone help? I imagine that there must be a function key stroke for this.

Many thanks

Alastair Knox

Posted

Control Panel - Folder Options - File Types.

See what JPEG is associated with - if you want it to be CS2/CS3 click on CHANGE and alter it.

However, double clicking on a JPEG from within PTE does not have that effect.

Right click on a JPEG in the slide list and click on EXPLORER - you have the option to "Edit With Photoshop".

Personally, I would never advise this because opening a JPEG in PS, editing it and re-saving involves a further step of compression and hence loss of quality.

You SHOULD be going back to the last saved TIFF or RAW file.

DaveG

Posted

You can break out to any application by selecting a slide in the Slide List and then doing: Customize Slide...Main...Run external application - and browse to the program that you want to launch. Instead of an application program, you can select a file (e.g. myfile.doc) and then the associated application will be launched and that file opened (e.g. Microsoft Word for myfile.doc)

Posted

from the slide list

r mouse on the selected pict

open picture

and in my case Irfanview is the default graphic editor for jpgs and the picture opens

access the pct from the light table - same commands to open it

also from the slide list if my memory serves me right

r mouse select rename and the root pict is renamed as well as the selected pict

in earlier versions just the pict in slide list was renamed

ken

Posted

DaveG

Personally, I would never advise this because opening a JPEG in PS, editing it and re-saving involves a further step of compression and hence loss of quality. You SHOULD be going back to the last saved TIFF or RAW file.

That statement is a little OTT Dave, if you don't mind me saying. Your taking some important information and applying it a little too rigidly. Have you EVER seen any evidence of a loss in quality while making a slight change in Photoshop in this way, because I never have and I have done it 1000's of times.

The sort of changes you are likely to make once your images are already in PTE are going to be minimal, adding a white, black line, sharpening, selectively softening to defeat moire etc etc.

You are likely to lose loads more quality by animating the image, because in most cases you then cannot sharpen it.

Don't worry about opening images directly from PTE via Ctrl+W and then taking them back into PTE. I do it all the time with no problem whatsoever. Take a look at these two images. Both have been reduced to 1024*768, no sharpening added. Then one of these two was opened and saved using Jpg level 6 - 10 times. Each time fully closed and opened from scratch.

Which one has been damaged by repeated saving as a Jpeg?

Posted

Further to Barry's comments above...

My training and experience as a computer programmer taught me that, if you give a computer program datastream "A" it will always produce datastream "B" unless there is an element of randomization encoded within the program. If it doesn't there is a serious bug in the code!

So, whatever the piece of code is that "unpacks" JPEG into memory will always unpack the same image the same way and, in theory, you will have in memory exactly the same data that you would have had if you had opened an uncompressed version of the same image (e.g a TIFF file).

You then make a small alteration to part of it and save it back as a JPEG. What's going to happen? Those parts of your image that haven't changed will get processed back to JPEG just as they were before you opened the file. Those parts that have been changed will be processed back to JPEG for the first time - but that is going to give you the quality that you would expect from any other first time save.

I do not believe that repeated saving to JPEG causes deterioration of the image quality to any degree that we, as AV workers, can readily see in our finished product - provided that we do not alter the settings for the JPEG file (i.e. if you're using level 8 then stay at level 8 every time).

If you start changing the JPEG quality values then for sure you are going to see a quality difference. And once you've dropped the quality level down there is no way you can get the quality back without stepping back to an earlier, higher quality version of that file.

That's how I see it. I'm willing to be persuaded that I'm wrong.

Posted

I stick by what I said but in deference to both of you I will amend:

"REPEATEDLY opening a JPEG in PS, editing it and re-saving involves a further step of compression EACH TIME and hence loss of quality HOWEVER SMALL.

You SHOULD be going back to the last saved TIFF or RAW file IF YOU WANT TO MAINTAIN THE HIGHEST QUALITY.

DaveG

Posted
Further to Barry's comments above...

My training and experience as a computer programmer taught me that, if you give a computer program datastream "A" it will always produce datastream "B" unless there is an element of randomization encoded within the program. If it doesn't there is a serious bug in the code!

So, whatever the piece of code is that "unpacks" JPEG into memory will always unpack the same image the same way and, in theory, you will have in memory exactly the same data that you would have had if you had opened an uncompressed version of the same image (e.g a TIFF file).

You then make a small alteration to part of it and save it back as a JPEG. What's going to happen? Those parts of your image that haven't changed will get processed back to JPEG just as they were before you opened the file. Those parts that have been changed will be processed back to JPEG for the first time - but that is going to give you the quality that you would expect from any other first time save.

I do not believe that repeated saving to JPEG causes deterioration of the image quality to any degree that we, as AV workers, can readily see in our finished product - provided that we do not alter the settings for the JPEG file (i.e. if you're using level 8 then stay at level 8 every time).

If you start changing the JPEG quality values then for sure you are going to see a quality difference. And once you've dropped the quality level down there is no way you can get the quality back without stepping back to an earlier, higher quality version of that file.

That's how I see it. I'm willing to be persuaded that I'm wrong.

Hello Peter,

As I see it, the flaw in your argument is the fact that the jpeg algorithm throws away parts of the image when saving it to a file, which is why it is called a lossy compression. When you open the file again, the image presented is not the same as the one you saved earlier; it is missing the thrown-away data, and contains artifacts that were not present in the original image. The differences may not be obvious, but they are there. It may well look identical on a 72 ppi monitor, but it isn't identical at all.

Also, once an image has been saved as a jpeg at a certain size, just simply opening and saving it again without doing any modifications will cause the file size to be different. I just did this with a jpeg from a 5D image, first save was 8,158,695 bytes, reload and second save was 8,229,894 bytes, almost a 1% increase in size - and that was at Photoshop level 12, the maximum quality setting. The increase in size comes from the artifacts that were there from the earlier save; and they and the file size will increase with each subsequent save.

If your quality criterion is purely visual, on a monitor or a projector, then the deterioration in quality may not matter, but there is no question that repeated saves of a jpeg image will incrementally but surely reduce the image quality.

Regards,

Colin

PS: The same thing happens with mp3 audio as well. Listening to a 2nd or 3rd generation mp3 saved from an audio editor will show an audible difference. Don't confuse copying a sound or image file with opening and saving a file in an appropriate editor. Simply copying does not introduce deterioration, it's opening and saving that does.

Posted
DaveG

Personally, I would never advise this because opening a JPEG in PS, editing it and re-saving involves a further step of compression and hence loss of quality. You SHOULD be going back to the last saved TIFF or RAW file.

That statement is a little OTT Dave, if you don't mind me saying. Your taking some important information and applying it a little too rigidly. Have you EVER seen any evidence of a loss in quality while making a slight change in Photoshop in this way, because I never have and I have done it 1000's of times.

The sort of changes you are likely to make once your images are already in PTE are going to be minimal, adding a white, black line, sharpening, selectively softening to defeat moire etc etc.

You are likely to lose loads more quality by animating the image, because in most cases you then cannot sharpen it.

Don't worry about opening images directly from PTE via Ctrl+W and then taking them back into PTE. I do it all the time with no problem whatsoever. Take a look at these two images. Both have been reduced to 1024*768, no sharpening added. Then one of these two was opened and saved using Jpg level 6 - 10 times. Each time fully closed and opened from scratch.

Which one has been damaged by repeated saving as a Jpeg?

The second one. This is apparent if you look at the image closely, despite the limitations of a small image and monitor, and is most obvious in the lion's lower teeth.

It is also proved by looking at the image properties. The second image is bigger than the first, 175,683 bytes vs 174,361, which is characteristic of resaved jpeg images.

Practically, there is no obvious drawback to using the second image for slide shows, specially if the first image is not available for comparison, so the situation is more theoretical than practical, fortunately.

Colin.

Posted

Hi Colin,

I too, have made the same point regarding MP3s on previous occasions.

For most practical purposes you probably won't tell the difference between save 1 and save 2 but try comparing save1 with save 5 or 6?

My remarks were intended to indicate GOOD PRACTICE - nothing more.

DaveG

Posted

Colin,

Thanks for your response to my previous post. I've just carried out a little test. I used an image that had, up to this point, only been uploaded from my Nikon D70. the process flow was as follows:

- Launch Adobe Photoshop Elements v5

- File...Open...Image1.jpg

- File...Save As...Image2.jpg (taking all my normal values for any settings along the way)

- File...Open...Image2.jpg

- File...Save As...Image3.jpg (taking all my normal values for any settings along the way)

- File...Open...Image3.jpg

- File...Save As...Image4.jpg (taking all my normal values for any settings along the way)

- File...Open...Image4.jpg

- File...Save As...Image5.jpg (taking all my normal values for any settings along the way)

As expected, the first iteration produced a much smaller file (because of the parameter values associated with this save). Thereafter I witnessed a small reduction in file size at each subsequent iteration. Note it was a reduction and not an increase - of the order 100 bytes or less in a file size of just under half a million bytes.

From this brief test I conclude that the implementation of the JPEG algorithm in Adobe Photosho Elements 5 is actually fundamentally flawed. I say this because, to any person of average intelligence, the act of opening a file into a piece of software and then saving it to a new file name without making any changes to the content should result in a perfect copy of the file. Clearly this is not the case with this JPEG algorithm.

However, from the perspective of an audience watching an audio-visual sequence, the differences that do come about are undetectable to the human eye on a single viewing with nothing to compare against.

I repeated the same test, saving the image as a TIFF file. The first Save As...tif gave me a file size of 18,073,864. This file was then Opened in Photoshop Elements 5 and then Saved As...tif to a new file name. If the argument put forward by Colin is correct then this second file should be exactly the same size as its predecessor. It wasn't; it was 18,073,908 - a very tiny growth in size. The next iteration produced a file size of 18,073,908 - this one was the same size! From this I conclude that even saving as a TIFF file doesn't guarantee to produce an identical file. The file content can change across a save with no actual modification made anywhere between open and save.

Although there is a real and quantifiable problem I believe that it is not a serious issue for an A-V worker. As with so many other aspects of our work, we can often see things that we would wish to improve because we see the sequence over and over again during its creation. An audience typically sees it once and once only and rarely spots any of the weaknesses that loom so large in our minds.

Posted
.... From this I conclude that even saving as a TIFF file doesn't guarantee to produce an identical file. The file content can change across a save with no actual modification made anywhere between open and save....

Hello Peter,

You can use a tool like Total Commander (http://www.ghisler.com/) in order to compare the contents of your files (file menu > compare by content). I think that the tryout version of TC never expires, but it will show a nag screen at startup. Once purchased, all updates are free.

Best regards,

Xaver

Munich

Posted

Using Photoshop CS2, six consecutive "save as" operations: JPG at quality 12, file size increased 5K in a 3MB file; JPG at quality 6, file size decreased 1.2K in a 340K file; BMP files stayed the same size; TIF files (uncompressed) increased in size 36 bytes for a 7MB file.

The TIF file change *might* be from changing the non-picture information in the file. Just a thought.

I could see little or no difference on my monitor between first and sixth JPG files. In fact, the differences between quality 12 and quality 6 were not significant either (bearing out Barry's advice that anything higher than quality 6 is wasted in a PTE show). So, my free advice is for anyone in doubt to run a similar test to set your mind at ease.

But, if you want the best file quality in JPG, then use a lossless editor like Lightroom. The JPG is never changed, no matter what editing you do, so you can always go back and undo some or all of your edits and keep the original's quality intact. When you're happy with the photo, you export a copy for use in PTE. You're never further away in quality from the original than that one copy operation.

Posted

Hi Argonaut,

Might I (VERY RESPECTFULLY) suggest that your methodology is flawed because you haven't actually edited the files before successively re-saving?

The whole point about the discussion is that it has been suggested that a JPEG be opened from within PTE to carry out an edit step.

The two attached files are the original and sixth save in a procedure which actually involved edit steps. Both are actual pixels crops from the 1024x768 originals.

When these are placed on layers in PS and the sixth toggled on and off there is a discernable difference between the two.

DaveG

post-2488-1214907550_thumb.jpg

post-2488-1214907560_thumb.jpg

Posted
.... But, if you want the best file quality in JPG, then use a lossless editor like Lightroom. The JPG is never changed, no matter what editing you do, so you can always go back and undo some or all of your edits and keep the original's quality intact. When you're happy with the photo, you export a copy for use in PTE. You're never further away in quality from the original than that one copy operation.

Hi Argonaut,

Your method (keeping raw images plus metadata) may work under the condition that Lightroom or ACR, version 4 (with similar functionality) provides all what you need for image precessing. But this method will fail if you like to apply particular filters (e.g. Nik), make enhancements using the Lab space, use selctions, transformations, masks, layers, particular blending modes (whatever a powerful image editor will offer).

Best regards,

Xaver

Munich

Posted

Hi Argonaut,

Did you mean "The RAW is never changed, no matter what editing you do" because that is exactly what I argued right at the beginning of the discussion.

Lightroom, ACR, NX2 are only "lossless" when working in RAW and even then there are limitations on what you can do.

DaveG

Posted

Davegee, to answer your point about not editing the JPG invalidating my ‘results’, good point. I was only trying to see if the actual saving process degraded the photo, and it didn’t (to my eye). The next question would be, *which* edits, if any, cause trouble? What did you do in your example? I’ll try to think of a protocol to do some testing.

Xaver, you are correct that editing in Photoshop will change the ‘master’ photo. There are things one cannot do in Lightroom but I find that 90% plus of my photos don’t need more than LR can provide. I edit a TIFF copy of my master shot if I have to go to Photoshop. (I have to point out that your statement, “…keeping raw images plus metadata…” is not how LR works - see my next paragraph.)

Davegee, LR is lossless for all formats, not just RAW. In essence, you can work with a JPG just as if it were a RAW image (without the dynamic range, of course). All edits are separate from the original photo; when you view an edited photo you are seeing the original overlaid with editing instructions, not changes to the original. Everything can be undone with no harm to the original. You can export a copy of the original with or without editing changes. It’s the reason I bought LR, saddled as I am with a couple of cameras that don’t shoot RAW.

Posted

Hi Argonaut,

I think that we possibly have a terminological problem here.

I agree that LR is NON-DESTRUCTIVE DURING the editing process (as is PS), but at some stage you have to SAVE your image at which point we have to consider what is NON-DESTRUCTIVE or LOSSLESS. (Once the file is saved the edits become DESTRUCTIVE).

My criteria would be that in a LOSSLESS SAVE no compression is applied AND the original file is recoverable when the saved file is re-opened.

RAW files satisfy both criteria.

PSD files satisfy both criteria (albeit that you can't recover a RAW file from a PSD).

TIFFs satisfy just the one criteria - no compression is applied - but you cannot recover the original file before editing took place.

JPEGs satisfy neither criteria.

So, in the spirit of the the original post here LR is no different to any other editing package.

Opening a JPEG in ANY package, editing it and re-saving it is a LOSSY/DESTRUCTIVE process.

DaveG

Posted
... you have to SAVE your image at which point we have to consider what is NON-DESTRUCTIVE or LOSSLESS.

Hi DaveG,

In my understanding, a tool works non-destructive, if it opens a particular object (image, sound, ..), allows changes, saves the changes as meta-data, but does not overwrite the original input. You can open this combined object (data and meta-data) as often as you like in order to make new changes or go back to an earlier version. At each stage you can export new versions of your data, typically not overwriting the original. If the export format is lossy, you will have some loss, but you have it only once, independent from the number of export actions. I think, this is the way how Audacity works. You may start with an mp3-file (having some loss), and in several sessions you make 30 changes to your Audacity project, each of which can be exported. If your export format is mp3 again, the final version has some additional loss, but independent from the number of changes, sessions, save and export operations in between.

Best regards,

Xaver

Munich

Posted
My criteria would be that in a LOSSLESS SAVE no compression is applied AND the original file is recoverable when the saved file is re-opened.

In LR the original is used only to make "preview" copies at different sizes, depending on the way you're editing. After those previews are created, the original is not touched except to update the EXIF and IPTC data, and even that can be assigned to a separate 'sidecar' file if you wish. All edits are overlaid on whichever preview file you are using. Therefore, when you 'open' the file, you're actually opening a copy, and when you 'save' a file, you're only saving the editing instructions. This all works seamlessly so it's just like working on the original - you can't tell. When you need to print or generate a file for PTE, LR exports a copy of the original with the edits incorporated into it, but the original remains unedited, unopened, unsaved, uncompressed, etc etc..

Posted

Xaver,

Your understanding of Audacity's behaviour with sound files is correct! The original soundfile (as an .mp3, .ogg or .wav) is imported into the Audacity project file (the .aup file) and stored in a proprietary format that is Lossless. Each subsequent change is stored in the .aup file - which can be saved at any time and re-opened in a later session. Changes can be made in this way until such time as the user decides to export the project as either a .ogg, .wav or a .mp3 file. The LAME mp3 encoder allows the user to select the quality level for the .mp3 file thus leaving control of the amount of "loss" in the user's hands to some degree.

Posted

You are all, with the greatest of respect, saying EXACTLY what I said at the very beginning (in your own ways).

You have to go back to an ORIGINAL of some description, be it RAW, PSD, TIFF, JPEG (or WAV) rather than open a previously edited and saved JPEG (or MP3) from PTE.

What the original poster wants to do is open the SAVED JPEG and edit again - Argonaut is suggesting that LR ( I don't know the programme) saves a sidecar file so that the original JPEG can remain unsaved - if that is what it does - GREAT. But that is NOT what the original poster wanted to do.

Opening a saved JPEG (MP3) and re-editing it, saving as JPEG (MP3) again involves a further step of compression which is avoided if working on the original.

DaveG

Posted

Dave,

What the original poster wanted to do was:

...exit to Photoshop from within PTE, do what he has to and then come back to PTE...

No mention of editting JPEG files! In the early responses Ken Cox and I gave him some advice on how to breakout of PTE into Photoshop (Ken) and any other software (me).

The thread has, from that point on, then wandered along a route of its own devising and has given us all an opportunity to explore various related aspects. And that is what makes this forum such a great thing to be part of. We can have some damned good discussions/arguments/disagreements - and yet, at the end of the day, all the forum users benefit to a greater or lesser extent.

For the record: I am entirely in agreement with your view that all editting is best done using a "Lossless" format. But I also can accept the pragmatic approach which says that I can, at times, get away with an edit on the 1024x768 JPEG safe in the knowledge that my viewing audience will never know or be able to spot that I've done it.

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