resizing of RAW files

[claudia26]

I usually work with PSD files and need to resize and convert them to jpeg for the slideshows ; is there a rule of thumb for the conversion , such as reducing them to 50% quality ? Or can I just use the full size jpegs ( around 5MB each) - I have not found the "formula' yet .

[Barry Beckham]

Claudia

You need to avoid using 5mb files in a slide show. We don't need high resolution for slide show images, but we do need to retain quality. If your making your slide shows to fit your monitor for example, lets assume that monitor runs at a 16:10 format using a resolution of 1920*1200 pixels. You make your images all that size and this is how you do that.

Open the PSD images into Photoshop or Elements and select the crop tool. In the options at the top of the screen enter the resolution you want. In this example 1920px for the width and 1200px for the height. (don't forget the PX)

Click and drag the crop shape to determine what part of the image you want to show, hit the enter key or the tick to complete that.

You may want to add a little extra sharpness in your images after cropping.

Now save your image as a Jpeg file and use level 6. Level 6 is the default setting and is a great balance between size and quality. You will hear lots of nonsense talked about this compression setting with people suggesting you will lose quality. Ignore them and judge for yourself. You will find it is just right abd I have been doing that for years.

Why can we get away with images in our slide show that would be considered low resolution for any print we would want to make? Because slide show images will not be enlarged and we view them in a similer way as we do web images, as they are presented. In addition they are only on screen for a few seconds.

If and when you want to add animation to an image, lets say add a delicate pan, then you can create a larger image for the one image you want to pan. Try 2300px for the width and 1200px for the height. We don't need to add extra height if our intention is to pan. If we wish to zoom, then we will need extra pixels on the width and the height.

I did write something about this on my web site, that might be of help

http://www.beckhamdigital.co.uk/audiovisual/images/image%20%20size.htm

[claudia26]

Thank you very much for your detailed reply ; this helps a lot . I use lightroom to export and convert the files . That way I can treat all pictures at once .

[Barry Beckham]

I am not a user of Lightroom myself, but I assume it will do much of this for you, but don't disregard manual sizing of images. It does allow you to take strategic parts of images and that can be an advantage sometimes

[AnKo]

Hi Claudia (and Barry),

I use Lightroom too and I crop my RAW/NEF images when needed. But that is part of my workflow in Lightroom before export/resizing them for use with PtE. So when I want to make a slideshow I use these already developed images (you can FLAG or TAGG them to make selecting them even more simple).

For resizing these ready RAW/NEF images I use the next rules,asuming you have a 1920x1200 monitor:

1: select those images which are taken with the camera in normal position (the long size is the top of the image)

2: go to EXPORT

3: select the folder to export to

3: make the LONGSIDE 1920 px and let Lightroom determine the size for the short side (keep aspect ratio)

4: select the RGB colourspace

5: export

For images taken with the camera 90 degrees turned (the shortside is the top of the image) you only have to change rule 3 and make the shortside 1920 px. I always use the max jpg quality, just to be sure, and to avoid any discussion about this subject.

This way you don't have to crop any image again (just resize) and they will all fit the longside HD output format (1920px) in PtE. Now the "cropping" can be done in PtE itself in the Q&A window by moving the image a bit up or down.

This saves a lot of time cropping each image the way you want them and I do not see any disadvantage in it.

Kind regards,

André

[Peter S]

In Photoshop under the File Menu there is an option Save for Web ... Elements, b]Save for Web and Devices CS4. This allows you to use the same settings that Barry recommends and to see side by side comparisons at different quality settings. This should convince you that 6 is OK. If you are working in a colour space other than sRGB you can (and should) make the conversion here as well. As Barry says it's best to make your selective crop first although you can resize in the Save for Web panel. The panel is rather better in CS4 than it is in Elements but they effectively do the same thing. See the Help button in the panel for more information.

If you use this approach you will get smaller files because all the extraneous file information is stripped out to make the file as small as possible which suits our slide shows nicely.

I would be interested to know why this method is not more widely recommended. A quick trial should convince anyone that it does give smaller file sizes.

Kind Regards

Peter

[Ronniebootwest]

Peter,

I have not really given much thought to which colour space to use, I tend to stick with RGB because I am lazy. You have now promted me to think about the other options. What are the advantages of using sRGB against RGB - or even CYMK?

Ron

[fh1805]

Peter,

What you say is true but it must be borne in mind that the smaller file size has relevance only in terms of disk or other external storage space. A JPEG image file of 1280x1024 pixels will always occupy exactly the same amount of main RAM or graphics RAM after decompression, irrespective of how small the file size might have been. Each of those pixels, when decompressed, needs the same number of bits (16 I think) to encode its attributes. And so each image will require 2.4MB of RAM whether compressed to level 1, level 6 or level 12 (or to 20%, 40% or 80% if saving to web).

regards,

Peter

[Guest Yachtsman1]

Peter,

I have not really given much thought to which colour space to use, I tend to stick with RGB because I am lazy. You have now promted me to think about the other options. What are the advantages of using sRGB against RGB - or even CYMK?

Ron

Hi Ron

RGB is usually used for printing, sRGB is for projected or web images.

Regards Eric

Yachtsman1

[fh1805]

Ron,

...and CYMK is used by commercial print shops.

regards,

Peter

[claudia26]

Thanks to everyone for the helpful comments ; I am in the middle of putting together a number of short PTE slideshows , set to individual tracks of music . Does any of you have a suggestion as to how to string them together to be run as a continuous set ?

[Lin Evans]

You won't be able to copy and paste the music so that will have to be entered manually after stringing the slideshows together. To do that, open the slideshow you want to copy. Go to main menu and select all slides. Do not "close" this slideshow but rather just do a "file" "open" and open the slideshow which you want to add to. Paste the copied slides in the main slide list and all slides, animations, etc., will be there when you save this show. Next add the music tracks and save again.

Repeat by opening the second slideshow you want to copy from....

Lin

Thanks to everyone for the helpful comments ; I am in the middle of putting together a number of short PTE slideshows , set to individual tracks of music . Does any of you have a suggestion as to how to string them together to be run as a continuous set ?

[fh1805]

Claudia,

You could chain them in a fixed order by using the Project Options...More tab to set "Run application/slideshow on exit".

regards,

Peter

[claudia26]

You won't be able to copy and paste the music so that will have to be entered manually after stringing the slideshows together. To do that, open the slideshow you want to copy. Go to main menu and select all slides. Do not "close" this slideshow but rather just do a "file" "open" and open the slideshow which you want to add to. Paste the copied slides in the main slide list and all slides, animations, etc., will be there when you save this show. Next add the music tracks and save again.

Repeat by opening the second slideshow you want to copy from....

Lin

Thanks Lin ,

But then the pauses between the tracks will be dictated by the tracks themselves and cannot be modified I guess .

[fh1805]

Claudia,

Do you want to run them as a "continuous" set - or do you want to be able to trigger each one manually after a brief "live" introduction? Your requirements are not clear to me and so I am in danger of giving you completely the wrong advice.

regards,

Peter

[Peter S]

Peter,

I have not really given much thought to which colour space to use, I tend to stick with RGB because I am lazy. You have now promted me to think about the other options. What are the advantages of using sRGB against RGB - or even CYMK?

Ron

Ron,

This is getting into deep territory. As I understand it in simple terms the sRGB colour space "sees and records" a smaller range of colours than your eye. The Adobe colour space sees more than sRGB and Pro Photo sees even more. Lightroom and Adobe Camera RAW work in ProPhoto 16 bit. If you are shooting in RAW the colour space profile only gets applied after you save the file as a PSD or TIFF etc. So the camera setting of sRGB or Adobe RGB has no effect on RAW images. If you want to get the best tonal transitions in your images it pays to work in the largest colour space you can when you are doing any editing involving tonal changes. When it comes to presenting your images on screen they need to be in sRGB so they need converting. I once inadvertently loaded a ProPhoto image onto a web site it was awful!

Martin Evening actually says in his Adobe Photoshop CS4 for Photographers that sRGB is an ideal color space for web design but is unsuitable for photography or serious print work! I know that many people will totally reject this and I have seen some great prints made by people who only ever use sRGB all through their processing. Could they have had smoother tonal transitions? Who knows? The theory says they could!

Kind regards

Peter

[Peter S]

Peter,

What you say is true but it must be borne in mind that the smaller file size has relevance only in terms of disk or other external storage space. A JPEG image file of 1280x1024 pixels will always occupy exactly the same amount of main RAM or graphics RAM after decompression, irrespective of how small the file size might have been. Each of those pixels, when decompressed, needs the same number of bits (16 I think) to encode its attributes. And so each image will require 2.4MB of RAM whether compressed to level 1, level 6 or level 12 (or to 20%, 40% or 80% if saving to web).

regards,

Peter

Well Peter,

I never knew that! I had imagined that the larger file size would mean more work for the computer to render the images.

I guess storage space is pretty cheap these days so it's no big issue but every little helps.

Kind regards

Peter

[claudia26]

Claudia,

Do you want to run them as a "continuous" set - or do you want to be able to trigger each one manually after a brief "live" introduction? Your requirements are not clear to me and so I am in danger of giving you completely the wrong advice.

regards,

Peter

Peter ,

I want to run them as a continuous set but I need to be able to control the space between the shows ; the music tracks have odd seconds of silence and I'd like to clean that up when stringing the shows together .

[fh1805]

Claudia,

In that case you will need to edit your music tracks in a sound editor program such as Audacity (http://audacity.sourceforge.net)

regards,

Peter

[claudia26]

Claudia,

In that case you will need to edit your music tracks in a sound editor program such as Audacity (http://audacity.sourceforge.net)

regards,

Peter

Thanks once again , I am looking into it .

[cjdnzl]

Ron,

This is getting into deep territory. As I understand it in simple terms the sRGB colour space "sees and records" a smaller range of colours than your eye. The Adobe colour space sees more than sRGB and Pro Photo sees even more. Lightroom and Adobe Camera RAW work in ProPhoto 16 bit. If you are shooting in RAW the colour space profile only gets applied after you save the file as a PSD or TIFF etc. So the camera setting of sRGB or Adobe RGB has no effect on RAW images. If you want to get the best tonal transitions in your images it pays to work in the largest colour space you can when you are doing any editing involving tonal changes. When it comes to presenting your images on screen they need to be in sRGB so they need converting. I once inadvertently loaded a ProPhoto image onto a web site it was awful!

Martin Evening actually says in his Adobe Photoshop CS4 for Photographers that sRGB is an ideal color space for web design but is unsuitable for photography or serious print work! I know that many people will totally reject this and I have seen some great prints made by people who only ever use sRGB all through their processing. Could they have had smoother tonal transitions? Who knows? The theory says they could!

Kind regards

Peter

Hello Peter,

I have for come time been attempting to get my head around this color space theory, but one thing that really surprised me -though it shouldn't have - is that regardless of the color space, all use the same number of bytes to specify individual colors, e.g. a so-called '16-bit' image uses 6 bytes for every pixel (16 bits or two bytes for each primary color). Whether those bytes are used for an sRGB color space with a narrow gamut, or aRGB or ProPhoto with wider gamuts, the color space is still represented by the same number of bytes. How can this be? because, simply put, the steps between shades of colors are bigger with the wider gamuts, so to use a wide gamut, you sacrifice the smoothness of the image. In 16-bit images it probably doesn't matter, but with 8-bit images you can see the difference. You might gain more colors in the far green and red, but you are using bigger steps to get there. If the subject matter is such that there are no extreme colors involved, then there is no point in using wide gamuts. sRGB is the standard color space that monitors and projectors, and also many printers can handle. aRGB and Prophoto are specialized gamuts that in practice do not help the ordinary photographer with day-to-day images, nor do they render well on sRGB-oriented equipment. For these reasons I stick to sRGB.

Best regards,

Colin

[Barry Beckham]

Forgive me for saying this and it is a general statement, but why get bogged down with things like colour space. I say this with all due respect, but there are a 101 other areas that need our collective attention in AV before we get bogged down with this.

Colour space has never been the tiniest thought in my head while making a slide show, has it prevented me from doing that. Not a jot

Here are two of those 101 that are missed over and over again.

Image quality and matching images to music and niether of those will be helped with all the theory in the world about colour space.

[claudia26]

Latest update : to string the slideshows with individual tracks of music together , Adobe Encore works fine ; we just did a trial DVD assembly .

[cjdnzl]

Forgive me for saying this and it is a general statement, but why get bogged down with things like colour space. I say this with all due respect, but there are a 101 other areas that need our collective attention in AV before we get bogged down with this.

Colour space has never been the tiniest thought in my head while making a slide show, has it prevented me from doing that. Not a jot

Here are two of those 101 that are missed over and over again.

Image quality and matching images to music and niether of those will be helped with all the theory in the world about colour space.

Color space is very relevant to slide shows, as has been attested to by posters in these forums. Shows made with aRGB (a=adobe)look flat and lifeless when projected on sRGB equipment. Show makers do need a working knowledge of various color spaces if they want to optimize the show quality. But, it's really very simple. For slide shows, use sRGB.

Regards,

Colin

[Barry Beckham]

Colin

All my images are in Adobe RGB, so thats where I must be going wrong