worn out question but need help

[Deb]

Hi all, I can't seem to get this. I know I need a small (ie. < 150kb) photo size. What is the best way to obtain this size and still have good quality from a 5MB photo that will fill the screen at 1024x768? Mine are either jagged after manipulation or not big enough to cover the area of the presentation. I have photoimpact, irfanview, and photo resizer pro to try this with. Also, should I use full size and full resolution images for a DVD presentation or will this cause problems in the video? Thanks for help. Deb

[JRR]

Deb:

I have done no DVD work, so I won't touch that aspect.

I would size them at 1024x768, I assume one of those softwares has a batch mode to that for you. (I don't use those softwares so I can't give you a definitive answer .. sorry)

You do NOT have to touch the resolution, simply leave them at the res they come from the camera and simply reduce the pixel diemnsions.

But sometimes you don't want to do a simple reduction in size, sometimes you want to crop them to eliminate some portions of an image, or crop some that will be shown in sequence so as to get certain aspects of each image to line up for the best transition. So don't always do a blind size reduction.

With the new versions of PTE I don't worry about the 150kb max size any more, I aim at about 300kb, a little higher particulalry if there are slight variants of colour in the sky, or smokey clouds reflecting night lights. Denser images, can be reduced a little smaller in terms of kbs that "thin" images.

Depending on the amount of detail in the images etc, a quality 6 or 7 (out of quality 10) will likely work for most daytime "busy" shots. Less busy shots can go with a higher quality.

[Deb]

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Thanks Jim for the information. That helps me understand. Irfanview is working well for this! Deb

[Tripstrilles]

Hello Deb,

I have test this for a long time. I have a plasma-tv and I have maken PTE-exe shows for viewing with my notebook at TV, and I have maken DVD-shows with Movie Factory 4.

1. All images I edit with my photo editing software

2. In batch-mode I convert all images ( 5 Megapix) to a resolution of 1500 x 1125

3. Nikon told me, that this will prevent - moiree - by viewing with a beamer

4. By viewing with notebook (widescreen 1280 x 768), my plasma-tv changes the resolution to 1280 x 768 too and I get the sharpest view on screen I have ever seen.

5. My images have a size of 1 MB, but with new PTE 4.42 ther is no problem with any transition. All transitions are very smooth. The compression is for best quality 97 % (low compression).

My PC is an Athlon 2000, 512 MB Ram, Notebook Centrino 1,6 Mhz, 512 MB Ram.

If you have a slowlier PC, you can compress your images to 85 % and you will not see any jaggies.

By making a DVD (PAL or NTSC) you can also use the resolution of 1500 x 1125, but not less than 1024 x 768. The quality of DVD is a little unsharper, because the images will be resize to 720 x 576 (PAL) or lower for NTSC.

I make shows on DVD with Movie Factory 4, single pass, 9800 kb/s..

I hope, this will be helpful for you and other.

Greetings from Germany, Rainer

[Ronniebootwest]

You do NOT have to touch the resolution, simply leave them at the res they come from the camera and simply reduce the pixel diemnsions.

.

This statement needs to be explained I think!

I am of the opinion that resolution should be set to 72 or 96. Am I wrong?

Ron

[JRR]

Ron

This has been discussed many times on the forum and I recognize there are two views. I knew making the statement would get a reaction but we all offer our best advice.

IMHO, reducing the resolution is an unecessary extra step for screen presentations. (Changing resolution is used to determine print size.)

Why not take an image and reduce the pixel size size without reducing the resolution, and then reduce it along with the resolution, to end up with two 1024x768 images saved at the same compression rate.

Review the difference in end result in terms of quality on screen and file size etc etc.

[Ken Cox]

see

http://www.picturestoexe.com/forums//index...t=ST&f=2&t=3413

I think one of the biggest problems that users face is not letting p2e do its thing

if you have the computing power experiment -- push your system to the limit to see what it will do

my experimenting has ended up with exe's>200 mb --i have never seen a show much larger then 50 meg's on the various dl'd sites

why do something that is not req'd -- resize etc

time is time -- there are only so many hours in a day and you have to use the available time efficiently

the experimentation uses time but in the long run you will be ahead of the game because you will not be doing unnecessary things -- you will have more time for your creativity to surface

once the exe is complete, it is done and the cpu use is minimal -- use the taskmon and see what performance tab is telling you

ken

[Tripstrilles]

@Ronniebootwest

Yes, you are wrong. What you mean is the print resolution. This is no matter for slide shows. If you have an image opened in maybe photoimpact and you look after the properties of it, photoimpact shows you a resolution (dpi) of 72 (this is only a value inside the file). If you want to print this image, you must set the print resolution at 200, or 300 or 400 dpi (dots per inch). If the image has not enough pixel resolution (5 or 6 Megapix) you may not be able to print the image in the size you want with print resolution of 300 dpi. But this is another theme.

Urgent for slideshows ist the pixel resolution. This resolution is set to 1024 x 768 or higher. It is not necessary to set it higher than 1500 pixel, see my posting above.

If you make DVD, the resolution will set with authoring software to PAL or NTSC - to 720 x 576 or smaller (NTSC). I have test it with image resolution of 720 x 576, but all images are unsharp. So it is recommended to set the smallest resolution to 1024 x 769 pixel of every image.

P.S. My slideshows are 600 MB with music, 1 MB each image, all runs well.

Greetings, Rainer

[Barry Beckham]

Are you sure you are not making this question sound far more difficlut than it really is. Just size the images to 1024*768 @ 72ppi.

If you are a Photoshop or Elements user, select the crop tool and put those sizes into the options bar. Then in one 3 second operation you can crop and size in one go.

All you will need to do after that is to sharpen the image a little.

Barry

[Ronniebootwest]

Barry said this:

Are you sure you are not making this question sound far more difficlut than it really is. Just size the images to 1024*768 @ 72ppi.

and this is exactly what I do and it works perfectly every time. The idea is to keep the size of the image as low as possible without affecting its quality. This in turn keeps the size of the finished exe to a minimum.

I agree with Barry, don't 'overcomplicate' things.

Ron

[mbskels]

Hi,

1024x768@72dpi is my current choice as well but will we all have to reconsider once pan and zoom is available?

Malcolm

[Tripstrilles]

For viewing on screen it doesn´t matter 72 dpi/ppi or 400. It does only matter for printing. For viewing the image resolution is urgent - 1024 x 768 / not more than 1500.

http://www.scantips.com/no72dpi.html

Rainer

[mbskels]

Tripstrilles

I am not an expert but I thought that the introduction of pan and zoom would require an increase in image size.

Would zooming into an image not result in pixellation if the original slide was only 1024x768?

malcolm

[Ken Cox]

Malcolm

Would zooming into an image not result in pixellation if the original slide was only 1024x768?

It does not affect it using the slideshow feature of dvdsanta - pan and zoom enabled -- it is a subtle and smooth action

ken

[mbskels]

Hi Ken,

Interesting experience.

As I said I am not an AV expert but I was surmising that zooming into an image would be achieved by gradually displaying a part of the image at full screen ie if the original image is 1024x768 then zooming in would gradually display say a 200x150 pixels section on the 1024x768 screen. This would be similar to using the zoom tool in image editing software - pixelation will result fairly quickly as zoom is applied if the original image is only 1024x768.

I suppose all will be revealed once pan and zoom is available in P2Exe. Or perhaps admin1 would be able to advise.

Malcolm

[JRR]

Malcolm

As you say we'll need to see what Igor has crafted for us with the pan and zoom, but I can tell from experience with other peoples' shows using other software with pan and zoom, that yes the image can disintegrate badly.

I am sure Igor will have good advice for us when the time comes

[Barry Beckham]

Rainer

You said that

For viewing on screen it doesn´t matter 72 dpi/ppi or 400. It does only matter for printing. For viewing the image resolution is urgent - 1024 x 768 / not more than 1500.

Your right of course, but in this context we are talking about keeping file sizes down arn't we? So, 72ppi is important if we want to avoid large file sizes.

Barry

[Ian]

Barry - you are misunderstanding the fundamental concept of image display. Your monitor or projector has absolutely no understanding of ppi, dpi or whatever you want to call it. The key issue is the actual number of pixels present in the image.

If your projector is XGA and throws out an image 1024 pixels wide, then this is the only fixed element it need to address. The number of pixels displayed "per inch" in this case will vary proportionately with the physical size of the image on the screen. If the horizontal width of this projected image is six feet, then in reality your image of 1024 pixels is actually being displayed at just 14.22 pixels per inch!

As has been stated above and many times previously, the whole concept of dpi is only applicable for images sent to the printer, and so long as you have a fixed pixel dimension the dpi setting is totally irrelevent!

There are just two settings that are important, pixel dimension and compression level. If you have a set 1024x768 dimension, then the only effect on file size is the compression setting.

If your image is bigger than 1024x786, then an XGA projector will simply "hide" the extra pixels. On large images this can lead to the jaggy edges that degrade quality, so it is generally better to save the image in a size that the projector can display easily.

Ian

[Barry Beckham]

OK, I give up..............I need a bit more experience before I can understand all this resolution nonsense.

BB

[Ian]

The 72 dpi theory will run and run!!

www.scantips.com has a lot of in-depth information about resolution, including a very thorough de-bunking of the myth of 72 dpi. Some years ago I did a precis of this for AV World magazine, and for info I've copied the article HERE.

Ian

[Ken Cox]

In addition to Ian's tutorial on 72 dpi

see

GERARD DESROCHES ENGLISH Digital Basics PAGE AT

http://gdesroches.free.fr/formation/fnumerbase_en.htm

ken

[Barry Beckham]

Ian

We are still talking at cross-purposes I think and I understand what you are saying fully. I was smiling when I said I needed a bit more experience before I can understand all this resolution nonsense. In the context of a slide show I am thinking file size and how the person making the show sees the image.

If we open an image 13ins by 9 ins approx @ 300 ppi and size the pixels only to 1024 by whatever. The image is now the correct resolution for PTE but is 3.4 in by 2.3 in on a PS screen.

In PTE the image will display fine, I know that and you know that, but newer users will get confused. Trust me they will and it has nothing to do with intelligence or lack of it.

Why, because in Photoshop or Elements the picture is too small. As we work on it, we can’t hit Ctrl+0 to open it up to the full 14.22 inches and see what we are going to get unless we set that 72ppi. We should advise newer converts to select 72 dpi and they will then see the image in Photoshop as they will see it in PTE.

I do know a little about Photoshop and image manipulation and seeing the image at the size it will project on screen or print is vital for good work.

My point is we don’t need to know that mumbo jumbo about resolution. Its fine for those that like all that stuff, but 95% of people want to produce a slide show or a print, not have to consider mathematics.

So, we should be saying to newer converts to digital that to create a PTE image set the PPI at 72 and the width at 1024 and tick the resample box. For a print, don’t select the resample box. There two and a bit sentences.

The biggest problem with all things digital and the world wide web is the worst, is that those who understand the processes assume everyone else needs to or wants to. I can’t describe how my car engine and all the other components work, but I manage to get it from one end of the country to the other.

Lets keep things simple.

BB

[Ian]

I'm absolutely in favour of keeping things simple, which is why I always advise people to forget about the 72 dpi nonsense and just use a fixed pixel dimension.

Using Photoshop, there is real purpose in using any combination of "dpi" and "inches" as it isn't really necessary. All this does is introduce an extra step into the workflow, and causes one of the biggest confusions that a new user can get trapped by!

When you hit "Ctrl+0" in Photoshop it doesn't expand the image to 100% of its pixel size, but instead uses an arbitrary percentage in order to fill the available screen size within the Photoshop window. This will be depend on the monitor resolution and hence isn't fixed. The dpi setting doesn't affect this at all - try it and see!

Double-clicking the zoom tool will change the image to 100% (ie 1:1 pixel display) and this is a more accurate representation of how a 1024x768 image will appear in the show.

If I'm reading your previous post correctly, I do think we're talking at cross puropses! You mention using a 13"x9" image @300 dpi. By my reckoning this would have to be 3900 pixels wide by

2700 pixels high. Fine for printing, but way too big for acceptable screen display! I would always advocate making a second copy at 1024 pixel width for use in PTE, and then all of the confusing dpi and inch calculations simply don't apply!

This topic has strayed well off the original post, but has sure opened up an interesting debate!

On another note, I would tend to agree with Malcolm's point somewhere above that the introduction of zoom and pan may very well change all the rules! If the zoom facility actually uses available pixels, then it could vey well re-sample the jpg for more picture information as it zooms into the view. In this case, then it would make sense to use a larger image so that the picture stays sharp throughout its zoom.

If on the other hand it simply enlarges the image by interpolation then the quality would suffer.

I guess we'll all know in due course!

Ian

[JRR]

Ian/Barry:

I was the one who dragged the thread off topic when I replied to Deb saying don't bother touching the resolution when sizing.

I expected that I would get a reaction to that statement as we always have in the past, (and I expect we will in the future) but I believe in giving the best advice I can.

I am with Ian on this one, forget about the resolution.

For the doutbing thomases, do as I suggested in my reply to Ronniebootwest, just try it and compare.

When I help someone get started with Digital Photography, my first lesson is the editing software is pixel size, print size, resolution and file size.

It is a difficult concept at times, but once understood it will help many times as they work through their images for printing and screen display etc etc

Scantips, as as been referred to here is an excellent source

[Ronniebootwest]

Of course the '72 dpi' issue will run and run, especially if if people persist in making it all sound so complicated! I think that Barry is correct in saying that it is the file size that we are concerned with here. If you have an image sized for 1024x768 pixels and a resolution of 300 you wil have a file size of 2.25m. The same image set to a resolution of 72 will reduce that file size to just 132kb - much smaller.

The other point to note is that leaving an image resolution set to 300 will make it much easier for people to take a screenshot and 'steal' the image.

As far as PTE is concerned, I will continue to advise people to use the '72' resolution because I do not agree that the concept is a myth.

Ron West