Rotate image without perspective change?

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Guest

Hi all,

Probably a much repeated question, but how can I be sure of keeping the
original perspective when I rotate an image - from a scanner or camera say.

It seems that whatever prog I happen to rotate them with they always get
taller when rotated. I now find that even when I adjust the perspective so
that it looks right, when I save it, it reverts to the over tall rotated
perspective.

As my HP scanner size settings are mostly wider than long, this makes the
scan faster, but does mean many images need to be rotated, and then somehow
tricked back into the right perspective.

How can one insure that one preserves the proper proportions?

Regards,

S
 
spamlet said:
Hi all,

Probably a much repeated question, but how can I be sure of keeping
the original perspective when I rotate an image - from a scanner or
camera say.
It seems that whatever prog I happen to rotate them with they always
get taller when rotated. I now find that even when I adjust the
perspective so that it looks right, when I save it, it reverts to the
over tall rotated perspective.

As my HP scanner size settings are mostly wider than long, this makes
the scan faster, but does mean many images need to be rotated, and
then somehow tricked back into the right perspective.

How can one insure that one preserves the proper proportions?

Regards,

S
Click to expand...
=======================================
There are two orientations...Portrait and Landscape.
If you rotate an image that is in Portrait orientation
90 degrees...the result will be an image in Landscape
orientation. That is normal and if you prefer all images
to have the same orientation...you will have to crop them.

If you are saying the images become distorted (stretched
or compressed) when you rotate them...that is a different
issue.

--

John Inzer
MS Picture It! -
Digital Image MVP

Digital Image
Highlights and FAQs
http://tinyurl.com/aczzp

Notice
This is not tech support
I am a volunteer

Solutions that work for
me may not work for you

Proceed at your own risk
 
John Inzer said:
=======================================
There are two orientations...Portrait and Landscape.
If you rotate an image that is in Portrait orientation
90 degrees...the result will be an image in Landscape
orientation. That is normal and if you prefer all images
to have the same orientation...you will have to crop them.

If you are saying the images become distorted (stretched
or compressed) when you rotate them...that is a different
issue.

--

John Inzer
MS Picture It! -
Digital Image MVP

Digital Image
Highlights and FAQs
http://tinyurl.com/aczzp
Click to expand...


Hi John,

When you say 'portrait' or 'landscape', do you imply that rotating the image
is actually rotating the page that it is on rather than the image itself, or
are we talking about say, 'a portrait image on a landscape page'? Do my
landscape and portrait default pages have different perspectives? All
rather confusing!

Anyhow, I just tried opening the scanned pic in MS Photo Editor, and it
still looks too tall, but when I go to resize, the measurements it gives are
the same as on the original that was scanned. Actually measuring the screen
image with a ruler I see that the original had an aspect ratio of .68, but
appears as .64. The image did print out the same size as the original
though.

If it is the display, I don't understand why an image that was not rotated
looks the right size? (Possibly a slightly foreshortened picture does not
look as bad as a stretched one.)

So lets hear more about that 'different issue' if you have it.

Thanks for responding,

S
 
spamlet said:
When you say 'portrait' or 'landscape', do you imply that rotating
the image is actually rotating the page that it is on rather than the
image itself, or are we talking about say, 'a portrait image on a
landscape page'? Do my landscape and portrait default pages have
different perspectives? All rather confusing!
Click to expand...
==========================
Yes, the page is rotated. I think you are
expecting all images to be Landscape
orientation (wider that they are tall) but
that is just not the reality of digital images.
You will find that you always have an
assortment of both.
==========================
Anyhow, I just tried opening the scanned pic in MS Photo Editor, and
it still looks too tall, but when I go to resize, the measurements it
gives are the same as on the original that was scanned. Actually
measuring the screen image with a ruler I see that the original had
an aspect ratio of .68, but appears as .64. The image did print out
the same size as the original though.

If it is the display, I don't understand why an image that was not
rotated looks the right size? (Possibly a slightly foreshortened
picture does not look as bad as a stretched one.)

So lets hear more about that 'different issue' if you have it.
Click to expand...
==========================
Since you are not experiencing distortion...
the "different issue does not apply.
==========================
Thanks for responding,

S
Click to expand...
==========================
You're welcome.

--

John Inzer
MS Picture It! -
Digital Image MVP

Digital Image
Highlights and FAQs
http://tinyurl.com/aczzp

Notice
This is not tech support
I am a volunteer

Solutions that work for
me may not work for you

Proceed at your own risk
 
John Inzer said:
Yes, the page is rotated. I think you are
expecting all images to be Landscape
orientation (wider that they are tall) but
that is just not the reality of digital images.
You will find that you always have an
assortment of both.
Click to expand...

Er, obviously I'm not expecting all my pics to have the same orientation or
I would not have been needing to rotate them on the pc to compensate for me
turning the camera! I would just like them not to appear longer/taller when
they are turned.
Since you are not experiencing distortion...
the "different issue does not apply.
Click to expand...


So you are saying that things are meant to look distorted when one rotates
the page!

Don't worry, I'll look into it myself: discovering that the print is the
right size, gives me something to go on.

Cheers,

S
 
spamlet said:
Er, obviously I'm not expecting all my pics to have the same
orientation or I would not have been needing to rotate them on the pc
to compensate for me turning the camera! I would just like them not
to appear longer/taller when they are turned.



So you are saying that things are meant to look distorted when one
rotates the page!

Don't worry, I'll look into it myself: discovering that the print is
the right size, gives me something to go on.

Cheers,

S
Click to expand...
==================================
I apologize for attempting to assist you...it is
quite clear that we are not communicating.

I hope you find the information you are seeking.

--

John Inzer
MS Picture It! -
Digital Image MVP

Digital Image
Highlights and FAQs
http://tinyurl.com/aczzp

Notice
This is not tech support
I am a volunteer

Solutions that work for
me may not work for you

Proceed at your own risk
 
The answer is simple.
You are right, the print will be the right size and perspective. However,
look at the print, it is not rotated. You rotate the print by hand to see
the picture.
You can do the same thing if you have a monitor with a pivot. You rotate the
monitor, not the picture. Same as rotating a print!
If you can't rotate the monitor, you rotate the picture. The viewing
software must now fit the same aspect ratio from the long side (width) to
the short side (height) of your monitor. So, in effect it "zooms in" but
still keeps everything in the picture in proportion.
The only time you can rotate and not have this change in size or perspective
is if you have a camera or scan a picture with and aspect ratio of 1.0, that
is a perfect square.
 
Thanks for the feedback Yves (and apologies to John for sounding
ungrateful),

Actually, the print is rotated but still the right perspective:
I scanned it in landscape to reduce scanning time and file size; then
rotated it on pc to its proper upright position, whereupon it looked too
tall. Then printing it, it came out in the corrected upright position, with
the right perspective.

So I would say the monitor needs adjusting so that the x & y scales are the
same.
Another alternative is that, say Photo Editor, has an underlying grid which
is not square (Which seems to be the way Word comes by the way - and, boy
does the setting take some finding!).

I have not looked into the screen set up yet, but will let you know.
Thanks again,

S
 
You cannot set your monitor for the x and y scales to be the same.
But, as you wrote, let us know if you can.
 
You cannot set your monitor for the x and y scales to be the same.
But, as you wrote, let us know if you can.









- Show quoted text -
Click to expand...

I might be missing something here, but isn't the obvious answer that
it's a problem with the resolution of your monitor? E.g. if the
native res is something like 1440x768, and you have it set to 1024x768
or similar?
Find out the native resolution of your monitor (or post make/model
here) and check your desktop settings are correct...

Ric
 
ric said:
I might be missing something here, but isn't the obvious answer that
it's a problem with the resolution of your monitor? E.g. if the
native res is something like 1440x768, and you have it set to 1024x768
or similar?
Find out the native resolution of your monitor (or post make/model
here) and check your desktop settings are correct...

Ric
Click to expand...

Hi Ric,

The Dell E171FP monitor came with our Dell system.

The settings buttons on the front, have toggles for centring the screen and
for moving the settings menu about, but not, apparently, a simple picture
height adjustment - which would probably have done the job!

The menu furnishes me with the info that I am running it at 1024 x 768 and
refresh at 75Hz; whereas it says the 'optimum' is 1280 x 1024 at 60Hz. A
quick dividing, gives the different aspect ratios of .75 v .8 - which seems
remarkably similar to the difference I am noting in the pictures. So it
looks like you are on the case.

Going into the desktop properties menus I find that one tag on the advanced
properties has the title 'Can't find requested string'. This looks like the
one that should have had the monitor information on it...

The XP monitor resolution settings slider gives me the option of 1280x1024,
and this would give me oodles of desktop room, but tiny icons, and dinky
windows with tiny writing in. There does not seem to be another setting
with the same ratio as this 'optimum' (Or is there somewhere to specify
measurements not on the graduated scale?) - though I do discover that I can
have the same ratio as current, but with more room, and only a small loss of
size, with the 1152 x 864 setting. But this would, presumably still give me
the distortion on rotation.

Further delving and I found the DPI settings with an option to increase from
96 to 120 if my icons are 'too small' with the optimum, screen resolution.
Anti intuitive as this is - I would have expected more pixels to the inch to
make things even smaller! - I gave it a go, but there was still no way I
could get all the windows and dialogues a decent size and with legible text
on, no matter how much I tweaked the customise desktop settings. Had to
system restore in the end...

What would have been wrong with having a simple TV type picture height
screw,
one has to ask!

Thanks for your interest.

S
 
spamlet said:
Hi Ric,

The Dell E171FP monitor came with our Dell system.

The settings buttons on the front, have toggles for centring the screen and
for moving the settings menu about, but not, apparently, a simple picture
height adjustment - which would probably have done the job!

The menu furnishes me with the info that I am running it at 1024 x 768 and
refresh at 75Hz; whereas it says the 'optimum' is 1280 x 1024 at 60Hz. A
quick dividing, gives the different aspect ratios of .75 v .8 - which seems
remarkably similar to the difference I am noting in the pictures. So it
looks like you are on the case.

Going into the desktop properties menus I find that one tag on the advanced
properties has the title 'Can't find requested string'. This looks like the
one that should have had the monitor information on it...

The XP monitor resolution settings slider gives me the option of 1280x1024,
and this would give me oodles of desktop room, but tiny icons, and dinky
windows with tiny writing in. There does not seem to be another setting
with the same ratio as this 'optimum' (Or is there somewhere to specify
measurements not on the graduated scale?) - though I do discover that I can
have the same ratio as current, but with more room, and only a small loss of
size, with the 1152 x 864 setting. But this would, presumably still give me
the distortion on rotation.

Further delving and I found the DPI settings with an option to increase from
96 to 120 if my icons are 'too small' with the optimum, screen resolution.
Anti intuitive as this is - I would have expected more pixels to the inch to
make things even smaller! - I gave it a go, but there was still no way I
could get all the windows and dialogues a decent size and with legible text
on, no matter how much I tweaked the customise desktop settings. Had to
system restore in the end...

What would have been wrong with having a simple TV type picture height
screw,
one has to ask!
Click to expand...

These are the days of digital displays, and, although they can resample
from one size to another, the best results are always obtained by using
the "native" resolution of the monitor--in your case 1280x1024.

The XP desktop "Properties" box (right-click on an empty space on the
desktop), under the tab marked "Appearance", has a "Font size" selection
box offering "Normal", "Large Fonts", and "Extra Large Fonts". If you
select either of the latter two selections you should get a readable
desktop display.

BTW, native resolution will *almost always* be perfectly square pixels.

-michael

NadaPong: Network game demo for Apple II computers!
Home page: http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."
 
Michael J. Mahon said:
These are the days of digital displays, and, although they can resample
from one size to another, the best results are always obtained by using
the "native" resolution of the monitor--in your case 1280x1024.

The XP desktop "Properties" box (right-click on an empty space on the
desktop), under the tab marked "Appearance", has a "Font size" selection
box offering "Normal", "Large Fonts", and "Extra Large Fonts". If you
select either of the latter two selections you should get a readable
desktop display.

BTW, native resolution will *almost always* be perfectly square pixels.

-michael

NadaPong: Network game demo for Apple II computers!
Home page: http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."
Click to expand...


Thanks Michael, but I've been through all that:

Every different programme responds differently to changes in text size, and
this is not related to accompanying changes in window size. Increasing the
font size makes some fonts more legible and some fonts less. The trouble
with the 'optimum' is that the letters are all very fine and difficult to
resolve unless one boldens them, or makes them much too big for the windows
in which they run. The 'advanced' options do not provide any facility for
adjusting all the various window sizes when one adjusts the text either.

On the face of it, upping the DPI setting ought to do the job for
everything; and increasing to 150% does roughly duplicate the original
window sizes, but then all the text looks awful and much too crowded in the
windows - for example: messages in O or OE are all crammed together.

I've tried quite a few hours of experiments on this, and always end up
having to do a system restore.
Shame, because the only things that do behave themselves at the 'optimum'
are the pictures, which do indeed then maintain their perspective on
rotation!

I did discover that the dedicated Dell monitor driver had not been loaded at
system set up. But adding this has unfortunately, made no difference.

Nevertheless: thanks for your interest.

Cheers,

S
 
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