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SD800 edge blurries solved?

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Dr. Leonard

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From what I've read, and correct me if I'm wrong, the aspect ratio varies from 3/2 for DSLRs to 4/3 for compacts. The aspect ratio for the SD800 is 4/3 or 10.67 X 8 in. To get to 8 X 10, the edges are cropped. I've tried this on a SD800 sample (from a site I can't remember - dresource?) and it works - the blurry edges are now gone.
 
No. He's saying if you crop out the corners, you won't have a corner softness problem.
 
Dr. Leonard said:
richarddd said:
No. He's saying if you crop out the corners, you won't have a
corner softness problem.
Click to expand...
Right, and if you crop he 4/3 to 8 X 10, the long edges are cropped
out. Problem solved. Just don't make any 5 X 7 or 4 X 6.
Click to expand...
It works on those two. On an 8x10 (landscape format), you have to crop the left and right edges. To make a 5x7 or 4x6, you have to crop the bottom and top edges. Anyway you look at it, the corners end up gone in prints.

--
Lee Jay
(see profile for equipment)
 
I suppose what he's saying is that that for anyone who prints in std format 6x4, 7x5 (no that corner softness is an issue at those sizes anyway) and 10x8 (corner softness come into play) that the corners have to be cropped at those sizes as digital print default sizes are slightly larger. Obviously if you are just a pixel peeper and hardly ever print it isn't going to be any real help. But if the corner softness is such a big issue to most people then they'll either go for an non 28mm camera or a Ricoh R5 or FX Panny and suffer from generally poorer all round pictures with too much NR!
 
Stephen said:
So what's the point of having a wide angle shot

Cheers
Stephen
Click to expand...
Going from a 28mm 8 X 10.66 to 8 X 10 will still be "wide angle", at least compared to the more usual (in this camera class) 35-38mm. Probably somebody can actually calculate the "new" mm. As a very rough estimate based on the reduction in total area, I guess the new focal length would be about 29 to 29.5 mm.
 
richardc77 said:
I suppose what he's saying is that that for anyone who prints in
std format 6x4, 7x5 (no that corner softness is an issue at those
sizes anyway) and 10x8 (corner softness come into play) that the
corners have to be cropped at those sizes as digital print default
sizes are slightly larger. Obviously if you are just a pixel peeper
and hardly ever print it isn't going to be any real help. But if
the corner softness is such a big issue to most people then they'll
either go for an non 28mm camera or a Ricoh R5 or FX Panny and
suffer from generally poorer all round pictures with too much NR!
Click to expand...
Exactly right. I always import photos into Photoshop and select 8 X 10 in the Print dialog box. This gives me an exact 8 X 10 so the edges are automatically cropped. Why 8 X 10? Two reasons. I can't find 8 X 10.66 frames to display my photos and when I sometimes order prints from Kodak, there is no 8 X 10.66 option. And as you say, at smaller print sizes, corner softness is not an issue.

I had a Panny FX-01 but returned it because of image destroying noise at ISO 400. The Ricoh has some banding and other problems that have been reported in the forums and also has no US distributor. We are not yet in heaven.
 
Dr. Leonard said:
Stephen said:
So what's the point of having a wide angle shot

Cheers
Stephen
Click to expand...
Going from a 28mm 8 X 10.66 to 8 X 10 will still be "wide angle",
at least compared to the more usual (in this camera class) 35-38mm.
Probably somebody can actually calculate the "new" mm. As a very
rough estimate based on the reduction in total area, I guess the
new focal length would be about 29 to 29.5 mm.
Click to expand...
This will sound a little crazy but it's right.

The SD800IS, cropped to 8x10 will produce an 8x10 that's as wide as an 8x10 from a 25.5mm lens on a 35mm-format camera.

Let's see who can figure that one out!!!

;-)

--
Lee Jay
(see profile for equipment)
 
Lee Jay said:
This will sound a little crazy but it's right.

The SD800IS, cropped to 8x10 will produce an 8x10 that's as wide as
an 8x10 from a 25.5mm lens on a 35mm-format camera.

Let's see who can figure that one out!!!

;-)

--
Lee Jay
(see profile for equipment)
Click to expand...
You're giving me a headache.
 
"The SD800IS, cropped to 8x10 will produce an 8x10 that's as wide as
Dr. Leonard said:
an 8x10 from a 25.5mm lens on a 35mm-format camera."
Click to expand...
Cropping (making narrower) a 28mm wide field of view pic equals a pic from an even wider lens-- 25.5mm ?
Forget the headache, how about a migraine!
 
That is probably because 35mm photo gets cropped even more
(compared to sd800 photo) when printing 8x10?
 
g6user said:
That is probably because 35mm photo gets cropped even more
(compared to sd800 photo) when printing 8x10?
Click to expand...
That is the main reason, of two important ones. Well done!

The sensor in the SD800IS is 5.76mm in horizontal dimension. The lens is 4.6mm in focal length at the wide end. A 35mm film frame is 36mm in horizontal dimension. So the crop factor is really 36mm/5.76mm = 6.25.

6.25 * 4.6mm = 28.75mm 35mm equivalent. 28mm is the diagonal equivalence which is different because the SD800 is 4:3 ratio sensor while 35mm is a 3:2 ratio. When you crop them both to 8x10, you end up with both as 4:5 ratio sensors.

If you crop the SD800 to 4:5 the sensor becomes 5.4mm wide (down from 5.76mm) while the 35mm sensor becomes 30mm wide (down from 36mm). The crop factor is then 30mm/5.4mm = 5.56 - a lower crop factor than the "6" used for diagonal equivalence or the 6.25 used for horizontal equivalence of the whole sensors.

5.56 * 4.6mm=25.6mm, 35mm equivalent.

--
Lee Jay
(see profile for equipment)
 
ljfinger said:
g6user said:
That is probably because 35mm photo gets cropped even more
(compared to sd800 photo) when printing 8x10?
Click to expand...
That is the main reason, of two important ones. Well done!

The sensor in the SD800IS is 5.76mm in horizontal dimension. The
lens is 4.6mm in focal length at the wide end. A 35mm film frame
is 36mm in horizontal dimension. So the crop factor is really
36mm/5.76mm = 6.25.

6.25 * 4.6mm = 28.75mm 35mm equivalent. 28mm is the diagonal
equivalence which is different because the SD800 is 4:3 ratio
sensor while 35mm is a 3:2 ratio. When you crop them both to 8x10,
you end up with both as 4:5 ratio sensors.

If you crop the SD800 to 4:5 the sensor becomes 5.4mm wide (down
from 5.76mm) while the 35mm sensor becomes 30mm wide (down from
36mm). The crop factor is then 30mm/5.4mm = 5.56 - a lower crop
factor than the "6" used for diagonal equivalence or the 6.25 used
for horizontal equivalence of the whole sensors.

5.56 * 4.6mm=25.6mm, 35mm equivalent.
Click to expand...
There's no answer to that! I'll read it again.
 
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