Grainy?
Tesselator
"Smoothy" <bigvahid...@hotmail.com> wrote in message news:YCeDa.3738$IR1.3...@news20.bellglobal.com...
> Hi all,
>
> Do you think that this picture is a little grainy?
> And if yes, what do you think is the reason?
>
> You can take a look at the Metadata...
>
Well, I donno what may be said about posting Images here...
But I can tell you that any grain that might have been noticable
in the original was mushed and squashed when you Jpegged it.
What is that, like level 5 or 6?
Tesselator
"Smoothy" <bigvahid...@hotmail.com> wrote in message news:MCpDa.3833$V77.4...@news20.bellglobal.com...
> I can't see my own post!
> Did you see the attached file to it? or was it removed?
>
> I didn't do any compression on the original pic, just resized it from
> 1600*1200 to 1024*768.
>
> Anyways, this one is a crop of the original 1600*1200 image.
> What do you think about this?
I think we're gonna get yelled at for posting binary images to
a non-binary newsgroup. Can't you put up a little temporary
FTP site or post it on someplace like Nikon.com It /was/ taken
with a Nikon alter all...
> It is in daylight, and with ISO set to 100 (automatically of course), why
> should it be so grainy?
Again this is a Jpeg image and is compressed at 15:7 which is severe
enough to flatten whatever noice you may be talking about.
I wonder is your viewer software isn't set to dither mode on a 16bit
display or somethng?
Really the jpeg error is so severe it drowneds out any other anomalies
that may have existed before.
> Thanks Tesselator.
You're welcome. But think of another way to post images. The newsgroup
folks usually don't dig it unless the word "binaries" is contained some-
where in the channel name. Like: alt.binaries.dev.digital-camera or
something.
If you can't find a place to post let me know and I'll put up an FTP
for you and others wanting to post example shots.
Smoothy
I put all the pictures in this address:
http://www3.sympatico.ca/vahid.afra/
And again you are right, when saving the crop, the JPEG compression was on
65%,
I thought it is on 100%.
But the pictures which are uploaded on the above address, are all original.
Now I'd appreciate your comment about them.
I myself think that all of them are grainy:
Building Picture: the walls, ceiling, that parked car, ...
Falls Picture: the sky and water
Flowers Picture: all over the picture I notice grains...
Tree Picture: the leaves
I wonder why it should be like this, they are all taken in daylight, so
there should be no effect like
image noise (which usually noticable in night pictures with higher ISO).
This camera (Nikon Coolpix 2100) IS SUPPOSED to have sharp and crisp images!
And thanks for your explanation about posting binaries.
--
"Tesselator" <jimm...@hotmail.com> wrote in message
news:bblotg$76r$1...@catv02.starcat.ne.jp...
Tesselator
"Smoothy" <bigvahid...@hotmail.com> wrote in message news:%czDa.11757$HG5.5...@news20.bellglobal.com...
> You are right, I didn't know it's not allowed to post images in this group.
> I put all the pictures in this address:
> http://www3.sympatico.ca/vahid.afra/
>
> And again you are right, when saving the crop, the JPEG compression was on
> 65%,
> I thought it is on 100%.
> But the pictures which are uploaded on the above address, are all original.
If original then the camera compressed it.
http://www3.sympatico.ca/vahid.afra/building.jpg is still 15.7 compression
ratio. I believe the 2100 has 3 levels of JPEG and one level of uncompressed.
You had the setting on "Normal" right? That's 15.7 jpeg.
O :-)
> Now I'd appreciate your comment about them.
> I myself think that all of them are grainy:
> Building Picture: the walls, ceiling, that parked car, ...
I'd have to see an uncompressed version side by side to be sure (impossible now)
but as just a guess I'd say 70% of the noise you're seeing in that image was
introduced my the compression algorithm. /I Think/ the other 30% or so is due
to the fact that you've maxed out the dynamic range of the CCD with that particular
exposure (err, picture). See how the sky is looking over exposed yet the areas
under cars and even on the side of one car are underexposed? That.
I said "dynamic range of the CCD" and for this explaination that could suffice
even though the actual science is a little different.
> Falls Picture: the sky and water
> Flowers Picture: all over the picture I notice grains...
> Tree Picture: the leaves
The noise you see in these shots is 99.5% due to jpeg compression error.
The 1200x1600x24 shots would be about 5.7megs if uncompressed and the
1024x768x24 shot of the flowers would be about 2.3 megs.
> I wonder why it should be like this, they are all taken in daylight, so
> there should be no effect like
> image noise (which usually noticable in night pictures with higher ISO).
> This camera (Nikon Coolpix 2100) IS SUPPOSED to have sharp and crisp images!
Yup I have a couple of coolpix too. They /are/ nice. The shot you picked
there is one of the toughest to get right... IF it can even be done.
The sun has set behind that building but is still illuminating the BG sky
and leaving the building face in the shadows. Notice how the lamp-posts
are lit up? I'ld say the camera did the best job possible under the
circumstances. Ofcourse it /could/ be a sun-rise causing the same condition
but it looked to me as if people were going not comming so I assumed dusk.
> And thanks for your explanation about posting binaries.
>
NP.
O :-)
Smoothy
Thanks for your reply.
CP2100 has only two levels of compression at 1600*1200, which are Fine (1:4)
and
Normal (1:8).
And yes, I took all of them at "Normal" setting.
About the building, now I understand.
I think I expected a little too much of my camera! ;)
The bright sky at the top, sun behind the building, and...
> as if people were going not comming
Is it a movie or a still picture?!
JK! You're right, and it was sunset, a cloudy sunset to be more specific.
Now if you don't mind, I can't understand something about these compressin
ratios:
The camera manual says that "Fine" is a 4:1 compression, well.
But what this number has to do with the compression ratio I see in the image
properties?
Numbers like 15.7, 9.8, 10.0, ...
The least compression I could get from my camera (1600*1200, Fine) was 7.4.
But even with the quality set to Fine, different pictures taken with the
camera, have different
compression ratios shown in my image viewing software; something between 7.4
and 10.0.
What's the reason for this?
Cheers. :o)
--
"Tesselator" <jimm...@hotmail.com> wrote in message
news:bbn68i$peu$1...@catv02.starcat.ne.jp...
Tesselator
"Smoothy" <bigvahid...@hotmail.com> wrote in message news:nIJDa.7933$VS5.6...@news20.bellglobal.com...
> Hey Tesselator,
>
> Thanks for your reply.
> CP2100 has only two levels of compression at 1600*1200, which are Fine (1:4)
> and
> Normal (1:8).
> And yes, I took all of them at "Normal" setting.
>
> About the building, now I understand.
> I think I expected a little too much of my camera! ;)
> The bright sky at the top, sun behind the building, and...
> > as if people were going not comming
> Is it a movie or a still picture?!
> JK! You're right, and it was sunset, a cloudy sunset to be more specific.
>
> Now if you don't mind, I can't understand something about these compressin
> ratios:
> The camera manual says that "Fine" is a 4:1 compression, well.
> But what this number has to do with the compression ratio I see in the image
> properties?
> Numbers like 15.7, 9.8, 10.0, ...
> The least compression I could get from my camera (1600*1200, Fine) was 7.4.
> But even with the quality set to Fine, different pictures taken with the
> camera, have different
> compression ratios shown in my image viewing software; something between 7.4
> and 10.0.
> What's the reason for this?
>
>
I don't know really... Maybe someone who does will answer up. Maybe that
number is the multiple of the ammount of total files size reduction or
something. So in that one case it's 15.7 times smaller than if uncompressed.
Let's see: Uncompressed Building.jpg would be 1600x1200x3=5760000 (Bytes)
but in Jpeg it's 365912 (bytes). Let's try: 365912x15.7=5744818
Yup, close enough. I bet that's it. This would be different from the
"Quality" setting we're used to using in Photoshop and others.
Reinder Mulder
picture of a piece of blank paper the same jpg-setting "Fine" gives a
much higher compression ratio than say a picture of trees with lots of
detail). The setting determines the amount of quality-loss you're
willing to accept, not the resulting compression ratio.
Reinder
Smoothy
I got my answer completely.
--
"Smoothy" <bigvahid...@hotmail.com> wrote in message
news:nIJDa.7933$VS5.6...@news20.bellglobal.com...