Sigma sd14 noise at ISO-100

miketuthill · Mar 13, 2008

Just for clarity; were you overexposing the SD14 shots by .7 EV or so for this test?

alkonavt said:
Thank you for reply!
Yes, it will be great for me to get some simple test X3F-s from other
SD-14. If somebody will publish them it will be great help for me.
Just several black frames from sd14 on different shutter speeds and
ISO will be very helpful.
It seems that I will need to go to court, to get my money back, or
get other non defective camera(I preffer camera)
Russian Sigma dealers do not like to take sold things back...

With regards,
alkonavt

--
http://www.pbase.com/miketuthill

alkonavt · Mar 13, 2008

No. At first I made several photos. And saw a noise in human hair. There was very little exposure mistake, not more then 0.7Ev. A remembered, that SD10 images in the same conditions has no problems. So, I made test in hard conditions for both cameras. SD10 was much better.

Now I can show X3Fs. Thank's for daksland.com

miketuthill · Mar 13, 2008

Perhaps you're misunderstanding what other's have been telling you. In order to fairly compare the noise on the 2 cameras you need to apply a little underexposure on the SD10 and a little overexposure on the SD14. That's just the nature of the 2 different cameras. If you don't overexpose with the SD14 you will end up with more noise under certain conditions ie. shadow areas.

alkonavt said:
No. At first I made several photos. And saw a noise in human hair.
There was very little exposure mistake, not more then 0.7Ev. A
remembered, that SD10 images in the same conditions has no problems.
So, I made test in hard conditions for both cameras. SD10 was much
better.

Now I can show X3Fs. Thank's for daksland.com

SD10 test scene.
http://daksland.com/userfiles/private/x3f/IMG05848.X3F

SD10 black frames on ISO 100, 200, 400, 800
http://daksland.com/userfiles/private/x3f/IMG05837.X3F
http://daksland.com/userfiles/private/x3f/IMG05838.X3F
http://daksland.com/userfiles/private/x3f/IMG05839.X3F
http://daksland.com/userfiles/private/x3f/IMG05840.X3F

SD14 test scene.
http://daksland.com/userfiles/private/x3f/SDIM0474.X3F

SD14 black frames on ISO 100
http://daksland.com/userfiles/private/x3f/SDIM0475.X3F
http://daksland.com/userfiles/private/x3f/SDIM0476.X3F

So, any one can play with them now, if he want...

--
http://www.pbase.com/miketuthill

alkonavt · Mar 13, 2008

miketuthill said:
Perhaps you're misunderstanding what other's have been telling you.
In order to fairly compare the noise on the 2 cameras you need to
apply a little underexposure on the SD10 and a little overexposure on
the SD14. That's just the nature of the 2 different cameras. If you
don't overexpose with the SD14 you will end up with more noise under
certain conditions ie. shadow areas.

If we overexposure - we possible will lose details in highlights. Yes shadows will be better exposed, and noise will be masked. It will works perfectly, if our scene have lo dynamic range (

But what such thing as effective dynamic range? If we try to take a picture of hi dynamic range scene (9Ev or more)? So, we will not be able to set exposure to shoot all scene and make HDR image after it. Or just reduce contrast. We will get noise in shadows.

As for me - effective dynamic range is one of the main characteristics of DSLR. I love my SD10 for really great dynamic range. And I do not think that step backward in this is acceptable.

As I see, SD14 effective DR is very low, it's between 7-8Ev, against 10-11Ev of SD10.

Additionally, wide dynamic range can help us to correct our errors. Sometimes we get a great underexposure, when using external flash. It can be not fully charged, when we shoot. So, it will not shoot at full power. Sometimes, such pictures are best in session. Using SD10 we can correct them, using SD14 - no. They will go in the bin.

miketuthill · Mar 13, 2008

alkonavt said:
miketuthill said:

Perhaps you're misunderstanding what other's have been telling you.
In order to fairly compare the noise on the 2 cameras you need to
apply a little underexposure on the SD10 and a little overexposure on
the SD14. That's just the nature of the 2 different cameras. If you
don't overexpose with the SD14 you will end up with more noise under
certain conditions ie. shadow areas.

Click to expand...

If we overexposure - we possible will lose details in highlights. Yes
shadows will be better exposed, and noise will be masked. It will
works perfectly, if our scene have lo dynamic range (
But what such thing as effective dynamic range? If we try to take a
picture of hi dynamic range scene (9Ev or more)? So, we will not be
able to set exposure to shoot all scene and make HDR image after it.
Or just reduce contrast. We will get noise in shadows.

Experience has shown that you won't lose highlight detail with moderate overexposing on the SD14. Look at it this way; one could say that -.3 EV on SD10 = +.7 EV on the SD14. The meters are different so the exposure compensation needed is different. Now it would be nice if they could calibrate the meter properly through firmware.

--
http://www.pbase.com/miketuthill

Guido FORRIER · Mar 13, 2008

I agree with miketuthill , and others ....

i made a lot of testshots in studio an i use the results in real situations . So i can have decent 800 iso shots , sometimes 1600 iso .
I use mostly Raw Developer for the 50-100 iso shots
Above 100 iso i use spp 3.1 (mac) : much better than the older spp.
I also mostly use autobracketing 0,3 ev +
50 iso +0 ev
100-200-400 iso : +0,7 ev
800-1600 iso : + 1 ev .
For best quality and hdr : use 50 iso.
Greetings ,
Guido

alkonavt · Mar 13, 2008

miketuthill said:
Experience has shown that you won't lose highlight detail with
moderate overexposing on the SD14. Look at it this way; one could
say that -.3 EV on SD10 = +.7 EV on the SD14. The meters are
different so the exposure compensation needed is different. Now it
would be nice if they could calibrate the meter properly through
firmware.

I think we have some misunderstanding...

I talking not about exponometer... I know that sigma's exponometers are strange

In my examples I have not use exponometer at all. I shoot in manual mode with same exposure values for both cameras. Using same ISO.
I used
F=2.8, S=1/15s, ISO 100 for SD10
and
F=2.8, S=1/15s, ISO 100 for SD14
Exactly the same.
Exponometer of both cameras was not used.
I was testing the sensor.
After that I made the same processing for SD10 and SD14 images.
Using same SPP2.3 settings (all adjustment controls in 0(zero)).
Using same levels correction in Adobe Photoshop. (Just expand levels 2-50)
After that - only crop and resize.

As other test - i shoot 2 frames with black lens cover.

And I saw: SD10 signal/noise ratio less than 1024/1. And sd14 Signal/noise ratio is about (16/1 - 8/1).
It's awful result. It's differs from SD10 more than 64 times!
Expocorection will not help in this situation. Really.

Thank you for you attention,
Best regards,
alkonavt

miketuthill · Mar 13, 2008

We seem to be talking around one another here

What I'm trying to convey to you is that you should ignore bad results that you get with no EV compensation and do your tests using +.7 EV as otherwise you're essentially complaining about noise that appears when the shot is underexposed. Just about any camera will have noise problems with underexposures and by not compensating for the inaccurate meter you are, in effect, underexposing.

alkonavt said:
alkonavt said:

Experience has shown that you won't lose highlight detail with
moderate overexposing on the SD14. Look at it this way; one could
say that -.3 EV on SD10 = +.7 EV on the SD14. The meters are
different so the exposure compensation needed is different. Now it
would be nice if they could calibrate the meter properly through
firmware.

Click to expand...

I think we have some misunderstanding...
I talking not about exponometer... I know that sigma's exponometers
are strange
In my examples I have not use exponometer at all. I shoot in manual
mode with same exposure values for both cameras. Using same ISO.
I used
F=2.8, S=1/15s, ISO 100 for SD10
and
F=2.8, S=1/15s, ISO 100 for SD14
Exactly the same.
Exponometer of both cameras was not used.
I was testing the sensor.
After that I made the same processing for SD10 and SD14 images.
Using same SPP2.3 settings (all adjustment controls in 0(zero)).
Using same levels correction in Adobe Photoshop. (Just expand levels
2-50)
After that - only crop and resize.

As other test - i shoot 2 frames with black lens cover.
And I saw: SD10 signal/noise ratio less than 1024/1. And sd14
Signal/noise ratio is about (16/1 - 8/1).
It's awful result. It's differs from SD10 more than 64 times!
Expocorection will not help in this situation. Really.

Thank you for you attention,
Best regards,
alkonavt

--
http://www.pbase.com/miketuthill

Roland Karlsson · Mar 13, 2008

miketuthill said:
We seem to be talking around one another here

What I'm trying to convey to you is that you should ignore bad
results that you get with no EV compensation and do your tests using
+.7 EV as otherwise you're essentially complaining about noise that
appears when the shot is underexposed. Just about any camera will
have noise problems with underexposures and by not compensating for
the inaccurate meter you are, in effect, underexposing.

Hey guys (and Sandy)!

Am I a part of some surrealistic dream or something

Under exposing 0.7 stops will not result in such bad images. Never - ever. Not even the worst kind of camera should do that.

I see only three possibilities

1. The camera is defective.

2. SD14s are cr@p.

3. Some kind of huge mistake is made somewhere.

BTW - saying that you have to over expose is the same thing as saying that the company that makes the cameras is not entirely honest with their ISO settings. But thats another story. And ... my Pentax has the same problem

--
Roland

miketuthill · Mar 13, 2008

Hi Roland,

Roland Karlsson said:
miketuthill said:

We seem to be talking around one another here

What I'm trying to convey to you is that you should ignore bad
results that you get with no EV compensation and do your tests using
+.7 EV as otherwise you're essentially complaining about noise that
appears when the shot is underexposed. Just about any camera will
have noise problems with underexposures and by not compensating for
the inaccurate meter you are, in effect, underexposing.

Click to expand...

Hey guys (and Sandy)!

Am I a part of some surrealistic dream or something

Under exposing 0.7 stops will not result in such bad images. Never -
ever. Not even the worst kind of camera should do that.

Depends on how you post process and the nature of the subject does it not? Plus, we're talking a foveon here so typical sensor characteristics don't apply

Roland Karlsson said:
BTW - saying that you have to over expose is the same thing as saying
that the company that makes the cameras is not entirely honest with
their ISO settings. But thats another story. And ... my Pentax has
the same problem

That's one way of looking at it

I think it's just a poorly calibrated meter myself (but I'm not a techie so that's just a guess on my part).

--
http://www.pbase.com/miketuthill

Ed_S · Mar 13, 2008

Roland Karlsson said:
miketuthill said:

We seem to be talking around one another here

What I'm trying to convey to you is that you should ignore bad
results that you get with no EV compensation and do your tests using
+.7 EV as otherwise you're essentially complaining about noise that
appears when the shot is underexposed. Just about any camera will
have noise problems with underexposures and by not compensating for
the inaccurate meter you are, in effect, underexposing.

Click to expand...

Hey guys (and Sandy)!

Am I a part of some surrealistic dream or something

Under exposing 0.7 stops will not result in such bad images. Never -
ever. Not even the worst kind of camera should do that.

I see only three possibilities

1. The camera is defective.

2. SD14s are cr@p.

3. Some kind of huge mistake with is made somewhere.

BTW - saying that you have to over expose is the same thing as saying
that the company that makes the cameras is not entirely honest with
their ISO settings. But thats another story. And ... my Pentax has
the same problem

--
Roland

Hi, Roland,

I 'm just headed out the door and hope I'm not butting in. I think the point which has been discussed in other threads over recent months is that particularly at higher ISOs, images exposed for average or highlights may exhibit objectionable noise in shadow regions. The prevailing philosophy among SD14 users has been to use +EV (0.7 for example) in shooting such scenes particularly at higher ISOs - in essence exposing for shadow vs. highlight, because the highlights have more headroom on the SD14. Whether that exhibits optimism on Sigma's part about the ISO rating I won't comment upon. I think this is particularly important in low light and low light where the illumination isn't full spectrum.

I think it's essentially the "expose to the right" philosophy referring to the histogram since many seem to experience that the highlights can be recovered if not pushed past the right end of the histogram.

Kind regards,
--
Ed_S
http://www.pbase.com/ecsquires

Roland Karlsson · Mar 13, 2008

miketuthill said:
Depends on how you post process and the nature of the subject does it
not? Plus, we're talking a foveon here so typical sensor
characteristics don't apply

hehe ... dont say that too loud. Because that really means that the camera is cr@p. And we dont want that do we?

miketuthill said:
I think it's just a poorly calibrated meter myself (but I'm not a
techie so that's just a guess on my part).

In this case it should a be a poorly calibrated shutter or poorly calibrated lens. He used the camera manually.

--
Roland

Roland Karlsson · Mar 13, 2008

Ed_S said:
Hi, Roland,

I 'm just headed out the door and hope I'm not butting in. I think
the point which has been discussed in other threads over recent
months is that particularly at higher ISOs, images exposed for
average or highlights may exhibit objectionable noise in shadow
regions. The prevailing philosophy among SD14 users has been to use
+EV (0.7 for example) in shooting such scenes particularly at higher
ISOs - in essence exposing for shadow vs. highlight, because the
highlights have more headroom on the SD14. Whether that exhibits
optimism on Sigma's part about the ISO rating I won't comment upon. I
think this is particularly important in low light and low light where
the illumination isn't full spectrum.

I think it's essentially the "expose to the right" philosophy
referring to the histogram since many seem to experience that the
highlights can be recovered if not pushed past the right end of the
histogram.

Yepp - and not a word in your reply says other than Sigma over stating their ISO values. Thats how the result should be if they did just that.

But ... thats hardly the problem here ... is it? I mean - the pictures that the OP showed was very bad.

--
Roland

miketuthill · Mar 13, 2008

Roland Karlsson said:
miketuthill said:

Depends on how you post process and the nature of the subject does it
not? Plus, we're talking a foveon here so typical sensor
characteristics don't apply

Click to expand...

hehe ... dont say that too loud. Because that really means that the
camera is cr@p. And we dont want that do we?

I prefer to characterize it as "different".

Roland Karlsson said:
Roland Karlsson said:

I think it's just a poorly calibrated meter myself (but I'm not a
techie so that's just a guess on my part).

Click to expand...

In this case it should a be a poorly calibrated shutter or poorly
calibrated lens. He used the camera manually.

Manual or not, he's still got to expose properly though doesn't he?

--
http://www.pbase.com/miketuthill

Dr. Riton · Mar 13, 2008

Roland Karlsson said:
Hey guys (and Sandy)!

Am I a part of some surrealistic dream or something
Under exposing 0.7 stops will not result in such bad images. Never -
ever. Not even the worst kind of camera should do that.

Totally agree.

In appearence, the noise alkonavt is displaying is totally out of bounds for a 14 at 100 ISO when SPP is set at 0.

However, one point i don't undersand in his description is "Using same levels correction in Adobe Photoshop. (Just expand levels 2-50)". This could be just anything.

Alko, why don't you just display the images fresh from SPP?

Ed_S · Mar 13, 2008

Roland - not quite out the door yet ;-)

Umm - again you can draw your own ISO rating conclusions. From what I saw though, especially shooting in very low light, I think we may be getting into the issue of chroma noise when the Foveon is underexposed. I think in most cases the middle tones to highlights will come out pretty well if exposed by the nominal ISO numbers. But noise may increase in shadows (i.e. underexposed) part of images, especially if exposed for the highlights or even the mid tones in high DR situations. May have to do with the Foveon imaging algorithms and the multi-layers. Of course I could be wrong - not the first time.

Regards,
--
Ed_S
http://www.pbase.com/ecsquires

Roland Karlsson · Mar 13, 2008

miketuthill said:
I prefer to characterize it as "different".

hehe - whatever ...

miketuthill said:
Manual or not, he's still got to expose properly though doesn't he?

Yes - of course. But - if the image gets that bad at 0.7 stops under exposure - then correctly exposed images should look very, very, very bad in the darker areas. Just an ordinary healthy looking grass lawn shall be at least one stop under exposed to get its normal exposure.

--
Roland

Roland Karlsson · Mar 13, 2008

Ed_S said:
Roland - not quite out the door yet ;-)

Hey - do you have the computer in the doorway

Ed_S said:
Umm - again you can draw your own ISO rating conclusions. From what I
saw though, especially shooting in very low light, I think we may be
getting into the issue of chroma noise when the Foveon is
underexposed. I think in most cases the middle tones to highlights
will come out pretty well if exposed by the nominal ISO numbers. But
noise may increase in shadows (i.e. underexposed) part of images,
especially if exposed for the highlights or even the mid tones in
high DR situations. May have to do with the Foveon imaging algorithms
and the multi-layers. Of course I could be wrong - not the first time.

Yes - thats the theory. And I agree with that theory.

What puzzles me though is how just a stop under exposure can destroy the entire image. Normally images have a dynamic range of several stops. Under exposure should just move the entire package of exposure values one atop down. Only the darkest parts should be affected by that.

--
Roland

miketuthill · Mar 13, 2008

Roland Karlsson said:
miketuthill said:

I prefer to characterize it as "different".

Click to expand...

hehe - whatever ...

Roland Karlsson said:

Manual or not, he's still got to expose properly though doesn't he?

Click to expand...

Yes - of course. But - if the image gets that bad at 0.7 stops under
exposure - then correctly exposed images should look very, very, very
bad in the darker areas. Just an ordinary healthy looking grass lawn
shall be at least one stop under exposed to get its normal exposure.

I suppose it's entirely possible that he does have a defective unit.

--
http://www.pbase.com/miketuthill

Guido FORRIER · Mar 13, 2008

ISO is never exact !
exposure is never correct !
When using the "zone system " you must:

use a spotmeter , decide how to expose , in many situations you must make a choice because the dynamic range of the scene is to big for de film/sensor

-calibrate your system with tests : there is no exact photometer , camera shutter and lens aperture .

the iso is graded by the cameramaker , not by you . YOU must make your own iso .

Because of all this variables and when i have not the time or the will i simply use bracketing and choose the shot with the best histogram .
Here again you can sse the importance of life view and life histogram !

OK you must do some work yourself with sigma : the camera is not thinking for you and is not as sophisticated as others .
Greetings,
Guido

Sigma sd14 noise at ISO-100

Senior Member

Active member

Senior Member

Active member

Senior Member

Senior Member

Active member

Senior Member

Forum Pro

Senior Member

Veteran Member

Forum Pro

Forum Pro

Senior Member

Forum Enthusiast

Veteran Member

Forum Pro

Forum Pro

Senior Member

Senior Member

Keyboard shortcuts