NOISE

[Paul]

Archived from groups: rec.photo.digital (More info?)

Stacey wrote:

> paul wrote:
>
>
>>Stacey wrote:
>>
>>
>>>paul wrote:
>>>
>>>
>>>>Here's a nice noisy detail with & without noise reduction, RAW & jpeg:
>>>>
>>>
> <http/www.edgehill.net/1/?SC=go.php&DIR=Misc/photography/raw-vs-jpg&PG=1&PIC=3>
>
>>>
>>>?? How can you "like" either of these blown to 400% images?
>>
>>
>>"Nice" as in "plenty visible for the sake of discussion".
>>
>>That was shot in low ISO but low light and exaggerated with curves in
>>PS. 400% so that it is not a subjective squinty confusion but very clear
>>exactly what the noise looks like.
>
>
> So what do the different ones look like at normal viewing like downsampled
> to viewable size or upsampled for printing? If you can't see it there, who
> cares?

Here's D70 noise at ISO 1600 reduced for web and still very visible:
<http/www.edgehill.net/1/?SC=go.php&DIR=California/Bay-Area/Santa-Cruz/2005-01-26&PG=4&PIC=19>
I guess I need a faster lens 'cause I'm constantly struggling to capture
low light images.

 

[Paul]

Archived from groups: rec.photo.digital (More info?)

Stacey wrote:
>
> paul wrote:
>
>>I played with the neatimage trial and liked what I saw
>
> Again you need the retail + version that works as a PS plugin to really use
> it this way. It's no harder to use than applying sharpen filter etc.


Yes, I think it should be a good tool to have.



>
>>How would it help to downsample in steps, I never
>>heard of that?
>>
>
>
> Yes, a single step upsample or downsample is bad, see the jaggies on the
> angled stem? That's from a single downsample. It also kills details in a
> wide angle landscape etc. I've started using Qimage for resampling, it has
> a "pyramid" resampling alogrithm that avoids needed to resample in 5-10%
> steps. Also is amazing how much it improves the sharpness in prints.
> Otherwise you need to do resampling in 10% at max steps.


Hmm, I never heard this. I'll take a look at qimage.



>>
>>>You don't need faster lenses, although it wouldn't hurt I suppose if you
>>>can stand less DOF.
>>
>>
>>My limited understanding is that a faster lens will let me use a faster
>>speed at any f-stop, basically like boosting the ISO across the board.
>
>
> Yes but at a price, shallower DOF which for macro shots and landsacpes can
> be a problem.



My understanding is that I could shoot at f/8 or 11 in low light with a
fast lens.


>>
>>Yes it's probably underexposed like that whole day's shooting which was
>>a disaster and a learning experience. In this case I might have
>>underexposed simply to get a fast enough shutter speed to avoid motion
>>blur. It was the only option (besides a tripod or image stablized lens).
>
>
> You really have to get past this -not using a tripod- if you want to make
> good photographs of subjects like this. If not, you'll always just get
> mediocre results no matter how much you spend on gear.


Well, patience in the field isn't my strong point, that would be more
like inquisitiveness. I do have patience to sort through a billion pics
later though. We each have our personal approaches. I'm pretty sure with
a fast image stabilized lens I'd be able to do a lot more of what I like
to do with better results.

 

[Stacey]

Archived from groups: rec.photo.digital (More info?)

paul wrote:

>>
>> Yes but at a price, shallower DOF which for macro shots and landsacpes
>> can be a problem.
>
>
>
> My understanding is that I could shoot at f/8 or 11 in low light with a
> fast lens.


You should be able to do this with a slow lens as well unless it is a poor
quality one. F8 is F8 no matter if the lens is a F5.6 max lens or a f2.8
max lens.


>>
>> You really have to get past this -not using a tripod- if you want to make
>> good photographs of subjects like this. If not, you'll always just get
>> mediocre results no matter how much you spend on gear.
>
>
> Well, patience in the field isn't my strong point,

Might try working on that?

> I do have patience to sort through a billion pics
> later though.

That sound awful!

--

Stacey

 

[Paul]

Archived from groups: rec.photo.digital (More info?)

Stacey wrote:
> paul wrote:
>
>
>>>Yes but at a price, shallower DOF which for macro shots and landsacpes
>>>can be a problem.
>>
>>
>>
>>My understanding is that I could shoot at f/8 or 11 in low light with a
>>fast lens.
>
>
>
> You should be able to do this with a slow lens as well unless it is a poor
> quality one. F8 is F8 no matter if the lens is a F5.6 max lens or a f2.8
> max lens.


Am I understanding this wrong? A fast lens should shoot at a faster
speed at the same f-stop as a slow lens as I understand. It's not just
that it's capable of going to a lower f-stop number. Please clarify if
I'm mistaken.


>
>>>You really have to get past this -not using a tripod- if you want to make
>>>good photographs of subjects like this. If not, you'll always just get
>>>mediocre results no matter how much you spend on gear.
>>
>>
>>Well, patience in the field isn't my strong point,
>
>
> Might try working on that?
>
>
>> I do have patience to sort through a billion pics
>>later though.
>
>
> That sound awful!


Well, we all have our personalities. For me spending time in the field
fiddling with a tripod would drive me nuts, once I settle down on the
computer in the evening, I have no problem with patience.

 

[Guest]

Archived from groups: rec.photo.digital (More info?)

paul wrote:


> Am I understanding this wrong? A fast lens should shoot at a faster
> speed at the same f-stop as a slow lens as I understand. It's not
just
> that it's capable of going to a lower f-stop number. Please clarify
if
> I'm mistaken.
>

The only thing that makes a fast lens a fast lens is that it can go to
a lower f number. Lower f number = more light = faster shutter speed =
less motion blur

 

[Guest]

Archived from groups: rec.photo.digital (More info?)

On 17 Feb 2005 09:51:39 -0800, "Scott W" <biphoto@hotmail.com> wrote:

>
>paul wrote:
>
>> Am I understanding this wrong? A fast lens should shoot at a faster
>> speed at the same f-stop as a slow lens as I understand. It's not
>just
>> that it's capable of going to a lower f-stop number. Please clarify
>if
>> I'm mistaken.
>>
>
>The only thing that makes a fast lens a fast lens is that it can go to
>a lower f number. Lower f number = more light = faster shutter speed =
>less motion blur

...and less DOF, which isn't always useful.

Noise is purely a factor of ISO & shutter duration, so a faster lens
only helps when it's being used wide open (wider than a slow lens is
capable of), which artistically, may not be the best choice.

There's no such thing as a free lunch.

--
Owamanga!

 

[Paul]

Archived from groups: rec.photo.digital (More info?)

Owamanga wrote:
> On 17 Feb 2005 09:51:39 -0800, "Scott W" <biphoto@hotmail.com> wrote:
>
>
>>paul wrote:
>>
>>
>>>Am I understanding this wrong? A fast lens should shoot at a faster
>>>speed at the same f-stop as a slow lens as I understand. It's not
>>
>>just
>>
>>>that it's capable of going to a lower f-stop number. Please clarify
>>
>>if
>>
>>>I'm mistaken.
>>>
>>
>>The only thing that makes a fast lens a fast lens is that it can go to
>>a lower f number. Lower f number = more light = faster shutter speed =
>>less motion blur
>
>
> ..and less DOF, which isn't always useful.
>
> Noise is purely a factor of ISO & shutter duration, so a faster lens
> only helps when it's being used wide open (wider than a slow lens is
> capable of), which artistically, may not be the best choice.
>
> There's no such thing as a free lunch.


OK thanks guys, I understood wrong then.

 

[Guest]

Archived from groups: rec.photo.digital (More info?)

In message <WuSdnd379KJhWYnfRVn-ow@speakeasy.net>,
paul <paul@not.net> wrote:

>Am I understanding this wrong? A fast lens should shoot at a faster
>speed at the same f-stop as a slow lens as I understand. It's not just
>that it's capable of going to a lower f-stop number. Please clarify if
>I'm mistaken.

The term "fast lens", as I understand it, derives from the fact that all
other things being equal, a lens with a larger aperture (lower f-stop)
will allow a faster shutter speed, but only at that aperture.
--

<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><

 

[Guest]

Archived from groups: rec.photo.digital (More info?)

In message <vvm9115p5k8n52uplbp9ub0qecegg99923@4ax.com>,
Owamanga <nomail@hotmail.com> wrote:

>Noise is purely a factor of ISO & shutter duration,

Technically, this is true, but a lower f-stop may increase the
signal-to-noise ratio, and a larger one may increase it, at any given
ISO and shutter speed.
--

<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><

 

[Confused]

Archived from groups: rec.photo.digital (More info?)

On Thu, 17 Feb 2005 08:23:23 -0800
In message <WuSdnd379KJhWYnfRVn-ow@speakeasy.net>
paul <paul@not.net> wrote:

> Stacey wrote:
> > paul wrote:
> >
> >>> Yes but at a price, shallower DOF which for macro shots
> >>> and landsacpes can be a problem.

Landscapes much less of a DOF problem than macros.
If you get in the habit of pre-focusing then most
marginal DOF focus problems go away. Also, the
trick of auto-focusing on an object in the middle
of the focus target field and switching to manual
works well with me.

One of the more useful links that have been posted here.
http/www.dofmaster.com/dofjs.html

(heh...even old pharts new to all this learn once in a while...)

> >>> <snip "fast lens" part... already answered>

> >>> <snip lead-in to tripod discussion>
> >>
> >> I do have patience to sort through a billion pics
> >> later though.
> >
> > That sounds awful!

Indeed.

> Well, we all have our personalities. For me spending time in the field
> fiddling with a tripod would drive me nuts, once I settle down on the
> computer in the evening, I have no problem with patience.

Try a compromise, and don't settle for a cheaper smaller head, or a
non-rotating lock monopod. Find and try a Gitzo mono pod with a
NOVOFLEX CLASSICBALL 5 BallHead. It will serve as an "almost" tripod,
won't slow you down, can be used without touching the ground (it acts
like a stabilizer) and will actually save you time composing shots.
If you find a better, smoother, easier to use and more functional ball
head let me know... and do NOT settle for a small jerky light weight
head.

(there are a couple other heads in this class, but it's the only one I
could get my hands on. gonna get one for my gitzo explorer tripod,
too, so I can keep them tightly and permanently mounted. don't forget
quality quick releases and spare camera/lens side adaptors. ;^)

Jeff

 

[Stacey]

Archived from groups: rec.photo.digital (More info?)

paul wrote:

> Stacey wrote:

>>
>> You should be able to do this with a slow lens as well unless it is a
>> poor quality one. F8 is F8 no matter if the lens is a F5.6 max lens or a
>> f2.8 max lens.
>
>
> Am I understanding this wrong?

Yes you are!

> A fast lens should shoot at a faster
> speed at the same f-stop

Nope, same f stop need the same shutter speed no matter what lens is being
used.. Doesn't matter what lens or format. F8 at 1/60 is the same on a tiny
sensor digicam or an 8X10 film camera.

> as a slow lens as I understand. It's not just
> that it's capable of going to a lower f-stop number.

That's ALL the difference, to get the faster shutter speed, you have to use
the larger lens opening.

--

Stacey

 

[Paul]

Archived from groups: rec.photo.digital (More info?)

Confused wrote:
> On Thu, 17 Feb 2005 08:23:23 -0800
> In message <WuSdnd379KJhWYnfRVn-ow@speakeasy.net>
> paul <paul@not.net> wrote:
>
>>>>><snip>
>>>>
>>>>I do have patience to sort through a billion pics
>>>>later though.
>>>
>>>That sounds awful!
>
>
> Indeed.


I'm usually doing documentation, not strictly looking for art photos so
yes I want a lot of pictures. Obviously I don't want to sort a lot of
rejects.


>
>>Well, we all have our personalities. For me spending time in the field
>>fiddling with a tripod would drive me nuts, once I settle down on the
>>computer in the evening, I have no problem with patience.
>
>
> Try a compromise, and don't settle for a cheaper smaller head, or a
> non-rotating lock monopod. Find and try a Gitzo mono pod with a
> NOVOFLEX CLASSICBALL 5 BallHead.


Wow, that alone is $500. I'd rather pay for an Image Stabilized lens.


> It will serve as an "almost" tripod,
> won't slow you down, can be used without touching the ground (it acts
> like a stabilizer)


Hmm, that makes sense, just the weight & bulk would stabilize things
considerably hand held.


> and will actually save you time composing shots.
> If you find a better, smoother, easier to use and more functional ball
> head let me know... and do NOT settle for a small jerky light weight
> head.
>
> (there are a couple other heads in this class, but it's the only one I
> could get my hands on. gonna get one for my gitzo explorer tripod,
> too, so I can keep them tightly and permanently mounted. don't forget
> quality quick releases and spare camera/lens side adaptors. ;^)
>
> Jeff

 

[Paul]

Archived from groups: rec.photo.digital (More info?)

Stacey wrote:

> paul wrote:
>
>
>>Stacey wrote:
>
>
>>>You should be able to do this with a slow lens as well unless it is a
>>>poor quality one. F8 is F8 no matter if the lens is a F5.6 max lens or a
>>>f2.8 max lens.
>>
>>
>>Am I understanding this wrong?
>
>
> Yes you are!


Better late than never. I had photography 101 in college 20 years ago
<grin>.


>
>
>>A fast lens should shoot at a faster
>>speed at the same f-stop
>
>
> Nope, same f stop need the same shutter speed no matter what lens is being
> used.. Doesn't matter what lens or format. F8 at 1/60 is the same on a tiny
> sensor digicam or an 8X10 film camera.
>
>
>>as a slow lens as I understand. It's not just
>>that it's capable of going to a lower f-stop number.
>
>
> That's ALL the difference, to get the faster shutter speed, you have to use
> the larger lens opening.


Hmm, so any lens at f/8 will need the same shutter speed under the same
lighting conditions. A 'Fast' would necessarily have to be wider, larger
I guess, and probably longer?

http/www.armguard.com/security%20terms%20glossary.htm
" A term used to describe the speed of a lens, or its ability to pass
light through its lensing and onto the imager. It is determined by
dividing the focal length of the lens by the diameter."