Pentax ist ds

nemrtvy said:

Yes, DS could be slower but did you manage to spot biggest
difference ? Viewfinder. This is for me by far the most important
thing on camera.

Click to expand...

Mark Ransom said:

Nikon uses a focusing motor in the lens. Pentax uses a motor in
the camera itself.

I have no experience with the Sigma to tell you if it's abnormally
slow or not. But I would try to compare a genuine Pentax lens.

tom boycott said:

Yes they were similar lenses. The Nikon had 18-70 lens and the
Pentax had 18-50.
Does the Nikon havea different methid of focusing?

Click to expand...

Click to expand...

Greg Lovern said:

There have been many threads and posts in this forum documenting
how some people get very slow focusing with certain Sigma lenses on
their D, while others have no problem at all with the very same
Sigma lenses, also on their D. If the problem is Sigma's rather
than Pentax's, it seems reasonable to guess that the DS might have
the same issue -- some people get slow focus, while others do not
with the same Sigma lens. Maybe the DS in the store, with the Sigma
lens on it, was experiencing the slow focus problem. Since there is
obviously some uncertainty, why not test with the Pentax 18-55 lens
on the Pentax instead of the Sigma.

Also, isn't auto-focusing faster through a sharper lens? The Nikon
18-70 sells separately for I think around 3 times what the Sigma
sells separately for. I think that makes the comparison about as
fair as putting expensive, high-performance tires on one sports
car, cheap tires on a similar sports car, and comparing the two
cars' performance. Oh, the one with the better tires performs
better? What a surprise.

Greg

Click to expand...

Greg Lovern said:

Also, isn't auto-focusing faster through a sharper lens? The Nikon
18-70 sells separately for I think around 3 times what the Sigma
sells separately for. I think that makes the comparison about as
fair as putting expensive, high-performance tires on one sports
car, cheap tires on a similar sports car, and comparing the two
cars' performance. Oh, the one with the better tires performs
better? What a surprise.

Greg

Mark Ransom said:

Nikon uses a focusing motor in the lens. Pentax uses a motor in
the camera itself.

I have no experience with the Sigma to tell you if it's abnormally
slow or not. But I would try to compare a genuine Pentax lens.

tom boycott said:

Yes they were similar lenses. The Nikon had 18-70 lens and the
Pentax had 18-50.
Does the Nikon havea different methid of focusing?

Click to expand...

Click to expand...

Click to expand...

tom boycott said:

It's all very confusing. I've been told that you get quicker
focusing if the lens has a motor in it as well as the camera.

Click to expand...

tom boycott said:

However, when I look at the Sigma web site
I see that the lenses offered with the Pentax all have the AF
prefix for example:
AF 18-125

Click to expand...

tom boycott said:

Re using a Pentax lens someone in this forum said that the Pentax
lenses are all made by Sigma?!

Click to expand...

tom boycott said:

This camera has just come into the stores here in Australlia and I
was very excited as I have several Pentax lenses. However when I
tried it in the shop it was very slow compared to the Nikon D70.

Click to expand...

tom boycott said:

I'm now thinking maybe a
Panasonic Z20 but I haven't checked that for speed.

Click to expand...

Brett St Pierre said:

tom boycott said:

This camera has just come into the stores here in Australlia and I
was very excited as I have several Pentax lenses. However when I
tried it in the shop it was very slow compared to the Nikon D70.

Click to expand...

Quiet frankly that's BS. I have a young boy and if you know
anything they NEVER stop moving. Lag is the least of my issues.

Click to expand...

Brett St Pierre said:

I have to say I am assuming the DS is as quick as my *istD which I
have compared back-to-back with the D70 and in normal shooting
there isn't much in it in terms of focus... Nikon fans tell me the
D70 is faster but I wouldn't put any money on it. What's 0.1 sec
compared to 0.98 sec? Of course you might be talking about low
light and then things slow down for all cameras

Click to expand...

Brett St Pierre said:

Shutter lag in both is cameras negligible.

More worrying is the D70s blown highlights and sometimes poor auto
white balance.

Brett St Pierre said:

I'm now thinking maybe a
Panasonic Z20 but I haven't checked that for speed.

Click to expand...

The FZ20 is reputed to be good and an intersting camera especially
with that F2.8 lens. If you are not really serious about the
benefits of a D/SLR then you should look at it.
Of course it has the small sensor noise issue that everything but a
DLSR has. Maximum ISO is 400 and by then noise is well and truly
present. All the DLSRs shoot up to ISO800 without noise issues and
higher in many cases.

--
Brett



The Journey is the Thing

Click to expand...

• Stronger moment arm to turn barrel -usually gives faster autofocus
• No gearing losses related to connecting motor to autofocus mechanism
• Can align motor properties with what is required by lens (i.e. bigger motor for lenses with large elements, smaller faster motors for small lenses)

• Cost - in effect, you have a different motor for each lens
• Compactness - not as bad as you'd think, but the motor adds to the weight and size of the lens.
• Issues with 3rd party lenses (although Pentax has also had troubles with some Sigma lenses, however the potential for problems is greater).

tom boycott said:

Greg Lovern said:

Also, isn't auto-focusing faster through a sharper lens? The Nikon
18-70 sells separately for I think around 3 times what the Sigma
sells separately for. I think that makes the comparison about as
fair as putting expensive, high-performance tires on one sports
car, cheap tires on a similar sports car, and comparing the two
cars' performance. Oh, the one with the better tires performs
better? What a surprise.

Gre

Mark Ransom said:

Nikon uses a focusing motor in the lens. Pentax uses a motor in
the camera itself.

I have no experience with the Sigma to tell you if it's abnormally
slow or not. But I would try to compare a genuine Pentax lens.

tom boycott said:

Yes they were similar lenses. The Nikon had 18-70 lens and the
Pentax had 18-50.
Does the Nikon havea different methid of focusing?

Click to expand...

Click to expand...

Click to expand...

Click to expand...

Mattie said:

I used a
Canon 300v with a USM lens (the in-lens motor) and thought the AF
was really fast, but it became clear after a little while that the
focus was actually a little slower than the *ist (note - film
version) I was comparing it against. I was caught out by the lack
of noise - you don't hear the 300v hunting, and it's not always
clear that it's doing so. The *ist was a lot, lot noiser in
comparison, but it was very quick and positive, more so in fact
than the 300v. This isn't really a fair comparison, the *ist is a
significant amount more expensive than the 300v, but it illustrates
my point well - in-lens motors aren't a guarantee of faster
autofocus, but they do have many advantages.

Matt

Click to expand...

Mattie said:

Hi Tom

Canon and Nikon have a system where the AF motor is located in the
lens, whereas Pentax locate theirs in the camera body. I believe
that there might be a dual system, where Canon/Nikon have motors in
the camera body but don't always use them? The Canon system is
called USM, not sure what the Nikon one is. The Pentax system
connects the motor via a small rotating pin that meshes with the
autofocus gearing mechanism in the lens. The advantages may be
broken down as follows (everyone, please feel free to amend/append
as you see fit):

In-lens motor strengths:

• Stronger moment arm to turn barrel -usually gives faster autofocus
• No gearing losses related to connecting motor to autofocus mechanism
• Can align motor properties with what is required by lens (i.e.

bigger motor for lenses with large elements, smaller faster motors
for small lenses)

In-lens motor disadvantages:

• Cost - in effect, you have a different motor for each lens
• Compactness - not as bad as you'd think, but the motor adds to

the weight and size of the lens.

• Issues with 3rd party lenses (although Pentax has also had

troubles with some Sigma lenses, however the potential for
problems is greater).

There are other issues, however I think these are the main ones.

And now to the 'made by Sigma' point.

The cheaper Pentax zoom is made by Sigma and branded Pentax, this
is actually quite common - a lot of zooms are made by Tamron, and
rebadged. This is simply a matter of economics, as Sigma may have
better facilities for making that type of lens. Some Sigma lenses
have been known to work poorly with Pentax cameras as the lens
electronics (yes, they have electronic chips in them!) are patented
and Sigma allegedly didn't pay the license and had to
estimate/reverse engineer the protocols. However, for the ones
Sigma make for Pentax I think Pentax actually insert the
electronics. A few people seem to think the Sigma lens is pretty
poor, and if you're really after a fair comparison it might be best
to get a Nikon-fit and Pentax-fit of an identical 3rd party lens
(Sigma, Tamron, Tokina) and try those out on the D70 and *istDs
respectively. I'd still expect the Nikon to be faster (they have
years of Pro level experience which has driven development of the
autofocus system, plus in-lens motors), but I would suggest there
wouldn't be much in it. The in-body motor system is much noisier
(good in-lens systems are almost silent), as there is gearing noise
and the in-lens motors are piezo-electric (don't worry, not
important) which are a lot quieter than standard electric motors.
This can cause some confusion regarding focus speed. I used a
Canon 300v with a USM lens (the in-lens motor) and thought the AF
was really fast, but it became clear after a little while that the
focus was actually a little slower than the *ist (note - film
version) I was comparing it against. I was caught out by the lack
of noise - you don't hear the 300v hunting, and it's not always
clear that it's doing so. The *ist was a lot, lot noiser in
comparison, but it was very quick and positive, more so in fact
than the 300v. This isn't really a fair comparison, the *ist is a
significant amount more expensive than the 300v, but it illustrates
my point well - in-lens motors aren't a guarantee of faster
autofocus, but they do have many advantages.

Matt

Click to expand...

Lance B said:

Tom,

I just tried firing off a few random shots around home with my *ist
D to test out the shutter lag time and focusing speed.
In fairly normal light conditions, ie outside about an hour before
dusk with cloud cover, or a fairly normally lit room, the shutter
fires instantly the button is pressed. I mean INSTANTLY. There is
no shutter lag. The only thing that holds it up focus, ie if it is
shooting into a darkish area with little contrast that makes it
difficult for the camera to focus or any camera for that matter.
In any situation where there are normal light levels the camera
focuses extremely quickly and basically fires instantaneously.
If you have had experienced that the DS is slower to react to the
shutter being depressed it maybe in these low light situations as
it tries to focus in low contrast. This will make it difficult for
any camera, but the D70 maybe a little better in this regard and
thus will fire the shutter sooner. I will say that I think the D or
DS will fire just as quickly as the D70 in normal light situations
as how much quicker than instantaneous do you want?

--
Lance*istD

Click to expand...

Lance B said:

Tom,

I just tried firing off a few random shots around home with my *ist
D to test out the shutter lag time and focusing speed.
In fairly normal light conditions, ie outside about an hour before
dusk with cloud cover, or a fairly normally lit room, the shutter
fires instantly the button is pressed. I mean INSTANTLY. There is
no shutter lag. The only thing that holds it up focus, ie if it is
shooting into a darkish area with little contrast that makes it
difficult for the camera to focus or any camera for that matter.
In any situation where there are normal light levels the camera
focuses extremely quickly and basically fires instantaneously.
If you have had experienced that the DS is slower to react to the
shutter being depressed it maybe in these low light situations as
it tries to focus in low contrast. This will make it difficult for
any camera, but the D70 maybe a little better in this regard and
thus will fire the shutter sooner. I will say that I think the D or
DS will fire just as quickly as the D70 in normal light situations
as how much quicker than instantaneous do you want?

--
Lance*istD

Click to expand...

Brett St Pierre said:

tom boycott said:

This camera has just come into the stores here in Australlia and I
was very excited as I have several Pentax lenses. However when I
tried it in the shop it was very slow compared to the Nikon D70.

Click to expand...

Quiet frankly that's BS. I have a young boy and if you know
anything they NEVER stop moving. Lag is the least of my issues.

I have to say I am assuming the DS is as quick as my *istD which I
have compared back-to-back with the D70 and in normal shooting
there isn't much in it in terms of focus... Nikon fans tell me the
D70 is faster but I wouldn't put any money on it. What's 0.1 sec
compared to 0.98 sec? Of course you might be talking about low
light and then things slow down for all cameras

Shutter lag in both is cameras negligible.

More worrying is the D70s blown highlights and sometimes poor auto
white balance.

Brett St Pierre said:

I'm now thinking maybe a
Panasonic Z20 but I haven't checked that for speed.

Click to expand...

The FZ20 is reputed to be good and an intersting camera especially
with that F2.8 lens. If you are not really serious about the
benefits of a D/SLR then you should look at it.
Of course it has the small sensor noise issue that everything but a
DLSR has. Maximum ISO is 400 and by then noise is well and truly
present. All the DLSRs shoot up to ISO800 without noise issues and
higher in many cases.

--
Brett



The Journey is the Thing

Click to expand...

Mattie said:

Hi Tom

Canon and Nikon have a system where the AF motor is located in the
lens, whereas Pentax locate theirs in the camera body. I believe
that there might be a dual system, where Canon/Nikon have motors in
the camera body but don't always use them? The Canon system is
called USM, not sure what the Nikon one is. The Pentax system
connects the motor via a small rotating pin that meshes with the
autofocus gearing mechanism in the lens. The advantages may be
broken down as follows (everyone, please feel free to amend/append
as you see fit):

In-lens motor strengths:

• Stronger moment arm to turn barrel -usually gives faster autofocus
• No gearing losses related to connecting motor to autofocus mechanism
• Can align motor properties with what is required by lens (i.e.

bigger motor for lenses with large elements, smaller faster motors
for small lenses)

In-lens motor disadvantages:

• Cost - in effect, you have a different motor for each lens
• Compactness - not as bad as you'd think, but the motor adds to

the weight and size of the lens.

• Issues with 3rd party lenses (although Pentax has also had

troubles with some Sigma lenses, however the potential for
problems is greater).

There are other issues, however I think these are the main ones.

And now to the 'made by Sigma' point.

The cheaper Pentax zoom is made by Sigma and branded Pentax, this
is actually quite common - a lot of zooms are made by Tamron, and
rebadged. This is simply a matter of economics, as Sigma may have
better facilities for making that type of lens. Some Sigma lenses
have been known to work poorly with Pentax cameras as the lens
electronics (yes, they have electronic chips in them!) are patented
and Sigma allegedly didn't pay the license and had to
estimate/reverse engineer the protocols. However, for the ones
Sigma make for Pentax I think Pentax actually insert the
electronics. A few people seem to think the Sigma lens is pretty
poor, and if you're really after a fair comparison it might be best
to get a Nikon-fit and Pentax-fit of an identical 3rd party lens
(Sigma, Tamron, Tokina) and try those out on the D70 and *istDs
respectively. I'd still expect the Nikon to be faster (they have
years of Pro level experience which has driven development of the
autofocus system, plus in-lens motors), but I would suggest there
wouldn't be much in it. The in-body motor system is much noisier
(good in-lens systems are almost silent), as there is gearing noise
and the in-lens motors are piezo-electric (don't worry, not
important) which are a lot quieter than standard electric motors.
This can cause some confusion regarding focus speed. I used a
Canon 300v with a USM lens (the in-lens motor) and thought the AF
was really fast, but it became clear after a little while that the
focus was actually a little slower than the *ist (note - film
version) I was comparing it against. I was caught out by the lack
of noise - you don't hear the 300v hunting, and it's not always
clear that it's doing so. The *ist was a lot, lot noiser in
comparison, but it was very quick and positive, more so in fact
than the 300v. This isn't really a fair comparison, the *ist is a
significant amount more expensive than the 300v, but it illustrates
my point well - in-lens motors aren't a guarantee of faster
autofocus, but they do have many advantages.

Matt

Click to expand...

Mark Ransom said:

Easy one first: USM is only a designation for SOME of the Canon
lenses. I think it stands for Ultra Sonic Motor. These motors are
fast and quiet, which is why you find it on all their most
expensive lenses. The cheap lenses all use a different type of
motor, including the kit lens.

I've heard that Nikon is the one with the dual system, although I
haven't seen this from any authoritative source; I've just never
been interested in verifying this factoid.

Click to expand...

Mark Ransom said:

Finally, I've NEVER heard of a Pentax lens that was actually
manufactured by Sigma. If you can back up this claim, please do.
Some confusion may be generated by the fact that the Australian
importer has chosen to create a "kit" that includes the Sigma lens

• as far as I know, this is the only country where that is the case.

Mattie said:

Hi Tom

Canon and Nikon have a system where the AF motor is located in the
lens, whereas Pentax locate theirs in the camera body. I believe
that there might be a dual system, where Canon/Nikon have motors in
the camera body but don't always use them? The Canon system is
called USM, not sure what the Nikon one is. The Pentax system
connects the motor via a small rotating pin that meshes with the
autofocus gearing mechanism in the lens. The advantages may be
broken down as follows (everyone, please feel free to amend/append
as you see fit):

In-lens motor strengths:

• Stronger moment arm to turn barrel -usually gives faster autofocus
• No gearing losses related to connecting motor to autofocus mechanism
• Can align motor properties with what is required by lens (i.e.

bigger motor for lenses with large elements, smaller faster motors
for small lenses)

In-lens motor disadvantages:

• Cost - in effect, you have a different motor for each lens
• Compactness - not as bad as you'd think, but the motor adds to

the weight and size of the lens.

• Issues with 3rd party lenses (although Pentax has also had

troubles with some Sigma lenses, however the potential for
problems is greater).

There are other issues, however I think these are the main ones.

And now to the 'made by Sigma' point.

The cheaper Pentax zoom is made by Sigma and branded Pentax, this
is actually quite common - a lot of zooms are made by Tamron, and
rebadged. This is simply a matter of economics, as Sigma may have
better facilities for making that type of lens. Some Sigma lenses
have been known to work poorly with Pentax cameras as the lens
electronics (yes, they have electronic chips in them!) are patented
and Sigma allegedly didn't pay the license and had to
estimate/reverse engineer the protocols. However, for the ones
Sigma make for Pentax I think Pentax actually insert the
electronics. A few people seem to think the Sigma lens is pretty
poor, and if you're really after a fair comparison it might be best
to get a Nikon-fit and Pentax-fit of an identical 3rd party lens
(Sigma, Tamron, Tokina) and try those out on the D70 and *istDs
respectively. I'd still expect the Nikon to be faster (they have
years of Pro level experience which has driven development of the
autofocus system, plus in-lens motors), but I would suggest there
wouldn't be much in it. The in-body motor system is much noisier
(good in-lens systems are almost silent), as there is gearing noise
and the in-lens motors are piezo-electric (don't worry, not
important) which are a lot quieter than standard electric motors.
This can cause some confusion regarding focus speed. I used a
Canon 300v with a USM lens (the in-lens motor) and thought the AF
was really fast, but it became clear after a little while that the
focus was actually a little slower than the *ist (note - film
version) I was comparing it against. I was caught out by the lack
of noise - you don't hear the 300v hunting, and it's not always
clear that it's doing so. The *ist was a lot, lot noiser in
comparison, but it was very quick and positive, more so in fact
than the 300v. This isn't really a fair comparison, the *ist is a
significant amount more expensive than the 300v, but it illustrates
my point well - in-lens motors aren't a guarantee of faster
autofocus, but they do have many advantages.

Matt

Click to expand...

Click to expand...

tom boycott said:

I don't mind paying more it's just that I have so many Pentax
lenses already. If someone wants to buy them off me I'd be quite
happy to get a Nikon D70.
It's all very confusing. I've been told that you get quicker
focusing if the lens has a motor in it as well as the camera. When
I asked the shop how you would know if it has a motor or not , I
was told that the AF in front of the focal length determines that
there is a motor in it. However, when I look at the Sigma web site
I see that the lenses offered with the Pentax all have the AF
prefix for example:
AF 18-125
Re using a Pentax lens someone in this forum said that the Pentax
lenses are all made by Sigma?!

Click to expand...

Lance B said:

Tom,

I just tried firing off a few random shots around home with my *ist
D to test out the shutter lag time and focusing speed.
In fairly normal light conditions, ie outside about an hour before
dusk with cloud cover, or a fairly normally lit room, the shutter
fires instantly the button is pressed. I mean INSTANTLY. There is
no shutter lag. The only thing that holds it up focus, ie if it is
shooting into a darkish area with little contrast that makes it
difficult for the camera to focus or any camera for that matter.
In any situation where there are normal light levels the camera
focuses extremely quickly and basically fires instantaneously.
If you have had experienced that the DS is slower to react to the
shutter being depressed it maybe in these low light situations as
it tries to focus in low contrast. This will make it difficult for
any camera, but the D70 maybe a little better in this regard and
thus will fire the shutter sooner. I will say that I think the D or
DS will fire just as quickly as the D70 in normal light situations
as how much quicker than instantaneous do you want?

--
Lance*istD

Click to expand...

tom boycott said:

Hi Brett,
Thanks for that. I assume you mean 0.098 when you say "What's 0.1 sec
compared to 0.98 sec? "
I know I sound incredibly ignorant but when you talk about noise
when comparing a DSLR with the Z20 - how does that manifest itself?
I'm assuming that in low light it means you get the digital
eqivalent of graininess? Is that correct.
The Z20 appeals to me in that there is a lot less to carry around
if you do a lot of travelling which I do. What other disadvantages
would it haveand is there anything intrinsically about the Z20
which would make it slower than a DSLR?
Noone has stock of it in Australia yet so I still have not had a
chance to try it.
Tom

Click to expand...