a dslr question

[crystal]

I got a *istDL with the kit lens. I have very little experience with photography so I mostly used its autofocus to take the pictures. What I found is sometime the auto focus took too long to focus and I lost the moment. I wonder if a better lenses will have better response time?

thx.

 

[yhelothar]

I think the problem lies in the fact that the *ist DL isn't too hot in low light autofocus. In fact, non of the budget DSLRs are, and they all tend to hunt a lot.

 

[alphatarget1]

what were you trying to shoot?

 

[GTaudiophile]

In my experience, it's more of a lens factor. I bought a Sigma 30 F1.4 and it would hunt for ages in low light. My Tamron 28-75 F2.8 is better but still can be slow. But my $1250 24-105 F4L IS lens is like a laser. Push the trigger half way and it snaps and focuses where I need it to in one second. Nothing beats Canon's USM, no matter how many third parties try to copy.

 

[crystal]

Originally posted by: alphatarget1
what were you trying to shoot?

Just my kid as she crawls around. Most of the time, she looks elsewhere, but once she in a while she looks up the camera still tries to focus. As for the light, pretty normal household light. Yesterday I tested out the k100 at Frys, it seems to focus really fast. I don't know if it was the light they got in there or the lens. I didn't paid attention to what they got on for the demo. BTW, what lenses are good for general purpose shoots? Are the kits lenses ok? thx

 

[foghorn67]

Originally posted by: crystal

Originally posted by: alphatarget1
what were you trying to shoot?

Just my kid as she crawls around. Most of the time, she looks elsewhere, but once she in a while she looks up the camera still tries to focus. As for the light, pretty normal household light. Yesterday I tested out the k100 at Frys, it seems to focus really fast. I don't know if it was the light they got in there or the lens. I didn't paid attention to what they got on for the demo. BTW, what lenses are good for general purpose shoots? Are the kits lenses ok? thx

It's a combination. There are fast lenses and fast bodies. Lenses I would say make the most difference.
It's a shame that Sigma does not have a walkaround lens (general lens) that has HSM.
I think Pentax has a few lenses with the supersonic AF motors out early next year.

 

[kami333]

It's a combination of both, the body will set upper limit of the AF (AF motor, sensor, algorithm, etc) and the lens will most likely how fast it will implement it. The DL is the slowest in the *ist family, the new K100 and K10D and etc are supposed to have AF speeds faster than the original *ist D.

You have the 18-55 kit lens? It's a very decent lens, good coverage and quality especially for the price. You could get the 16-45 F4, it has AF than the 18-55 from my experience but not sure if it'll make a difference on the DL (I used to have it, not really a fan of it any more because of the size).

 

[jamesbond007]

Originally posted by: GTaudiophile
In my experience, it's more of a lens factor. I bought a Sigma 30 F1.4 and it would hunt for ages in low light. My Tamron 28-75 F2.8 is better but still can be slow. But my $1250 24-105 F4L IS lens is like a laser. Push the trigger half way and it snaps and focuses where I need it to in one second. Nothing beats Canon's USM, no matter how many third parties try to copy.

Couldn't agree more! I also have the same Tamron, but I have the 135 f/2L and that thing focuses like lightning on steroids!

However, there is some body factor into it. My 300D shows its age when areas are very dark, but the lens choice makes a world of difference.

 

[yhelothar]

Originally posted by: jamesbond007

Originally posted by: GTaudiophile
In my experience, it's more of a lens factor. I bought a Sigma 30 F1.4 and it would hunt for ages in low light. My Tamron 28-75 F2.8 is better but still can be slow. But my $1250 24-105 F4L IS lens is like a laser. Push the trigger half way and it snaps and focuses where I need it to in one second. Nothing beats Canon's USM, no matter how many third parties try to copy.

Couldn't agree more! I also have the same Tamron, but I have the 135 f/2L and that thing focuses like lightning on steroids!

However, there is some body factor into it. My 300D shows its age when areas are very dark, but the lens choice makes a world of difference.

It has some to do with the lens, but there's no much difference for pentax cameras when there are no in-lens focusing motors like canon's USM.

For the situations described by the OP, I'd just get myself a good high quality manual focus prime.