[highyellow1]

All,
I'm loooing for some thoughts on the combos listed above based on AF speed and image quality. Not trying to start a brand war, just good opinions.

I think the image quality is a wash wrt just the cameras but obviously once you stick another lens on there then there is another factor added to the equation.

I really want to get deeper into motorcycle roadracing photography this summer. I'd also like to stay w/ Pentax K5 as I like the small size, ergos, and most of what they offered lens wise would meet my novice needs.

My major concern is AF! Is there much difference between the these combos (if I can find a 100-300 f4, if not I will probably go 150-500 if I stay pentax) and how much do you think AF will matter? AF shouldn't matter much in panning, right? Entering in/out of corners depending on where I'm located could have the bike coming at/away from me.

I have a K10D and have some ok shots but think AF has held me back and I also would like a further reaching lens. So the plan is to upgrade in the next month and hit the track.

As far as switching systems, I only have the the two kit lens, FA 50 F1.4, DA 21 and 360 flash. My other interests is getting into strobist, basketball (probably strobed) and just general shooting on vacation.

Thanks for your thoughts/opinions.

[jstevewhite]

I've not used a Nikon in years. Everyone says they have excellent AF. The 100-300 f4 isn't HSM on pentax, I think. From what I've read, the 70-300VR isn't the lens (IQ) the Sigma 100-300 F4 is, but it's not meant to be. So on the one hand you've got af speed (from what I read), and the other you've got IQ. Hard decision to make.

AF speed shouldn't matter a lot in lateral panning. I've read that all systems have trouble with objects approaching or receding rapidly, but your best bet is to, say, rent the camera and try it.

I know that many people use the utility x-300 zooms frequently for motorsports - I see 'em all over pixel-peeper.com.

[Babbs]

After Buying the K-5 and 16-50 star lens i loved it. but unfortunetly i quickly realized how slow it focuses in low light when my sister-in-law handed me her rebel. It focused instantly while the k-5 was searching.

K-5 take fantastic pictures in low light but the focusing is way to slow.

[Eruditass]

After Buying the K-5 and 16-50 star lens i loved it. but unfortunetly i quickly realized how slow it focuses in low light when my sister-in-law handed me her rebel. It focused instantly while the k-5 was searching.

K-5 take fantastic pictures in low light but the focusing is way to slow.

Ouch, that's just embarrassing.

One reason why I'm returning my K-5 and waiting for the next one.

[Babbs]

Ouch, that's just embarrassing.

One reason why I'm returning my K-5 and waiting for the next one.

I then realized that Pentax is not even in the same class as entry level Nikons and Canons for focusing.

You are right. It was embarrasing. I didn't mention anything beucase I thought I had this great camera setup.

Now I still believe I have the best camera on the market today but Pentax, FIX YOUR FOCUS SPEED!

[alexeyga]

Not exactly a fair comparison... 70-300VR is a great lens, however its rather weak IQ-wise between 200-300mm... well... relatively weak... But Sigma 100-300/4, is considerably better...

But if I had to choose Siggy 100-300/4 + K5 VS Siggy 100-300/4 + D7000, I'd go with the D7000 hands down...

Having just gone the K5==>D7000 road... again... I won't comment on IQ, but when it comes to AF, these are still worlds apart... K5's AF, although comparable in speed to Nikon, proved to be very unreliable in terms of accuracy... On the other hand, D7000 basically has the D300's AF module with some rounded corners... which is still the fastest-focusing cropped sensor body on the market... yeah-yeah... 7D is fast as well....

You should also consider the fact that K5 has a 24-RAW images worth of buffer space as oppose to D7000's 11 frames only... for some types of photography that might be a limitation...

As a side note, last week i've picked up a used Nikon 300/4 AF ED for half of what I was considering to pay for the Pentax A 300/4 a few weeks back.... it's not even funny...

[opiedog]

i have this combo and i love it. i don't have the siggy 100-300 f4 so can't compare, but this combo is great.

the tamron's VC is excellent, the AF is fast definitely faster than my kx w/ sigma 50-150 (HSM II).
on top of that, it's more accurate than my kx/50-150 combo ever was.

also remember that there are quite a bit more AF modes/adjustments on the D7k vs the k5, allowing your to pick the best mode for the scene.

i've posted in 2 different threads some 300mm wide open shots.



https://www.pentaxforums.com/forums/non-pentax-cameras-canon-nikon-etc/141336...r-raleigh.html

https://www.pentaxforums.com/forums/non-pentax-cameras-canon-nikon-etc/139570...harp-soft.html

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Last edited by opiedog; 04-26-2011 at 05:54 PM.

[highyellow1]

All, thanks for the input.

So I guess the question is really:
1. How much will AF speed matter in shooting motorcycle racing?
2. If I went Nikon, which lens would you recommend for this type of shooting?
-- I didn't necessarily think it was a fair comparison (siggy vs. nikon) but I'm not to familiar with Nikon and after doing some limited research I kept reading that the 70-300 AF speed was superb; but price wise they seem to be in two different categories.

For those of you that have handled both, how much bigger is the D7000 than the K5?

[wshi]

I just went to Nikon from the K20D. Needless to say, the D300's AF smokes the K20D but the IQ is almost identical, IMO. High iso may be a touch better in the Nikon, but like I said the real difference lies in the autofocus and fps.

I've been using an old AF 300mm f/2.8 lately for sports and it works wonders. Even though if it needs to go through the entire range it's painfully slow, when switching between targets and tracking it hasn't let me down. It's pretty damn cheap too compared to a similar lens from the pentax FA* line.

If money isn't an object, consider a 300 f/2.8 + an excellent AF-S 80-200 f/2.8 combo.

[dylansalt]

With regards to the size comparison.

I have a K10D which I used a lot shooting climbing comps indoors and outdoors and seriously considered the K5 and ended up with the Nikon D7000.

I actually find the bigger body more comfortable to hold and balance and especially to hold one handed - you would need a battery grip on the K5 to get a similar feel and balance.

If the cam is well balanced the size issue gets forgotten - point in case is the Canon 1D MK1V which looks huge and heavy but when in your hands it doesn't.

But if you are going to buy Nikon aps-c then don't settle for anything less than the D7000 if you can afford it.

[Samsungian]

I really enjoy my Nikon 70-300 VR II lens.

I don't get the image quality problems mentioned above at 200-300mm, not on my lens.

Its handy, small, ridiculously good IQ. VR works in an instant.


If you visit a Nikon forum you'd find out most owners love theirs too, its rare to see somene's unhappy with it:


70-300 VR ultimate P&S??? - FM Forums

[apisto]

I do not know if I can directly respond to the OP's question, but I have, or have had, much of the equipment being discussed. So I will throw some quick observations out.

The AF on the D7000 is better than the AF on the K5 for action. The D300s/D700 is better still. As an aside, I absolutely hate the D7000 ergonomics. I like the K-5 and D700/D300s ergonomics equally well, although they are different. Of those, plus my old K20D, I kept the K20D, D300s and D700. I am considering selling my D300s, as well.

Of the three lenses being discussed, the Sigma 100-300 F4(I have only tried in Nikon mount), Tamron 70-300, and Nikon 70-300, the Sigma I found to have the snappiest focusing for action shots. Optically it is the best of the three, as well. It is also the largest and most expensive. The Nikon and Tamron are pretty compareable. The Nikon colors are a little better than the Tamron, but the Tamron has a little more sharpness and contrast, along with possibly more effective VC. Keep in mind I have only tried two of the Sigmas and one each of the Tamron and Nikon. I kept the Sigma and Tamron and sold the Nikon. Although the Sigma is a better lens, I often put the Tamron in my bag instead because of size and weight.

EDIT: I should clarify I am talking about the new Tamron 70-300 VC.

[jstevewhite]

Of the three lenses being discussed, the Sigma 100-300 F4(I have only tried in Nikon mount), Tamron 70-300, and Nikon 70-300, the Sigma I found to have the snappiest focusing for action shots. Optically it is the best of the three, as well. It is also the largest and most expensive. The Nikon and Tamron are pretty compareable. The Nikon colors are a little better than the Tamron, but the Tamron has a little more sharpness and contrast, along with possibly more effective VC. Keep in mind I have only tried two of the Sigmas and one each of the Tamron and Nikon. I kept the Sigma and Tamron and sold the Nikon. Although the Sigma is a better lens, I often put the Tamron in my bag instead because of size and weight.

Agree on the Tamron. I've got the 70-300, and the only reason I don't throw it out a window is that it reduces the weight of my bag by 3lbs. I've got Bigma (that trounces the Tamron at every focal length - expected, though, the Tammy was 1/5 the price) and a Tamron 180 f2.5 + 1.4TC (for ~270mm f3.8), and the DA* 50-135, and all three make the 70-300 look like trash. But they all three weigh at least twice as much (and cost at least 4x as much).

[highyellow1]

Apisto, do you think the K5 is capable of tracking motorcycles? I know initially my skill will be the limiting factor but want something I can grow into.

[highyellow1]

So I thought I found a place that had a leftover Sigma 100-300 but they are out. Which makes this decision even harder.