[medbooks321]

Ever since I got my K100D two years ago and found this forum, I've learned a lot. My Canikon friends all tried to talk me out of Pentax, but I got all defensive and touted things like cost, IQ, etc. I was happy as a clam. Then today, I walked into my local store and I played with the D700. Dang. Now I know what I'm missing.

The autofocusing.

Over the years, I've found myself bringing my camera primarily to lots of low-light, birthday party/restaurant/awards ceremony/wedding kinds of situations. I know this has been discussed before, but my K100D hunts all the time, still spot-focuses on the plant and not the person, and rarely gives you the razor sharp "nose-and-eyes" kind of focusing you'd like to see. I bought an FA35/2 (great lens!) and pump up the ISO, but it's not the noise -- I still miss most of my shots from poor focusing. I've resorted to manual focusing at times, but it's too slow for candid work.

How can I make my K100D focus faster and better in low light?

I've tried out the K20D + DA16-50 combo, and ths HSM is better, but the autofocusing still feels the same, with results to match. I was blown away today by the D700 + 24-70/VR system. Granted, price points are totally different. But what do you guys think? Instead of upgrading to the great IQ of the K20 once I start making a real salary (woohoo!) in 6 months, I'm now considering the D90 or D300. It's very sad.

For those of you who are sticking with Pentax, how have you made it focus better in low light? Or is it a matter of skill? Perhaps I need to practice more ...

[hinckc]

Hi medbooks321,

I've used all of K100 -> K10 -> K20. Here are my thoughts.

1) K100 and K20, IQ wise, are far better than the K10 in low light, though the K10 and K20 beat the K100D in AF speed, regardless of light.

2) When the lights are really low, MF gives me great results. Does it take practice? Yeah, for me, it did. But with some practice, I've been getting great results. (you can click this image for a bigger version -- K10 @ISO1100 )



3) If you are truly compelled to use AF, get a AF540FGZ and set it to Spot Beam. The beam actually really assists in low light. The downside of this solution is that your camera goes from big to huge.

4) Lastly, and leastly, aiming your camera at a vertical, high contrast line, (auto)focusing, and then re-composing will speed things up a bit. Just keeping a high contrast, vertical line in the center of the frame will help.

I've also been practicing with de-coupling AF from the shutter button. The K100D doesn't have a dedicated AF button, but you can set the OK button to this function. See pg 126 in the manual for details. This, too, requires practice, but I really like leaving the camera in AF-C, and using the AF button to focus. That way, I can take a shot whenever "the moment" arrives, all the while tracking my subject as best as the AF can do until I'm satisfied with the focus. When it finds it, I can leave the AF button alone until I shoot.

Good luck!

-Chris

[Marc Sabatella]

Indeed, Pentax is not known for great low light AF performance. But there are a couple of things to consider:

- You mention the FA35/2. Well, DOF at f/2 is thinner than at f/2.8. Enough so that it is indeed tougher to get both eyes and nose in focus.

- The light in the store was probably better than what you are comparing to in ordinary home settings, so unless you were specifically comparing your camera in the same store, it might not have been a fair comparison that way, either.

- You say you tried the 24-70/2.8 VR. As far as I know, there is no such lens. The only 24-70 that shows up in my searches has no VR, and the discussions that turned up consisted of people doubting there ever would be one. Something to consider, after getting spoiled by having SR on every lens for Pentax: you'll have to live without it for most lenses with Nikon.

But there is also no getting around the fact that the D700 has lots more focus points and a more modern AF system - meaning it is more likely to choose the "correct" subject to focus on. And that it has a built-in AF assist lamp, meaning the AF will be faster and more accurate in low light, too.

How can I make my K100D focus faster and better in low light?

You could use a lens that is known to focus faster than the FA35, such as the DA40. You can use center-point focusing and point the camera directly at the subject rather than make the camera guess, which takes time, and also might lead to it guessing wrong (eg, the plant instead of the person). You can always then recompose as desired, and possibly touch up the focus with quick shift (the latter also requires a DA lens).

You could also work on your MF skills. Most of my low-light shooting is done with old MF lenses. With candids, I focus before I need to take the shot, then wait for the right moment to snap. You could also consider the Katz Eye focus screen or the O-ME53 magnifying eyecup to aid in manually focusing.

And you can hope that in six months, if you are considering getting a new camera, Pentax may have something with a much improved AF system. Personally, with my DS, I lost *far* more shots to shake than I did to poor focus. You couldn't pay me to go back to a camera body with no built-in stabilization.

[deejjjaaaa]

I bought an FA35/2 (great lens!) and pump up the ISO, but it's not the noise -- I still miss most of my shots from poor focusing. I've resorted to manual focusing at times, but it's too slow for candid work.

buy MF screen,
buy O-ME53,
buy 50/1.4 or 50/1.7,
train your MF skills and sometimes use catch in focus/focus trap,
adjust AF through DEBUG menu for a tungsten light if you happen to get FF/BF,
decouple AF from the shutter button / prefocus / focus and recompose,
buy D300,
buy Hoya itself and kick their a$$'

[Mallee Boy]

I am non-plussed at the comparison offered...a D300 body @ some $1600us; a D700 body @ some $3000us (B&H current prices)......compared to a humble 2 yr old K100D..?? which probably cost around $600us new. Even the K20D body is only $1000us.
And they are Body Only prices, watch the price differential blow out when you start bolting something onto the front of it.

I am not sure if Pentax should feel honoured or humbled at the comparison.

Its been said often enough, if the AF is that important to you, and you have the $$$, then go for it and good luck. For me, AF is not that important and I do not have that sort of money to spend....so Pentax does the job beautifully for me and my budget. I just have to learn to compromise in those situations.

I know this will be interpreted as "fanboyism" by some, but gee whiz people, lets just be a little fair in our comparisons.

As to "how to make the K100D focus better in low light?" , sorry mate, you can't expect the sort of performance you seek from an entry level camera, certain lenses may help a bit (50mm f1.4 perhaps?), but the reality is the camera is not going to perform like the more expensive models you have named.

Cheers
Grant

[kleung]

Are you talking about AF w/ center-focus only, or AF with all 11 points? On my k200d, I use center-focus with the center sensor only and recompose. I don't have any issues with low-light. I cannot imagine that the cross-type sensor that Pentax has is that different from D300's or D700's. Those got more focus points, but the sensitivity of each one should be comparable to the cross-type sensors in Pentax's.

Are you sure you cannot just focus and recompose w/ the center sensor to solve the perceived problem?

[troywhite]

I can't believe you are comparing a K100D to a D700. That's just nuts.
Try comparing it to the D40(x) or something.

[philmorley]

whether there is as much difference as k100d -> d700 etc I couldn't say but there is a lot of difference between k100d and k10d/k20d.

[soccerjoe5]

i had the D40 and D80 with the AF-S lenses and boy they're MUCH faster than my K20D + 16-50. But I am happy with my gear. Upsides and downsides to each system/brand.

For work/coverage I'd be happier with a Nikon system (better AF and flash system), but I do a lot of personal shooting and I prefer my Pentax for it.

[wlachan]

Hi medbooks, if low light AF is what you need, and you need it for work, don't kid yourself just get Canon or Nikon. You are not deep in Pentax so it make senses to make the move. I LOVE Pentax primes, but I hate the ill-designed AF-540FGZ, most poorly-constructed Pentax AF zooms, and the inferior AF. If the subject was still, you can still work around. But if they move, I have had much more in focus shots with the 40D (the lenses are important too of course). I have also found the much debated Canon open-circuit AF being less accurate is just a myth.

[PDL]

Ever thought of de-coupling AF from the shutter button? Set the focus (just like manual) and blast away.

Look Ma - no hunting.

Learn to manual focus and dump the idiot-proofed AFontheshutterbutton hunting gimick.

The Elitist - formerly known as PDL

[wlachan]

I cannot imagine that the cross-type sensor that Pentax has is that different from D300's or D700's. Those got more focus points, but the sensitivity of each one should be comparable to the cross-type sensors in Pentax's.

All Pentax DSLRs have very wide AF sensor. Each of the 9 cross sensors overlap each other a little. The pro with this approach is that to non-educated users, they can just point and shoot, and something will be in focus. The con is that if you try to pin-point the focus, especially when the target is smaller than each sensor, the camera might pick up the higher contrast subject instead of what you have in mind. A typical situation is a person in front of a high contrast background. Pentax DSLRs would simply attract to the background instead of the person. If the sensors were made smaller, this problem would not occur.

AF sensitivity is another weak area as the EV drops, AF speed and accuracy drop too for any cameras, even with Canon or Nikon. However, Pentax DSLRs seem to have a severe drop when below 4EV (typical indoor conditions). And if anyone got the chance to try them out at local store, have lowend Canon XSi, Nikon 40D, Olympus E-520 and Pentax K200D with their kit zooms ready. Just try to AF tracking a walking person toward you, Pentax would be amount the most sluggish.

[rfortson]

If you've got the bucks to drop on the D700, then why are you "getting by" with the K100D? Seriously, the D700 and D300 are great cameras and the AF should work better for that price.

In my usage, I've never really had a problem with AF but I guess I'm not using it in the same situations as you. I did notice once at my daughter's pre-school event (indoors in a dim auditorium) that the Canon user and Nikon user were constantly refocusing while my K20D and DA*50-135 was spot on. I'm pretty sure they were using a cheaper kit lens, so (again) I'd expect my system to focus where theirs wouldn't.

As for focusing on people walking towards or away from me, I guess I'm doing something differently, but I've never had that problem. I've seen others post examples of it, so I'm sure it exists for them, but I've just never experienced it. I took about 100 shots of a 10k race, and all but 2-3 of the shots were dead-on, and I made sure to use AF-C and shoot people coming towards me, going away from me, and crossing perpendicular to me. I was using the K20D and the DA*50-135 again. Granted, there was a lot of light, so I expected nothing less. However, some of the posts I've seen reporting problems showed their kids outside in the yard, so I guess it was a fair comparison. (Full disclosure - I did have a few problems shooting a rodeo at night. I had to shoot af f/2.8 and ISO 2000 or higher and my keepers went down there. I'd expect other brands to struggle as well, but maybe they'd get a higher percentage. Again, for 50%-200% more cost, I'd expect nothing less.)

Back to the original point though. If you have the money to go to the D300 or D700, go for it. I'm sure the AF will work for you, and there are a lot of other reasons to go for it. You'll lose in-body SR, but you can buy all those nice VR lenses to make up for it.

[wlachan]

As for focusing on people walking towards or away from me, I guess I'm doing something differently, but I've never had that problem. I've seen others post examples of it, so I'm sure it exists for them, but I've just never experienced it. I took about 100 shots of a 10k race, and all but 2-3 of the shots were dead-on, and I made sure to use AF-C and shoot people coming towards me, going away from me, and crossing perpendicular to me. I was using the K20D and the DA*50-135 again. Granted, there was a lot of light, so I expected nothing less. However, some of the posts I've seen reporting problems showed their kids outside in the yard, so I guess it was a fair comparison. (Full disclosure - I did have a few problems shooting a rodeo at night. I had to shoot af f/2.8 and ISO 2000 or higher and my keepers went down there. I'd expect other brands to struggle as well, but maybe they'd get a higher percentage. Again, for 50%-200% more cost, I'd expect nothing less.)

I was refering to indoor AF ability. My point is even Olympus could achieve better AF in low light (and they used to lag behind) than Pentax. With sufficent light, Pentax could be fast.

[regken]

This is a hobby and is supposed to be fun so why kill yourself trying to make something work that is not all that good. If you can afford the extra dollars do what I did and go to a two camera system. When shooting static items my K10D with primes will come very close to even the D300. When shooting action or low light the Sony A 700 is as fast as the D300. My full set of primes for the k10D and a set of zooms for the A700 along with both bodies cost me less than $3,000. Two bodies, more flexibility, and less money than a D700 makes sense to me.

Regards,