need faster AF than a K20D..


Aug 5, 2009
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#1
.. for macro.

I don't think I want to spend for a K-5. So I'm down to two options: (1) get a K-r; (2) switch to Canon EOS 60D + 100mm USM Macro.

Switching to Canon will be expensive as Pentax resale prices are in the toilet and I'll have to duplicate a number of items. But the 60D is a known quantity AF-wise (pretty much same as the 50D which is quite good) and the 100mm USM Macro has a ring drive and is internal-focus, unlike the Pentax D-FA 100mm which gets seriously long as you focus close.

I don't expect the K-r to match a 60D's AF performance but how much better is it than a K20D?

I realize that a 60D + Canon macro costs >> K-5.

But.. I don't trust Pentax in the AF department anymore! I find it almost impossible to believe that a K-5 + D-FA 100mm could even approach the AF performance of the 60D + Canon macro.
 

fengwei

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#2
If you really want faster AF, go for a Canon, but not the 60D. Get something better than 60D.

But I don't understand why you need fast AF for macro ...
 

detritus

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#3
agree with FW... i don't see how AF helps for macro, esp as you go down to 1:1 or larger than life size for macro :dunno:
 

night86mare

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#4
btw, most macro people use MF.

i use a cheap k-r with cheap tamron 70-300 (and that's a 1:2 lens) to take these pictures, i didn't know you have to get fast AF for macro one... fyi, even a 60d will have problem locking focus on macro, because dof so tiny, is easy to focus on background instead.





suggest you perfect your macro technique, i can easily find many good pictures taken with k20d and macro lens for the purposes of encouraging you and showing you that it can be done.. there is a lot more other things to observe other than good focusing, also how to approach the insects, etc will help you a load. you have to understand what you are shooting, if not, how to shoot?
 

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Aug 5, 2009
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#8
Hmm. Maybe it's just a case of "the grass is always greener on the other side.."

The really annoying thing about the K20D + D-FA is the excessively long focus throw and the tendency of the body to hunt from one end of the range to the other, every time you half-press the shutter! what I'd like is for the AF to get things into the range, then touch up with MF. What actually happens is that the AF is pretty worthless and I'm stuck with MF.

In which case I should have stuck with my ebay special $100 Vivitar macro rather than ponying up for the Pentax macro... :bheart:

I know about that guy with a K200D.. and yes, anything is possible. Check also Mark Plonsky who did really good macro with a Canon G1 point-and-shoot oh, ten years ago (in fact I think a P&S is a better macro camera than a DSLR because the DOF is much deeper). But faster AF would make life more pleasant.

Back in Canon-land, what's there that's faster than a 60D? 7D or 1-series. The 1-series is way out of my budget. I've seen some really good BIF taken with the 60D (which is pretty much a 50D) so I do know that its general AF performance is very good.

K20D.. it maddeningly takes several seconds to lock focus. And sometimes still gets it wrong.. I think this is well-known with Pentax, the body drives the lens to the correct focus quite quickly, then spends even more time fine-tuning the focus.

My recollection of my friend's (entry level!) 400D plus some ring drive lenses is that they focus much, much faster and don't hesitate at the end like the K10D and K20D do.. I think this is how Pentax made the AF "faster" in the K-m.. by getting rid of the focus confirmation step.
 

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night86mare

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night86mare

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#10
personally, i never use AF for macro. i think AF for macro lens is for more normal use, e.g. shooting people. btw, a long range is good for macro, means you can get very, very precise macro focusing to get the image tack-sharp.

that said, the k20d was never a king of AF.. perhaps the k-x, k-r and k-5 can do better, but once again, sticking to manual focus is probably better. after all, you only are going to use the closer end of the focus. perhaps it would be useful to have a "limit" range on lenses, like some do, so that focusing on macro side will be easier.

i think you are paying for more than just "AF" on the pentax macro, really.


Hmm. Maybe it's just a case of "the grass is always greener on the other side.."

The really annoying thing about the K20D + D-FA is the excessively long focus throw and the tendency of the body to hunt from one end of the range to the other, every time you half-press the shutter! what I'd like is for the AF to get things into the range, then touch up with MF. What actually happens is that the AF is pretty worthless and I'm stuck with MF.

In which case I should have stuck with my ebay special $100 Vivitar macro rather than ponying up for the Pentax macro... ::bheart:

Thing is, what's there that's faster than a 60D? 7D or 1-series. The 1-series is way out of my budget. I've seen some really good BIF taken with the 60D (which is pretty much a 50D) so I do know that its general AF performance is very good.

K20D.. well indoors it maddeningly takes several seconds to lock focus with the FA 50. And sometimes still gets it wrong.. I think this is well-known with Pentax, the body drives the lens to the correct focus quite quickly, then spends even more time fine-tuning the focus.

My recollection of my friend's (entry level!) 400D plus some ring drive lenses is that they focus much, much faster and don't hesitate at the end like the K10D and K20D do.
 

Aug 5, 2009
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#12
I do use manual focus..

My K20D has a magnifying eyepiece (a Nikon DK-21M, ironically) and a split-image screen. I also have a ton of MF lenses (some of which I'm now trying to get rid of..)

Bottom line is, MF all the time (or most of the time) isn't fun.

Also the lack of a focus limiter on the D-FA 100mm hurts when its used as a normal telephoto and it does its wild hunt all over the place.

I guess my point should be I want faster AF in general. Will a K-r give me noticeably faster AF, or should I jump ship to Canon?

Ironic that I came from Canon and went Pentax (K10D) because of the huge VF, weatherproofing, and compatibility with MF lenses. I guess my MF phase is over..

BTW this was my 90mm Vivitar (Komine) MF macro (cost me $100 USD on ebay!) that I got rid of:



It is a true macro, goes to 1:1 with a 540-degree focusing rotation (yes 1 and 1/2 full turns).
 

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night86mare

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#13
I guess my point should be I want faster AF in general. Will a K-r give me noticeably faster AF, or should I jump ship to Canon?

Ironic that I came from Canon and went Pentax (K10D) because of the huge VF, weatherproofing, and compatibility with MF lenses. I guess my MF phase is over..
i really don't know, i never found a major problem with the k20d except in really bad lighting, i.e. OUTSIDE void decks at night in the carpark, shooting cats.

what i can say, as a user moving from k20d to k-r is that AF is much improved in low light, in part because of the AF assist lamp, in part because it just seems better.

but after i've read all your posts, i have a feeling you might not be satisfied anyways.. :dunno:

maybe it's unavoidable, you should just get a nikon d3 or a canon 1d mark IV. this way, even if it doesn't work well enough for you, you won't have to upgrade anymore, since that's the best there is. well, you could switch brands once, and then you'd be finito. :bsmilie:
 

Aug 5, 2009
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#14
Hahaha! actually a 1D Mk II is affordable enough now, if ancient (DIGIC II). The thought has crossed my mind..

I'm not saying the K20D is problematic.. it works well enough. But I actually think my old Canon 350D focused faster! (I would compare, except the 350D blew up which is why I ended up with the K10D.. back then I was a lot into M42 lenses so I didn't care about AF). Besides there are all the reports of Pentax users jumping ship and being blown away by the improved performance in Canikon land..

Another thing: I do have an AF illuminator for low light (the AF360FGZ has one). It does improve performance quite a bit.
 

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detritus

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#16
Hmm. Maybe it's just a case of "the grass is always greener on the other side.."

The really annoying thing about the K20D + D-FA is the excessively long focus throw and the tendency of the body to hunt from one end of the range to the other, every time you half-press the shutter! what I'd like is for the AF to get things into the range, then touch up with MF. What actually happens is that the AF is pretty worthless and I'm stuck with MF.

In which case I should have stuck with my ebay special $100 Vivitar macro rather than ponying up for the Pentax macro... :bheart:

I know about that guy with a K200D.. and yes, anything is possible. Check also Mark Plonsky who did really good macro with a Canon G1 point-and-shoot oh, ten years ago (in fact I think a P&S is a better macro camera than a DSLR because the DOF is much deeper). But faster AF would make life more pleasant.

Back in Canon-land, what's there that's faster than a 60D? 7D or 1-series. The 1-series is way out of my budget. I've seen some really good BIF taken with the 60D (which is pretty much a 50D) so I do know that its general AF performance is very good.

K20D.. it maddeningly takes several seconds to lock focus. And sometimes still gets it wrong.. I think this is well-known with Pentax, the body drives the lens to the correct focus quite quickly, then spends even more time fine-tuning the focus.

My recollection of my friend's (entry level!) 400D plus some ring drive lenses is that they focus much, much faster and don't hesitate at the end like the K10D and K20D do.. I think this is how Pentax made the AF "faster" in the K-m.. by getting rid of the focus confirmation step.
its normal for macro lenses to have long focus throw because pple usually MF and u need the focus throw for precision. as mentioned earlier, DOF is so shallow that u need the precision.

may i ask what kind of subjects u normally shoot? are u shooting butterflies? dragonflies? or spiders and bugs? and at what level of magnification?

slightly bigger subjects like dragonflies and butterflies shot at a comfortable working distance is technically not macro, but close-up. and yes, faster AF helps for that.

but for smaller insects, like spiders, bugs and flies, AF is counter productive, esp if u want 1:1 magnification. for that, the focus clamp of the dfa 100 is more useful where u extend the focusing ring out all the way, lock it, and attain focus by moving slowly towards the subject.
 

Aug 5, 2009
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#17
all good points, and yes normally am not at 1:1.

i really ought to get that macro focusing rail..
 

night86mare

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#18
Besides there are all the reports of Pentax users jumping ship and being blown away by the improved performance in Canikon land..

Another thing: I do have an AF illuminator for low light (the AF360FGZ has one). It does improve performance quite a bit.
i'm not blown away by the performance in canikon land..

and more importantly, i'm not blown away by the pricing either. :bsmilie:
 

night86mare

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#19
slightly bigger subjects like dragonflies and butterflies shot at a comfortable working distance is technically not macro, but close-up. and yes, faster AF helps for that.

but for smaller insects, like spiders, bugs and flies, AF is counter productive, esp if u want 1:1 magnification. for that, the focus clamp of the dfa 100 is more useful where u extend the focusing ring out all the way, lock it, and attain focus by moving slowly towards the subject.
butterflies come in many sizes leh...

the lesser? or is it common? grass blue, and the branded imperial, for example, are very small butterflies. the first i have mentioned is the really small butterfly that flits around, looks greyish. very cute close up! :)

and butterflies are better shot with MF... if you keep AF and miss, you can say bye bye, they are very, very jumpy subjects.
 

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