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05-06-2010, 03:45 PM   #16
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QuoteOriginally posted by Voe Quote
The only two changes I want from Pentax is a FF camera with up to standard autofocus system ala Nikon or Canon. I'm sick of missing street photography shots due to focus hunting and misfocusing. I would have switched to Nikon if it wasn't for the Pentax Limiteds.
As you probably know much more in the area, do you feel it's possible that contrast-detect autofocus can become as fast as phase-detection autofocus? Got any idea how the current Panasonics systems compare to higher end Nikon and Canon systems?

Is it possible to do video with phase-detection autofocus? (I don't know where the phase-detection auto-focus is located in the camera, could google it.)

If not I assume that if demand for video feature is big enough, which I assume it will be, there will be a need to increase contrast-detection auto-focus speeds and in that case which way is the better choice to catch up with Nikon and Canons auto-focus reliability and speeds?

05-06-2010, 03:55 PM   #17
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Does the DOF depend on sensor size or sensor to lens length or both?

Will a four-thirds lens mounted on a micro four-thirds camera give the same DOF as it would on a four-thirds DSLR? (Stupid question maybe because the sensors is equal in size and I guess the length will be the same to ..)

Does it only depend on sensor size? Is DOF on a four-thirds and a micro-four thirds lens the same?
Or does it depend on glass size or distances or anything? All?

Since FF is supposed to have shorter one I guess it's sensor-size related? So four-thirds is just "worse" in this area?


Sorry for stupid newbie question. I'll probably read up on those areas to =P
05-06-2010, 06:18 PM   #18
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QuoteOriginally posted by aliquis Quote
As you probably know much more in the area, do you feel it's possible that contrast-detect autofocus can become as fast as phase-detection autofocus?
Yes, most definitely. And not only faster, but more precise, and with no need to adjust it, ever.

QuoteQuote:
Got any idea how the current Panasonics systems compare to higher end Nikon and Canon systems?
I don't know about the Panasonics, but the Olympus focus slower than my K10D, but not by much. The Samsung NX10 (with kit lens) focuses faster than my K10D.

QuoteQuote:
Is it possible to do video with phase-detection autofocus? (I don't know where the phase-detection auto-focus is located in the camera, could google it.)
Not really practical (or possible), as the AF sensor is separate from the image sensor. In DSLRs the AF sensor is located opposite the pentaprism below the mirror.

...
05-06-2010, 06:37 PM   #19
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QuoteOriginally posted by aliquis Quote
Does the DOF depend on sensor size or sensor to lens length or both?
Sensor size only.

QuoteQuote:
Will a four-thirds lens mounted on a micro four-thirds camera give the same DOF as it would on a four-thirds DSLR? (Stupid question maybe because the sensors is equal in size and I guess the length will be the same to ..)
The DoF will be the same because the sensors are the same size. But the register distances are different, with micro-4/3 being shorter than standard 4/3.

QuoteQuote:
Since FF is supposed to have shorter one I guess it's sensor-size related? So four-thirds is just "worse" in this area?
FF has about 2 stops less DoF than 4/3 for equal field-of-view and aperture used. That's neither "worse" not "better", it just is

...

05-06-2010, 06:50 PM   #20
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QuoteOriginally posted by Miserere Quote
Yes, most definitely. And not only faster, but more precise, and with no need to adjust it, ever.



I don't know about the Panasonics, but the Olympus focus slower than my K10D, but not by much. The Samsung NX10 (with kit lens) focuses faster than my K10D.

I did some tests a while back, and the Panasonic G1 was fast:

Here is the order of fastest to slowest:

Panasonic G1 (almost instant)
Canon 50D (very close to the G1)
Olympus E30 (quite a bit slower than the 50D)
Pentax K7 (slightly slower than the E30)
Sony A380 (slightly slower than the K7)
Nikon D300 (quite a bit slower than the A380)
Olympus E-P1 (a big margin slower than the D300)

(based on using the standard kit lens)

I did tests, first close (<0.5m), then 10m, then <0.5m. It did multiple tests, one against the other to establish the fastest to slowest. However, it was not a lab test, just in shop, with all of those cameras on hand.
05-06-2010, 08:10 PM   #21
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If they would improve there AF they would be ontop in no time.
05-06-2010, 10:06 PM   #22
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QuoteOriginally posted by Miserere Quote
Yes, most definitely. And not only faster, but more precise, and with no need to adjust it, ever.
K, I thought maybe the usual technique used in DSLR was superior/faster/whatever since it was used there. Guess not then.

It's only used because the viewfinder uses light form the lens so the mirror block the sensor and hence you can't use that for focus?

So throw out the penta-prism already and make it EVF =P
(Which would also be bright in all occasions, show shutter speeds/"blur" as it really is, real DOF (you do have a button to preview it on regular DSLRs? But normally the lens is at the biggest aperture?), WB if using jpeg, whatever crap you want on top ..)
QuoteOriginally posted by Miserere Quote
I don't know about the Panasonics, but the Olympus focus slower than my K10D, but not by much. The Samsung NX10 (with kit lens) focuses faster than my K10D.
Ok, but the Olympus is supposed to be much slower than the Panasonic. I think I may have read how he Samsung actually may had been worse then the Olympus. In any case the Panasonic is faster.
QuoteOriginally posted by Miserere Quote
Not really practical (or possible), as the AF sensor is separate from the image sensor. In DSLRs the AF sensor is located opposite the pentaprism below the mirror....
Ok, yeah, I though it was up there somewhere =P

Can't be that hard to switch to contract-detection focus and EVF since that's what all compacts use .. And there's always faster CPUs around if that's the issue =P
QuoteOriginally posted by dnas Quote
I did some tests a while back, and the Panasonic G1 was fast:

Here is the order of fastest to slowest:

Panasonic G1 (almost instant)
Canon 50D (very close to the G1)
Olympus E30 (quite a bit slower than the 50D)
Pentax K7 (slightly slower than the E30)
Sony A380 (slightly slower than the K7)
Nikon D300 (quite a bit slower than the A380)
Olympus E-P1 (a big margin slower than the D300)

(based on using the standard kit lens)

I did tests, first close (<0.5m), then 10m, then <0.5m. It did multiple tests, one against the other to establish the fastest to slowest. However, it was not a lab test, just in shop, with all of those cameras on hand.
Thanks.
Kinda annoying since that probably mean that the 11-AF point 550D probably suck at focusing compared to the DMC-GH1 (no real news there really =P)



Sooo.. if phase-detection AF is worse and EVFs are good isn't it very obvious that the mirrors will go? And then there will be no reason to keep the camera bigger than necessary so they will shrink and in that case is it necessary with a specific length from lens to sensor? (no?) So all old lenses will get outdated? (no?) Or is it just that part of the image will be cropped if you put the sensor closer to the lens? (yes?) ... but that will make use of bigger glass than necessary (yes?)

Do one want to buy into a dying breed?
05-06-2010, 10:16 PM   #23
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Would this 50mm/0.95 lens (NOKTOR - Ultra Fast Lenses - Products) have a similar DOF on micro four-thirds as say 85/1.8 or 100/2.8 (or 85/1.4) glass on aps-c?

In that case I guess it may be ok on a future DMC-GH2 with global shutter + the kit-lens of 12-75/2.5-3.3 OIS.

"I have to say that you can buy another 50mm lens that will perform better in almost every way for an extra $300 or so. I am talking about the Voigtlander 50 Nokton 1.1. It is a sharper lens, has better color, better contrast and is almost as fast with a 1.1 aperture. But, that lens is for Leica M mount and you will need an adapter to use it, so more expense. It’s also a fatter (larger) lens.", The Noktor 50 f/0.95 Lens Review | STEVE HUFF PHOTOS

So say 12-75/2.5-3.3 + 50/1.1 then.

Voigtlander 50/1.1 Nokton
http://www.stevehuffphoto.com/2009/11/16/the-voigtlander-nokton-50-1-1-lens-review/

Smarter to wait? But then the summer will be gone ..


Or should anything except M-mount be banned and everything use it as is or by adapter?

05-06-2010, 10:17 PM   #24
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I think there is misunderstanding, here. There is no way today that even the best contrast phase focus can bit even a middle range reflex focussing system. Even if the smaller sensor induce larger DOF, DSLR are still the fastest camera for accurate and fast focussing.
05-06-2010, 10:31 PM   #25
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QuoteOriginally posted by youky63 Quote
I think there is misunderstanding, here. There is no way today that even the best contrast phase focus can bit even a middle range reflex focussing system. Even if the smaller sensor induce larger DOF, DSLR are still the fastest camera for accurate and fast focussing.

Well according to what I tested, the BEST Contrast Detection AF (on Micro 4/3, G1) was about as good as Phase Detection AF used in DSLRs.
The worst Contrast Detection AF(on Micro 4/3, E-P1) was much worse than Phase Detection AF used in DSLRs.

QuoteOriginally posted by dnas Quote
I did some tests a while back, and the Panasonic G1 was fast:

Here is the order of fastest to slowest:

Panasonic G1 (almost instant)
Canon 50D (very close to the G1)
Olympus E30 (quite a bit slower than the 50D)
Pentax K7 (slightly slower than the E30)
Sony A380 (slightly slower than the K7)
Nikon D300 (quite a bit slower than the A380)
Olympus E-P1 (a big margin slower than the D300)

(based on using the standard kit lens)

I did tests, first close (<0.5m), then 10m, then <0.5m. It did multiple tests, one against the other to establish the fastest to slowest. However, it was not a lab test, just in shop, with all of those cameras on hand.
Now the tests weren't "lab controlled", but these were the results I got. Take them or leave them!

I was surprised by some of the results, namely the G1 being so fast, and the Nikon D300 being so slow. These results may have been dependent on the lens that was attached at the time, but I had no control over that.
05-06-2010, 10:38 PM   #26
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QuoteOriginally posted by aliquis Quote
Sooo.. if phase-detection AF is worse and EVFs are good isn't it very obvious that the mirrors will go? And then there will be no reason to keep the camera bigger than necessary so they will shrink and in that case is it necessary with a specific length from lens to sensor? (no?) So all old lenses will get outdated? (no?) Or is it just that part of the image will be cropped if you put the sensor closer to the lens? (yes?) ... but that will make use of bigger glass than necessary (yes?)

I wouldn't say phase detection is worse than contrast detection. The best contrast detection (in the Panasonic G1, GH1, GF1 and G2) is very good. However, clearly not all contrast detection AF is good, but most phase detection AF is good.

The best EVF are good for what they are, but in low light, they have a slow refresh rate. Mind you, in low light OVF are just dark!!!

So my point of view is that the best contrast detection AF is ready to tackle the phase detection AF. But while very good, the best EVF have a little more to go.
05-07-2010, 01:17 AM   #27
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The little in shop test I made of D300/D700 AF was very disappointing but:
* it was in relatively low light conditions (shop)
* it was in crap WB
* it was with a Nikkor 50/1.8 D

My K-7 focus faster for sure with an FA50 but again, with my Sigma 28/1.8 it is really slow. There's so much variables playing here...
05-07-2010, 01:18 AM   #28
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QuoteOriginally posted by dnas Quote
I did some tests a while back, and the Panasonic G1 was fast:

Here is the order of fastest to slowest:

Panasonic G1 (almost instant)
Speed is one thing. Accuracy another.
05-07-2010, 01:19 AM   #29
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QuoteOriginally posted by Urkeldaedalus Quote
It revealed that Pentax is working on something big for this year. I haven't heard an indication of that yet in any other article.

It also was the closest that I've seen a Pentax rep come to confirming they are going to make an EVIL camera of some sort, even if he only confirmed it to the extent that he said Pentax Japan might be open to the idea.

Full of vagueness, sure, but what else were you expecting, prices and release dates?
Yes, you are right. On the other hand, Pentax has been delivering new products each year.
History is not a guarantee for the future, but often a very good indication...

On the Evil thing, it could go in every direction still. However, if the market is moving in that direction, does anybody with some business sense believe Pentax in the end could stay behind?

- Bert
05-07-2010, 06:19 AM   #30
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QuoteOriginally posted by dnas Quote
I did some tests a while back, and the Panasonic G1 was fast:

Here is the order of fastest to slowest:

Panasonic G1 (almost instant)
QuoteOriginally posted by blende8 Quote
Speed is one thing. Accuracy another.
I own a G1 and a GF1, and I find the AF both fast and accurate. They show exactly where they have focused on the LCD/EVF, and I can't say as I've ever been unhappy with the focus performance.
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