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02-25-2013, 07:28 PM   #1126
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QuoteOriginally posted by Alizarine Quote
The current fastest ones are the UHS-I cards or SDXC ones right? Quite a shame Pentax didn't give speed compatibility for these card formats in the K-5 II/IIs.
Okay things get confusing here.
SDHC, SDXC has nothing to do with the speed only the size of the card.
UHS-I has little to do with speed, it means the card is ready to use the new bus/interface/card reader, when UHS-II comes along those are only be able to be used in the new readers.
CLASS is still the official speed indication but it meanss little these days.

02-25-2013, 07:34 PM   #1127
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I've used a 45Mb/s UHS-I card in my camera for a couple years. But from everything I've read, very few cameras (no Pentax, very few from other brands) do UHS writes. Most max out at 30Mb/s which is class 10 anyway. Seeing 45-95Mb/s writes from newer cameras would be nice. Not that I do much burst shooting, but it'd still be good to have that there.

Regardless of the write speed, though, it certainly helps for copying off the card.
02-25-2013, 07:43 PM   #1128
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QuoteOriginally posted by Anvh Quote
Okay things get confusing here. SDHC, SDXC has nothing to do with the speed only the size of the card. UHS-I has little to do with speed, it means the card is ready to use the new bus/interface/card reader, when UHS-II comes along those are only be able to be used in the new readers. CLASS is still the official speed indication but it meanss little these days.
Oh so that's what it is. Thanks for the clarification.
02-25-2013, 07:54 PM   #1129
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QuoteOriginally posted by Franky2step Quote
this thread has seriously degraded into somewhat of a joke. homey don't play dat

Yes, I agree that some of the banter is rude and uncalled for, and if they keep it up, they will get banned from this thread.

02-25-2013, 08:35 PM   #1130
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QuoteOriginally posted by IchabodCrane Quote
Isn't this determined by the write speed capability of the SDHC card? The speeds vary tremendously with the best "pro" cards having several times the write speed of consumer cards.
I have one of the best cards.
02-25-2013, 09:19 PM   #1131
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QuoteOriginally posted by Alizarine Quote
Oh so that's what it is. Thanks for the clarification.
Sorry it seems they do use UHS for the speed, this wasnt the case when i looked at it. You can actually find UHS card with lower speeds.
https://www.sdcard.org/consumers/speed/bus_speed/

Made a mistake again, those are max speeds of the "bus" not minium speed of the card like Class 10 means
02-25-2013, 10:22 PM   #1132
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QuoteOriginally posted by Clavius Quote
I own a K5 and a 5DMKII and the K5 slows down after a second or maybe two
Unless your K-5 is of the original firmware, the buffer should be sufficient to hold much more than a second's worth of RAW or full-size JPEG images.
02-25-2013, 11:00 PM   #1133
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Additionally, it seems the Nikon d800 and d600 AF systems may have similar problems to the old K5:

D600 . AF in tungsten light: Nikon FX SLR (D1-D4, D600-D800) Talk Forum: Digital Photography Review

http://forums.dpreview.com/forums/thread/3387017#forum-post-50890013

D800 - focus under incandescent light: Nikon FX SLR (D1-D4, D600-D800) Talk Forum: Digital Photography Review

I suspect the next iteration of their design will follow the Pentax route and include some diffractive optics in the AF module to reduce CA.


QuoteOriginally posted by Ayoh Quote
It may not be competitive in sheer number of focus points and associated AF tracking benefits. However, I expect it to be very competitive in low-light sensitivity and accuracy.

The k5II is a significant improvement in AF performance in low light sensitivity and accuracy against the k5. Sensitivity is at -3EV for 9 cross points and a f/2.8 AF baseline is available for the centre point in addition to an effective low-light assist light for total darkness (the assist light algorithm has been revised and now uses very brief and less subject-distracting pulses). The competition:

- is reportedly slow in low light AF with no AF assist light (Canon 5d Mark III) or,
- only achieves -3EV for centre point (Canon 6D)), or
- is sensitivity limited to -2EV (at centre point?) and precision limited by a f5.6 AF system baseline (Nikon 3500). (there are a number of documented test reports of poor AF accuracy of the d800/d4 with f/1.4 lenses on digilloyd.com.)

Having practically evaluated the k5II against some of the competition myself I was quite shocked to find how well the new AF system works. The k5 in comparison thoroughly deserves it's reputation for poor AF speed and accuracy.

I think Pentax engineers definitely deserves credit for the job they did with the k5II as in some ways it is class-leading. The only current lag is in tracking, which is not really relevant for people not interested in sports photography. Personally I would rather they emphasise low light sensitivity in future designs with larger and fewer AF points, rather than target niche sports photography demands and increase AF point count.

Additionally, when Adam compared the k5II to the Canon 7D and concluded that the 7D features a superior AF systems he must have surely not used both cameras indoors. If he had he would find that the 7D (despite its good tracking performance in daylight) has poor low light sensitivity.



Last edited by Ayoh; 02-26-2013 at 01:36 AM.
02-26-2013, 12:24 AM   #1134
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QuoteOriginally posted by Ayoh Quote
Additionally, it seems the Nikon d800 and d600 AF systems may have similar problems to the old K5:
I can personally confirm this, I frequently use studio strobes and they use halogen modelling lights - on their own these lights are very bright, typically around 250W - but that doesn't amount to much when they are behind a large softbox or beauty dish. They have a very low colour temperature and this combination can completely throw off the AF on the D800E with fast lenses. Curiously the Leica S2 and Pentax 645D do not have much difficulty under these conditions, My K5IIs doesn't either. My workaround when using the D800E in the studio is to use a half CTB Dichroic filter* from Lee to bring the colour temperature up to improve accuracy with fast lenses.

*These are made of solid glass and are able to withstand the heat of a 700W modelling lamp, importantly dichroic filters never fade. Hats off to Lee for making these filters.

Last edited by Digitalis; 02-26-2013 at 03:02 AM.
02-26-2013, 12:27 AM   #1135
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It would be interesting if you could try a k5II in the same situation. I have noticed no AF sensitivity to light temperature with the new AF system. The k5 on the other hand had obvious issues.

QuoteOriginally posted by Digitalis Quote
I can personally confirm this, I frequently use studio strobes and they use halogen modelling lights - these lights can have a very low kelvin rating ( at low power settings) and this can completely throw off the AF on the D800E with fast lenses. My workaround is to use a CTB Dichroic filter* from Lee to bring the colour temperature up to improve accuracy with fast lenses.

*made of glass and is able to withstand the heat of a 500W modelling lamp without fading.
02-26-2013, 02:22 AM   #1136
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QuoteOriginally posted by gazonk Quote
I just tested (I shot the screen clock of my computer so it's easy to confirm) a series at 1/500 with my K-5 and got, just as promised, 20 frames at 7fps - i.e. just short of 3 seconds - 2-3 times your claim.
I stated that it felt like maybe 2 seconds. Goes for both my K5's with almost the latest firmware. (I ignored the one for the 560mm lens improvements.) You're now confirming that it's just short of 3. Are you seriously debating fractions of a second? Lets round it up: 3 seconds, still poorly compared to how long a 5D lasts. No matter if it's buffer, sd-card, or buffer-clearance-speed related.


QuoteOriginally posted by gazonk Quote
The only issue I have with the drive mode (which I'm not a frequent user of) is that I miss a medium setting - 7 fps is often too much but less than 2 fps is not enough.
Absolutely, it would vastly improve the endurance. And more control is always better imo.


QuoteOriginally posted by Digitalis Quote
I can personally confirm this, I frequently use studio strobes and they use halogen modelling lights - on their own these lights are very bright, typically around 250W - but that doesn't amount to much when they are behind a large softbox or beauty dish. They have a very low colour temperature and this combination can completely throw off the AF on the D800E with fast lenses. Curiously the Leica S2 and Pentax 645D do not have much difficulty under these conditions, My K5IIs doesn't either. My workaround when using the D800E in the studio is to use a CTB Dichroic filter* from Lee to bring the colour temperature up to improve accuracy with fast lenses.

*These are made of solid glass and are able to withstand the heat of a 700W modelling lamp, importantly dichroic filters never fade. Hats off to Lee for making these filters.
Same issue with my studio lights. K20D, K5 and 5DmkII and 6D all have the same issues. I've experimented with various modelling bulbs with other colour spectrums. Some definitely improved the AF, but not enough. Ultimately, CDAF is my workaround. It seems to always be 100% accurate and -luckily for me- my studio work doesn't require the speed of the much faster PDAF.
02-26-2013, 02:39 AM   #1137
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QuoteOriginally posted by Clavius Quote
I stated that it felt like maybe 2 seconds. Goes for both my K5's with almost the latest firmware. (I ignored the one for the 560mm lens improvements.) You're now confirming that it's just short of 3. Are you seriously debating fractions of a second? Lets round it up: 3 seconds, still poorly compared to how long a 5D lasts.
You said "one, maybe 2 seconds". That sounds like ~1.5 seconds to me, so you were off by ~100%.
02-26-2013, 03:15 AM   #1138
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It's 22 RAW frames at 6.5fps - real life continuous shooting.
Almost 4 seconds worth. How much continuous shooting buffer is needed in real life shooting?
If a photographer cannot get one keeper from over 3 seconds of 6.5fps shooting, then the issue is with the photographer rather than the camera.
02-26-2013, 03:17 AM   #1139
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QuoteOriginally posted by Ash Quote
If a photographer cannot get one keeper from over 3 seconds of 6.5fps shooting, then the issue is with the photographer rather than the camera.

+1 I couldn't agree more...
02-26-2013, 04:20 AM   #1140
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I guess if you need more than 3 seconds to catch a moment, you'd might as well buy a camcorder.

Last edited by deus ursus; 02-26-2013 at 04:22 AM. Reason: correcting grammar (added a 'd :) )
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