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illdefined · 08-25-2010, 10:42 AM

Originally posted by Agnostic

Noise comparison impressions from the images in the imaging resource comparometer:

A560 is at least one stop better than the A33 at 1600 and 3200 ISO.

A55 is about half a stop or less worse than the A560 at 1600 and 3200 ISO.

The KX looks similar to the A560 at 1600 and 3200 ISO.

The Sony images look consistently less sharp than those from the KX, looks like jpg smoothing to remove some noise but it could be the lens.

From that I'd say that if the difference for the A560 and A33 hold for the A55 and the K-5 the K-5 should be able to reach Kx high ISO levels or even surpass them slightly by about half a stop max at high ISO.

The A55 also has a much, much cleaner blue channel than the K-7 at all ISO settings. Good news for landscape shooters who like b&w.

Now the wait is for Raw shots!

i'm actually looking forward to a day when most cameras share and standardize on common sensors. then, like the old film days, cameras and camera-makers will be judged only by their glass, service and the individual features and ergonomics of their bodies.

and · 08-25-2010, 10:50 AM

The new sensor has 16mpix, even if the manufacturers improve noise somewhat in each generation they normally eat it up by increasing the amount of mpix. For those who want fantastic iso noise, the best camera is the D3s and that has only 12mpix on a ff sensor, if they used all the latest innovations and made a new 10mpix sensor then presumably it would have quite good noise performance and could also deliver more fps. Already saw in the negatives on the dpr review of the new sony that there was NR killing details over iso 400. I ge the impression a lot of the new cameras has just worse noise performance but better NR software in camera, but if that is the case I can run strong NR on my k7 shots today to get good iso performance.

Agnostic · 08-25-2010, 10:56 AM

Originally posted by wowtip

...or to use f1.4 lenses wide open, without flash in sunshine without ND filters, for really thin DOF.

I wouldn't want to use the FA 50/1.4 wide open unless you want really soft shots.

Originally posted by and

The new sensor has 16mpix, even if the manufacturers improve noise somewhat in each generation they normally eat it up by increasing the amount of mpix. For those who want fantastic iso noise, the best camera is the 3Ds and that has only 12mpix on a ff sensor, if they used all the latest innovations and made a new 10mpix sensor then presumably it would have quite good noise performance and could also deliver more fps. Already saw in the negatives on the dpr review of the new sony that there was NR killing details over iso 400. I ge the impression a lot of the new cameras has just worse noise performance but better NR software in camera, but if that is the case I can run strong NR on my k7 shots today to get good iso performance.

Agreed. I wouldn't mind a 12mp sensor in a good semi-pro body if it had improved dynamic range and signal/noise ratios. I still don't understand why no other camera manufacturer has followed up on the Fuji S5. that had a dynamic range of 13.5 like the S3 which was introduced 6 years ago. The only camera that has surpassed that since is the Nikon D3x with 13.7 and that came 4 years after the Fuji S3. They keep adding extra features and upping the MP count but dynamic range has had way to little attention. In fact it decreased from the K20D to the K-7.

Ishpuini · 08-25-2010, 01:50 PM

Originally posted by Steelski

How am I wrong, only 70% of the light gets through, if it was 50% it would be half the light. AKA 1 stop. 70% of light getting through is a loss of 3/5ths of a stop, which is larger than 1/2. It is 60% of a stop light fall off.
I am not wrong. Its just a different way of stating it.
I could state that its more than a 50% of a stop light fall off. which would also be right. Roughly 1/2 a stop is also right, although less accurate.

How could you be wrong? Because your reasoning assumes a linear relationship between % of light loss and the same in stops/Ev. The relation is not linear, its exponential.

30% loss is exactly 0,514573 Ev. 1/2Ev would be 0,5 and 3/5Ev would be 0,6. You tell me which is closer to 0,514573, 0,5 or 0,6, and as such more accurate...

It's not a major issue however. And in practice it's the images that matter.

Wim

glanglois · 08-25-2010, 02:33 PM

Originally posted by Ishpuini

How could you be wrong? Because your reasoning assumes a linear relationship between % of light loss and the same in stops/Ev. The relation is not linear, its exponential.

<snip>

Wim

That's when I get for retiring my K&E slide rule.

I forgot I should be doing this with logs.

In general, though, I solved my computation crisis by assuming that all values within a given order of magnitude are about the same. Saves a lot of time but tends to aggravate the IRS.

**jpzk** · 08-25-2010, 04:06 PM

Just out of curiosity, why am I seeing some "other forums" mentioning that the K5 would be an "in-between" camera, i.e.: between the K7 and K5?

JP

ewalk · 08-25-2010, 04:11 PM

Originally posted by jpzk

Just out of curiosity, why am I seeing some "other forums" mentioning that the K5 would be an "in-between" camera, i.e.: between the K7 and K5?

JP

Old rumors? I'm pretty sure the K-5 name floated around as the model under the K-7 until the K-r model/rumor came up.

**jpzk** · 08-25-2010, 04:21 PM

Originally posted by ewalk

Old rumors? I'm pretty sure the K-5 name floated around as the model under the K-7 until the K-r model/rumor came up.

That figures.
I recall having asked why Pentax would call an upgraded camera with a "number" lower than the present "flagship" number (i.e.: from K7, I was probably expecting a "K8" or something like that) and someone here at this forum put me back in my place!

Thanks for the response.

JP

**Digitalis** · 08-25-2010, 04:49 PM

" wouldn't want to use the FA 50/1.4 wide open unless you want really soft shots."

I use my Pentax 50mm f/1.2 wide open for studio portraiture. That lens performs extremely well in that arena.

zackspeed · 08-25-2010, 05:02 PM

Originally posted by jpzk

Just out of curiosity, why am I seeing some "other forums" mentioning that the K5 would be an "in-between" camera, i.e.: between the K7 and K5?

JP

K-5
K-7
K-r
K-x

gary1952 · 08-25-2010, 09:21 PM

If it handles noise at or above the K-x.... I'll be on the next train to K-5 ville

ogl · 08-25-2010, 10:14 PM

Originally posted by Netsoft

OGL has been quite reliable with his rumors. I personally believed he's the unofficial pentax news release

I don't think so....

How soon - not later, September, 10-15. But it's not 100% true info.
K-R will be first, K-5 is on September, 20.

rvannatta · 08-25-2010, 10:51 PM

Originally posted by ogl

I don't think so....

How soon - not later, September, 10-15. But it's not 100% true info.
K-R will be first, K-5 is on September, 20.

some other sites have the release announcments of another brand today with 18mp and apparently a lower price. If the real high ISO numbers of this product work really well there will be value here but otherwise it will be hard to see
this product flying off the shelves at a price higher than than the brard c model 60D announced today. I love pentax---hope they have something up their sleeve.

Supernaut · 08-25-2010, 11:41 PM

Originally posted by zackspeed

K-5
K-7
K-r
K-x

That's plenty of model name range for a more pro K-3 and K-1 then

Steelski · 08-25-2010, 11:49 PM

Originally posted by Ishpuini

How could you be wrong? Because your reasoning assumes a linear relationship between % of light loss and the same in stops/Ev. The relation is not linear, its exponential.

30% loss is exactly 0,514573 Ev. 1/2Ev would be 0,5 and 3/5Ev would be 0,6. You tell me which is closer to 0,514573, 0,5 or 0,6, and as such more accurate...

It's not a major issue however. And in practice it's the images that matter.

Wim

Please explain your calculation. I can concede if I am wrong. I would like to learn.

08-25-2010, 10:50 AM	#347
and Veteran Member Join Date: Mar 2007 Photos: Gallery Posts: 2,476	The new sensor has 16mpix, even if the manufacturers improve noise somewhat in each generation they normally eat it up by increasing the amount of mpix. For those who want fantastic iso noise, the best camera is the D3s and that has only 12mpix on a ff sensor, if they used all the latest innovations and made a new 10mpix sensor then presumably it would have quite good noise performance and could also deliver more fps. Already saw in the negatives on the dpr review of the new sony that there was NR killing details over iso 400. I ge the impression a lot of the new cameras has just worse noise performance but better NR software in camera, but if that is the case I can run strong NR on my k7 shots today to get good iso performance. Last edited by and; 08-25-2010 at 02:15 PM.

08-25-2010, 10:56 AM	#348
Agnostic Veteran Member Join Date: Mar 2009 Location: Netherlands Photos: Gallery \| Albums Posts: 414	Originally posted by wowtip ...or to use f1.4 lenses wide open, without flash in sunshine without ND filters, for really thin DOF. I wouldn't want to use the FA 50/1.4 wide open unless you want really soft shots. Originally posted by and The new sensor has 16mpix, even if the manufacturers improve noise somewhat in each generation they normally eat it up by increasing the amount of mpix. For those who want fantastic iso noise, the best camera is the 3Ds and that has only 12mpix on a ff sensor, if they used all the latest innovations and made a new 10mpix sensor then presumably it would have quite good noise performance and could also deliver more fps. Already saw in the negatives on the dpr review of the new sony that there was NR killing details over iso 400. I ge the impression a lot of the new cameras has just worse noise performance but better NR software in camera, but if that is the case I can run strong NR on my k7 shots today to get good iso performance. Agreed. I wouldn't mind a 12mp sensor in a good semi-pro body if it had improved dynamic range and signal/noise ratios. I still don't understand why no other camera manufacturer has followed up on the Fuji S5. that had a dynamic range of 13.5 like the S3 which was introduced 6 years ago. The only camera that has surpassed that since is the Nikon D3x with 13.7 and that came 4 years after the Fuji S3. They keep adding extra features and upping the MP count but dynamic range has had way to little attention. In fact it decreased from the K20D to the K-7. Last edited by Agnostic; 08-25-2010 at 11:07 AM.

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08-25-2010, 10:42 AM	#346
illdefined Veteran Member Join Date: Jan 2009 Location: NYC Posts: 929	Originally posted by Agnostic Noise comparison impressions from the images in the imaging resource comparometer: A560 is at least one stop better than the A33 at 1600 and 3200 ISO. A55 is about half a stop or less worse than the A560 at 1600 and 3200 ISO. The KX looks similar to the A560 at 1600 and 3200 ISO. The Sony images look consistently less sharp than those from the KX, looks like jpg smoothing to remove some noise but it could be the lens. From that I'd say that if the difference for the A560 and A33 hold for the A55 and the K-5 the K-5 should be able to reach Kx high ISO levels or even surpass them slightly by about half a stop max at high ISO. The A55 also has a much, much cleaner blue channel than the K-7 at all ISO settings. Good news for landscape shooters who like b&w. Now the wait is for Raw shots! i'm actually looking forward to a day when most cameras share and standardize on common sensors. then, like the old film days, cameras and camera-makers will be judged only by their glass, service and the individual features and ergonomics of their bodies.

08-25-2010, 01:50 PM	#349
Ishpuini Veteran Member Join Date: Sep 2006 Location: Antwerp, Belgium Photos: Gallery Posts: 1,727	Originally posted by Steelski How am I wrong, only 70% of the light gets through, if it was 50% it would be half the light. AKA 1 stop. 70% of light getting through is a loss of 3/5ths of a stop, which is larger than 1/2. It is 60% of a stop light fall off. I am not wrong. Its just a different way of stating it. I could state that its more than a 50% of a stop light fall off. which would also be right. Roughly 1/2 a stop is also right, although less accurate. How could you be wrong? Because your reasoning assumes a linear relationship between % of light loss and the same in stops/Ev. The relation is not linear, its exponential. 30% loss is exactly 0,514573 Ev. 1/2Ev would be 0,5 and 3/5Ev would be 0,6. You tell me which is closer to 0,514573, 0,5 or 0,6, and as such more accurate... It's not a major issue however. And in practice it's the images that matter. Wim

08-25-2010, 02:33 PM	#350
glanglois Veteran Member Join Date: Aug 2007 Location: Madison, Wis., USA Posts: 1,506	Originally posted by Ishpuini How could you be wrong? Because your reasoning assumes a linear relationship between % of light loss and the same in stops/Ev. The relation is not linear, its exponential. <snip> Wim That's when I get for retiring my K&E slide rule. I forgot I should be doing this with logs. In general, though, I solved my computation crisis by assuming that all values within a given order of magnitude are about the same. Saves a lot of time but tends to aggravate the IRS.

08-25-2010, 04:06 PM	#351
jpzk Site Supporter Join Date: Jan 2009 Location: Québec Photos: Gallery \| Albums Posts: 8,251	Just out of curiosity, why am I seeing some "other forums" mentioning that the K5 would be an "in-between" camera, i.e.: between the K7 and K5? JP

08-25-2010, 04:11 PM	#352
ewalk Veteran Member Join Date: Sep 2008 Location: Texas Posts: 316	Originally posted by jpzk Just out of curiosity, why am I seeing some "other forums" mentioning that the K5 would be an "in-between" camera, i.e.: between the K7 and K5? JP Old rumors? I'm pretty sure the K-5 name floated around as the model under the K-7 until the K-r model/rumor came up.

08-25-2010, 04:21 PM	#353
jpzk Site Supporter Join Date: Jan 2009 Location: Québec Photos: Gallery \| Albums Posts: 8,251	Originally posted by ewalk Old rumors? I'm pretty sure the K-5 name floated around as the model under the K-7 until the K-r model/rumor came up. That figures. I recall having asked why Pentax would call an upgraded camera with a "number" lower than the present "flagship" number (i.e.: from K7, I was probably expecting a "K8" or something like that) and someone here at this forum put me back in my place! Thanks for the response. JP

08-25-2010, 04:49 PM	#354
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,694	" wouldn't want to use the FA 50/1.4 wide open unless you want really soft shots." I use my Pentax 50mm f/1.2 wide open for studio portraiture. That lens performs extremely well in that arena.

08-25-2010, 05:02 PM	#355
zackspeed Veteran Member Join Date: Mar 2010 Posts: 527	Originally posted by jpzk Just out of curiosity, why am I seeing some "other forums" mentioning that the K5 would be an "in-between" camera, i.e.: between the K7 and K5? JP K-5 K-7 K-r K-x

08-25-2010, 09:21 PM	#356
gary1952 Inactive Account Join Date: Feb 2010 Location: thailand Posts: 45	If it handles noise at or above the K-x.... I'll be on the next train to K-5 ville

08-25-2010, 10:14 PM	#357
ogl Banned Join Date: Dec 2007 Location: Sankt Peterburg Photos: Gallery \| Albums Posts: 8,382 Original Poster	Originally posted by Netsoft OGL has been quite reliable with his rumors. I personally believed he's the unofficial pentax news release I don't think so.... How soon - not later, September, 10-15. But it's not 100% true info. K-R will be first, K-5 is on September, 20.

08-25-2010, 10:51 PM	#358
rvannatta Pentaxian Join Date: Aug 2007 Location: Apiary, Oregon Photos: Gallery Posts: 1,181	Originally posted by ogl I don't think so.... How soon - not later, September, 10-15. But it's not 100% true info. K-R will be first, K-5 is on September, 20. some other sites have the release announcments of another brand today with 18mp and apparently a lower price. If the real high ISO numbers of this product work really well there will be value here but otherwise it will be hard to see this product flying off the shelves at a price higher than than the brard c model 60D announced today. I love pentax---hope they have something up their sleeve.

08-25-2010, 11:41 PM	#359
Supernaut Veteran Member Join Date: Sep 2008 Location: West Coast , Sweden Posts: 467	Originally posted by zackspeed K-5 K-7 K-r K-x That's plenty of model name range for a more pro K-3 and K-1 then

08-25-2010, 11:49 PM	#360
Steelski Veteran Member Join Date: Jan 2008 Location: Varna Posts: 470	Originally posted by Ishpuini How could you be wrong? Because your reasoning assumes a linear relationship between % of light loss and the same in stops/Ev. The relation is not linear, its exponential. 30% loss is exactly 0,514573 Ev. 1/2Ev would be 0,5 and 3/5Ev would be 0,6. You tell me which is closer to 0,514573, 0,5 or 0,6, and as such more accurate... It's not a major issue however. And in practice it's the images that matter. Wim Please explain your calculation. I can concede if I am wrong. I would like to learn.

Brief info about K-5 and KR

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