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02-12-2007, 09:34 AM   #16
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The noise clean up solution

Hi,
I use Silkypix which includes noise reduction. I also use Bibble which includes Noise Ninja. The problem is that while these programs work mostly wonders, where the subject matter is dark (ie, people are wearing dark clothes, or have dark hair, or are standing infront of a dark wall), the extremity of the noise and banding is visible, even in 4x6 prints (resulting from a fully color managed work-flow). And I don't just mean the color black. It is visible in anything darker than a medium shade and it effects all colors, red, brown, gray, etc.

I have come to grips with the high ISO noise/banding of the K10D since it is only ugliest under the circumstances described above. But my solution was to learn how to properly use flash. This bug renders my solution useless as it results in the same problematic symptoms.

As far as using manual, I have no desire to spend that much time worrying about the camera. I want to focus on the subject, exposure, and composition. That to me says that 99% of the time, I should only have to worry about aperture and/or ev compensation. Once I set the auto ISO range and choose P mode (MFT prgram line), I should rarely have to think about it.

02-12-2007, 09:36 AM   #17
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Spoke to Pentax

Just spoke with Pentax. They agree that the K10D should be adjusting ISO when the flash is used. The only way to get it into the firmware fix pipeline is to request it (which I have done via online web support form). They said the more people make the request, the more likely a fix. So, if you are experiencing this issue, please let them know and maybe it will be fixed in the next firmware update.
02-12-2007, 09:44 AM   #18
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Call me silly but I never knew there was such a form. (Maybe something that should be added as a sticky somewhere Adam)

Did you mean this one Pentax Imaging

and if so we have what 1200+ users how many do you think will make a dent in getting any kind of change?
02-12-2007, 09:49 AM   #19
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the auto iso thing seems a bit problematic.. the k100 has the ev related bug the k10 seems to have a flash related bug..

trog

02-12-2007, 09:54 AM   #20
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QuoteOriginally posted by loganross Quote
But this appears to be a bug which is very illogical, but can be easily fixed.
There are many different potential choices for automatic functions, each has its pros and cons. I just can't see how you can say it's a bug. You set the high ISO settings, you told the camera that it's OK to use that settings, and now you are not happy because the camera chose a settings you have chosen yourself?

As I said before, there are many advantages of High ISO in flash shots, at the expense of noise. You just have to tell the camera which ISO not to use - isn't this how it is supposed to work?

QuoteQuote:
BTW, yes I could use Sv mode or some other mode, but why would I want to.
Why? Because you want the camera to behave in a specific way. It cannot read your mind, if you want low ISO with flash, you have to set it. For me, I use low ISO when the flash is the main illumination and it is within the flash range. I also use high ISO when I want to allow more ambient light (when no tripod available) so that I won't get a pitch black background.

QuoteQuote:
It would seem to me that ISO is the easiest of the variables for the camera to determine.
Not at all, the camera does not know your priorities. In your case, you want low noise, but not all users have the same priorities.

QuoteQuote:
Moreover, I like P mode coupled with the MTF program line.
I believe the same program line would be use in Sv mode or other modes as well.

QuoteQuote:
"On my DS/DL, they're also on auto iso (200-3200) and when I take a similar shots with the flash up, they take it at iso-200."
There is a difference, in K10D, you can set the Auto ISO range freely. So the camera would assume you would set it at your specified range.
02-12-2007, 09:54 AM   #21
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Pentax imaging web support form link

Pentax email webform
02-12-2007, 10:32 AM   #22
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I think you misunderstood my points. The purpose of increasing sensitivity is to increase the ability to capture light that is otherwise too low to make for a proper exposure (at the expense of noise). The purpose of the flash is to create more light. Thus, they are alternatives. One option is to create more light. The other option is to compensate for the inability to create more light (or to satisfy the desire to use existing and otherwise insufficient light). While under certain circumstances both may be required (such as when even the flash does not provide sufficient light), I would think that having elected to use the flash, which is done manually on the K10D, would indicate a preference of creating more light first, and increasing sensitivity second and only when required.

I am not talking about shots from 20 feet away or shots in complete darkness. I am talking about shots that are 5-7 feet away in late afternoon (ie, dim lighting but not really low lighting). This is hardly beyond the capability of the K10D's onboard flash. In fact most of the time I have to dial in negative flash compensation to prevent over exposure. Yet I am still stuck with an image full of noise and banding.

Please again, I know I can change the modes and adjust things manually (like reducing the auto ISO range from 800 to 400), but doesn't that defeat the purpose of AUTO? Moreover, there are many instances where ISO 800 is useful and not so destructive (such as reasonably well lit available light shots).

I am not picking on Pentax. But every camera I have owned (pentax or not, dSLR or PS) gets the Auto ISO - Flash relationship right. Why shouldn't the K10D? My purpose of posting is that if enough people are effected by the issue and notify Pentax, it should be relatively easy to resolve in a firmware update.
02-12-2007, 11:14 AM   #23
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sounds like bug to me loganross.. but there will be many that will try and rationalize it away..

auto iso is about permitting the camera to go up to a user fixed maximum point when it has to.. if it boosts the iso/noise when it dosnt have to there isnt much point in having it..

or to put it another way.. lowering the iso/noise when it can do.. either way its what the "auto" part means..

trog

02-12-2007, 11:48 AM   #24
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Well, I think we just have to agree to disagree here.... we simply have different expectation of what Auto means and how it should behave.

As Auto ISO range is under own total control, I can't see why choosing a high ISO is defeating the purpose of Auto. And K10D is the easiest camera to change ISO.

Pentax has made conscious effort to allow as much ambient light as possible in flash photo by varying the shutter speed according to the focal length (not all cameras are like this). That's the reason why I think it is the same design philosophy in the ISO behavior.

The Auto ISO does have a bug during program shift; but I really do not feel that this is a bug.
02-12-2007, 11:51 AM   #25
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QuoteOriginally posted by trog100 Quote
auto iso is about permitting the camera to go up to a user fixed maximum point when it has to.. if it boosts the iso/noise when it dosnt have to there isnt much point in having it..
or to put it another way.. lowering the iso/noise when it can do.. either way its what the "auto" part means..
Yes, but you can't have both lower noise and better ambient/flash balance. This is a choice the programmer has to decide. And it just so happens you prefer the former, and the programmer has chosen the latter. And since Auto ISO range is under you total control, you can easily cater it to your own needs.
02-12-2007, 12:37 PM   #26
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i think its a "bug".. just like i think the stupid way the k100 wrecks its neat auto iso feature when any plus or minus ev is used is a "bug"..

the k10 seems to have fixed this "bug" but introduced another one..

boosting the iso to noisy levels has been used by the odd "point and shoot" in the past to enable the makers to claim a better flash range than the camera actually has..

i have an otherwise neat little 10 x zoom jobby that does it.. it simply means the camera is unusable with flash.. its intended so in that sense its not a bug.. but it spoils an otherwise nice little camera..

the bottom line being if an "auto" feature has weird habits it becomes unusable.. i find myself manually setting the iso levels in my k100 more and more cos i cant trust the auto iso feature..

last week i put in a plus 1 ev for some long range snow shots.. the result a whole bunch of ruined pics cos the silly camera dropped its iso from the normal iso 800 it would be useing without the ev set to iso 200..

mind u i expect things not to work in a sensible fashion.. so i am never surprized when i find they dont..

trog
02-12-2007, 01:18 PM   #27
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This is an issue that needs to be adressed

QuoteOriginally posted by trog100 Quote
sounds like bug to me loganross.. but there will be many that will try and rationalize it away..

auto iso is about permitting the camera to go up to a user fixed maximum point when it has to.. if it boosts the iso/noise when it dosnt have to there isnt much point in having it..

or to put it another way.. lowering the iso/noise when it can do.. either way its what the "auto" part means..

trog
My rationalization is sound, sorry to all whom I offend, but.. the on board flash has issues. I brought this up in the P.A. forum 5 weeks ago and it was extensively commented on with most blaming the user, most well intended but missing the point.

As I stated then, and have not changed my opinion, in Full Auto Mode you should be able to take quick candid shots with the flash with any modern camera sold as a prosumer unit;

Since I have had my K10D, my first true digital SLR, I have been noticing a weirdness that really bugs me.

The onboard flash is not consistant in it's exposure, and I am losing 20-50% of candid shots due to under or over exposure of the subject, usually under.

In the past I have used fill flash for bright backlit portraits a lot, with excellent results, all my Sony higher end cameras (707, 717 828, R1) and prior Nikon F401s worked perfectly using this technique, but the Pentax K10D seems to have a problem with it. My son has a Nikon D70s, no problem, a friend with Canon Digital Rebel, no problem (of course they have other issues, )

I have tried various programs, P, Green (A) mode etc, and various flash programs, and metering settings.

I have tried shots with Center Weighted Average, Flash on Auto, Spot Metering on Auto, Flash Compensation with distances of .2 to 3.5-meters, with various Pentax and Sigma lenses. Sometimes it works, sometimes not, mostly not.

It seems that if there is ANY bright background in the frame, or reflection from metal, chrome or even eye glass frames, the flash figures it is not needed and shuts down to a very dim output, or if forced cranks up the ISO or both.

Sorry, if I wanted a full manual camera I would have selected other options. I selected the K10D because of it's flexibility and great options between Auto and Manual, and the on board flash is simply not acceptable.

Strangely, since purchasing an AF-360gz Pentax Flash, the problem has mostly disappeared, now I can truly attribute it to my technique. I have taken some stunning shots at full night, backlit, reflective etc with this P-TTL flash that would not have worked with the onboard flash. This however is not the flash option you want to push into faces at indoor gatherings

So, as I said at the start, my rationalization is I feel, sound. It is based on personal experience (I got my first Kodak Box Brownie Starflash in 1956 and have not been without a camera in my hand since) and testing, and I hope Pentax is listening as this is my only major complaint, but in my opinion a major one. When I go to shoot candid at parties and indoor functions, I take my Sony F717, it never misses a flash shot.. focusing? well it is not a DSLR!!

Please Pentax, this is NOT a Rant, I just want a good onboard flash.
02-12-2007, 01:36 PM   #28
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nosnoop,

I am not sure where you are getting the notion of flash/ambient light balance. According to Pentax, the flash does not vary intensity unless manually done by the user with flash comp. Can you provide your basis for this determination?

Moreover, to your point.....where noise is an issue at high ISO, why would the camera raise ISO when it s unnecessary to do so because the flash provides sufficient light.
02-12-2007, 08:33 PM   #29
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QuoteOriginally posted by loganross Quote
was wondering if anybody noticed that the K10D seems to max out the ISO (when in auto ISO), even when you are using the flash.

I have my auto ISO range set to 100-800. I understand why ISO would be high for an available light photo, but why for a flash photo? Its almost as if the auto-ISO algorithm does not take into account use of the flash.

The problem is the high ISO introduces noise in the picture which I don't want and which I would think is unnecessary.

Any help or opinions are welcome.

hi logan

next time you use your flash in a darker spot, please look at your histogram on the camera preview. If the hump is all to the left like mine, you might be getting the same problem I am having. first try a shot with the lens at its smallest zoom, then compare the same shot made at max zoom of your lens.
If the max zoom appears darker on the histogram then the shot with the least zoom, it sounds like the zoom of the flash is not working with the zoom of the lens

hope this helps

please see my post https://www.pentaxforums.com/forums/pentax-dslr-discussion/3228-wondering-would-better.html
on my last response to this post, I described the problem in details
02-13-2007, 12:25 AM   #30
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QuoteOriginally posted by loganross Quote
I am not sure where you are getting the notion of flash/ambient light balance. According to Pentax, the flash does not vary intensity unless manually done by the user with flash comp. Can you provide your basis for this determination?
Hmmm.... did you read my earlier reply to you?
https://www.pentaxforums.com/forums/25997-post7.html

And I am not sure about your statement "flash does not vary intensity unless manually done..." This of course is not true. The whole point of P-TTL is to use a pre-flash and meter the whole scene - both pre-flash and ambient light. And the camera could distinguish between low light night scene or bright daylight fill flash, and adjust the flash output accordingly. And if you have a wide angle zoom, you can change the zoom and see how the shutter speed would go way down to allow as much ambient light as possible.

QuoteQuote:
Moreover, to your point.....where noise is an issue at high ISO, why would the camera raise ISO when it s unnecessary to do so because the flash provides sufficient light.
The flash would provide sufficient light to illuminate the subject, but not the background. The background would be pitch black if a high ISO and a high shutter speed are chosen. Using high ISO and as slow a hand holdable shutter speed as possible would brighten up the background considerably and give you a better flash shot. This can be helped further using Slow Speed Sync if you have a tripod.

Other advantages of high ISO is much better flash range (built-in flash range is very limited), and reduced flash output to improve battery life.
If you are concerned about high ISO noise, just set a lower Auto ISO range.
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