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06-25-2010, 04:09 PM   #61
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Those last few shots are great! Nothing wrong with the quality the kit lens, although of course, you'd have managed faster shutter speeds and therefore more keepers with a faster lens.

BTW, as for circular breathing, I worked with a few guys who do this on trumpet. It's actually easier on trumpet than on saxophone, I think, because there is more backpressure to help control the outward flow of air while inhaling with the nose.

06-25-2010, 05:18 PM   #62
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QuoteOriginally posted by Marc Sabatella Quote
Those last few shots are great! Nothing wrong with the quality the kit lens, although of course, you'd have managed faster shutter speeds and therefore more keepers with a faster lens.
Thank you.

Yes, can't disagree -
however the kit lens max aperture is f/3.5 at 18mm which I use a lot -
I don't know of many other 18mm lenses prime or zoom that does better than f/2.8 - which is 2/3 stop faster so I go from the minimum I can handhold at 1/4sec to maybe 1/6sec? I am not too sure if I'd really get many more keepers at 1/6sec?

The only Pentax made lens that covers 18mm and has a wider max aperture is the 16-50 DA* at over $740 it's more than my K-x and lenses combined - hard to justify for a marginal gain in shutter speed. I could have just cranked the ISO up to ISO8000 to mitigate that.

I do realize obviously the 16-50mm will maintain f/2.8 throughout the focal length range - so at its max focal length of 50mm it would be doing better by almost 2 stops over the 18-55mm kit zoom and that would be worthwhile - however I probably would have changed to the 50-200 kit zoom to get f/4 at 50mm at least mitigating 1 stop.......

I may think about the Sigma 18-50mm f/2.8 - but even that is over $400 - and covers only the range I already have

I may shoot a lot but it is still a hobby to me - albeit an obsessive one.

If I was having to make a living from my photos (I'd be poor) but I may have different attitude toward more expensive glass.

QuoteOriginally posted by Marc Sabatella Quote
BTW, as for circular breathing, I worked with a few guys who do this on trumpet. It's actually easier on trumpet than on saxophone, I think, because there is more backpressure to help control the outward flow of air while inhaling with the nose.
Thanks Marc - I've only known about circular breathing by reed players - initially mostly oboe where it's also called double-breathing - and in jazz the sax.

First time I noticed on a brass instrument was at the Atlanta Jazz Fest this year when Trombone Shorty did it on a trumpet

he was doing it in this shot -
- it was pretty obvious he had to be doing circular breathing -
otherwise there's be a guy pumping him up from behind
and I didn't see any hoses attached!

Thanks Marc - always a pleasure to hear from you.
06-25-2010, 11:51 PM   #63
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QuoteOriginally posted by UnknownVT Quote
however the kit lens max aperture is f/3.5 at 18mm which I use a lot -
I don't know of many other 18mm lenses prime or zoom that does better than f/2.8
Indeed, the kit lens makes a very fine DA18/3.5! If it really had been built to do that and that only, and was correspondingly smaller, I'd probably never have bothered with the DA15.

QuoteQuote:
Thanks Marc - I've only known about circular breathing by reed players - initially mostly oboe where it's also called double-breathing - and in jazz the sax.
Oboe, now I hadn't thought of that. It too involves quite a bit of backpressure, I believe. And now that you mention it, one of the reed players I know who does use circular breathing is Paul McCandless, who plays oboe and English horn in addition to saxophones & bass clarinet.
06-26-2010, 12:46 AM   #64
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QuoteOriginally posted by Marc Sabatella Quote
one of the reed players I know who does use circular breathing is Paul McCandless, who plays oboe and English horn in addition to saxophones & bass clarinet.
Paul McCandless - now that conjures up the classic ensemble - Oregon -
with Ralph Towner, guitar and Colin Walcott, tablas -

Also the name I first knew of the English horn was the cor'Anglais (which is "English horn" in French) -

In classical music apparently these double reed instruments have notoriously difficult embouchure, and I thought part of the reason double- or circular breathing developed was not just for long notes or runs, but so they wouldn't have to lose their embouchure, is that true?

I was a fan (and friend) of the late Rahsaan Roland Kirk - who I believe was in the Guinness Book of world records for holding the longest note on the sax - through circular breathing.


Last edited by UnknownVT; 06-26-2010 at 07:26 AM.
06-26-2010, 09:12 AM   #65
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QuoteOriginally posted by UnknownVT Quote
In classical music apparently these double reed instruments have notoriously difficult embouchure, and I thought part of the reason double- or circular breathing developed was not just for long notes or runs, but so they wouldn't have to lose their embouchure, is that true?
Could be; I hadn't heard that before. Only instrument I know where circular breathing is really part of the generally accepted technique as opposed to a rare thing employed by a select few is didgeridoo.

QuoteQuote:
I was a fan (and friend) of the late Rahsaan Roland Kirk - who I believe was in the Guinness Book of world records for holding the longest note on the sax - through circular breathing.
Now that is cool (having known Rahsaan). I hate to break it to you, though, but that record was infamously broken a few years back by a certain "pop star" soprano saxophonist with the single letter for a last name...

Not with a K-x, so off-topic in that sense, but at least getting back to photography, here are a few relevant pictures.

1) Hugh Ragin - the first guy I ever heard do circular breathing. This is a shot I've posted before as one of the slowest shutter speeds I've successfully used in concert photography (1/6") - a testament to Hugh's relaxed technique more than anything:


2) Paul McCandless on the English Horn (indeed, neither English nor a horn, technically speaking):


3) Didgeridoo player on the street:

Last edited by Marc Sabatella; 06-26-2010 at 09:22 AM.
06-26-2010, 10:15 AM   #66
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QuoteOriginally posted by Marc Sabatella Quote
Now that is cool (having known Rahsaan). I hate to break it to you, though, but that record was infamously broken a few years back by a certain "pop star" soprano saxophonist with the single letter for a last name...
Yes, I have pics of him on the K-x ......

Well... OK it's Kenny Gradney of Little Feat -
whom I've kiddingly nicknamed Kenny G.
he does take it well, and always responds by shaking me warmly....
by the throat!

Yeah, I read that circular breathing is intrinsic in quite a few instruments including the didgeridoo

My shot of Rahsaan from 1972 -
so it is also OT -
as it could not possibly be the K-x.
It's a Zenith-B manual everything SLR (and I mean manual everything - there isn't even auto actuation of aperture diaphragm for lenses - no meter - I had to use a separate handheld meter) Meyer Orestor 135mm f/2.8 pre-set diaphragm lens - BUT Pentax 42mm screw mount - Ilford FP4 developed in Paterson's Acuspecial - rated at ISO200, f/4, 1/30 - printed on IlfoBrom Gr.3
(oh, and SunPak manual flash tiny weak thing held at arm's length)

Last edited by UnknownVT; 06-26-2010 at 11:30 AM.
06-28-2010, 11:53 AM   #67
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First let me state quite clearly that the Pentax K-x AWB (Auto White Balance) works really well for me for most of my shooting - it is definitely and noticeably better than my K100D - (in fact I would almost go as far to say "miraculously" better).

However once in a while I have found some difficulties under what can only be described as more extreme conditions where even manual white balance probably would not help.

At first I thought it may be attributable to modern LED stage lighting where the LEDs used to make up any color are just Red, Green and Blue LEDs - which have very narrow wavebands - thus giving very peaky spectrum without any real in between color content see my Post #44 (link) above - and the whole thread - Modern LED Stage Lighting & photography problems)

However with more usage I realized it's not just narrow band LEDs - although they do very much aggravate the situation further and they are becoming more and more prevalent - so one just can no longer avoid them - but it appears to be any strongly mono-colored lighting - eg: red gel filtered tungsten light, or worse magenta gel filtered tungsten light.

I think this may also be an intrinsic difficulty with any digital camera using the Bayer matrix sensor - which is just about all the commonly commercially available cameras..... for a really good explanation please see post #341 by Canuke over at 4Sevens' CPF MarketPlace.

It appears that our dSLRs (and almost any digicam) cannot capture all that we can see - no matter how well the color accuracy is rated - as that is analyzed by computer from digital images of a Macbeth chart - and reference itself is a capture digital image from guess what? a digicam so that's almost a self-fulfilling benchmark?

Anyway deep reds are not captured by Bayer matrix digicams and rendered somewhat orange and processing can help "fake" it sometimes by balancing out (ie: having less of) the opposite/complementary color.

I have found that the K-x does have difficulties with more extreme colored lighting -

here are some examples and compared directly with my Canon G10 compact which seems to cope somewhat better with the extreme lighting
(all photos no PP other than resize and level 1 sharpening -
all should have EXIF data attached -
caveat: PhotoBucket can sometimes mysteriously drop metadata)

First mainly red gel tungsten lighting to show the problem is not isolated to LEDs -

K-x No Flash


Canon G10 No Flash

similar rendition eg: the three people at the front in more normal "white" lighting -
but notice how the G10 image seems to have more separation in the red area - thus showing more detail - eg: look at the bassist's face - it's not just exposure - but the difference in the way the two cameras do their respective white balance.

I have found sometimes using weak flash can throw some "white" light onto the scene which helps mitigate some of the problems with strong mono-color lighting - same scene with weak flash -

K-x with slow-sync flash (-1 stop flash compensation)

notice that the flash does help to improve the balance and lack of separation...

Canon G10 with slow-sync flash (-1 2/3 stop flash compensation) -

the G10 is just "better" in rendition - but at least it's not that dramatic a difference - although the K-x image still has mushy details in the vocalist's and bassist's faces - this is definitely due to JPG compression - but the Canon G10 images do not have this problem and they are smaller files and have had exactly the same degree of JPG compression.

OK now for some more radical LED stage lighting -

K-x No flash -


Canon G10 No flash

WoW1 what a difference in rendition - the G10 image full-sized is pretty noisy as it is at ISO800 for a tiny sensor - K-x has no such problems - but the color rendition problems are ginormous compared to the G10, notice the over-saturation of the bass and part of the shirt to glaring white (rightmost person) this is not just overexposure - but the K-x not coping with the extreme magenta lighting so it's clipping the either the red or blue channels or both.....
Look also at the bass drum how ell the G10 image shows compared to the K-x image where the colors seem to be melting into each other.

How about mitigation using flash?

K-x slow-sync flash (-1 stop flash compensation)


Canon G10 slow-sync flash (-1 2/3 stop flash compensation)

the G10 flash shot looks worse than the G10 no flash -
the K-x seems better than its no flash - but look at the bassist.....

Does post processing improve things - of course it does (no EXIF) -

K-x No flash shot

just adjusted brightness/contrast - not that much better


selected white point on guitar's white pick guard - does make the nearer two people look better.

How about the worse looking G10 flash shot?

now this looks almost as good as the G10 no flash shot - so it was just exposure - probably the flash's reflection from the silver keyboard front had fooled the flash metering of the G10.......

06-28-2010, 12:13 PM   #68
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I experience similar problems when shooting lights. I found that the 'vibrance' slider in lightroom can correct for some of this effect.

Part of the problem is that you're shooting JPEG. It's too difficult to set the JPEG rendering in camera for each shot because the lighting is always changing. RAW will offer greater latitude.

Last edited by dragonfly; 06-28-2010 at 12:19 PM.
06-28-2010, 12:59 PM   #69
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Truth is the WB on the K7 is really spot on compared with the Kx. I almost always leave the WB on auto for the K7 whereas for Kx I have to change it in light other than daylight.
06-28-2010, 01:00 PM   #70
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QuoteOriginally posted by dragonfly Quote
I experience similar problems when shooting lights. I found that the 'vibrance' slider in lightroom can correct for some of this effect.

Part of the problem is that you're shooting JPEG. It's too difficult to set the JPEG rendering in camera for each shot because the lighting is always changing. RAW will offer greater latitude.
Thank you for your advice -

Yes... perhaps, and I am not being argumentative -

If you'd kindly look at the link I provided - in the post you just responded to -
post #341 by Canuke for an explanation where even RAW cannot render some of the colors....

Then in that long thread - Modern LED Stage Lighting & photography problems
Posts #23 and #79 - I have used RAW to try to mitigate some of the problems

You mentioned you use LightRoom which is based on ACR since it is still Adobe - please read particularly Post #23 where ACR singularly failed to render a scene captured by the K-x correctly - I had to use Pentax DCU/SilkyPix to get my final results.

So RAW is not a panacea, and cannot do everything that many seem to offer as an instant solution -
believe me I have tried, and I am not exactly that inexperience at this -
please look at the sheer number of posted photos in my sig link, and the photos posted in this very thread.

But like I said I am not being argumentative or trying to be rude -
as I hear this RAW will do it advice all the time -
and I have used RAW under these circumstances and it does sometimes do better - but not all the time -
often JPGs can and will do just as well (please see post #79 )
- it's not the dynamic range/color depth that's the problem -
but the color range/gamut captured by the RGB Bayer matrix sensor
- and RAW cannot help where it's not captured properly in the first place.

Thanks for your input,
06-28-2010, 01:09 PM   #71
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QuoteOriginally posted by kytra Quote
Truth is the WB on the K7 is really spot on compared with the Kx. I almost always leave the WB on auto for the K7 whereas for Kx I have to change it in light other than daylight.
Truth is the AWB on the K-x is very similar, if not the same as the K-7....
since the K-x inherited a lot of its features/functionalities from the K-7

and like I have clearly said right at the top of my post - the K-x AWB does miraculously well under most normal circumstances
- it's just under the more extreme lighting using almost mono-color lighting that it has difficulties - and even manual white white balance cannot help under those circumstances.

Try shooting with the K-7 under pure magenta lighting using only Red and Blue LEDs to make up that color - to see what I mean - I actually would be surprised if any Pentax dSLR can manage that well...
but I'd be more than happy to be corrected.
06-29-2010, 12:23 AM   #72
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QuoteOriginally posted by UnknownVT Quote
Try shooting with the K-7 under pure magenta lighting using only Red and Blue LEDs to make up that color - to see what I mean - I actually would be surprised if any Pentax dSLR can manage that well...
but I'd be more than happy to be corrected.
Generally you take pictures of a subject to "capture the moment". So under artificial lighting, should we try to replicate the original lighting, rather than try to show natural (under day light) skin color?
06-29-2010, 05:48 AM   #73
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QuoteOriginally posted by UnknownVT Quote
Truth is the AWB on the K-x is very similar, if not the same as the K-7....
since the K-x inherited a lot of its features/functionalities from the K-7

and like I have clearly said right at the top of my post - the K-x AWB does miraculously well under most normal circumstances
- it's just under the more extreme lighting using almost mono-color lighting that it has difficulties - and even manual white white balance cannot help under those circumstances.

Try shooting with the K-7 under pure magenta lighting using only Red and Blue LEDs to make up that color - to see what I mean - I actually would be surprised if any Pentax dSLR can manage that well...
but I'd be more than happy to be corrected.
I don't know about the K-7, but I agree that the K-x does remarkably well with its AWB, especially compared to other cameras. If you don't like where the K-x came out, a slight tweak in light temperature is a very easy pp anyway. The only time I've had the AWB fail significantly is when the scene has two very different light sources, such as an open window in a room primarily lit by tungsten lights. No camera or even automated pp can be expected to nail that.
06-29-2010, 08:55 AM   #74
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QuoteOriginally posted by Deni Quote
Generally you take pictures of a subject to "capture the moment". So under artificial lighting, should we try to replicate the original lighting, rather than try to show natural (under day light) skin color?
This is a good point -
I do normally basically try to present the scene "as I see it" - and have said so -
that's why I am mostly happy with JPG - I treat shooting JPG akin to shooting slides - except of course with digital there is the opportunity to easily tweak one's photos with PP.

However since whenever I bring up difficulties in certain colored lighting conditions - eg: mono-color or even worse magenta made up by Red and Blue LEDs only - inevitably someone will say categorically it's because I am shooting JPGs, and RAW would solve the problem.

So I took a paired RAW+JPG with strong magenta lighting (using red and blue LEDs only) to illustrate that even RAW would struggle with this.

As for white balance when there is only mono-color or magenta - even manual white balance would not be able to "get" a natural balance because the color weren't there in the first place.

Although I did have to kind of eat my own words as illustrated in Post #23 -
of the thread Modern LED Stage Lighting & photography problems -
where we discussed this issue more thoroughly than touched upon here.
But note in the post (#23) where I ate crow -
the only RAW converter that actually managed under those extreme conditions was Pentax DCU/SilkyPix 4.11 -
even ACR (Adobe Camera RAW) 5.6 (the latest version at the time that fully supported the K-x) could NOT manage anything acceptable -
since it is also Adobe - LightRoom 3 Beta could not do it either.

But this is not my normal processing objective.

However occasionally - since the stage lighting changes as one shoots - there could be a potentially good shot but the colors are just not right - so I have attempted to get a better balance PP -

I also thought RAW might give me better flexibility - and in a few cases it did -
but mostly I found as shown in Post #79 - JPGs did just as well.

Thanks for bringing out that aspect.
06-29-2010, 09:17 AM   #75
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QuoteOriginally posted by GeneV Quote
The only time I've had the AWB fail significantly is when the scene has two very different light sources, such as an open window in a room primarily lit by tungsten lights. No camera or even automated pp can be expected to nail that.
Another good point Gene -
for the difficult stage lighting - sometimes if there is strong tungsten back-lighting and I include the tungsten light source in my composition it could fool the K-x AWB to render the main subject that may be in LED lighting to be too blue - at least much bluer than I saw - but like you said probably no other camera could do it correctly anyway - and the K-x would not have been able to read my mind to "see" what I saw (although I sometimes wished it could!).

But to show how well the K-x AWB actually does -

not too challenging - but notice the blue on the edge of the partitioning wall to the left?

this may show it a bit better -

this shows that there was mixed lighting here.....
caused by -
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