parkmcgraw

parkmcgraw

Joined on Apr 15, 2011

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Total: 57, showing: 1 – 20
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On Hands on with the Pentax 645Z article (654 comments in total)

Being that I frequently reap the many benefits associated with have a reflex mirror and interchangeable screen am very happy that the viewfinder on this camera is not a "third order" at best, electronic display with vastly reduced inherent display reproduction resolution.

An eyepiece magnifier on an electronic EO display being of little help, incapable of utilizing the inherent available resolution in the viewfinder optical path.

On dark site locations, the false illuminance produced from the display itself interfering with a person's dark adapted vision, not the least the added current load on the battery pack to process and generate the display.

On many situations, preferring the viewfinder image to be available at all times for many continuous hours in the field during all lighting conditions, used for many hours each day, repeated for days at a time, intermittently activating a camera's electronic metering, control systems and electronic display only when needed.

Park McGraw

Direct link | Posted on Apr 16, 2014 at 08:49 UTC as 99th comment
In reply to:

Mario G: In #5 I was surprised that the moon was not in focus when the far distance to the people should have made it focusing infinity. But then I read an article saying that it was actually focusing infinity, and the moon was blurry due to atmospheric refraction... quite an interesting way to get some extra bokeh in your shots, assuming that you can put your background in orbit.

Hello Mario G

If there was that much atmospheric turbulence as a result of thermals, such that the moon would be so grossly out of focus, would also imply that the images of the individuals, and about 3' arcmins in height, the moon being about 30' arcmins in diameter, would also be somewhat effected, but they are not.

The moon presenting every little distortion in addition to uniform blur about the circumference, though spanning multiple atmospheric cells, suggesting to me that the moon is simply out of focus in the far field.

I have about 25 years experience with adaptive optics (AO), originally called (CIS) compensating imaging system by ITEK for the KH program, myself having worked on a ground based KH11.

Park McGraw

Direct link | Posted on Feb 24, 2014 at 10:15 UTC

Astrophoto #1, a pretty when left at reduced scale.

At unity, should this image be natural and not a stitched collection or series of overlaid frames, revealing that the lens has some VERY bad zonal problems relative to distortion and aberrations, if not some of the worst I have ever seen outside of toy optics, for example the star field between the Magellanic Clouds.

Hence, would like to know how the image was collected, with what optics and post processing if any being that the star fields for many regions of the frame DO NOT LOOK NATURAL, the tracking errors being non uniform.

For a point of reference, I have been taking day and night astrophotos with standard 35mm type cameras and lens, medium format, to custom made optics since the 1970's, recording on 103F, Tri-X to Ektachrome, nitrogen baked hyposensitized film and cold cameras, to large format CCDs and APO optics, working at such places as Keck, Lick, AMOS MOTIF, images published in Astronomy Mag and elsewhere.

Park McGraw

Direct link | Posted on Feb 24, 2014 at 10:04 UTC as 5th comment

1 of 3

This new camera from Canon, much like similar offerings from other manufactures, regardless of body style, if properly conceived of as a fieldable "35 mm" non laboratory environment like camera will be SUBJECT MATTER COMPOSABLE WITHOUT THE NEED OF TURNING ON ELECTRICAL POWER, or require one to look upon an illuminated screen displaying 3rd order at best image quality with false field illuminance.

On the whole, nearly every camera body being produced and designed today appearing to be fashioned for mentally lazy individuals not wishing to be technically proficient, less relegated to a preconceived of 2 dimensional range, void of much subject matter depth and discipline (a.k.a. subject matter fakes) unlike any time before in the history of photography.

What is being offered today little more than GARBAGE with near unethical planned obsolescence for the sole purpose of increasing short term corporate profit margins, and not long-term product usage.

Direct link | Posted on Feb 13, 2014 at 07:41 UTC as 17th comment

2 of 3

Little sold today of heirloom design or quality. The trend in the past two decades being to continually lower the bar on the full performance and tool range of the hardware offerings.

The supervising managers that have decided to remove optical viewfinders in place of EO only viewfinders, more than likely removing the simple yet highly functional, low maintenance, low component count transparent windshield from a car or motorcycle helmet.

Choosing in favor of a less visually true, less fault tolerate cranky solution that is difficult to physically service, composed of chemically less stable internal components prone to accelerated decomposition (highly dependent on homogeneity), critically dependent on consumable items (batteries) that functions via an (default condition) opaque screen, that in operation results in reduced visual fidelity, most likely laden with marginally valued added distracting functions.

Direct link | Posted on Feb 13, 2014 at 07:41 UTC as 18th comment

3 of 3

The camera body offerings today, somewhat analogous to how a fledgling and or pretentious cook, as appose to a skilful chef, creates a "what is that" sort of desert, not being knowable or skillful enough in the arts to produce a basic though very high quality cake or seasoned pie with ice cream.

In closing, please STOP removing basic system hardware functions and or options without first insuring that what is being selected to be the replacement item is superior on most all respects to the predecessor.

Do a job, big or small, do it right or not at all.

Park McGraw

Direct link | Posted on Feb 13, 2014 at 07:41 UTC as 19th comment | 2 replies

1 of 3

This new camera from Sony, much like similar offerings from other manufactures, regardless of body style, if properly conceived of as a fieldable "35 mm" non laboratory environment like camera will be SUBJECT MATTER COMPOSABLE WITHOUT THE NEED OF TURNING ON ELECTRICAL POWER, or require one to look upon an illuminated screen displaying 3rd order at best image quality with false field illuminance.

On the whole, nearly every camera body being produced and designed today appearing to be fashioned for mentally lazy individuals not wishing to be technically proficient, less relegated to a preconceived of 2 dimensional range, void of much subject matter depth and discipline (a.k.a. subject matter fakes) unlike any time before in the history of photography.

What is being offered today little more than GARBAGE with near unethical planned obsolescence for the sole purpose of increasing short term corporate profit margins, and not long-term product usage.

Direct link | Posted on Feb 13, 2014 at 07:36 UTC as 4th comment | 1 reply

2 of 3

Little sold today of heirloom design or quality. The trend in the past two decades being to continually lower the bar on the full performance and tool range of the hardware.

The supervising managers that have decided to remove optical viewfinders in place of EO only viewfinders, more than likely removing the simple yet highly functional, low maintenance, low component count transparent windshield from a car or motorcycle helmet.

Choosing in favor of a less visually true, less fault tolerate cranky solution that is difficult to physically service, composed of chemically less stable internal components prone to accelerated decomposition (highly dependent on homogeneity), critically dependent on consumable items (batteries) that functions via an (default condition) opaque screen, that in operation results in reduced visual fidelity, most likely laden with marginally valued added distracting functions.

Direct link | Posted on Feb 13, 2014 at 07:34 UTC as 5th comment

3 of 3

The camera body offerings today, somewhat analogous to how a fledgling and or pretentious cook, as appose to a skilful chef, creates a "what is that" sort of desert, not being knowable or skillful enough in the arts to produce a basic though very high quality cake or seasoned pie with ice cream.

In closing, please STOP removing basic system hardware functions and or options without first insuring that what is being selected to be the replacement item is superior on most all respects to the predecessor.

Do a job, big or small, do it right or not at all.

Park McGraw

Direct link | Posted on Feb 13, 2014 at 07:33 UTC as 6th comment | 4 replies
In reply to:

Chanthis: $1600 for a m4/rds lens? LOL, there's one born every minute.

Hello razorfish

Your chain of self gratuitous and generally disrespecting comments relative to the subject matter and posters, are non value added retorts wielded by an individual whose writings appear at best, to be emanating from a source not ever formally educated or trained in optics, in effect wearing your lower sphincter like some sort of chic turtle neck sweater.

Park McGraw

Direct link | Posted on Jan 8, 2014 at 13:14 UTC
In reply to:

parkmcgraw: 2 of 4

2] "... uniformed descriptiveness from center to edges ... beautiful soft focus ..."

This claim is a contradiction. The process of soft focus, less an area specific aperture mask, affecting the entire field of view of the imager, including the principle axis. Hence, no lens that has a soft central field can also claim to have "uniformed descriptiveness" more professionally and less pretentiously addressed as "uniform image quality" for the entire "field of view" (FOV), or focal plane.

3] "... shallow depth of field ... unique to the large aperture lens ..."

Is not a correct statement as "shallow depth of field" is a product of "lens or optical speed" (f ratio, i.e. solid angle), apparent or real and not just the diameter of the aperture. The optical speed, thus depth of field of a system being a ratio of "lens aperture diameter" and "lens focal length", e.g. Large Aperture, short focal length, shallow depth of field; Large Aperture, long focal length, deep depth of field.

Hello joejack951

Your reply to my posting is an indication that you do not understand or comprehend the full nature and differences between "bokeh" and "soft focus".

Bokeh (out of image plane) and Soft Focus (in plane) being two completely different optical factors.

For your benefit, "soft focus" deals only with the formed spot diameter properties of "in focus" images at the image (focal) plane.

Bokeh deals with the bisymmetry of focused spot diameter properties "in front of" and "behind" the image plane, hence the "out of focus images" formed.

In short, a soft lens is soft for the entire field of view, including the on axis image, and point that escaped you having given little contemplation to the posting I shared.

In addition, your are arrogant to understand that it is your place to tell anyone "get over it". Rest assured, you'll not be performing optical duties in any of the labs I supervise.

In closing, no name, no creditability.

Park McGraw
www.phisicalpsience.com/about

Direct link | Posted on Jan 8, 2014 at 12:46 UTC
In reply to:

parkmcgraw: 3 of 4

4] " ... slight handshake ... images ... out-of-focus ... POWER O.I.S. (Optical Image Stabilizer) ... effectively compensates ... easy to capture ... low-lit situations"

Rubbish, focus (minus atmospheric turbulence and high approach rates) is typically a longitudinal function between the subject and focal plane. The emphasis of O.l.S. is for compensating orthogonal motion of the focal plane, and not longitudinal motion.

Changes in longitudinal distance to the subject, due to orthogonal translations being a very small cosine theta value on the order of mm or less, minus imaging in the extreme near field (e.g. macro).

Shake induced errors, or blurring of the image, regardless of lens design and speed, being controlled by exposure time relative to the velocity (motion) of the image across the focal plane, and not the trivial mm scale longitudinal translations induced from orthogonal (linear or circular) motion about the optical axis separating the camera from the subject.

Hello joejack951

You ask if I have experience with fast systems.

As an Astro photographer with 35 years experience and former freelance for weddings to Budweiser speed boat racing, YES.

Spanning from "noct" lens, Global Hawk EO (optical integration and characterization optical facility Engineering Design Lead - Hughes/Raytheon), 10m Keck Telescope, to coupling the worlds brightest weapons grade laser (Northrop Grumman).

What is your experience set or are you just a loose pen?

Direct link | Posted on Jan 8, 2014 at 12:00 UTC
In reply to:

parkmcgraw: 4 of 4

5] "... superior inner focus system, ... excellent resolution and contrast from close-up to infinity. "

The correct terminology, as appose to "inner focus" is "near field", the inverse term being "far field". The verbiage "inner focus" already assigned to describing the optical region just forward of the image plane, and does not refer to the object distance, near or far field.

In the future, the process for selecting optical (lens or imaging) reviewers and or responsible editors at dpReview, doing well to question the potential candidate if they have actually made a lens, camera body or worked in a professional optical facility for two decades or more.

Until then, I kindly suggest that the individual(s) leading dpReview acquire competent subject matter experts/mentors for the dpReview writing staff, sending the "undisciplined, make stuff up on the fly" chalk board or consumer only candidates down the road.

Park McGraw

Hello Joejack951

The IF by Nikon stands for internal focus, not inner focus.

Pretentious people such as yourself, confusing non education and experience for competence being much of the problem with such technical subjects.

Do you always make erroneous excuses for bad behavior.

Most of the people that I know which speak Japanese, including my mother and girlfriend, and to some degree myself, with ESL skills not making such translation mistakes.

Direct link | Posted on Jan 8, 2014 at 11:52 UTC

1 of 4

Are the lens reviews published by dpReview purposefully attempting to dumb down the readers, habitually 60% correct, or are the writers at dpReview simply and habitually working beyond their subject matter comfort zone and or technical level of proficiency?

This article being another disappointing report and or supplied text that arbitrarily disrespects industry established verbiage, thus convoluting the subject matter of optics and photography, apparently encouraged and or escaping past a management accustom to low performance standards (a.k.a. more apt at providing excuses for mediocrity and ultimately bad behavior).

1] "... portraits with rich stereoscopic effect ..."

No monocular system, forming a singular imaging upon a single focal plane, such that any given point on the focal plane sees an identical image (aperture), does not produce "stereoscopic effect" but rather the "perception of depth".

Direct link | Posted on Jan 7, 2014 at 01:09 UTC as 36th comment | 4 replies

2 of 4

2] "... uniformed descriptiveness from center to edges ... beautiful soft focus ..."

This claim is a contradiction. The process of soft focus, less an area specific aperture mask, affecting the entire field of view of the imager, including the principle axis. Hence, no lens that has a soft central field can also claim to have "uniformed descriptiveness" more professionally and less pretentiously addressed as "uniform image quality" for the entire "field of view" (FOV), or focal plane.

3] "... shallow depth of field ... unique to the large aperture lens ..."

Is not a correct statement as "shallow depth of field" is a product of "lens or optical speed" (f ratio, i.e. solid angle), apparent or real and not just the diameter of the aperture. The optical speed, thus depth of field of a system being a ratio of "lens aperture diameter" and "lens focal length", e.g. Large Aperture, short focal length, shallow depth of field; Large Aperture, long focal length, deep depth of field.

Direct link | Posted on Jan 7, 2014 at 01:09 UTC as 37th comment | 3 replies

3 of 4

4] " ... slight handshake ... images ... out-of-focus ... POWER O.I.S. (Optical Image Stabilizer) ... effectively compensates ... easy to capture ... low-lit situations"

Rubbish, focus (minus atmospheric turbulence and high approach rates) is typically a longitudinal function between the subject and focal plane. The emphasis of O.l.S. is for compensating orthogonal motion of the focal plane, and not longitudinal motion.

Changes in longitudinal distance to the subject, due to orthogonal translations being a very small cosine theta value on the order of mm or less, minus imaging in the extreme near field (e.g. macro).

Shake induced errors, or blurring of the image, regardless of lens design and speed, being controlled by exposure time relative to the velocity (motion) of the image across the focal plane, and not the trivial mm scale longitudinal translations induced from orthogonal (linear or circular) motion about the optical axis separating the camera from the subject.

Direct link | Posted on Jan 7, 2014 at 01:07 UTC as 38th comment | 5 replies

4 of 4

5] "... superior inner focus system, ... excellent resolution and contrast from close-up to infinity. "

The correct terminology, as appose to "inner focus" is "near field", the inverse term being "far field". The verbiage "inner focus" already assigned to describing the optical region just forward of the image plane, and does not refer to the object distance, near or far field.

In the future, the process for selecting optical (lens or imaging) reviewers and or responsible editors at dpReview, doing well to question the potential candidate if they have actually made a lens, camera body or worked in a professional optical facility for two decades or more.

Until then, I kindly suggest that the individual(s) leading dpReview acquire competent subject matter experts/mentors for the dpReview writing staff, sending the "undisciplined, make stuff up on the fly" chalk board or consumer only candidates down the road.

Park McGraw

Direct link | Posted on Jan 7, 2014 at 01:07 UTC as 39th comment | 3 replies
On Nikon Df preview (2817 comments in total)
In reply to:

cruz031: The lens is not retro enough. At this price, they should bundle it with 50/1.2 at least :) And if Nikon really wanted to bring 'pure photography' back to it's users, they would tweak the sensor to have base iso sensitivity of 25, user removable color-array filter so one could enjoy black&white photography in it's purest form. Even if i personaly don't have anything against use of d600 'oil spitting' shitter, it would be better (more retro) if they opted for FM2's fully mechanical shutter ;)

Hello cruz031

The modern CCD and CMOS camera's typically do not accommodate the f1.2 - f16 Noc lens because the typical electronic sensor lacks the necessary S/N dynamic range to accommodate the lens. Film having much greater dynamic range thus fully capable of making use of such powerful optics. Adjusting the ISO range on the camera does not sufficiently compensate for the sensors 10E6 S/N limitation.

In short, you condescendingly mock optical superiority for you lack the hardware ability to competently utilize such devices.

Direct link | Posted on Nov 6, 2013 at 01:51 UTC
On Nikon Df preview (2817 comments in total)
In reply to:

jadot: Don't like this camera? Don't buy it.
Don't think the price is where it should be? Wait 6 months.
Don't think the tech/ergonomics is 'Modern' enough? Buy a D800 or canon equivalent.
Like retro, but your mom won't let you spend your pocket money on this? Buy a mirrorless/compact.

Seriously.

Hello jadot

Your suggestion to buy a “standard” direct imaging (colloquially known as mirrorless) non reflex or non pellicle (beamsplitter) camera body, today many of these camera's dependent on a second order at best regenerated electronic image with their numerous limitations, speaks volumes about the type of photography that you do, and perhaps not one well suited or seasoned enough to be giving the evolved photographer value added advice.

Direct link | Posted on Nov 6, 2013 at 01:36 UTC
On Nikon Df preview (2817 comments in total)

Hello Nikon

Sweet looking body. It reminds me of a cross between my old F-2 body morphed with a FM-2 prism and F-3 grip and shutter release.

Very disappointing that the viewfinder magnification is only 0.7x rather than >0.95x. With 0.7x making spot on manual focusing in low lighting conditions with a fast lens, that or coupled to a microscope or telescope very difficult, leading to a missed opportunity or less than idea results.

Overall, the body is a miss, having a low pixel count, not being able to record video HD at 60i or greater, no interchangeable focusing screens such as a "C" screen not the least prism, no shutter priority with AI lens, no integrated intervalometer, no dual SD slots, no USB 3.0.

I'll wait for the DF-2 should one ever be produced for like the F, it was better to have waited for the F2 adding later the DP-11 or DP-12 prism, thus upgrading the body (tool) into a F2A or F2AS. The DW-2, 6x magnifier with C screen extending the power of the camera body immensely.

Direct link | Posted on Nov 5, 2013 at 13:35 UTC as 701st comment
Total: 57, showing: 1 – 20
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