September 17, 2014, 04:07:40 PM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - dafrank

Pages: [1] 2 3 ... 7
Lenses / Re: Best short telephoto?
« on: July 05, 2014, 03:58:35 PM »
To circumvent this rule, and, if a long to very long lens will help, the obvious answer is a folded path mirror lens. Here is one for Canon EOS mounts : Rokinon ED500M-EOS 500mm F6.3 Mirror Lens. You can use a search engine to find this or one of the many others available in a range of apertures and focal lengths, all under 5 inches long. Other possibilities are some of the many "shorter" non-mirror longer lenses, along with a 1.4x or 2x extender. Good luck, David


Almost forgot about Da Rulez. 

Rule 1:  I've given evidence and examples.  They're all in my 13173-and-counting posts.  This may help.

Rule 2:  This thread will undoubedly fall victim to one of the classic blunders!  The most famous of which is "never get involved in a land war in Asia," but only slightly less well-known is this: "Never quote The Princess Bride in a CR Forum thread, it's a sure way to get a thread locked."

First of all, it is inconceivable that you have posted so much, usually so well, and truly, you have a dizzying intellect, yet you have still never gone up against a Sicilian when death was on the line, to prove just that point.

My name is David Franklin, prepare to reply, if you wish.

Software & Accessories / Re: Canon Utilities and CS6 with 5Dlll
« on: May 02, 2014, 09:28:40 PM »
I use DPP, Lightroom, Photoshop and Photoshop Camera Raw, Photo Ninja, Photomatix Pro, Oloneo PhotoEngine and DXO ViewPoint at various times, under various workflow circumstances, and have extensively used - although not lately - Capture One. I shoot with 5D3's only right now. Here's what I think about DPP. The Quick check tool (see tool menu) is as good as or better than any other converter for getting a good, edit level look (at 50% OR 100%) at your shoot, as long as the list of files you select for the tool does not exceed somewhere north of a 100 or 150 files at a time. Beyond that, DPP, because it is only an 8 bit program and is not very efficient at memory use, craps out with an out-of-memory issue. This sometimes also happens when you try to use the raw file HDR tool, if the 3 selected files hold a lot of very fine grained detail - memory error again. Other  than the above problems, if you don't need an archiving image data base, DPP is still a valuable tool for easily getting better than Jpeg conversions, but with less refinement and not as fine-grained control as are available in other applications. My advice is, unless you have a tiny hard drive (no offence meant here) without much extra capacity, install and keep most of your Canon software disk contents. Good luck.


EOS Bodies / Re: New Sensor Technology Coming From Canon? [CR1]
« on: April 29, 2014, 01:30:21 PM »

The clipped corners aren't a problem because of the way light travels when leaving the lens - think of it as an expanding cone, so the image circle is physically smaller at the lens mount than when it hits the sensor.  Just look at the back of the EF 40mm f/2.8, the rear element is significantly smaller than a FF sensor:

OTOH, there may be issues with some lenses with a large aperture and an exit pupil close to the image plane (similar to the 'clipped' bokeh of the 85L wide open with close subjects).

Even simpler to explain how full frame could work, with unclipped corners, using the M mount: the imaging light is projected from the lens to the sensor from the last element at the back of the lens, which is, I think, always situated slightly behind the plane of the lens mount, not at or in front of the plane of the lens mount. Simple. All other explanations are surely true, but none, other than the above, is necessary.


Lenses / Some answers
« on: April 21, 2014, 03:43:25 PM »
Perhaps, I can be of some assistance in understanding a couple of questions or assertions that have been made in this thread.

First of all, Canon does offer both swing or tilt of the lens (front focus plane) on all their TS-E lenses. An analog of view camera tilt is available, defined by the lens plane moving through a defined vertically oriented arc that travels around the horizontal axis traveling through - and in front of and behind - the central, near nodal point of the lens. After rotating the mount 90 degrees, the TS-E lenses can use the exact same controls as were used for the tilt movement to swing the lens plane through a defined horizontally oriented arc that travels from left to right, around the vertical axis going through - and in front of and behind - the central, near nodal point of the lens. And if you choose to rotate the lens mount less than 90 degrees off either the vertical or horizontal axes, you will be able to combine the effects, somewhat, of both a swing and a tilt of the lens plane, the effects depending on the position of the mount.

As to the person who speculated that perhaps Canon was going to make the lens able to swing, as well as tilt, well, the above paragraph explains that that is already possible. However, if the poster is referring to the true capability of a monorail (non-monorails can also do this, but usually only tilt from the bottom, rather than the center) view camera, then, no, no current TS-E lens can achieve that. This is because, besides being able to swing/tilt the lens plane only, as TS-E lenses do, a monorail view camera can also swing/tilt the image plane (for view camera, it's the film/digital back; for a DSLR it would be the entire camera with sensor, but not lens), independently of whatever one chooses to do with the lens plane. Therefore, the view camera can swing or tilt either the front or back, in whatever direction one chooses, or swing or tilt them both at the same time. The uses of this are quite important. Tilting or swinging the back not only helps to indirectly manipulate the front focus plane much like the camera front does, but it can do something else quite important; it can effect the apparent distortion of the subject, from rectilinear-looking to comical levels of "distortion," stretching or compressing the subject to either "correct" its look or purposefully make it look less realistic. Then, oftentimes, the front is counter-moved to reset the focus plane to make up for the change of the image plane, so that the so-called Scheimpflug effect can still bring about relatively sharp focus.

Given the above, Canon could actually make a lens with two tilt/shift mechanisms, one in the "normal" position to allow front lens plane manipulation and one at the base of the lens to simulate rear standard image plane manipulation. The lens would be horribly complicated to make, and the glass itself would have to deliver a truly massively larger image circle than normal "full-frame" lenses, or even existing TS-E lenses, to compensate for the possible off-angle light projection of the two different standards. But, this could be done, especially so with a lens longer than 90 mm. I doubt if Canon, or any other lens maker will ever actually do such a thing, but it would be possible.

And as to whether having a super-telephoto-like lens mount adapter on a TS-E lens would make multiple exposure panorama-making easier, by not affecting the perspective of the multiple shifted exposures, the answer is: I think so. One TS-E's shifted lens view's perspective will not exactly match the perspective of a view from an image shifted along the same axis by the same lens, unless an appropriate image plane shift could mitigate it. To do this properly, it would work best if only the camera-sensor back itself were shifted through the image plane, and, when the lens itself is immobile on a tripod, the lens movements themselves actually serve to move only the camera body through the immobile image plane. If this does not seem practical for the owners of existing TS-E lenses to achieve, it is good to know that it is not always necessary, given the "fudge factors" available in post-processing, and that it is still possible to achieve with some extra effort and cost, via various adapters and rails.

I hope this helps.


Lenses / Re: DXOMark: Samyang 24mm f/1.4 for Canon
« on: March 13, 2014, 12:35:10 PM »
Actually, the DXO review for the Samyang, if anything, pretty much convinced me to consider buying the 24mm f/2.8 Canon IS prime. IS - good for 3 or 4 extra stops with static subjects and video, plus very good sharpness wide open, good construction, guaranteed camera compatibility, small size, light weight, exif communications and a price just above the Samyang and less than half of the faster Canon, makes the lens the rational choice for those that don't absolutely have to have the extra 1.5 (likely "real" T-stop difference) stops faster aperture or the tilt/shift ability of the 24mm TS-E. Of course, YMMV, but I can't see how this isn't rational and true, and I know that, even with very fast (f/1.2 to f/1.4) lenses, I rarely actually shoot at maximum aperture, because I usually want that slight extra sharp focusing margin that a slightly smaller aperture affords.


Photography Technique / Re: Product photography with shiny objects
« on: February 13, 2014, 11:35:15 AM »
Best solution is to first is to set up the shot exactly how you want to show the product, then note the field around the subject and literally mark off the exact space being reflected in the product. What you should be trying to achieve is to add highlights to define shape and texture and solid blacks or gray gradients where defining highlights aren't necessary. Hang black and/or gray cloth in the reflected field and add large soft and diffused highlights with lightbanks, diffuser shoot-throughs or lit foamcores as needed. Or just hire a competent professional. Good luck.
Regards, David

These look familiar; I've long known about such things from reading newspapers and magazines, rare bouts of watching TV news and occasionally being "hypnotized" by the always lurid prison porn that is shown, usually late at night, on MSNBC, usually the most interesting thing that that cable channel runs on air.

A couple of the shivs look like they might be constructed of "starched" cardboard. Is that correct? If only those benighted sociopaths would apply just some of their energy and resourcefulness to honest work, we'd have a very little better economy, and they'd be a lot happier themselves. Too bad.

Many years ago, I covered a prison riot for Time magazine at Jackson Prison in Michigan. Scary places, those maximum security lock-ups. I hope you don't have to be too involved with the population in your work. It will be a lot better for your mental health if this was the last time you had to go inside the walls.

As far as photography and Canon goes, well, I'm kind of glad I didn't get the point. ;)


EOS Bodies / Re: Canon Teaser
« on: November 08, 2013, 02:02:29 PM »
"... Canon will start from the white world ..."
So rife with politically incorrect double entendre it almost seems like an Onion headline.

That sounds like a very literal translation. I wonder if it means something like "Canon starts from a blank slate".

I'll ask my Korean colleague when he comes back from lunch.

Yes, that's exactly what I thought when I read the machine-translated post - that what they probably mean is that Canon has created a new camera from a "clean sheet" of white paper, as the expression goes in the U.S., as it probably also does in other English-speaking nations. This would be a very nice surprise, if true. If not, it may also mean that (ugh!) Canon has fallen back on that desperate standby - kitchy styling - to bolster their sales and has created a literally all white painted version of the SL1 to sell to young Asian women to go with their Hello Kitty accessories. I guess we'll all know pretty soon, but I don't expect any real breakthroughs here. Just saying.

Regards, David

Third Party Manufacturers / Re: Sigma 24-105 f/4 DG OS Sample Images
« on: October 31, 2013, 09:05:35 PM »
The cyan-red lateral chromatic aberration is very obvious in all of the 5 or 6 shots I looked at full-size. It does not look up to the recent standards established by the faster Sigma "art' lenses in general with the LCA and soft corners at wider angles, etc. I would definitely pass unless the lens sold for under $500.00, and was used as a fun walk -around only. Not up to professional standards, especially for an f/4.0 lens. Canon's 24-70 f/4.0 is also flawed, but I think that, if memory serves me, the Canon 24-105 is better than this. This figures, as Canon appears ready to soon replace their 24-105, as a kit lens, with the substandard 24-70 f/4.0. Perfect. ::)


All the previous posts do well to specifically answer your question as to the dual pixel advantages in focusing. However, there are some possibilities that may or may not actually ever be incorporated into later designs, using dual pixels, which could open up a number of options not now available. Somewhat like Fuji in some of their recent sensor designs, Canon could actually use one pixel in each pair for reading highlights and the other for reading shadows, thereby creating a sort of instant HDR exposure, increasing DR by quite a lot. Other arrangements could also be made to use one of each pair to read color information separately and differently from its mate in the same pair, thereby increasing color depth and accuracy. I'm sure that many things that others could think of, would also be possible , but these are some that sound interesting to me. Whether any of this could or will actually happen is another thing entirely. Maybe Canon already has this in mind, maybe not.


Lenses / Re: New Tilt-Shifts in 2014, Other EF Lenses in 2013 [CR2]
« on: July 13, 2013, 12:19:57 PM »
As a longtime tilt-shift and studio monorail view camera user, I love my current 90mm TS-E, which is nearly flawless optically "as is." About the only things that could significantly improve it would be better anti-reflection coatings, independent rotation of tilt and shift functions - as in the current 17mm and 24mm versions, and bigger beefier control and locking knobs. That said, I probably won't rush to replace my current 90mm lens. My old 24mm TS-E is another matter.

There are two TS-E lenses I really want/need for my type of work, at least one of which I will purchase this year: 1) the 17mm f/4.0 and 2) the 24mm f/3.5 version II. Aside from these two, I would love to have a 135mm f/4.0 TS-E for product work, with near macro capabilities. This longer focal length would go a long way to cement the market for Canon among studio shooters who formerly migrated from large format film to medium format digital backs on view and technical cameras because of the availability of larger image circle type view-camera-like "digital" lenses from Schneider and Rodenstock. With the now supposedly soon-to-come very large megapixel full-frame camera arriving this year or next, Canon would have a shot of eating into that professional market with just another very high quality TS-E lens or two. A TS-E lens longer than 90mm would give these shooters a way to reduce perspective distortion in many product images, such as in automotive and other larger object photography, as well as in ordinary table-top set-ups. Anything from 120mm to about 180mm would be great; I just picked 135mm as a practical and well-worn focal length. In fact, a 120 to 180 f/4.0 - or even a variable aperture f/4.0-f/5.6 - TS-E zoom would be amazing. All this aside, I imagine Canon will most likely just produce the more pedestrian choice - 35mm f/2.8 TS-E. Well, there's always hope, isn't there?

Lighting / Re: Softbox Size question
« on: July 07, 2013, 02:18:31 PM »
Of course, this is one of those questions that are insoluble to those who are not actually living your own life. But, there are some rules of thumb to go by that might help you to understand diffuser (softbox light is diffused light) light sources.

Most people, even some photographers, mistakenly think that the softness (lower overall contrast, with lighter shadow values compared to harder lighting having comparable highlight values) comes from the evenness of the light source, such as light that is bounced off a large reflecting board or diffused through a medium such as translucent cloth, vellum or plastic. This is only about 1/4 right. The "softness" from these light sources is actually solely due to the overall size of the light emitting surface in relation to its distance from the subject. If a source is very uneven, with much brighter areas surrounded by those less illuminated, then the size of the source can mainly be measured by the part of the source which is most bright, like the light coming from an old fashioned photo flood fixture, and would actually measure as smaller overall than the size of the reflector. This is why the most efficient way of delivering soft lighting from a source of a certain measured area will usually be from an evenly illuminating source such as a softbox, light reflecting off a board or wall, or even a well made umbrella. But, the real data that counts is still how big the illuminating source is compared with the distance to the subject.

Understanding this should give you an idea how to calculate how big your softboxes should be to work for your subjects and your preconception of the quality of the light. If you cannot vary the distance from multiple illuminating sources to your subject by very much, then, in order to change the soft-hard quotient of the lighting from more than one softbox source, one would require different sized softboxes to accomplish the desired effect. Also, things such as overall space requirements, weight on - and position of - the lighthead (torque strain), portability, cost and many other factors might lead you to choose boxes of different sizes.

Think about what you may have to shoot and figure it out for yourself.

Regards, David

The Japanese Yen has fallen considerably in value in recent months. Japanese exports should therefore be much cheaper now for buyers, so why are Canon prices remaining so high? I'd love a new Canon 5D mk III but current MAP limitations are keeping prices high and stopping me from buying.

I have read many, but not all of the replies, so please forgive me if I repeat something someone else has already stated.

Unfortunately, you are thinking in ways that don't correspond to how businesses actually work. It is easy to do this because many of us tend to think of how we would behave - if we were perfectly selfless individuals acting on a one-to-one basis with a friend or relative - in setting prices on something or other ourselves. In this regard, corpporations, as well as individuals in business, who make and/or sell goods or services in the universal market environment in which we all conduct our financial transactions behave, at the most basic level, according to two principals: 1) they set their prices to maximize their income and profit, while always being careful not to set prices higher than would be the level to suppress demand, and 2) try not to churn the market by changing their prices too often or too rapidly, in order not to create ill will or confusion among their customer base and avoid pricing mistakes by basing their profit assumptions on too short a data sample.

Under the above realities, Canon has done two things: 1) when the value of the yen rose, it did not raise U.S. product prices as high or fast as the monetary valuations would suggest, and 2) when the value of the yen fell, it did not lower U.S. product prices as low or fast as the monetary valuations would suggest. And, if after testing the market for a period of time during which its competitors do not lower their prices and/or Canon's sales do not diminish or sales growth slow, they will probably take advantage of the period of lower yen evaluations to raise income and profit.

In short - no surprise here - the business world continues to operate under well known principles of supply and demand. "Fairness" in pricing is a principle that only exists in the minds of the naïve or schemes of various collectivist-minded "planners." The reality is that Canon will set its prices to maximize its income and profits, and only if the price levels they set punish them by reducing those two metrics, will they reduce their prices at all.


Lenses / My wanted list -probably a little different
« on: May 14, 2013, 06:02:00 PM »
Since I shoot some different things than most, I'd like to have a few different lenses which not be found on most other peoples' radar:

135mm - 180mm TS-E f/4.0 with both great far field and very good close-up capabilities, plus 3 axis IS (dream on) for a long-ish product lens with nearly zero per cent color aberrations and killer sharpness out to the edge of the image circle. The 90mm doesn't cut it for very large objects (cars, cars, cars) at extreme oblique angles when trying to maintain a relatively "normal" size perspective between the near and far portions of the subject matter.

Super high resolving, super high contrast 50mm f2.0 L with IS.

Super high resolving, super high contrast 16-24mm f/2.8 L with IS.

Super high resolving, super high contrast 24-50mm f/2.8 L with IS.

Super high resolving, super high contrast 50-105mm f/2.8 L with IS.

Modestly priced 400mm f/4.5 L IS

In all of the above lenses, except the TS-E, my purpose for specifying them as I did, is to trade aperture or zoom ratio for better image quality, something I would prefer to have, especially in light of the (hopefully) very high resolution per image area sensor cameras coming pretty soon. Whether these cams use smaller pixels, true color pixels, pixel-shifting multiple exposure techniques or some other method to yield their higher image resolution, better lenses will make them all the more useful.

Just my thoughts.


Pages: [1] 2 3 ... 7