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Forum: General Photography 11-12-2017, 06:53 AM  
Anyone else finding this dull weather interfering with their photgraphy?
Posted By BrianR
Replies: 53
Views: 1,306
Same for where I am in Ontario, this puts a bigger damper on my outdoor activities than the weather. We could use a set of blaze orange cameras and lenses:D.


In any case, depressing weather or stray bullets, I've enough things indoors to photograph or work on that I'm never bored:).
Forum: Post Your Photos! 11-11-2017, 07:29 PM  
Food Hot Pepper
Posted By BrianR
Replies: 3
Views: 168
Kinds words, thanks you both!:)
Forum: General Talk 11-11-2017, 01:39 PM  
Question for native english speaker
Posted By BrianR
Replies: 13
Views: 401
I've heard "Secret Santa" used from Ontario out to BC. These involved knowing who the recipient was in advance of buying the gift.



I've been to one of these, but not by that name (I like it!). Everyone brought an item they didn't want, something new though. "Re-gifting" something you yourself had been given in the past was encouraged. Anyone stuck on what to bring could buy a gift under $10 or so, usually chocolate turned up. People took turns going up and selecting one of the wrapped items. It was a long standing party at this place, and a few of the items had made appearances for several years running.
Forum: Photo Critique 11-10-2017, 07:47 AM  
Nature A real challenge for decent composition.
Posted By BrianR
Replies: 6
Views: 264
It's a beauty Tony. The front out of focus leaf is the only one I find distracting. The flowers themselves have some damage on them, but it goes well with the colour palette. The background is bright and dark in all the right areas to emphasize your subject. Nice work.
Forum: Post Your Photos! 11-10-2017, 07:12 AM  
Food Hot Pepper
Posted By BrianR
Replies: 3
Views: 168
One of the hot peppers we grew this year, a Trinidad moruga scorpion. I've already dried nearly a kilogram's worth, yielding just over a 100 g of dried powder, so I have enough to incapacitate myself several thousand times over and I could spare a few to some fire experiments.

This is a blend of 2 exposures, one for the fire and one for the flashes to light the pepper and background. It was just easier that way, increasing the exposure time started to make the flames too much of a blob and the flashes didn't go down low enough to work with the ambient (I didn't have enough ND filters on hand to help them along). A wire support holding the pepper from below was also cloned out.



Hot Pepper by Brian Robin, on Flickr
Forum: Post Your Photos! 11-10-2017, 07:01 AM  
People Megan
Posted By BrianR
Replies: 16
Views: 551
Hard light, shmard light, you can obviously work with it. Very nicely done:)
Forum: Post Your Photos! 11-10-2017, 06:54 AM  
Macro A few macro shots
Posted By BrianR
Replies: 12
Views: 276
The earwigs are especially excellent, great work:)
Forum: Pentax News and Rumors 11-05-2017, 11:21 AM  
Latest Pentax patent for a "Tilting Sensor"
Posted By BrianR
Replies: 51
Views: 4,962
Different 'tilt'. As I understand it, all the current movements of of SR keep the sensor in the same plane, up/down, left/right, and 'tilt' aka rotate around the lens axis (edit- I think they refer to this movement as 'Roll"). This is a new 'tilt' that makes the sensor leave its usual focal plane. See Using Tilt-Shift Lenses to Control Depth of Field and the bit about "SCHEIMPFLUG PRINCIPLE & HINGE RULE", though it's a bit different since the sensor and not the lens is doing the tilting.
Forum: Digital Processing, Software, and Printing 11-05-2017, 11:09 AM  
PDCU 5 algorithms for enlargement?
Posted By BrianR
Replies: 12
Views: 390
Nope, see:

Bilinear interpolation - Wikipedia

and

Bicubic interpolation - Wikipedia

The short version - "linear" looks at two neighbouring pixels and estimates one to go in-between using a straight line (aka a linear polynomial). "cubic" looks at 4 pixels (in a row) and estimates one to go in between using slightly fancier math (a cubic polynomial). The "bi" prefix relates to interpolating a 2-d grid (like a digital photo), you interpolate in one direction (eg. to make the photo wider) and then the other direction (e.g to make the photo taller and restore proportions). It's not really done in two steps, but you can think of it that way (note the order you do the steps is irrelevant). They call it "Bilinear- (4 pixels)" as each interpolated pixel in the upsized image will depend on 4 pixels from the source image, in bicubic they depend on 16.



According to "some guy":D here https://www.pentaxuser.com/forum/topic/a-mini-guide-to-pentax-digital-camera-utility-38330

"One setting which may have general significance is on the ‘Image Display’ tab – Pixel Interpolation, with three options; Nearest Neighbor, Bilinear & Real Zoom. I wasn’t sure really myself on how these would affect the preview image, so I queried it on the forum, and Team Member John Riley kindly suggested that Real Zoom might equate to ‘Bicubic’,"

This was PDCU-4, but I'd expect the naming convention to be the same. I don't know who John Riley is or if we can consider this to be authoritative. If you're really concerned about the algorithm used, you could probably cook up some input files and run it through PDCU5 to see if it behaves like one of the well-known ones (I'm thinking test images consisting of vertical stripes of known values).


However, someone already suggested to try the various methods and do a test print. This doesn't have to be costly - ask your lab for the smallest paper size that is printed on the same machine as your intended 24x26 print and do a corresponding test print of crops from your image with strips using the different interpolation algorithms. Much more practical than worrying about what algorithm does what.

---------- Post added 11-05-17 at 01:10 PM ----------



I was beaten to punch!

---------- Post added 11-05-17 at 01:11 PM ----------



Apparently "Real Zoom" is part of the acronym? Your reason is as good as any, so I'd go with RZT for everything:)
Forum: General Photography 11-05-2017, 09:33 AM  
Macro versus Telephoto lenses for long distance shooting
Posted By BrianR
Replies: 12
Views: 421
This is the conventional wisdom passed on from the photography elders, but I'm not sure how much of a difference this makes since they moved away from inert macro-lens designs. I'm waiting for someone to produce a 300-storey high resolution test chart and do some long distance tests. I'm also waiting for me to get around to doing a distance & close-up comparison between an m42 100mm macro and a dfa100mm.
Forum: Pentax SLR Lens Discussion 11-05-2017, 09:21 AM  
Tamron SP AF 90mm F2.8 Di Macro compatible?
Posted By BrianR
Replies: 16
Views: 507
Have you ever compared them for chromatic aberrations? At or near wide open, the dfa100 can get pretty colorful on high contrast edges. Really my only complaint with it (and a minor one considering the rest of its awesomeness).



Its build is mostly lacking when compared with the WR model, but it's pretty durable overall I'd say:p.



It's a plus and a minus. Deeply recessed protects the front element but it also moves filters further away from it and you usually want them as close as possible for the best results. That said, the raynox DCR-250 is a nice combo with this lens, but I wonder how much of a difference it would make if it was closer to the front element (no, I don't wonder enough to take a hacksaw to mine:D).
Forum: Pentax SLR Lens Discussion 11-05-2017, 09:03 AM  
Full-frame lens on a crop body not advisable?
Posted By BrianR
Replies: 168
Views: 4,518
How about a summary? I'm finding the pattern on his shirt distractingly moire-inducing at the embedding videos size. I suspect he's trying to hypnotize me.

As a general statement, my DFA100mm and FA50/1.4 are parading around as counter-examples of lenses that are pretty darn happy on aps-c. So is my DA*300mm, but this might fall under the 'wildlife' exclusion.
Forum: Digital Processing, Software, and Printing 11-04-2017, 10:06 PM  
Paper Cutter Recommendation
Posted By BrianR
Replies: 8
Views: 388
I do not have a worldly experience with different cutters, but after over a year of hemming and hawing I went with one of the dual rail Rotatrims. Many of the reviews I looked at read like Alex's post above, after disappointment with other brands people end up happy with a Rotatrim. It's somewhat annoying to have suggestions that are above your budget but some things are just worth saving for if possible.

I've had mine for 2 years now, I was pretty impressed with how square it cut and just how thin a strip it can accurately cut off. Trouble free so far and I expect it will outlast me.



Short and Curlies by Brian Robin, on Flickr
Forum: Pentax News and Rumors 11-03-2017, 03:14 PM  
DFA*50 1.4 coming
Posted By BrianR
Replies: 2,051
Views: 151,673
The Laowa hits 1:1, it also covers a FF sensor. It's on my list of 'wants':). I believe most 'macro' zooms of the past have been fairly disappointing compared to dedicated lenses, and I don't think any have been this wide. I don't expect the 11-18mm to be disappointing in anything it's made to do, so I'm doubtful until proven otherwise:).
Forum: Pentax News and Rumors 11-03-2017, 03:00 PM  
DFA*50 1.4 coming
Posted By BrianR
Replies: 2,051
Views: 151,673
I really want to believe this:D. My spare change goes into a jar earmarked towards a (currently) non-existent "DFA*200mm macro". An 11-18mm macro would probably divert this fund. It's probably impossible, but even if it hit 1:1 at the 18mm lens, that'd be something:).
Forum: Photographic Industry and Professionals 11-03-2017, 02:51 PM  
Nikon firing nearly 10% of photo staff and shutting down DSLR lens / compact plant
Posted By BrianR
Replies: 70
Views: 2,240
Yea, I can't afford a K-1 so it all stinks!:p

Seriously though, that kind of functionality is pretty awesome!
Forum: Photographic Industry and Professionals 11-03-2017, 07:24 AM  
Nikon firing nearly 10% of photo staff and shutting down DSLR lens / compact plant
Posted By BrianR
Replies: 70
Views: 2,240
It gets a little more complicated when the small sensor camera also has a variable aperture - take a dfa100mm used on a Q or on a K-1, it stops down to f32 for either camera.

The real way to win with the larger sensor is focus stacking (if applicable to your subject). With Olympus leading the way for limited in-camera stacks and larger focus bracketing options (for post-processing) and Nikon following, it won't be long before it's a standard feature in DSLRs across the board and we all have software that lets our DSLR perform as well as a smartphone:D. (I kid, I kid, focus stacking is far more than that).



Indeed, I'd love to be able to instruct the camera to "1)Take photo, 2) adjust focus forward by x units, 3) repeat steps 1&2 Y number of times" to make a home-brew focus bracketing for stacking. Using a Macro for macro? That should be worth a few bonus points?
Forum: Pentax SLR Lens Discussion 11-02-2017, 07:03 PM  
hello, my name is Sly and I am
Posted By BrianR
Replies: 14
Views: 659
Whoah, whoah, woah! You didn't mention deals before. Deals don't count towards your LBA. Known fact.
Forum: Pentax SLR Lens Discussion 11-02-2017, 07:06 AM  
hello, my name is Sly and I am
Posted By BrianR
Replies: 14
Views: 659
I look at this sub-list and ask, with your goals in mind, what couldn't I do with this kit? The biggest 'hole' is an ultra-wide for capturing expansive habitats or wide-angle close-ups, but I'm sure I could manage with 16mm on the wide end if I needed to:).
Forum: Photographic Industry and Professionals 11-02-2017, 06:23 AM  
Nikon firing nearly 10% of photo staff and shutting down DSLR lens / compact plant
Posted By BrianR
Replies: 70
Views: 2,240
The body of the J line isn't much larger than the Q. With the 10/2.8mm lens, the J1 fits pretty comfortably in my jeans pocket. There are a couple of very compact zooms that would also fit the bill, but there isn't a huge lens selection overall and they certainly could have used more compact pocketable options. Auto-focus is blisteringly fast, and it is nice to use. It has some silly design decisions, like the absurd flash system, and the high price on release didn't help. I don't think subsequent additions to the line were priced much lower either.

A bit of a shame to see systems fade away, it's nice to have distinct options.
Forum: Mini-Challenges, Games, and Photo Stories 10-31-2017, 05:28 AM  
Thematic Flickr Explored
Posted By BrianR
Replies: 513
Views: 37,038
Some colourful ice:



An Icy Panoramic Concert by Brian Robin, on Flickr



This is only my 3rd in explore, I did notice they were all panorama type images. I checked out this link on how [they think] explore works and it it turns out my default upload size was below 1600px on the long side and this excludes things, but the panoramas all were larger. I've upped it to match this. I've noticed a drop in requests for hot dates on flickr, maybe this will help.
Forum: Mini-Challenges, Games, and Photo Stories 10-30-2017, 07:15 PM  
Thematic Cocoons, chrysalis, caterpillars and grubs.
Posted By BrianR
Replies: 76
Views: 3,538
Huh, I would have thought Australia would have an abundance of "The 5 deadliest butterflies in the world" or something to that effect:D.
Forum: Pentax SLR Lens Discussion 10-30-2017, 07:11 PM  
How 'Bad' is DAL 18-55 vs Other Options?
Posted By BrianR
Replies: 67
Views: 2,073
I edited my post above:D.

If we can all get in a big debate over the merits of QS and WR he may just spring for the 18-55 that has both to shut us up.:)
Forum: Post Your Photos! 10-30-2017, 07:05 PM  
Macro Some Birefringent Ice
Posted By BrianR
Replies: 6
Views: 258
Thanks everyone! If anyone is interested, I do have more on my website as well as a few details on how they're made and a few pretty sad forays into the world of timelapses... Birefringence Brian Robin



One tries to be accurate:D



Cheers! I've no expectations to sell anything in these small spaces, but the odd one does go:D. In any case, the experience of printing, mounting and framing is always great



Thank you Mike! They definitely brightened up my working space while I was getting things ready!



Thanks so much:)



This I have done:)
Forum: Pentax SLR Lens Discussion 10-30-2017, 06:53 PM  
How 'Bad' is DAL 18-55 vs Other Options?
Posted By BrianR
Replies: 67
Views: 2,073
Flip of a switch, and for me a swear word at my lens for not having quick shift. Quick shift is teh besto with back button focus, you can flop back and forth between autofocus or manual focus with zero effort (though I'm not positive a k50 can be set up this way?). I'd have no hesitation picking it over WR if it was a choice between the two. My non-WR DA18-55mm went through a number of snow falls and light rains while attached to a non-WR k100d, so WR is not something I'm too fussy on. Others may will disagree though:).

However, this one has both and unless it's too much $$$ you don't have to wrestle with the decision SMC Pentax-DA 18-55mm F3.5-5.6 AL WR Reviews - DA Zoom Lenses - Pentax Lens Reviews & Lens Database, possibly affordable used? I don't really know what it goes for:)
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