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Messages - Aglet

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Third Party Manufacturers / Re: Nikon 58/1.4 - $1,700!!!
« on: November 14, 2013, 01:43:48 AM »
I've got a few Pentax lenses that test poorly yet produce nice images so it's not always about ultimate corner-to-corner sharpness and low CA.
Still, however good this new 58mm is, I'll be hard pressed to buy it to get just a little more something from it over my old 50/1.4.  UNLESS I actually need it for night photography where I need the pinpoint lights to look as crisp as they should.

EOS Bodies / Re: New high resolution camera
« on: November 14, 2013, 01:34:28 AM »
You should directly compare the 14-24 corners to canon's 16-35 corners. Sadly (and I own this lens), Canon's corner and edge performance is really atrocious.

Yes, I decided to forego the 16-35 in for the 17-40 instead; was definitely better for landscape type shots from what I saw.

Interesting, that while Nikon and Canon have chosen different paths, the final results are quite similar...

yes, in most cases.

Seems like WA zooms for FF are a weak area, likely difficult to design; I've yet to find a satisfactory WA zoom in the 16-18 to 35-50 mm range.
It looks like the lower end Nikon 18-35mm is winning for performance/cost right now.  Add a 14mm Samyang for that extra wide shot and I can save a bunch of $ as well.

I've got a Tokina 17-35/4 which is very nice from 21-35mm but the 17-20 range on mine is very soft on one side so will be sent in for a warranty tweak.  I also had the Nikon 17-35/2.8.. sharp in center but performance fell off quickly so even on a crop body it had poor corners.
I just got an old Sigma 17-35mm which I've yet to try.
Hopefully Sigma or Tamron will throw their best lens design software at this problem and come up with a better solution soon if the OEM guys don't provide better.

BTW, if you're into astro, I've heard Samyang's 24mm is also good as far as coma is concerned.

Portrait / Re: And yet again...great talent trumps any amount of equipment
« on: November 12, 2013, 11:50:07 PM »
feel free to suggest those to their editor
if they run we'll cut you in for a finder's fee. ;)

Lenses / Re: How many megapixels can these lenses resolve?
« on: November 12, 2013, 11:46:27 PM »
- if some of the lenses are hitting the top end of that sensor - would using a Nikon/Sony 36MP test vehicle let us really see where the lens hits its peak? Until Canon brings out their own high MP body, of course...
Putting a finer resolution sensor behind any given lens will get you a little more total image resolution but gets to be dimishing returns pretty quickly.

Like Pi sez, there are other factors too, mostly what contrast ratio is the bottom end of acceptable for these MTF tests.  You can resolve more if you accept lower contrast.

On Photozone, you can get a bit of a sense of this if you compare the same lens tested on an 8MP 350D vs the 15MP 50D.  If it doesn't max out on the 350d, how high up does it get on the 50d?  It'll likely resolve more LP/PH on the 50d vs 350d but the lense may not be able to max out either of those bodies.
On some lenses the result may be very close or at max on the 350d but will it also be max on the 50d?  If so, heck of a good lens, if not then we're on that diminishing returns part of the curve where the 15MP body may be capable of more.

AA filter strengths and other processing factors also come into play..

So the only thing these kinds of tests, from DxOmark or photozone etc, are good for, is comparing different lenses on the same body if they're evaluated with the same method.  Which, for a given site, is usually consistent enough to be useful for this purpose.
It's a bit of extrapolation to try compare the same lense on different bodies as AA filters and internal camera processing are relatively unknown variables to us.

many grains of salt...

Portrait / Re: And yet again...great talent trumps any amount of equipment
« on: November 12, 2013, 11:28:13 PM »
It always amazes me what kind of images are popular with the masses, even if it's just a fad.
I really gotta get more twisted and come up with some weird cr*p myself.  Shooting technically precise versions of reality may appeal to me and a few others but won't get us on the cover of Rolling Stone.

EOS Bodies / Re: New high resolution camera
« on: November 12, 2013, 02:42:01 AM »
..but the corners are always going to be crap regardless. Buy a Nikon 14-24 and the necessary Canon adapter, and slap that on your ultra high res FF camera to extract the most you can from the sensor, and push that final output resolution as high as possible.

FWIW - I use the 14-24mm Nikon on a D800 on occasion, it's kind of impressive.  but the corners aren't so great for sure, lots of CA and a bit soft.
Really want wide angle high resolution, try the 14mm Samyang prime instead. It's better in the corners at 1/4 the cost.

I'd also like to see DxOmark publish more lens tests using the D800e, the regular d800 is well covered, the e is only published with a few lenses.  AA filter on the d800 is weak but still there vs the e model.

Subjectively comparing center resolution from my long gone 5d2 and 70-200L f/2.8 IS 2 with my d800e with 70-200 f/4 VR Nikon does seem to give a small edge to the Nikon combo but the Canon pair was also providing extremely good detail, especially when using DPP to process it. They'd be hard to tell apart on the same shot, printed at 36"

Third Party Manufacturers / Re: Appeal of Nikon Df
« on: November 12, 2013, 02:20:32 AM »
I suspect the Df is one Nikon body the price might actually drop on in a shorter time frame because of the lacklustre sales.
If it does, I'll be ready to pounce if I still have a paycheck by then.

I've always had a sodtspot for pentax, love their choice of pancakes.  The k-01 is a great looking design too, canon could use some of their design verve.
I thought it was the oddest looking thing when I first saw it.
But once I got it in my hand I found it surprisingly comfortable to use, simple basic controls and soft-controls for many other functions were easy enough to access.  Still haven't had to look at the manual for this one.  The rubber flap on the right side is a bit lame tho.  Fits OK on mine but far too flddly.
A nice, sealed, latching door would have been far more appropriate for a "designer" object.

Lenses / Re: How many megapixels can these lenses resolve?
« on: November 12, 2013, 02:12:23 AM »
The simple answer to your question is as follows:

for any given region of interest, use the table of numbers of LW/PH

take that number, square it, multiply by 1.5 for the 3:2 aspect ratio
divide that by 1,000,000 if you want simple MP and you'll get the equivalent resolution if that portion of the measurement was uniform for the whole frame.

e.g.  center of 17-40 @ f/8 will = ~ 16MP

it's pretty sad when you calculate the corners!

If you measure the top level of the graph, ~3700, you'll get ~21MP which is the MP of the sensor in that body.

Interestingly, under the shell the K-01 is pretty much built from the same components as other pentax DSLRs.  I wouldn't let any fear of repairs in 5 years time stop me buying and enjoying a camera today.
It probably shares a lot with the K-30 which did sell better - and frankly performs about the same functions but also has a mirror and viewfinder - so either one would work as well but the K-01 was available for $150 less when comparing both clearance prices.  I bought a clearance sale K30 also, couldn't resist. It's a very nice consumer grade body with a pentaprism viewfinder and some weather-sealing.

Glad you're enjoying your discovery but it's hard to find any appreciation here for non-Canon, oddball, mirrorless cameras. :)
But you're right, the K-01 is an astoundingly good imaging machine for a really low clearance price.  I like it so much I bought 2 at that deal earlier this year.  Terrific for studio shooting and still-life type work.
I find the display a bit too useless in sunlight, and AF can be indecisive with some lenses.
But you can't beat the image quality from this brick with any Canon cropper!
K-01 has great Hi ISO ability and is also top-teir in low ISO dynamic range and devoid of pattern noise.  IBIS works great too, nearly 4 stops worth here.
I used it the other night to capture some handheld shots, indoors, in very low incandescent light. I was on the floor, watching some TV, when my lady's new red shoes caught my eye.  They made a nice focal point amidst the other colors and textures when she dropped everything right there. Old 18-55mm kit lens.
Light was one frosted 40W tungsten bulb about 15 feet away.  Shot was still underexposed so pushed jpg a bit.

OOC jpeg, EXIF below:

Color Space: sRGB
Contrast: Normal
Custom Rendered: Normal process
Date Time Digitized: 2013:11:09 21:32:57
Date Time Original: 2013:11:09 21:32:57
Exif Version: 2.3
Exposure Bias Value: 0.3
Exposure Mode: Manual exposure
Exposure Program: Aperture priority
Exposure Time: 1 / 5
Flash: Flash did not fire, compulsory flash mode
FlashPix Version: 1.0
FNumber: 5.6
Focal Length: 35
Focal Length In 35mm Film: 52
ISO Speed Ratings: 6400
Metering Mode: Pattern
Pixel X Dimension: 900
Pixel Y Dimension: 596
Saturation: Normal
Scene Capture Type: Standard
Sensing Method: One-chip color area sensor
Sharpness: Normal
Subject Distance Range: Macro
White Balance: Manual white balance

anyone else see the MTF charts here on Tamron's Europe site?  Any thoughts??

that's a pretty big discrepancy in 30 lp/mm curves between sagittal and meridonal at the long end as you go away from center.
Doesn't that make for some annoying aberations and grungy transition bokeh?
Despite that, will wait for some tests to see if it outperforms my old 100-400. If so, then the last "L" in my quiver might hit the market.

Third Party Manufacturers / Re: Off Brand: Nikon Announces the Df
« on: November 07, 2013, 01:57:07 AM »
Just wait until your fore finger needs to reach up and press the shutter button...

color me different then, I prefer a top-deck SR button to the forward angled ones near the front of grips of most cameras today.
However, until I wrap my mitts around a real Df I can't say for sure how well this particular model will fit my hand.  Various photos I've seen makes me think there's a good chance I will like it.

What I'm already sure I won't like is apparently (somewhere I read that) the little PASM mode dial needs to be LIFTED to be turned! If true, that's daft!
The button locks for the other dials should be easy enough to manage with one finger but it's gonna be next to impossible to change mode without taking that camera away from your eye and using both hands with some effort. It should just be a stiffly detented click-stop movement with PASM indicator in the viewfinder.  I don't like how this part works, I regularly switch between A and M.  This would slow me down a bit too much.

Third Party Manufacturers / Re: Appeal of Nikon Df
« on: November 07, 2013, 01:33:59 AM »
Love it, might buy one, Canon can't make one like it.

the comparison shows me something else I've discovered, to my chagrin.
Identical exposure settings produce darker images from Pentax than from CaNikons.
I constantly have to +EV my Pentax when shooting in daylight. Not so much indoors.

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