Messages

316

EOS Bodies / Re: End of the APS-H sized CMOS?

« on: June 29, 2011, 03:12:16 PM »

What if:

Canon were to start making FF sensors with two pixel densities: one very dense (perhaps 32 or 36 mpix) for those 3-4 fps 5D and 1Ds series cameras, and a lower density (maybe 24 or 18) mpix sensor for a 1D series camera.

The lower pixel density FF sensor would give unprecedented high-iso performance and allow huge fps.  It'd be great for sports, journalism, things like that.  It'd be great for video too!

Question then is of cost.  Right now APS-H sensors are only put into 1D cameras.  Would it be cheaper for Canon to produce two formats only?  Would a low-density FF sensor cost significantly more than a APS-H sensor with similar pixel count?

Cost of a sensor is relative to the size, pixel count is not important.  Canon has a good white paper explaining this. 

http://www.scribd.com/doc/38542576/Canon-Cmos-Wp

Production costs for a full-frame sensor can exceed twenty times the costs for an APS-C sensor. Only 20 full-frame sensors will fit on an 8-inch (200 mm) silicon wafer, and yield is comparatively low because the sensor's large area makes it very vulnerable to contaminants—20 evenly distributed defects could theoretically ruin an entire wafer. Additionally, the full-frame sensor requires three separate exposures during the photolithography stage, tripling the number of masks and exposure processes.[

True.  But there has to be some savings in mass production?


Right now they can make a 5D2 for less than a 1D4.  Yes I know there's a huge difference in build.  But it goes to show that sensors aren't the only thing determining camera cost.


Another thought: Maybe Canon can't beat Nikon in the high-iso department unless they increase the size of the sensor?

317

EOS Bodies / Re: End of the APS-H sized CMOS?

« on: June 29, 2011, 12:29:11 PM »

What if:

Canon were to start making FF sensors with two pixel densities: one very dense (perhaps 32 or 36 mpix) for those 3-4 fps 5D and 1Ds series cameras, and a lower density (maybe 24 or 18) mpix sensor for a 1D series camera.

The lower pixel density FF sensor would give unprecedented high-iso performance and allow huge fps.  It'd be great for sports, journalism, things like that.  It'd be great for video too!

Question then is of cost.  Right now APS-H sensors are only put into 1D cameras.  Would it be cheaper for Canon to produce two formats only?  Would a low-density FF sensor cost significantly more than a APS-H sensor with similar pixel count?

318

Lenses / Re: Why does not Canon have a 50-150 f.2,8 L is and a 150-300 f.2,8 L is lenses.

« on: June 19, 2011, 03:20:54 PM »

I have a Tokina 50-135/2.8.  Optically it's the perfect portrait lens.  It's fairly big and heavy - perhaps slightly heavier than Canon 70-200/4L (both have a 67 mm front element) but way smaller than a 70-200/2.8

Problem with the Tokina is that AF is slow and hunts.  Also there's no IS.  It Canon came out with a ring-USM version plus IS, I bet it'd be popular.  I paid 500 bucks for my Tokina, but a Canon lens with ring-USM and IS would probably retail closer to a grand, I speculate.  Note, the Tokina has been discontinued.  Sigma has a 50-150/2.8.  Going out to 150 mm makes it bigger and heavier.

Sigma also has a 150-300/2.8 OS.  It looks great.  If this is the type of lens you want and you have the dough, then I say go for it:
http://www.photozone.de/canon_eos_ff/629-sigma120300f28oseos

319

Lenses / Re: EF 20 mm f.2,8

« on: June 19, 2011, 03:10:28 PM »

I used to own this lens.  At the time I chose it over the 17-40/4 because I thought I was smart to get an extra stop of light and spend less money.  In hindsight it was a bad decision, I should've gotten the 17-40/4.

It's a mediocre lens.  Color and microcontrast are great.  It's exceedingly sharp in the center from f/4 onwards.  c/a is low.  Has ring-USM focus.  Bomber build quality.  BUT: the corners take a while to sharpen up (f/8) and even then they're not impressive.  Vignetting is high even at f/11.  It's the worst flaring lens I've ever owned (major weakness for an ultrawide).  Bokeh is downright ugly (no big deal).

As mentioned, don't bother with this lens if you're shooting crop.  The cheaper Tamron 17-50/2.8 blows it away in terms of sharpness, plus it zooms.  20/2.8 was way more fun with film.  Even then I should've gotten the 17-40 because 17 mm is more fun than 20 mm.

Maybe they'll update the 17-40/4 someday?  Hopefully not, because that'll probably entail a price increase.

320

Lenses / Re: Canon Announces EF-S 55-250 f/4-5.6 IS II

« on: June 14, 2011, 12:58:56 PM »

Post here from someone who actually owns a 55-250 and shoots a lot with it.

It's one of the great bargains in the Canon lineup.  250 mm, 300 grams, 300 bucks.  Great lens for travel and hiking, stuff where every gram counts.

AF is buzzy but fast and accurate in strong light.  On a 7D in servo mode I had no trouble at all keeping up with fast skiing action.  But indoors or if the light is flat, forget it.  This is a function of aperture, not the type of focus motor.

Sharpness is impressive given the price of the lens.  It's the only consumer telephoto lens I haven't been disgusted with.  And trust me I've tried quite a few over the years.  It's not quite as good as my 200/2.8 L, but it's close.  Even wide open the shots can be printed quite large, and withstand strong cropping.

Bokeh is not bad at 250 mm f/5.6.  Circular and nice distribution of light.  55 mm is not bad either, but the intermediate focal lengths give doughnut shapes.  Once you know this limitation you can work around it.  This isn't a primo portrait lens, but it isn't meant to be either.

Build quality is cheap.  But it's adequate.  The plastic mount only has to support 300 grams.  If you put it in a padded bag it'll survive months of backpacking, no problem.  I do a lot of backcountry skiing and I find plastics easier to deal with in extreme cold.  FWIW on one day at -30C/-20F plus snow my Tamron 17-50 autofocus motor seized (lens shot fine in MF, motor unseized once warmed up) but the 55-250 kept on ticking.

Looks like Canon's announcement is just a cosmetic change, like the 18-55 mk2 announced earlier.  Nothing to get excited about, nothing to get upset about either.

321

Canon General / Re: APS-C 11mm f/2 Patent

« on: April 05, 2011, 12:01:07 AM »

I wonder if it has a bulbous front element.

322

Canon General / Re: Canon 7D noise observations

« on: April 04, 2011, 12:47:53 PM »

Interesting shooting birds with a 7D 85/1.2 neuroanatomist

The 7D makes me rethink where the weakness of AF lies.  I used to think it was mostly the lens, but a good camera makes a huge difference.

The other day I was shooting skiing action shots with my 7D and 55-250 IS.  Yes, the lowly kit lens.  The lens had no trouble at all keeping up with the action.  It performed flawlessly in AI servo and one-shot.  Mind you the light was strong and contrast was high.  But still I was very impressed.  I've had similar experiences with my 50/1.8 and Tamron 17-50/2.8, two lenses that aren't particularly renowned for AF performance.

Anyways, please excuse the AF thread drift.  Please carry on with the noise conversation.

323

EOS Bodies / Re: 60D -- been out for 7 months...should I wait for an updated version??

« on: April 04, 2011, 12:22:09 PM »

I'd wait if, and only if, the 60D is useless for whatever you're trying to shoot and you're certain the 70D will have the particular feature that you need.

If that doesn't apply, get the 60D.

324

EOS Bodies / Re: 3 More DSLR's in 2011? [CR1]

« on: March 24, 2011, 11:16:48 PM »

Well if there's any truth to this... then I wonder if Digic 5 is on the way.

The 1Ds4 and 5d3 would then get the new chip, and perhaps also a 7D2.  2012 could see the chip trickle down to 70D and 700D.  New chip, more video capability, probably an increment in high iso.

In theory then a 7D2 could have the same 18 mpix sensor as the 7D, 60D and 600D.

325

United States / Re: 7d

« on: March 23, 2011, 12:24:43 PM »

No, no, no.

The focal length does not change.  Focal length is a piece of physics that's part of the lens design.

Aperture does not change.  Again, this is part of the lens.

Fstop does not change because the previous two items are fixed.  fstop = focal length divided by aperture.

Field-of-view will change because of the crop factor.

Given the same focusing distance, depth-of-field will not change.

Given the same framing, depth-of-field will be greater on the 7D because your focusing distance will be greater (due to the crop factor, you'll have to back up)


I hope that helps.

326

United States / Re: where do you print?

« on: March 23, 2011, 12:17:26 PM »

4" x 6" at Costco or similar.  Dirt cheap, and done on cheap paper with cheap inks.  I don't expect these to last more than 5 years.

8.5"x11" and 13"x19" on my Epson R1800.  Archival quality, but inks are wickedly expensive.  I'm looking into outsourcing.

Photo albums - blurb.com.  I'm very happy with the work they've done.  Looks great and cost effective.

Gallery wraps - I've found a little print shop in my city that does great work at a fair price.  I've only had a few printed up but they're really really nice.

327

Canon General / Re: Canon 7D noise observations

« on: March 21, 2011, 02:54:25 PM »

Sometimes when we look at review sites that show graphs depicting noise, we are missing a critical element: the quality of the noise.

You've spent some time looking at it.  So have I.

My first DSLR (300D) produced really "clumpy" noise.  These were blobs of chroma noise many pixels (say 10) in diameter that were especially noticeable in shadow areas.  These blobs would really show in prints.  I've found no good way to deal with it in processing.  On top of this was the more random-like pixel-by-pixel luminance noise.

I like the noise of my 7D much better.  At 1600 iso the noise is almost filmgrain-like, and color is still pretty good.  Noise is pretty even between shadow and highlight, which IMO gives it a more slidefilm-like look.  At higher iso you start to see some clumps and the pixel-by-pixel noise goes sky-high.  Still works out better in prints, though.

328

EOS Bodies / Re: 60D first Street Shots around New York

« on: March 20, 2011, 11:21:11 AM »

Nice work!   

329

EOS Bodies / Re: Canon Doesn't Need a Compact Camera System

« on: March 19, 2011, 06:30:13 PM »

IMO the most sensible thing to do would be to have an EF-S compatible system, similar to Sony NEX.

Canon would sell more EF-S lenses, and folks with DSLR bodies might be tempted to pick up a mirror-less body as an addition to the kit.

A mirror-less body coupled with plastic lenses like 18-55 would be pretty compact and light.

Now, Canon, let's please see some light EF-S primes!

330

Lenses / Re: More Sigma Primes Coming? [CR1]

« on: March 15, 2011, 03:04:31 PM »

... and I think Sigma would do well to spec a 135 mm prime at f/1.8

that would require filter size in the 8xmm size

Wouldn't 75mm suffice ?

Yes.  In practice you'll end up with a 77 mm filter.

Canon's 135/2 has a filter size of 72 mm.  Same as the 200/2.8