Messages

6301

PowerShot Cameras / Re: *UPDATE 3* Canon PowerShot G1X Revealed

« on: January 06, 2012, 05:15:19 PM »

BTW, my theory is that the "1.5inch" sensor is neither 1.5 inch (that would be almost full-frame, unaffordable at $800) nor 1/1.5" (because that's incompatible with f/16 and "shallow depth of field").

I think it's a 1.5x crop sensor.  That would make it a little bigger than APS-C.  Which would be very exciting.

Shallow depth of field is marketing terminology in this case.  Canon said exactly the same thing about the PowerShot S95 and S100, claiming they were great for portrait photography.  That was with f/2 and a 1/1.7" sensor, so it's no surprise that they would say the same thing about f/2.5 and a 1/1.5" sensor.  As for f/16, what is incompatible about that?  There will be a lot of potential buyers who have not even heard the term diffraction.  It's marketing again - the G12 can be stopped down to f/8, so this would be bigger, and bigger is better.

BTW, a 1.5x crop is APS-C, just not Canon's. Nikon, Pentax and Sony all use 1.5x APS-C.  But don't get excited - the G1x won't have APS-C, it'll have a 1/1.5" sensor.

6302

Lenses / Re: How do I determine if the IS is working on my 24-105L??

« on: January 06, 2012, 04:53:32 PM »

The IS system on your new lens is at least one stop better then the system on your old lens. Also, what camera are you using these lenses with? You should be aware that if you're using a camera with a sensor that's smaller than full frame, you need to multiply the 1/focal length rule by the crop factor to estimate the handholding shutter speed.

FWIW, the IS on the 70-200 II is excellent. The shot below was handheld (free, no bracing) at 95mm with a 0.5 second exposure.


EOS 5D Mark II, EF 70-200mm f/2.8L IS II USM @ 95mm, 1/2 s, f/5.6, ISO 100

6303

Lenses / Re: Recommendation For Long Lenses

« on: January 06, 2012, 03:23:27 PM »

I would leave the 5D II at home unless you will be taking some landscape wide angle shots.  Say with a 17-40mm or 16-35mm.

I'd bring it, as a backup if nothing else.

...I imagine that there are times that the trucks can get closer to the animals. 

Definitely true.  The first image gives an idea of just how close they get - literally within touching distance, at least that was my experience in Ngorongoro Crater.  Sometimes you get even closer...the second shot is my wife and I among a troop of mountain gorillas at Parc National des Volcans in Rwanda.   

Our trip to Africa was 6 years ago...I wish I'd had the gear I have today back then, instead of a 4 MP superzoom P&S...

Bottom line - you'll definitely want a general purpose or ultrawide zoom, IMO.

6304

Lenses / Re: Lens Announcement at CES? [CR1]

« on: January 06, 2012, 02:39:05 PM »

It will be very interesting to see if there will be a 35L II. I want to see how they improve something that is already near perfection.

Weather sealing, for one thing.  It would probably benefit from the newer coatings designed for digital imaging, too, which would give it a slight boost in sharpness.  Of course, the main thing Canon will 'improve' is the profit they make from releasing a new and more expensive version of the lens...   

6305

EOS Bodies / Re: Easiest way to clean.

« on: January 06, 2012, 02:35:02 PM »

Absolutely, yes.  The viewfinder eyepiece is just a piece of uncoated optical glass.  I had thought you were talking about dust inside the viewfinder (which is usually really dust on the focusing screen within the mirror box).  Cleaning the outside is fine.  At need, I've wiped mine free of condensation with the edge of my T-shirt.

6306

Lenses / Re: Recommendation For Long Lenses

« on: January 06, 2012, 02:27:41 PM »

I'd take the 300/2.8 II + 1.4x III over the 400/4 DO - the IQ of the new 300/2.8 even with a TC beats the 400/4 DO lens. 

The 200-400mm with the built-in TC would be ideal...but given that we haven't even seen a formal announcement yet and Canon has still not delivered on the 500/4 II and 600/4 II that were announced back in 2010, I sure wouldn't be holding out any hope you'd actually see that lens by March...perhaps not even March of 2013...

6307

EOS Bodies / Re: Easiest way to clean.

« on: January 06, 2012, 01:25:36 PM »

Looks like reflections?

6308

Macro / Re: Water macro

« on: January 06, 2012, 12:56:25 PM »

Very nice!
Here's mine:

Very nice photo! Fascinating those reflections

Yeah, how did you edit yourself out of the reflections?   

No need - it was at at 5x with the MP-E 65mm, the FoV is smaller than the fingernail of your pinky (the white spots are the reflections of the MT-24 EX flash heads).

Oo, interesting article, been wondering what the speeds were... you wouldnt happen to know the durations for the 430EX II would you? been trying to find articles but havent found any yet...

Sorry, no idea.  I found one post indicating the 430EX II is ~1/520 s at full power, but that post also stated 1/520 s for 1/2 power, and that can't be correct.  I would guess they'll be the same or longer than the 580 for a given flash power, since the 430 has a less powerful flash tube.

6309

Third Party Manufacturers / Re: Nikon's D4 Officially Official

« on: January 06, 2012, 12:03:32 PM »

It did give them time to tweek their marketing approach for sure (focus on weight, F8 AF, etc). 

I certainly noticed that Nikon is highlighting the f/8 AF ability.  But...I'd be very interested to know exactly how they implemented this.  From the published information: "...the D4 maintains the power of the eleven central AF sensors, including one cross-type even if the combined open aperture value is f/8."

There are two possibilties:

• It's the sensor.  They redesigned their 51-point sensor to include additional sensor lines for the f/8 AF, such that the center point is an f/5.6- and f/8 dual cross-type sensor, and the other 10 points have additional f/8-sensitive line sensors.  Canon's previous 1-series bodies had a unique center AF point which had a dedicated f/8-sensitive single-orientation sensor. 
• It's a firmware implementation.  We know that Canon bodies which are limited to f/5.6 will try to AF and sometimes even do reasonably well with an f/8 combination that has pins on the TC taped (or a non-reporting 3rd party TC).  Likewise, 3rd party f/6.3 lenses seem to AF ok on the f/5.6-sensitive sensors.  So, Nikon may have simply tested the AF performance of lenses slower than f/5.6 on the D4, and enabled those points which gave decent results to AF with slower lenses.

Personally, I'm almost positive it's #2.  The subsequent statement in their announcement was: "If the combined aperture value is between f/5.6 and f/8, you even have the power of fifteen central AF sensors available, of which nine are cross type sensors."  I highly doubt the AF sesnor has individual points of differential sensitivity, such that the center cross point has additional f/8 lines, and the surrounding 8 crosses have additional f/7.1 lines or something like that. 

Rather, it sounds like they saw the 1D X announcement with the lack of support for AF, tested the D4 models in development, found that they could get away with implementing f/8 AF for some of the points, slightly-wider-than-f/8 for a few more, and altered the firmware to make those points active with an f/8 lens attached.  Unlike redeveloping the AF sensor, that is something that could easily have been implemented for the D4 in the short time since the 1D X was announced (as could the H3/H4 ISO bumps). 

More importantly, if Nikon's f/8 AF is a firmware implemetation using existing f/5.6-sensitive AF points, it's very possible that Canon could test and then implement something similar, even prior to the actual release of the 1D X.  Perhaps not the same number of AF points, but at least some support for f/8 AF.   Then again, even if they can...will they?  Previously, it made sense as a marketing strategy to drive people to buy longer lenses.  But, from a competitive standpoint, matching Nikon's announced and touted f/8 AF capability may be more important...

6310

EOS Bodies / Re: Easiest way to clean.

« on: January 06, 2012, 11:25:47 AM »

This is on the outside of the VF?  Sure, you can clean it like you would clean any other optical glass surface - I use lens cleaning solution and lens paper (or a pec pad) wrapped around the end of a cotton-tip applicator (a Q-tip would do).

6311

Lenses / Re: A tale of 3 Lenses 70-200 F4 IS vs 70-200 F2.8 vs 70-300 F4.5 IS

« on: January 06, 2012, 11:22:26 AM »

You do know a new 100-400 is coming out? i would wait for that...

Really?  When?   

A new 24-70 was coming out in 2009.  A lot of people recommend waiting for that, too.  Even more people recommended waiting after the CR2 rumor in 2010.  We're still waiting...

6312

Canon General / Re: EOS Announcements in January?

« on: January 06, 2012, 11:12:20 AM »

Although Canon's MTF charts are pretty accurate of late.

Accurate compared to what?   

First off, they are theoretical MTF curves, calculated by computer algorithms using the design parameters for the lens.  They are not empirically measured using actual production copies of the lens.  In one way, that's a good thing, because the theoretical curves ignore QC and copy variation.  But they aren't telling you much about real-world performance.  FWIW, Nikon's MTF curves are also theoretical, but without knowing the algorithms used to generate them, it's meaningless to compare Canon's vs. Nikon's MTF curves.  Zeiss' MTF curves, on the other hand, are real data generated from empirical measurements of actual lenses.   So, the Canon curves are useful for comparing one Canon lens to another, and that's about it.

Second, and perhaps more importantly, Canon's theoretical MTF curves are scaled in line pairs/millimeter (lp/mm) - a useful measure for film, but a more appropriate measurement for dSLRs is line widths/picture height (LW/PH) since it takes sensor characteristics into account.   The fine resolution information (the thin lines on Canon's charts) represents the theoretical data at 30 lp/mm - when you convert that into dSLR relevance, it's 1440 LW/PH.  That value is far lower than the resolution of which modern sensors are capable - the Canon 5DII and Nikon D3X can resolve over 3500 LW/PH. 

So, current cameras can outresolve the theoretical curves.  What does that mean in practice?  When you look at something like the MTF curves for the 400mm f/2.8L IS II, you see that the MTF takes a hit with an extender, but it appears there's not really that much of a difference between the 1.4x III and the 2x III in terms of their theoretical effect on performance.  But when you look at a real comparison between those two conditions using a 21 MP sensor, the IQ hit is bigger than those theoretical curves suggest, because the higher resolution of the sensors is exposing a weakness that the theoretical curves don't show.

6313

Lenses / Re: New official Canon iOS App from Canon Singapore detailing Lenses

« on: January 06, 2012, 10:20:29 AM »

+1, thanks!

I have been using this app:

http://itunes.apple.com/us/app/canon-lenses/id400121928?mt=8

It doesn't have the calculators, etc., but does have links to several reviews for each lens.

Fanboi app? I'd feel like a work-for-free salesperson for Canon

Personally, I feel like someone who enjoys spending time helping others by answering their questions, ideally with detailed, factual information.  But if you'd rather view that as a waste of time or fanboi-ism, suit yourself.

6314

EOS Bodies / Re: Easiest way to clean.

« on: January 06, 2012, 10:17:06 AM »

Where did you blow? Assuming it's inside and not on the exposed glass of the VF where you put your eye, you'd need to blow into the mirror box (lens off, camera off is fine).  Note that you should NOT be in the manual sensor cleaning mode, as the foreign object is above the mirror.

6315

PowerShot Cameras / Re: Making sense of compact camera sensor sizes

« on: January 06, 2012, 07:53:46 AM »

...why can't they just state the height and width in mm!?

Because then consumers could easily compare across models and brands.  Goodness knows, we certainly wouldn't want that...  </sarcasm>

In many industries, specifications are given in non-standard units or relative to brand-specific benchmarks to make comparisons more difficult for consumers.  Marketing departments just want you to believe, "Ours is better - trust us!"