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Messages - raptor3x

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16
EOS-M / Re: EF-M 11-22 / 4-5.6 IS STM - officially announced
« on: June 06, 2013, 12:17:14 PM »
I'm a bit skeptical that the traditional 1/focal length rule applies to these mirrorless cameras with no viewfinder.  I know that when I try to use live view on any of my DSLRs handheld I lose a 'stop' or two of stability due to the loss of the third contact point at the viewfinder.

17
Lenses / Re: Do you wish your 70-200L were black?
« on: May 23, 2013, 12:36:48 AM »
You are ignoring the other ways heat dissipates.

Okay, sure, convective heat transfer could definitely overpower solar radiative heat transfer but you'd need a fairly strong wind to get to the point where a white and black object will have essentially the same equilibrium temperature.  And I doubt conduction has any significant effect in this situation.

Also, once sunlight has heated the object, the radiated heat is at much lower frequencies and the emissivity is more or less the same then (this is somewhere on Wikipedia).

Actually it's quite the opposite, as the object's temperature rises the frequency distribution of the blackbody radiation shifts toward higher frequencies.  This shift toward higher frequencies is what causes the increase of heat transfer out of the body via blackbody radiation.  If it were the opposite, and the frequency distribution moved to lower frequencies as the temperature increased you might have bodies near absolute zero giving off high energy radiation.  It's true that emmissivity will change as a function of temperature and for most materials the emmissivity will tend to increase with increasing temperature, but you're not going to see a white and black object achieve the same emmissivity just by exposing them to 0.1 kW/m^2.

It is a fact that brighter surfaces reach lower eq. temp., not just because the day is too short for them to reach it.

I'm a bit confused here, maybe I'm misreading your statements and if so, I apologize, but you seem to be contradicting yourself.

18
Lenses / Re: Do you wish your 70-200L were black?
« on: May 22, 2013, 07:39:32 PM »
The relationship between colour and temperature of bodies receiving radiation is not as straightforward as 99% of postings on the net say. Although black absorbs heat better than white, it correspondingly radiates heat better. The inescapable consequence is that black and white bodies reach the same temperature when they are in sunlight but black gets there faster.  Conversely, the black body will cool down faster when taken out of sunlight.  So, the Nikon lens heats up faster than the Canon L, but both eventually reach the same temperature and the Nikon cools down faster.


Not true at all.  The equilibrium temperature will vary with the 1/4th power of the emmissivity.

19
And normal shooting sounds like a canon (no pun intended).  This is very disappointing, any suggestions other than earplugs?

I haven't noticed any difference.

20
I'm seeing $779 + ~$16 in eBay bucks.  That's a better price than I've ever seen on the used market.  The only price I've seen lower was during a Canon 20% off refurb sale.

21
Lenses / Re: 300 f/2.8L and 400 f/2.8 at f/2.8
« on: April 14, 2013, 12:32:42 PM »
Could the AFMA be off on the 400?

22
I've shot with Canon cameras my entire life starting with an Elan back in the 90's. A few years back I went digital with a 20D and the FANTASTIC EF-S 17-55 2.8.  The 20D body was destroyed a year or so ago and I've been making do with a Canon point and shoot since then.

My first child is due on the first of May and I want to document his early months with a DSLR. Given my ownership of EF-S glass (really only the 17-55... my other Canon glass is cheap and left over from pre-DSLR days) I think APS-C is probably the way to go; but it bothers me to go after a 7d with its successor just around the corner.

Any thoughts or angles here? I'd only like to spend $2000 and need to do it pretty quickly. I'd like some reassurance that purchasing a 7d at the very twilight of its existence isn't complete folly or maybe an alternative approach I haven't considered (a $1000 EF-S lens was a bit shortsighted of me as I have a hard time justifying FF given the investment).

Buy a used 7D off of FM or PotN, should run you about $750-850; then sell it when the next round of cameras come out.  Will probably end up costing you ~$100-150 for several months of use.  Way way way better than renting.  Also, don't get rid of the 17-55, that lens is fantastic and if it weren't for the fact that I needed a weather sealed normal zoom I would have had a hard time giving it up on the move to FF.

24
I want a 16-35/4 IS (like the Nikon).

This is exactly what I'm hoping Canon will release.

25
That is some shockingly bad background blur at 1700mm.

26
Lenses / Re: DPReview: Canon EF 24-70 f/2.8L II Review
« on: March 07, 2013, 02:23:55 PM »
More high praise for the 24-70 II, with the usual caveat of price.

Question for people who've bought the 24-70 II and had/have the 24-105mm f/4L IS 'kit lens'.  Did you keep the 24-105L, and if so, now that you have the 24-70/2.8 II, do you use the 24-105L any more?

At the moment I've kept both the 24-70 ii and the 24-105 thinking that there were situations where the IS would be way more useful than the extra stop from f/2.8.  What I've found though is that if f/2.8 is not enough, then I'm either shooting something where I'm using a tripod or using the IS of the 24-105 just leads to subject motion, so the 24-105 hasn't seen much use at all.  At the moment I think I'm going to get rid of the 24-105 and replace it with a 35 1.4 instead.

27
Third Party Manufacturers / Re: Good TripodHead
« on: February 27, 2013, 10:19:51 AM »
I'm a huge fan of the Markins ballheads, although the RRS BH-40 is a fantastic option as well.  If you search on FM, you can usually find Q10s going for less than $250.  If you're more budget minded, the Benro B2 or B3 seems to be a reasonable approximation to the Markins, although I don't know how well they'll hold up over time; but I use one of their combination legs (the C4770t) and it's been absolutely fantastic so I don't doubt their ball heads will be any worse.  Then the other issue is that you'll need to start investing in QR plates as well.  When I switched over to the arca-swiss system I ended up spending more on plates than I did on the ball head just because of how many I needed to buy.

28
Have you tried using DPP to do the RAW conversions rather than capture one?

29
Third Party Manufacturers / Re: Canon may be expensive but...
« on: January 29, 2013, 09:44:39 AM »
Dayum

30
Lenses / Re: Ultimate giclée lens?
« on: January 26, 2013, 02:43:22 PM »
Another option would be the Sigma 70mm macro.  That one should be a bit sharper in the corners than your 50 is in the center at F/8 as well as having slightly lower distortion (not that either of these have any detectable distortion.), and less vignetting.  See the photozone.de reviews for more info.

http://www.photozone.de/canon_eos_ff/559-sigma70ff28eosff?start=1

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