walang_pangalan

If you tape over the contacts, the lens is blind to the teleconverters existence. So, when the camera asks the lens, it's to be expected it will return a "f/5.6" which is then displayed.

 

Of course, when you do this -- trick the camera to think an f/8 optic is really f/5.6 -- and then try to AF and it doesn't work well, you just be thankful the camera doesn't explode! ;-) I suspect though you'll find cases where it does work; my 1D2 will AF at f/11 with a subject against a clean background.

1. You shouldn't have bought that 18-55 "kit lens". Next time, just buy the body.

 

2. You should buy the 17-40 to replace the 18-55, and probably a longer 100mm+ zoom of some kind.

 

3. If you can perceive, even faintly, that you'll own a body that does not accept the EF-S optics, you shouldn't buy EF-S lenses.

 

As Rainer T has noted: you need more experience before you act on any advice you receive in this forum. The money will still be in your bank account in a few months... (right?)

Quantum has something called a "Turbo AC", which appears to do what you want.

 

Be prepared for some sticker-shock: http://www.qtm.com

 

The MT-24 is a macro-flash though, so one would expect that the internal AA's would last quite long given the close distances. If, for whatever reason, you need even more than that I'd recommend a larger battery instead of AC. Portability has its uses, even in a studio.

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00KN9Q&tag=

The specks are on the viewfinder's ground-glass. Can-o-air, blower brush, or do what everyone else does: ignore them.

I have no idea where this "7 stops" number is coming from. My usual reference to questions like this are the stuff from Roger Clark:

 

http://www.clarkvision.com/imagedetail/digital.signal.to.noise/index.html

 

wherein he reveals that the DR of Canon's equipment is in excess of 10 stops. And I cite this source because independent tests I have done come to the same conclusion.

<i>If you managed to get droplets of the liquid on certain parts of the camera, you can have permanent damage.</i>

 

<p>Strange: these "canned air" products are used to clean electronics without any noticeable problem. Is your statement backed up with a plausible physical mechanism or actual evidence? Nevertheless, it is important to follow the directions on the can, which usually read "never shake or invert prior to use". It's also a good idea to allow a second or so of flow to clean out any residue before directing the jet into intended use.

Why didn't Canon give the 5D (and friends) that fancy latching shutter on the EOS 3? A good question.

 

Anyways, the ACK-E2 is $60. A 75W inverter -- monster overkill for this application -- runs about $20, and you can just leech off your car's battery. More complicated things exist (fancy gell-cell, car starter, inverter, boom-box, satellite phone, ice maker, masseur, a symphony orchestra, all with the proton precession magnetometer option), but I think you'll be hard pressed to hit even $200 when one is done.

 

If you want to spend hundreds though, you might consider a glorified barn-door tracker: http://www.astrotrac.com appears to be the latest. Well, it's $600 or more. What's an extra $400? (!)

You can see examples of the technique at:

 

http://astrosurf.com/buil/gallery/trails/img.htm

What on earth for? <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00Gtq2&tag=">

The work has already been done.</a>

 

<p>I like the crack in there about <i>"Case closed." Hardly. The dull and ignorant will never understand nor be satisfied with such clear evidence. They will continue to rage unchecked forevermore."</i> I read your bio, Mr. Dickey, and it's abundantly clear you are as far from dull as one can be, but I hope your ignorance re: FF sensors and wide-angle lenses has been cured!

<i>From what I can understand, conventionaly desgned lenses do not have to take into account the angle the light strikes the sensor [...]</i>

 

<P>This is a common refrain throughout the net. As one can expect, it is bogus: every 35mm format wide angle lens is of the <a href="http://en.wikipedia.org/wiki/Retrofocus">retrofocus</a> design and has been for decades. The slight angle of incidence at the corners is a non-issue, be it digital sensor or film. (Simple test: if this AOI effect is real, image quality would not improve as you stop down. No sensor I know of shows this effect; quite the opposite ...)

<i>To me this looks like the same old edge softness that plagues both the 16-35 and the 17-40mm, still apparent on the Mark III.</i>

 

<p>Perhaps this is because that image was collected with the 17-40? And when you do put that Distagon 21mm onto the camera, how good will the image look at 17mm?

I'm going to go out on a limb and ignore Mr. Austin's <a href="

http://en.wikipedia.org/wiki/Selah">selah</a> and make a bold suggestion not on your list: EF 17-40/4L. Put the remainder of your $1k back into the bank and save for the EF 300/4L IS (or whatever).

I dunno, Mr. Uhlig. When I look at fuzzy pictures that I take, I delete them. When I look at those taken by others, I wonder why the photographer didn't delete them. Entropy: it's much easier to blur a sharp image than sharpen a blurred one. Deconvolution works in theory, but usually fails in practice.

<i>it eats through coatings and plastics like cartoon acid</i>

 

<p>Good grief. It is true that DEET attacks some plastics. But the coatings on modern camera lenses are not going to be bothered by the stuff.

<i>I discovered however that the front lens element has two minute blemishes about the size of a tiny grain of sand in the coating.</i>

 

<p>If they are causing problems when the lens surface is illuminated directly by the Sun (or similar), just cover them up with some ink. Otherwise, this kind of micro-obstruction will have basically no visible effect on your images. Indeed, big-time macro-obstructions that cover a third of the objective on mirror lenses or large reflecting telescopes have no effect but for the notorious "donut bokeh".

It's your money. But why are you asking this question after you bought the service?

The most important thing about macro is working distance: you want as much of it as you can. So get the 180/3.5 if you can afford it.

My field observations are that most of the Canon 500/4 or larger are wrapped in something like this (mine does too). The (much fewer) Nikons I've come across were all naked.

 

I got mine for countering the "white lens" effect, but like Mr. Chappell, find it more useful in the anti-bump-and-scratch role. Arguably not worth it for the tripod legs though: pipe insulation works just fine.

Q1 is "What is the difference between ISO 100 and 200?" The answer is "3dB of signal to noise ratio" (I can post graphs, but the data is easily collected on your own). For a well lit scene, in the bright areas, this 3dB isn't easily perceived. Indeed, I frequently use 200 instead of 100 with a 1D2 when the scene isn't very demanding re: dynamic range.

 

Q2 is "How big are film 'pixels'?" The answer is: ~1 micrometre (depending). See http://www.imx.nl/photosite/technical/Filmbasics/filmbasics.html and others. Not only are the 'pixels' smaller, but they are even less sensitive. Hence the observation that while you can get a "more detailed" image with film, this comes at the price of a lower signal to noise ratio. (And bizarro transfer function, lower DR, and so on.)

 

In fact this unavoidable resolution vs. SNR trade-off is at the core of the this interminable debate. Probably the best online summary of this stuff is Roger Clark's writings: http://www.clarkvision.com/imagedetail/film.vs.digital.summary1.html

 

His conclusions will not amuse the "film till I die" crowd...

"Now I would tend to say that Canon should get their lenses right but at least you have some security."

 

And I'm sure that Canon would tend to say that their customers should get their perceptions right, but what can they do? Their repair centers are probably filled with requests from over-anxious owners complaining about back focus problems that don't exist. "But I heard it on the interwebnet!"

Asking what lenses for a particular digital camera is like asking what lenses for Velvia or Astia. The two issues are as orthogonal as Chebychev polynomials. The only thing to avoid is buying a super-expensive camera body and then nickel-and-diming on optics. Not only do you look like a film-era clueless wannabe (blowing his wad on the Nikon F5 and having to slink around in the shadows of a pawn shop for glass), but the return on investment is low -- you'd do better to buy kick-ass optics and use the least expensive camera.

If that's the reason, it's a bad one. The correct solution to the orange LPS glow is to subtract it, not re-scale it. One of many examples available on the net:

 

http://sweiller.free.fr/JTocT_US.html

That's a typical cycle time for in-flash AA's. Better performance is available; alas, at a price:

 

<p> http://www.digitalcamerabattery.com/

<p> http://www.qtm.com/

I perceive no question here. The writer can check out:

 

http://en.wikipedia.org/wiki/Rebate_%28marketing%29

 

wherein it is written "The turnaround time is generally four to eight weeks, though some rebates note a period of eight to twelve weeks." I'm guessing that Canon has written the contract so they aren't bound by a deadline.