Messages

481

Lenses / Re: will canon make more pancakes?

« on: June 18, 2012, 12:51:27 PM »

What would make more sense for a competitor to the Sigma 30? An EF or EF-s Canon lens?

A fast EF-S.  For EF, the 35L is close in focal length and is already an excellent lens.

Yes but a competitor on price as well.

Canon does not seem to want to compete at the lower price levels with the exception of the 40mm pancake.  Maybe their video lens strategy will be different their their still lens strategy, where every lens revision brings with it a large price increase.  I don't see Canon replicating Sigma's lens line up at the same price as what Sigma offers.

482

Lenses / Re: will canon make more pancakes?

« on: June 18, 2012, 12:14:53 PM »

What would make more sense for a competitor to the Sigma 30? An EF or EF-s Canon lens?

A fast EF-S.  For EF, the 35L is close in focal length and is already an excellent lens.

483

Lenses / Re: Help picking lenses for vacation!

« on: June 16, 2012, 02:52:02 PM »

Thanks so much for the replies! While the vacation is for the family, I would love to take avange of the experiance and taking a lot of serious photos. We are planning on walking for the whole day, so personally the 70-200 is out of the picture. Its just way to heavy to carry for 6+ hours. I will though definitely bring the 35 and 24-105. Also I just recently bought a b&w polarizer. Now that's said and done. Do you think ithe fisheye would be a good add? Not only for the trip but to have in my "inventory" ..

I suggest bringing the 35, 24-105 and the 17-40.  For daytime, I'd bring the 17-40 and 24-105, and for nighttime, I'd bring the 35L.  The 17-40 should work well for buildings and architecture, and the 24-105 would work well for everything else.

The 8-15 is a good add, but not for this trip.  It's best used sparingly and the 17-40 works better as a primary wide angle lens.  That said, the 8-15 is a fun lens.

484

EOS Bodies - For Stills / Re: Canon 35mm f/1.4 L or Canon 50 mm f.1.2 L - for Weddings

« on: June 14, 2012, 07:22:47 AM »

The 50mm f/1.2 L won't focus right with any AF sensor on any 5D. I've tried it on 5Dc, 5DII and 5DIII (and 7D for that matter). My lens, even at the best AF adjustment setting (-20) it misses more often than it hits (stationary high-contrast target from tripod). I wouldn't exclude the possibility of my sample being sub-par, but if you decide to get one of these, make sure the shop has a good return policy. I'd actually recommend getting the Sigma 50mm f/1.4 instead.

Having said that, both the 35mm and 50mm focal lengths are useful for weddings, and the 35L is excellent.

Looks like you should have the lens sent in to be calibrated.  Mine works OK on a 5DII with AFMA.

485

Lenses / Re: 50mm 1.2L + 24mm 1.4L on crop body?

« on: June 13, 2012, 07:50:51 AM »

While your DoF explanation is right, the focal length does not change hence "angle of view of the lens doesnt change either" doesn't make any sense.

What is focal length? Focal length alone doesn't dictate angle of view. Focal length + frame format dictate angle of view. (Simple trigonometry: half angle of view = atan(half frame length / focal length)). When you "crop",  you change angle of view.

You could argue that but the lens still projects FF equiv. angle of view, it's just the outer area of light falls outside the sensor. Well, who cares about the light outside of sensor? The term "angle of view" is always a relative term which really means the angle of view the current sensor is able to see.

That's all I have to say.

Focal length is a property of the lens.  For example, the 14L has a 114 degree angle of view diagonally.  The 50L has a 46 degree angle of view.  To get an object to be the same size with the 14mm lens, you have to be a lot closer, but the angle is still 114 deg.  Try it for yourself.  Take photos of the same object at two different focal lengths and fill the image with the object.  You will see a lot more background with the wider lens due to its angle of view.

486

Lenses / Re: 50mm 1.2L + 24mm 1.4L on crop body?

« on: June 12, 2012, 08:17:18 AM »

Remember, a 50mm lens on a 1.6 might be about 85mm, but you still have the 50mm perspective.

What the heck are you talking about? What's might be a 85mm but have 50mm perspective?

That's the biggest mis-concept ppl have been stating over and over again.

focal length and frame size determines angle of view. Angle of view AND position determines framing. Position alone determines perspective.

Putting a 50 on crop, putting a 85 (approx) on FF, stand at the same position, frame the same picture, the perspective are exactly the same.

Conclusion? 50mm on crop will have 85mm equivalent angle of view as on FF, and will have 85mm equivalent perspective as on FF.

Position alone does NOT determine perspective.  Focal length has a major impact on the relative size of FG and BG ojbects (AOV).  Using a lens on a crop camera is like taking scissors to a print and enlarging it back to the original size.  It does not change the perspective or ratio of near/far objects.  That is why short telephotos are recommended for portraiture -- wide angles tend to empahasize features closer to the camera (i.e. nose).

487

Lenses / Re: He tells me: Compare these lenses and keep any you like!

« on: June 08, 2012, 03:30:42 PM »

What if a second lens needs adjusting? If Canon adjusts camera for one lens, will you lose its adjustment if you re-adjust the camera for a second lens?

Canon would adjust both the body and lens and adjust them toward the ideal setting.  I had a 24L II that was out of focus.  It was covered by the warranty, and I sent it in and Canon adjusted its focus.  I got it back and it worked fine now.  However the note they sent may stated that next time it might be better to send the body in too, so they can adjust both independently and together.

What I am trying to say is if your body is the one that has the tolerance error, then it might require all your lenses to have a AFMA of +15 for an example.  If you got a new lens that needs a +8 adjustment on a neutral body, the closest you will be able to get is +20 (camera limit) but it needs a +23, so your perfect shots would be slightly OOF.  If you send the camera in, then they can adjust it so that it is closer to zero, which would give you the full +/-20 range to make adjustments with.

You can check how well a lens' AF works by taking pictures with phase-detect AF and LiveView.  A good lens would give you similar sharpness across the frame with either method.  A bad lens might give you good LiveView performance, but be blurry with phase-detect AF.  That is what I experienced with a 50mm f/1.4.

488

Lenses / Re: He tells me: Compare these lenses and keep any you like!

« on: June 08, 2012, 02:59:51 PM »

Check with Canon to verify whether or not it is a Canon approved reseller.  If he is not, I would not do business with him.  There are tolerances on all lenses and bodies -- even if your body and lens are both in spec, you could still have to use sizeable AFMA values to get optimal performance.

I would not buy two sets of lenses.  You are taking all the risk because he has your money.  I would get one, try to match it to the body via AFMA.  If that doesn't work, then I'd contact Canon and have them adjust your camera and lens together.  You'd pay shipping once, but then you'd have a well-matched body and lens combination.  Calibrating the body may also make your future lens purchases easier if they are able to "center" the error.

Complete duds are rare.  Finding a lens that is perfectly matched to your body is also rare. 

489

Lenses / Re: 50mm 1.2L + 24mm 1.4L on crop body?

« on: June 08, 2012, 08:05:49 AM »

Yes, L lenses make sense on a crop body.  What you get is better IQ, build quality, consistent AF, and weather resistence, but it costs you money, size and weight.

I've used the 50L and 24L II on my crop body and FF, and they work great.  Increased control over DOF/OOF blur is big reason why people choose prime over zooms.  That said, the DOF/OOF gets a bigger effect when you move to full frame, but lenses retain their value much better than bodies.

490

EOS Bodies / Re: Used 60D or new 650D/T4i?

« on: June 08, 2012, 07:42:45 AM »

I'd go with the T4i.  Even if the sensor is the same as the one used in existing Rebel/60D/7Ds, then it will be a huge increase in IQ compared to a P&S.  The T4i is much more friendly for video users with auto AF.  The T4i is basically a combined HD camcorder and a SLR, which is a good value and it reduces the amount of gear you'd need to do both tasks.

Battery life is so much better for SLRs compared to P&S.  If that concerns you, get a spare or two.  You could also shoot just RAW to increase burst rate according to the spec.  I never use jpgs out of the camera anymore.  Everything goes through LR, which is then used to generate jpgs after all the changes are in.

491

Lenses / Re: Can a UV filter affect IQ (sharpness) on a lens?

« on: June 07, 2012, 10:26:35 PM »

However, I talked to one of my best friends today...He gave me his professional opinion that with current technology (coatings, etc.) the minimum effect on image quality per air to glass interface is 3%.

For example, after 10 filters there would be 73.7% transmission with an optically perfect set of filters (.97)^10 = 73.7%.

Depending on the angle of the light ray passing through the filter, the abberations / MTF deficiency will vary, but once again, 3% is basically a minimum level of effect.

Sorry, going to disagree again. First off, I'm not sure you're distinguishing between transmission loss and IQ decrement. Transmission loss with modern lens coatings is much less than 1% per interface.

Now, take your friend's value of 3% IQ loss per interface leading to a 6% loss of IQ from a filter.  Roger Cicala's (lensrentals.com) tests of large filter stacks refutes that.  Moreover, optically there's no difference between a curved glass-air interface and a flat one - the magnitude of refraction and reflection is the same, only the vector direction differs.  So, let's look at the 70-200mm f/2.8L IS II - arguably the best zoom lens in existence. It has 19 groups, meaning 38 glass-air interfaces. At 3% loss per interface, that means absolutely no light hitting the sensor if you mean transmission, or over 100% IQ loss if you don't mean transmission. I don't think either is even close to true.

The lensrental page below cites that "a modern coating that is 99.9% effective, and total reflection changes to less than 2% for the simple lens and just over 3% for the complex lens." and that "Without coatings each interface would reflect about 4% of the light that reaches it."

http://www.lensrentals.com/blog/2011/12/reflections-on-reflections-the-most-important-part-of-your-lens

492

Lenses / Re: Canon EF 40mm f/2.8 STM Information.

« on: June 07, 2012, 10:21:29 PM »

But why it has to be longer? Cant they bend light sharply enough to use big glass in a very short lens? What are physics restrictions to this? (Just curious , an article regarding this would be an interesting read)

Material properties restrict how much the light can be bent.  To make fast aperture short lenses, you'd need new glass-like materials that have a higher index of refraction and have lower chromatic abberation properties.  Diffractive optics with their gratings can bend light more than traditional optics, but the technology is not yet good enough to deliver comparable or better IQ.

Really? And why can Voigtlander do this, for example? Their Nokton 35mm F/1.4 doesn't look that much bigger. I'm sure there are plenty of others that are fast, in that same focal range and pretty small and flat - and "full frame"...

Isn't the Nokton you cite for a range finder camera, without a mirror box?  What example can you find of a small profile lens that is f/1.4 for a full frame sensor DSLR that also has autofocus?

493

Lenses / Re: Canon EF 40mm f/2.8 STM Information.

« on: June 07, 2012, 12:31:56 PM »

But why it has to be longer? Cant they bend light sharply enough to use big glass in a very short lens? What are physics restrictions to this? (Just curious , an article regarding this would be an interesting read)

Material properties restrict how much the light can be bent.  To make fast aperture short lenses, you'd need new glass-like materials that have a higher index of refraction and have lower chromatic abberation properties.  Diffractive optics with their gratings can bend light more than traditional optics, but the technology is not yet good enough to deliver comparable or better IQ.

494

Lenses / Re: Canon EF 200-400 f/4L IS 1.4X [CR2]

« on: June 06, 2012, 01:37:40 PM »

Unfortunately that's too expensive for most of us ! that's why a new version of the 100-400 L IS is absolutely needed

Yeah, although that too will probably be $2000-2500 if the price increases are consistent.

Even so, it would stilll be a decent value if IQ is improved.  Think of it as combined 300 f/4 IS and 400 f/5.6 primes.  If the resulting IQ is better than those two lenses and the price is a less then the sum, then it'd be a pretty good value with zoom flexibility down to 100mm.

495

Lenses / Re: Looking for travel zoom

« on: June 06, 2012, 12:28:53 AM »

Yeah sounds like sound advice but i will not have any reach for sea world or san diego zoo. Any suggestions. If canon would Release a mirrorless by end of july then i would go that route. I even considered a g1x but have read mixed reviews.

I'd rent the 70-300L and get a sling bag and a harness system that would accommodate your camera and the 70-300L.  For Sea World and the zoo, I would bring only that lens.  For Disney World, I would bring the 24-105L only.  I borrowed a 70-200 and used it for shows at Disney World.  Results were OK, but I didn't use it much.  I wouldn't bother with the 50mm or the flashes unless you have a plan on using it (i.e. night excursions).

I would call wherever you are staying to make sure that there is a secure way to lock the gear while you are out and about.  Just because you're bringing all you gear for a trip doesn't mean that you have to lug it everywhere you go for each and every destination.

The 70-300 non-L weighs about 1.5 lb, and the L version weights about 2.5 lb.  Your 5DIII is about 2 lb.  The 24-105 is also about 1.5 lb.  So that means your camera + 1 lens will weigh about 3.5 to 4.5 lb.  A crop body with a zoom will weigh a bit less, but it's still roughly the same size and it will still impede your range of motion when dealing with kids.  If that is too much, then don't bring the 5DIII and go with a P&S.  There is no point bringing something that you won't even enjoy using.