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Messages - AlanF

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46
Here are a few bird photos taken at random. 300mm /2.8 II + 2xTCIII on 5DIII. Usually f/5.6 and iso 640

47
Animal Kingdom / Re: Show your Bird Portraits
« on: June 23, 2014, 09:40:19 AM »
Harpy Eagle, Belize

How did you get that close?

48
Lenses / Re: The sharpness curse!
« on: June 22, 2014, 04:10:35 PM »
Good night Madam
Surapon

My dear friend Surapon, you forgot I'm male (MRS are my initials)- but what's in a name :)

Many people here make the same mistake, so I updated my avatar awhile ago as a hint to my gender ;)

Why do you have 38Ca (isotope of calcium with half life of 440 ms) in your avatar?

49
Lenses / Re: The sharpness curse!
« on: June 22, 2014, 06:18:31 AM »
f/64 on a full plate camera has the same Airy disk relative to its size as f/11 on a FF.
A 210mm lens on a full plate is equivalent to a 50mm on an FF.
The hyperfocal distance of a 210mm at f/64 on full plate is 10.1 m, which means setting it at 10.1 m has everything sharp from 5.05 m to infinity.

A 50mm on FF has at f/11 a hyperfocal distance of 7.42 m. So, everything from 3.71 m to infinity will be sharp.

Yes, Ansel Adams would have loved a 5DIII or 1Dx!

50
Lenses / Re: The sharpness curse!
« on: June 22, 2014, 03:53:31 AM »
Sharpness really isn't critical beyond a certain point, so long as you have the right length lens for the job and have time to perfectly compose the shot.  Where sharpness starts to matter is when you don't have that chance, and you have to crop after the fact.  So basically, I care a lot about sharpness in whatever lens I choose to keep on my camera by default, and I don't care nearly as much about sharpness on the other lenses in my arsenal—except for the long zooms when I'm taking photos of birds; then I care again, because I don't own a $14,000 behemoth lens....  :)

Absolutely right about the superteles. You use them because you can't get close to your subjects, especially birds, and the images have to be razor sharp to allow very heavy cropping. The subject bird typically occupies less than 5% of the frame. Here is a detail of an insect in the beak of a robin I took yesterday. The whole crop is only 356x285 pixels from the 22 Mp full frame. Sharpness might not be necessary for an artistic shot or a portrait, and Cartier Bresson once wrote "Sharpness is a bourgeois concept", but you need the ultimate sharpness for some jobs. With a softer lens that insect would have been too blurred.


51
Animal Kingdom / Re: Show your Bird Portraits
« on: June 21, 2014, 08:13:14 PM »
Love this topic! Awesome eagle shots CT John!


Your last one annotated as "loons" looks more like a cormorant, and is certainly not a loon.

http://www.allaboutbirds.org/guide/common_loon/id

52
Photography Technique / Re: Need advice: 60D + 100-400L
« on: June 21, 2014, 08:06:39 PM »
The 100-400 L also is quite variable in IQ and you might have a bad one. Whereas a good copy of the 100-400mm L is a decent lens, I found it sharp enough only when I got close enough to birds that they filled quite a lot of the frame. So. I invested a fortune in the 300/2.8 II + 2xTCIII to get tack sharp images. I subsequently sold my 100-400 and bought a Tamron 150-600mm for not much more. The Tamron at 600 mm has a real edge over a good copy of the Canon for bird photography.

53
Reviews / Re: Sold all my canon gear . . . Then bought a 70d
« on: June 21, 2014, 01:02:40 PM »
Apologies - I read it the first time and forgot on replying to the second post.

54
Animal Kingdom / Re: Show your Bird Portraits
« on: June 21, 2014, 12:07:30 PM »
Robin with insects. The robin, who personally endorsed my ballhead tripod, has a nest with a couple of chicks in my garage. He is feeding them with a high protein varied diet.

All 100% crops at 600mm, f/5.6, hand held, iso 640-1250, speeds 1/200 or slower. I got within 3-5 metres of him.

55
Animal Kingdom / Re: Show your Bird Portraits
« on: June 21, 2014, 10:11:00 AM »
I concede - tripods are useful.

56
Reviews / Re: Sold all my canon gear . . . Then bought a 70d
« on: June 21, 2014, 05:18:30 AM »
Quote

You do realise, that f/4 on FF is still thinner DoF than f/2.8 on APS-C, right?


This is incorrect. A lens mounted on full frame or crop will deliver the same dof at the same aperture. Ie if you mount a 50 1.4 on a 70d or a 6d both will have the same dof. It's the same glass. But the angle of view will obviously be a lot wider on 6d


According to the Depth of Field calculator you are both wrong.

http://www.dofmaster.com/dofjs.html

The depth of field is thicker for the same lens on FF for a subject at the same distance because the field of view is greater for FF.

57
Lenses / Re: Canon 70-200 f/2.8 L vs. Canon 70-200 f/4 L IS
« on: June 20, 2014, 05:42:58 PM »
As usual, some don't read the original posting. The OP has the the Mk 1 200mm f/2.8 L, not the II with IS. The Mk 1 lens is much poorer optically than the II IS at 200mm. You have to stop it down to f/4 to get it as sharp as the 200mm f/4 L IS. Whereas there is a good case for the 200mm f/2.8 II IS, the f/4 IS beats the older lens hands down.

58
Software & Accessories / Re: Gimbal head or not for Tamron 150-600
« on: June 19, 2014, 06:02:47 PM »
Mack - we could have 300/2.8 II + 2xTC thread, there is now quite a group of us!

59
Software & Accessories / Re: Gimbal head or not for Tamron 150-600
« on: June 19, 2014, 04:23:28 PM »
If we are showing the usefulness of IS, here are two of mine with the 5DIII at iso 2500, taken on the same dull day. The first is a blackbird, 300mm f/2.8 II x2xTC at 600mm, f/5.6 hand held at 1/60. The second is plain ridiculous, a robin in my garage, virtually in the dark: 300mm f/2.8 at 1/13 s, hand held. Without IS it would have been a blur. The blackbird would have been one mess of camera shake.

60
Software & Accessories / Re: Gimbal head or not for Tamron 150-600
« on: June 19, 2014, 03:02:49 AM »
While I can hand hold a 300 f/2.8 ii + 2x TC with IS, I will tell you that using a tripod is better at that focal length.  The Tamron is about 1.5 pounds lighter than that combo but I can tell you that there still are times when a tripod is a great tool.  Having only recently gone to a Gimbal head, I'd really recommend it over a Ballhead unless travel weight is a limiting factor.  I am biased but I like the Lensmaster RH-2 for it's size, simplicity and price.


Art Morris, the doyen of bird photographers, sums up the situation for the 300/2.8 in:

http://www.birdsasart-blog.com/2012/03/07/gear-evaluation-the-canon-300mm-f2-8l-is-ii/

Sometimes you need to hand hold, like for birds in flight, other times a tripod is better. I like resting the lens on a ledge in a bird hide or on wall, tree or pole when walking, and always have a small plate on the tripod foot to stop it being stripped of paint.

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