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Messages - AlanF

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166
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!

167
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.


168
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

169
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.

170
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.

171
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.

172
Animal Kingdom / Re: Show your Bird Portraits
« on: June 21, 2014, 10:11:00 AM »
I concede - tripods are useful.

173
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.

174
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.

175
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!

176
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.

177
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.

178
Software & Accessories / Re: Gimbal head or not for Tamron 150-600
« on: June 18, 2014, 02:59:30 AM »

If you say you do not need IS, then I believe you and salute your rock solid arms and their strength. However, not everyone has your natural stability. Here is what Bryan from TDP, writes, and he claims to work out regularly with weights.

http://www.the-digital-picture.com/Reviews/Canon-EF-600mm-f-4-L-IS-II-USM-Lens-Review.aspx

“I relied on IS a lot when using the version I 600 L IS lens - especially when shooting wildlife. I didn't handhold that lens a lot due to its shoulder/back injury-inducing weight, but the tripod-sensing IS system was quite helpful in reducing vibration (including from mirror slap) when shooting from a tripod. Handholding the 600 L IS II is much easier and I am now relying on IS much more frequently to help me get the shot. I find IS to be an extremely valuable feature for this lens.”

For what it's worth I have arms like pipe cleaners and can barely do a push up!
Though a lot of it is down to technique, not strength, most people can support large lenses surprisingly well for short periods. Locally there is quite a petite lady who rarely uses a tripod with her Nikon 500 F4 + D4 - so it can be done!
My problem with IS is that it slows things down, when you have a small bird flitting here and there I have enough trouble keeping up with it - let alone the IS slowing things up! Try it for yourself. Also I believe that IS is not effective at shutter speeds of less than 1/500 sec so it is of limited use for many subjects.
I should state that I use a 1DX and it's ISO capabilities are a significant part of the equation, were I using a different camera this may alter my opinion.
However, regardless of the camera used, I prefer to shoot with IS off and only use it when necessary (in desperation in my case!). It is a very handy feature, to have in reserve.

For rapidly moving birds etc, use Mode 3 on your IS - the IS kicks in only when you actuate the shutter, and Mode 3 was introduced precisely for tracking fast, erratic motion.

I don't understand why you write that IS is not effective below 1/500s. there are oodles of published measurements and examples of IS working brilliantly down to 1/10s or so - just look at the lens tests on TDP. The following link explains Mode 3 and states image stabilization at 1/5s for the 600mm f/4 II:

http://www.the-digital-picture.com/Reviews/Canon-EF-600mm-f-4-L-IS-II-USM-Lens-Review.aspx

179
Software & Accessories / Re: Gimbal head or not for Tamron 150-600
« on: June 17, 2014, 12:02:04 PM »
In simple terms, if you have a very sharp lens, then every small blurring event, such as minute camera shake, will be noticeable. If you have a very soft lens, then a minute amount of camera shake would not be noticeable in the overall blur. So, you would be crazy to hand hold a 600mm f/2.8 II with IS off, or more sensibly a 400 mm f/5.6 at a low shutter speed. However, a Tamron 150-600mm at 1/1000s with IS on would not register any camera shake.

As Weixing write there is no wrong or right way, but you can have accessories that are overkill for a particular lens.

I have only used the IS on my Canon 800 F5.6 L IS for a couple of shots this year - all my other shots (both hand held or on a tripod) have been with the IS turned firmly OFF. Why - because I get faster AF and a higher hit rate, especially if subjects move. Given the lighter weight and better balance of the Canon 600 Mk2 (that you quote) + the extra stop of light and it is hardly a chore to use hand held and there is certainly no need to turn on the IS in anything but poor light - my 800mm is not as good in this respect being F5.6. Note I am not a bodybuilder - I am a 55 year old arthritic Diabetic. These lenses are not that difficult to manage!

To the OP.
I do not claim to be an expert, but I have primarily used long (400mm +) lenses for quite a while. When the light is good you can keep the shutter speeds up and manage quite happily without support. IS/OS etc have their uses but are no substitute for a decent tripod + head. If you get cheap support you will rapidly outgrow it and end up spending more in the long run. It's up to you, but I would suggest you get good support from my experience.

If you say you do not need IS, then I believe you and salute your rock solid arms and their strength. However, not everyone has your natural stability. Here is what Bryan from TDP, writes, and he claims to work out regularly with weights.

http://www.the-digital-picture.com/Reviews/Canon-EF-600mm-f-4-L-IS-II-USM-Lens-Review.aspx

“I relied on IS a lot when using the version I 600 L IS lens - especially when shooting wildlife. I didn't handhold that lens a lot due to its shoulder/back injury-inducing weight, but the tripod-sensing IS system was quite helpful in reducing vibration (including from mirror slap) when shooting from a tripod. Handholding the 600 L IS II is much easier and I am now relying on IS much more frequently to help me get the shot. I find IS to be an extremely valuable feature for this lens.”



180
Software & Accessories / Re: Gimbal head or not for Tamron 150-600
« on: June 16, 2014, 10:30:59 AM »


Bear in mind that the Tamron is not the sharpest lens on the block, but is sharp enough and provides more fun per $ or ounce than most telephotos. One of its greatest advantages is its light weight and zoom. You nullify these by adding massive expensive gear that might get the best of a supersharp heavyweight that outresolves the sensor but might not increase the sharpness of a less refined lens.

I think we will have to agree to disagree on this point.
Whilst I don't think a 5 series Gitzo is necessary a good Feisol 2/3 series (or similar) with a decent Gimbal would net the best results without spending silly money.
Whatever the price or weight of the lens, it is the focal length that matters. You state that the Tamron is not the very sharpest lens going, surely this makes getting the very best out of it even more important?
If light levels are good then no support is necessary, but that isn't always the case.
[/quote]


Getting the best out of a lens means appreciating what its weak point is. There are mathematical equations to describe the overall resolution of a system in terms of reciprocals of the resolution of the lens, the resolution of the sensor etc. If the resolution of the sensor is low, then it dominates the equation, if that of the lens is low, then it dominates the equation. Under such conditions, the other factors are less important.

In simple terms, if you have a very sharp lens, then every small blurring event, such as minute camera shake, will be noticeable. If you have a very soft lens, then a minute amount of camera shake would not be noticeable in the overall blur. So, you would be crazy to hand hold a 600mm f/2.8 II with IS off, or more sensibly a 400 mm f/5.6 at a low shutter speed. However, a Tamron 150-600mm at 1/1000s with IS on would not register any camera shake.

As Weixing write there is no wrong or right way, but you can have accessories that are overkill for a particular lens.

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