July 22, 2014, 11:45:46 AM

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Messages - AlanF

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166
Animal Kingdom / Re: Show your Bird Portraits
« on: March 26, 2014, 07:42:49 PM »
I have spent the last couple of days in Hong Kong and have just arrived in Shanghai, where G**gl* is inaccessible. I put the Tamron 150-600mm on a 5DIII through its paces under conditions where I could get really close. Here is a selection from a morning's shooting. All have been reduced to 1200 px width for uploading, each with a 100% crop so you can see the original.

The processing for all has been the same. Taken in RAW, processed in DxO with the only changes done is noise reduction using PRIME and adjusting exposure (no sharpening). The exported jpegs were cropped in PS and sharpened using USM at 100% with 0.9-2 px radius.

I don't know the names of most so please help me by identifying them (I can't G**gle*, remember).

All are hand held. The first is: Focal length = 350mm, f/6.3, iso 640, 1/320 s


167
Software & Accessories / Re: LP-E6 third party and Canon Chargers
« on: March 20, 2014, 12:52:15 PM »
It does not worry me significantly enough to do anything about it since I have the older charger and so I can use the battery. There is just an annoyance that Canon gets so anal that it does these things.

168
Software & Accessories / Re: LP-E6 third party and Canon Chargers
« on: March 20, 2014, 02:12:10 AM »
A good reason to get the OEM battery despite the higher cost.

I think it is a genuine Canon battery.  When Canon introduced the firmware upgrade that rejected third party batteries several of us experienced problems with what we thought or knew were genuine Canon ones.  It now appears that the so and sos have "upgraded" the chargers as well.

169
Software & Accessories / LP-E6 third party and Canon Chargers
« on: March 19, 2014, 07:25:56 PM »
One of my LP-E6 batteries comes up with an error message that it communicates irregularly with my 5DIii but it still works fine. It charges correctly on my old charger supplied with the 5DIII a year ago. Today, I tried to charge it with the more recent apparently identical charger supplied with the 70D.  It doesn't charge but the charger goes into a rapid red flashing mode.   It looks as if Canon has nobbled it's more recent chargers so as not to work with some 3rd party LP-E6s, and my LP-E6 is not recognised as Canon.

171
Lenses / Re: Thinking about this but wanting your thoughts....
« on: March 17, 2014, 05:27:22 PM »
Waiting for the 100-400 replacement is like waiting for Godot. Either buy the 70-200 or if you want 400mm and beyond the Tamron 150-600.

172
Lenses / Re: Visit Guilin, Mountain Range, in China - Lens selection
« on: March 16, 2014, 03:22:26 AM »
By coincidence I'll be there the following week on vacation, organised as a mystery tour by Chinese friends after official visits to Hong Kong and Shanghai.  I had intended to take the 5DIII plus Tamron 150-600 for nature and 24-105 for general.

 I have been trying to persuade my wife to take the 70D with the 15-85 as it could provide a back-up body and I could omit the 24-105 and we would have two cameras ready all the time.  However, she wants something small for her handbag.  She needs something without any buttons, mode dials etc that can be pressed by mistake and set off the self- timer etc. Anything foolproof to recommend (apart from iPhones etc)?

173
Watch it, Guy. The one in the white blouse is my wife, and you wouldn't stand a chance against her. 

174
Firstly, why do you say dust is flatter than sand? Dust particles are usually modelled to be spherical or cylindrical in scientific studies, ie the same shape as sand and certainly not flatter.


How dust is modeled in scientific studies isn't really relevant to it's ability to penetrate a 'dust-resistant seal'.  Neither dust nor sand are actually spherical or cylindrical, but in general dust is smaller and has a higher surface to volume ratio than sand.  Here's some household dust:



Some of it could certainly be described as 'flatter than sand'.


Neuro
An arrest warrant is being issued for your breaking US copyright.

http://images.sciencesource.com/preview/13250858/BP3016.html

Anyway, I think it is a fake, composed of cabbage leaves, chillies, potato skins and bean pods. As if an SEM gives real colours....

175
Firstly, why do you say dust is flatter than sand? Dust particles are usually modelled to be spherical or cylindrical in scientific studies, ie the same shape as sand and certainly not flatter.


How dust is modeled in scientific studies isn't really relevant to it's ability to penetrate a 'dust-resistant seal'.  Neither dust nor sand are actually spherical or cylindrical, but in general dust is smaller and has a higher surface to volume ratio than sand.  Here's some household dust:



Some of it could certainly be described as 'flatter than sand'.



Are sand particles uniform in size and shape? Aren't some of them flatter and some of them smaller? It is a geometric truism that smaller objects (of similar shapes) have higher surface/volume ratios because volume varies as length cubed and area as length squared. By modelled, I mean that the shape of atmospheric dust particles is determined by their light scattering characteristics, and they usually come out on average as spherical or squat cylinders.

176
You are a professional and need tools commensurate with your profession.

Some of your points are a little odd. Firstly, why do you say dust is flatter than sand? Dust particles are usually modelled to be spherical or cylindrical in scientific studies, ie the same shape as sand and certainly not flatter.

Secondly, you allude to your professional standard lenses as having a gold ring, and the 15-600mm not being in this class. Tamron used the gold ring cosmetically to designate its SP "Super performance lenses": see - http://www.tamron.eu/en/lenses/technology/sp-super-performance.html for a definition of them and their properties including robust outer design.

The Tamron 150-600mm is officially an SP lens: see - http://www.tamron.eu/en/lenses/overview/single/product/sp-150-600mm-f5-63-vc-usd-5.html?tx_keproducts_pi6[cam]=&tx_keproducts_pi6[vc]=false&tx_keproducts_pi6[sp]=false

The last thing I am going to do is to take my lens apart! If it fills up in the next five years with dust like a Dyson, I'll send it it back to Tamron under warranty.

177
The ultimate Tamron 150-600mm, available on eBay for only £1,000,000.

178


That sir is not any old brick wall. That is a genuine Tudor base of a chimney of Trinity College Cambridge, the Home of Sir Isaac Newton, the inventor of, among many other great things, gravity, the prism, the mirror lens telescope, and the founder of modern optics, without which we would not have "glass". Any more comments like that and I will challenge you to a duel of calculus at dawn.

Here is the full frame, showing the glorious base with the Victorian addition or restoration above.


What? I didn't know Newton invented gravity and the prism. I always thought gravity existed before he came along and the prism was a toy/curio which he bought at a county fair.

Before you challenge anyone to a battle of calculus (you failed to name Leibniz), do your homework.


I didn't name Leibniz because I didn't claim Newton invented the calculus (he did, but our German colleagues see it differently - http://en.wikipedia.org/wiki/Leibniz-Newton_calculus_controversy

You don't understand the Cambridge sense of humour (yes, we do have one). My college claims that William Harvey invented the circulation of the blood, not discovered.

If you want a mathematical duel, here is my second (taken on Monday night at iso3200, f/4 24-105)

179
As someone who’s currently building up a collection of kit, I’d like to thank Alan F for his brick wall shots.  I can clearly see that the L glass plus a 2xTC offers better IQ than a third party, 1/3-of-the-price lens. 
I own a Sigma 150-500 and as I have just bought a 70D I’m looking at improving my IQ for keeper’s sake. 
I was considering the Tammy but I now know that I need to go “L”.
Next question is regarding the 300L f4 compared to the 400L 5.6, and just to add further debate, how does the 100-400L stack up against either of these if they had an added TC, and also against the big new Tammy?
I know it’s a big ask but I think it’s valid as there have already been a lot of comments on this thread regarding all these lenses, so if you could make a top ten list of best IQ how would it look???
(e.g. below)
 1st = 300L, 2nd = 300L + 2xTC, 3rd = 400L, 4th = Tammy 600mm, 5th = 400L + 2xTC etc etc, yada yada yada :o
The tamron beats the 300f4L and with the 2x tc it's not even in the same game

Yes. The Tamron is at its best between 200 and 400mm, and really superb at 300mm. It is as good as a good copy of the 100-400 at 400mm, and much better in the corners - it fares well against the 400 f/5.6L over the whole frame. The 400 L is very good with a 1.4xTC, the 300L f/4 is not as good. The 100-400  has crippled AF with a TC, and is f/8. The Tamron has rendered those older lenses obsolete. I am afraid you have to spend 5x more on the 300mm f/2.8 to beat it.

180
I did another comparison of the Tamron 150-600mm @600mm versus the Canon 300 f/2.8 II + 2xTC III on a 5DIII. A Tudor chimney overlooking my garden has very nice detail and shading in the bricks and mortar. In this collage of 100% crops of 800x700, which are testing the resolution at the limits, you can see that the Canon does have the edge, but the Tamron does very well.

I have made a personal decision to never take or comment on "brick wall of shame" crops. Maybe stating that goes against my conviction but I hold fast.

That sir is not any old brick wall. That is a genuine Tudor base of a chimney of Trinity College Cambridge, the Home of Sir Isaac Newton, the inventor of, among many other great things, gravity, the prism, the mirror lens telescope, and the founder of modern optics, without which we would not have "glass". Any more comments like that and I will challenge you to a duel of calculus at dawn.

Here is the full frame, showing the glorious base with the Victorian addition or restoration above.

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