September 19, 2014, 04:07:10 PM

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Messages - rs

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Lenses / Re: New Lens Information for Photokina
« on: August 29, 2014, 09:28:52 AM »
Yes, F2.8 doesn't make any sense. Why don't I use the F3.5 on the kit lens? The difference is negligible. I'll consider buying it if it's F2
Size. If it truly is a pancake, it'll be a much nicer size for the 100D/SL1 than an 18-55
If they can make an F2 for the M, there's no reason why they cannot do the same for EF-S
The 44mm flange distance and 24mm focal length already makes for plenty of complexity to meet the size requirements of a pancake lens. Throw into the retrofocus mix a relatively large aperture, and you've got something even harder to pull off. The M mount with its 18mm flange distance doesn't have such issues.

Lenses / Re: New Lens Information for Photokina
« on: August 29, 2014, 09:08:00 AM »
Yes, F2.8 doesn't make any sense. Why don't I use the F3.5 on the kit lens? The difference is negligible. I'll consider buying it if it's F2
Size. If it truly is a pancake, it'll be a much nicer size for the 100D/SL1 than an 18-55

Lenses / Re: New Lens Information for Photokina
« on: August 29, 2014, 09:06:24 AM »
Who the heck would want a FF lens that only goes to f/5.6 at 105mm? 

For years I've been saying American businesses are under a curse of stupidity.  The Japanese might be under the same spell.  What a waste of marketing and manufacturing time.

PATHETIC if this rumor proves true.

Ok, now come the slavish apologist RemarkS.
There have been one or two standard EF zooms which end at f/5.6 in the past:

As full frame edges towards being more affordable, the demand for such a lens increases. Please remember that 105mm f5.6 on a FF body is the equivalent of 65mm f3.5 on a 1.6x crop.

Lenses / Re: New Lens Information for Photokina
« on: August 29, 2014, 08:35:54 AM »
Great!  Three lenses in which I have absolutely no interest.  Canon is saving me money all over the place!

There are three lenses that interest me right now and, would you believe it, they're all Tamrons!
If Canon were to introduce any three lenses, you can guarantee that a fair share of photographers out there will have zero interest in the products.

Each one of these rumoured lenses, if well executed, could have a great reputation and sales for their segment - regardless of whether they suit my needs or yours.

Lenses / Re: New Lens Information for Photokina
« on: August 29, 2014, 08:32:08 AM »
24-105 - slow FF kit - No, thanks.

An EF 24-105 f/3.5-5.6 IS STM could be an indication FF sensors with DPAF are coming.

It would make sense for a lens like this to become the kit lens for a future cheap FF body with DPAF. 6D mk II, or do Canon have plans to introduce a fourth FF DSLR? Nikon already have four and have a fifth in the pipeline (D4S, D810, D610, DF, and possibly the rumoured D750)

Lenses / Re: Another standard zoom advice topic
« on: August 28, 2014, 04:40:01 PM »
I'll probably get a knee-jerk reaction for saying this, but if you can somehow stretch to both afford and can carry it, the mk II version of the 24-70/2.8 is smaller, lighter (805g vs 950g), and has noticeably better IQ. If cost and weight is an issue, my next port of call would be a white box Canon 24-105.

« on: August 28, 2014, 07:31:19 AM »
If you use a non reporting TC, even a old 10D will autofocus at f/8 with some lenses.  Others do not work.  I've tried in numerous bodies and lens combinations over the years.  The TC you use also makes a huge difference, some work better than others.

Again beside the point, though.

The claims by some here are that AF simply won't work in the circumstances we're discussing: I'm saying that I've got a shed-load of actual personal experience - over a number of years, bodies and TCs - that flies directly counter to the "facts" being stated by these individuals.

Of course there's an element of compromise to this, and of course some combos work better than others; but the fact is that they work, despite these authoritative claims that they simply can't.

The only body I couldn't get to AF at all with a TC and my 100-400mm was the 40D; in fact, I believe I was the first person to break this news, on DP Review.

But others could get AF with that body and a TC using the 400mm f/5.6 prime, so - even there - the blanket "can't work" claim was utterly bogus.

All I'm really saying is this: don't take it as gospel that your camera won't AF at f/8 simply because some "expert" on the internet says it won't. Try it yourself
Before you get too critical of other peoples opinions here on this thread, just take a moment to read what they're saying. It's all identical to your findings, just some are saying the glass is half empty while others are saying the glass is half full. It all amounts to the same thing. AF can and does work with some/many f8 lens/TC combos and f5.6 capable bodies, but it can't be guaranteed to work reliably with every f8 lens/TC combo and every f5.6 body in every typical shooting scenario.

« on: August 27, 2014, 07:03:55 AM »

Will a 60D do?

If there is sufficient of light then then 60D might do that, just as the 7D or the 70D could do it over there. there is however no guarantee that you can do it from Canon, as it is not build in in the design of the camera. I am not aware which firmware this even might block, but I think Canon could have done this. Did you look at the quality of your link to digital picture? even in the center the sharpness is gone when you compare the 560mm with the 400mm.
This combo is f8 wide open at the long end. Due to the pixel density of the 60D, diffraction starts to limit resolution at f6.9, so smaller apertures don't have much scope to tidy up the already quite bad resolving power of that lens/TC combo in the centre.

There are no rumours of the hardware in any of the existing Canon crop bodies being capable of autofocusing at f8, so as far as I know there is no possibility of a firmware update for a 60D, 70D or 7D to allow for this feature. There's nothing stopping you from manually focusing it, trying out AF through live view, or even taping over the extra pins on the TC to trick the camera into attempting autofocus.

However f8 autofocus on the 7D mk II is a distinct possibility, even if the rumoured pixel density will mean apertures smaller than f6.6 will run into resolution limiting diffraction.

« on: August 27, 2014, 05:50:56 AM »
Yep, fully aware of that, but it's beside the point: I'm letting people know that despite suggestions to the contrary, both the 7D and the 70D will work in circumstances which some on here have stated they won't work in.

But you need to use then a third party extender for fooling around the body concerning available max aperture. My opinion, the Canon extenders still deliver the best quality on Canon lenses. So, I would like to see a photo of the 100-400 + 1.4 extender on the tele end and taken on a 7D or 70D, as I have my question about IQ at that moment.
Will a 60D do?

« on: August 27, 2014, 03:06:06 AM »
Just some Real World experience to add to the mix: the 7D will AF usefully quickly for bird photography at f/8 (eg Canon 100-400mm and taped or non-reporting 1.4x TC) off the central AF points. Use it on the peripheral points, and it's actually not bad at all.

For example - 600mm, handheld, (Kenko non-reporting 1.5 TC), peripheral AF point on the bird's eye.

And another.

The 70D (mine, and that of at least two other users that I asked to test this) will AF at f/8. Again, it's not lightning fast, but it works.
The hardware may be capable in certain situations of working, but if the central AF point doesn't function, or the reliability doesn't meet the manufacturers stringent testing standards, it's much simpler for them to simply mask out this borderline operation via the firmware.

« on: August 26, 2014, 05:53:02 PM »
Almost all DSLR's autofocus only functions when the lenses aperture wide open is f5.6 or brighter. It's for the same reason that slow lenses make the split prism focus screens on old manual focus SLR's go black.

Being able to AF, even with limited AF functionality with lens combos as slow as f8 was the preserve of the 1 series for canon shooters until the 5D3. Think of a 600/4 with a 2x TC, or a 100-400 with a 1.4x TC.

Your 20D focus issues will be unrelated. It will only attempt to AF with f5.6 lenses (or brighter). If it consistently misses, that's likely down to a problem (calibration or otherwise) with your lens or body.

Pricewatch Deals / Re: Placing an order today (I think) - need advice
« on: August 26, 2014, 03:23:30 AM »
The 70-200 II is optically close to perfection, and takes TC's remarkably well, even the 2x. However, the 1.4x and 2x mk III TC's won't physically mount together. You'll need an extension tube (so you'll likely lose infinity focus), and the camera won't get the correct info about focal length or aperture reported to it.

Also the optical degradation will be significant. You'd be better off using the 2x TC and cropping in post if such a narrow AoV is required.

I guess one big question is:
Which will give better resolution, putting the 70-200 2.8 mk2 on a 70D body with the 1.6x  20.2MP crop sensor APS-C, or putting a 2x Mk3 teleconvertor on the 70-200 2.8?
Not quite a 6D or a 70D, but a 21MP FF (1Ds3) and an 18MP crop (60D), both with the lens and TC you requested:

Lenses / Re: A New Pancake Lens? [CR1]
« on: August 23, 2014, 07:38:50 AM »
The 44mm flange distance makes a non retrofocus (ie pancake) 24mm EF or EF-S lens unlikely.

EOS Bodies / Re: Are These The EOS 7D Mark II Specifications?
« on: August 22, 2014, 05:58:48 PM »
I've seen the results from the 800E, and they are stunning in terms of detail out-of-camera. For nature photography, you don't really need an AA filter.
What's the point in a camera which can produce (in your eyes) better pictures in one particular scenario, while other scenarios are plagued by a design flaw?

Also, what about any nature shots with repeating patterns around the sampling frequency? Uniform vegetation such as some grasses or leaves, bird feathers, animal hair etc?

What you gain is false information. False sharpness. False detail.

Low pass filters are used in all forms of sampling to avoid aliasing. Aliasing is nothing but artefacts. If you can't excite aliasing due to oversampling, there is no gain to be made by avoiding a low pass filter.

Computers have for some time used anti aliasing to improve the percieved resolution of displays - this avoid the jagged edges, false details and create more realistic renderings.

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