July 22, 2018, 06:38:09 PM

Recent Posts

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41
Landscape / Re: Flowers and other Flora
« Last post by dpc on Today at 09:06:54 AM »
dpc,
Great set of photos of flowers.
-r

Thanks!  :)
42
Sports / Re: Sports from Poland
« Last post by Click on Today at 08:40:22 AM »
Very nice pictures. Well done, Dawid.
43
Lenses / Re: A Bit More About the New Big White Lenses That Are Coming
« Last post by tron on Today at 08:20:56 AM »
As far as clickbait goes :), it would be a certainty that Canon would update the bread and butter 400 f/2.8 and 600 f/4 lenses to function properly with whatever  mirrorless camera is coming out.

I would assume that there are updates to the lens AF motors, possibly the aperture motor to allow more FPS,  internal electronics and communications protocols.

And of course, it is an easy excuse to obsolete upper 4 figure and 5 figure lenses so you have to buy new ones...

Why do you think the current versions won't function properly with whatever mirrorless camera is coming out?  My 600/4 II functions properly with my M6...
+1 Finally some facts. In addition 1DxII fps are more than enough and all lenses cope perfectly with these. Add the fact that the version II tele lenses are firmware upgradeable (although this must be done by Canon most probably) and we have a long term telephoto solution.
44


The introduction of FF mirrorless is a completely different proposition to the M series.

If you think back to the introduction of DSLRs, APS-C was introduced because of the technological challenges of making affordable FF sensors so they introduced a cropped sensor. That cropped sensor had to take the EF lenses already in existence which meant that even when they started making EF-S lenses specifically for DSLR they were constrained on how small they could go in designing lenses.
When Canon introduced the M series, they also took the decision that the new camera did not need to accept EF lenses as native, and this gave them the freedom to design smaller lenses in a smaller mount.

So the rationale behind M series and the FF mirrorless are completely independent.

With both aps-c and FF, key questions would seem to be whether another mount would permit smaller cameras and lenses, and whether smaller cameras and lenses are a good idea.  (The answers might be different for aps-c and FF.)

As far as making lenses smaller goes, you have two parameters that you can play with.... radius and length. The radius at the lens mount is constrained by the FF image circle and can not be made smaller without introducing serious vignetting for longer lenses. Since people go FF for "ultimate quality" this is not going to happen. The size of the large end of the lens is constrained by the F number.... To make the radius (filter size) smaller, you have to be prepared to shoot with a slower lens.... and since the FF market is dominated by those same people searching for ultimate quality, it is highly unlikely that they are going to give up fast lenses.....

That leaves you with one parameter that you can play with, and that is lens length. The problem with shortening lens length is that you are then increasing the angles that light is being bent, and that leads to increased chromatic aberrations, which gives you a poorer quality lens, which once  again flies in the face of the desire for high image quality. There is a caveat here.... and that is DO technology, which can be used to make a lens shorter..... however, for a fair comparison you have to realize that DO technology makes the lens shorter regardless of whatever mount is chosen, so there is no inherent advantage to gained here..

So, if you want smaller lenses, buy slower lenses. Period! Works on all mounts.

Don, I do have a serious question concerning the size of the front element and I'm wondering if that really has anything at all to do with f-stop number. I'm holding in my hand right now a Super-Takumar 50mm f/1.4 full frame lens with a 49mm filter size. I know the lens must be a different type than we have today, but wouldn't f be defined by the size of the hole made by the opening in the blades and light transmission through the glass? This lens is tiny but still has 7 elements in 6 groups. The Canon EF 50mm f/1.4 also has 7 elements in 6 groups, but has a 58mm filter size. I suppose the front elements can be the same size and the bigger body on the Canon has to do with AF mechanicals. I just don't have a Canon 50mm to compare. One thing I know for sure is that these old lenses are very small.

The maximum aperture will define the minimum size the front element can be - or, more exactly, the entrance pupil which is much further back but the front element is a close enough approximation. Manufacturers often make the lens larger for design reasons, among which is the amount of glass to reduce/mitigate aberrations or the selected mount design.
45
rumors for pending Nikon FF mirrorless cameras include specific mentioning of a good AF system. Personally I expect it to be fully on par with Sony A7 III for the lower-end Nikon (2000 usd) and with Sony A9 for the higher-end Nikon model (4000 usd). I cannot imagine Nikon coming out with mirrorless FF duds. It is their most important product launch in a long time. i am hoping for a similar hit as the D3/D700/D300 back in 2007. Canon needs a good wake-up call.

Quote
Over 400 AF points, not sure about the exact number, it should be somewhere between 430-450. The AF is supposed to be very fast.

More magic numbers! 
Read more: https://nikonrumors.com/page/5/#ixzz5Ly1vsoEp

Quote
Over 400 AF points, not sure about the exact number, it should be somewhere between 430-450. The AF is supposed to be very fast.
Read more: https://nikonrumors.com/page/5/#ixzz5Ly1vsoEp
46
As far as clickbait goes :), it would be a certainty that Canon would update the bread and butter 400 f/2.8 and 600 f/4 lenses to function properly with whatever  mirrorless camera is coming out.

I would assume that there are updates to the lens AF motors, possibly the aperture motor to allow more FPS,  internal electronics and communications protocols.

And of course, it is an easy excuse to obsolete upper 4 figure and 5 figure lenses so you have to buy new ones...

Why do you think the current versions won't function properly with whatever mirrorless camera is coming out?  My 600/4 II functions properly with my M6...
47
Patents / Re: Patent: LCD for Image Review While Using An EVF
« Last post by denstore on Today at 06:26:50 AM »
As has already been mentioned, the picture seems to be an old 50D. Buttons in the bottom side of the screen, the on off button, next to them and built in flash. It’s not a new camera.
48


Nikon is pulling a fast one here.
While I've never found a compact superzoom that I was happy with, I wonder if they have any tricks like stacking to recover some of that lost resolution and noise.  I'm certainly not about to run out and buy one.

How can something that is lost be recovered without being refound? You can‘t recover these information, you could only apply some kind of filter to some data and recalculate some possible pixels from it... nothing substantial...
That said, I know nothing about the actual optical performance of this camera...
Stacking allows you to improve resolution and reduce noise over a individual image.  This is a well known way to improve images and reduce noise from a camera.  It does have some limitations though, its no good when movement is involved.  I look at it as a way to recover a image, but really what it is doing is taking bits from a stack of images to get the best of the combined stack.

You are quite right that taking multiple images will increase signal to (uncorrelated) noise (if you take n images, S/N increases by sqrt(n)). If the resolution is limited by noise, then you would improve resolution. Unfortunately, it will not improve resolution that is limited by diffraction, and this has been the bane of astronomers and microscopists for generations. You spurred me to read about this, and I came across the following paper in which the authors claim to have improved resolution by just under a factor of two by very complicated procedures that don't seem practical to photography as yet, if ever. The claim for 3000mm equivalent resolution of the P1000 is still a con.

Super-resolution optical telescopes with local light diffraction shrinkage
, Changtao Wang et al, Nature Scientific Reports volume 5, Article number: 18485 (2015) (free on-line access).
49
Patents / Re: Patent: LCD for Image Review While Using An EVF
« Last post by bitm2007 on Today at 06:13:21 AM »
5D level body (joystick, button layout) with a tilty-flippy screen, hence buttons were repositioned. there is a hinge to the left of the screen.

I am more interested to  know what the switch located on the bottom of the body under those buttons is for? To lock / unlock hinged screen?


....Any ideas why the trash, zoom, play buttons etc are position under the LCD panel ? Those locations look awkward for a moderately sized body to me.

An articulating screen on 5D style camera, that would be a first.  If that's the case I think positioning the buttons on the right hand size of the body or a hinge at the bottom of the LCD screen would be preferable.  If along the bottom, the thumb would need to be stretched over other buttons, which are likely to be pressed as a result.

50
Black & White / Re: Black & White
« Last post by Eldar on Today at 06:11:13 AM »
d
He he, Edward ... 69 is not THAT old ;)

Early this year I went to Lake Kerkini in northern Greece, where the fantastic dalmatian pelican stays over the winter. This one, looking into the sunset, looks like a bird´s version of Lord Nelson.


beautiful image
I'm in admiration of the tonal ranges in these images. is that down to great processing skill and/or really good exposure? I love b&w but mine always look flat to me even after spending an age on curves and black point adjustments.
I am far away from being an expert on processing, so I have to rely on my ability to expose properly. In post processing of B&W images, I primarily play with contrast, clarity and the black and white sliders. On B&W images, you can go a lot further with those 4 than you can with colour. Occasionally I also adjust the colour sliders, if that is required to separate positive and negative space, or create pop.

Very important though, is to use a good and calibrated monitor. I use an Eizo with built in hardware calibration. What I see on the screen is what comes out on my printer.
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