Canon PowerShot SX70 HS Images and Specifications

AlanF

EOS 5DS R
Aug 16, 2012
4,135
335
#21
Possibly. But nobody ever tried. If the quality was there, and one could use it instead of a telephoto lens of the same price ($1000 range), it could be interesting.
Nobody has tried to market a 250-1500mm 1/1.7" camera for several very good reasons. Firstly, a 24-1500mm would be of the same size (it's the long end that governs the size) and about the same price to make as a 24-1500mm that would appeal to vastly more customers - so why limit your market? Secondly, the niche market, if any, that would use only the very long end would want very high quality, which they wouldn't get with a 1/1.7" sensor (crop factor 4.55, DLA etc) - otherwise why buy such a camera? Thirdly, a 1/1.7" sensor isn't that much of a leap larger than a 1/2.3" in size and quality but it would require a bigger body and lens than a 1/2.3" to give the same f-number and equivalent focal length, etc.
 
Oct 10, 2015
120
0
#23
This is quite a conservative update but I can see a point. It makes no sense to start competing with Nikon on the maximum zoom. If you put some 1500 mm those wanting the maximum would still buy Nikon. It is better to make a balanced package. This is slightly lighter than the SX60 HS at 610 g. Nikon's new P1000 is 1.4 kg.

Size comparison:

http://j.mp/2PVzAht

That 1365 mm is enough for most cases. Air vibration prevents sharp images at very long distances anyway. I find increasing the megapixels strange if they provide cropped 4K.

1/2.3" sensor is 7.7 mm. 1/1.7 " is 9.5 mm. The difference is not that much, equivalent to 0.6 f-stops.1/1.7" sensors are rare now as nobody uses them.

The ratio to the longest pocket zoom is just 1.4x. This is surprisingly little. I recall when I was considering camera in 2011, the ratio was 2.1 x.
 
Apr 21, 2011
236
6
#24
The actual SX60 has effectively 247mm at f6.5. This is equivalent to 1365mm at f36 with a crop factor of 5.5. 1500mm equivalent would need a 367mm lens, assuming the same f6.5 fastness would need a 56mm opening, like 300mm 5.6 lens. it would still have a FF equivalent f26.6 fastness and be way above the diffraction limit.

Of course, this camera would be better in by the ratio of the bigger opening and would be more heavy/big/expensive respectively. by reducing the zoom ratio it could maybe be compensated.

But yes, maybe a 6x zoom with 54mm opening and 77mm filter thread could be done, what none of us knows is, how big the market for a pure supertele camera would be, as far as I know, nobody ever offered something like this
 

scyrene

EOS 6D Mark II
Dec 4, 2013
2,283
133
UK
www.flickr.com
#25
Possibly. But nobody ever tried. If the quality was there, and one could use it instead of a telephoto lens of the same price ($1000 range), it could be interesting.
I don't think companies just launch products to test the market - or not the successful ones, anyway. They do market research first. If no company has done it, perhaps that tells us that their research informs them that it's not worth doing?
 

scyrene

EOS 6D Mark II
Dec 4, 2013
2,283
133
UK
www.flickr.com
#27
There are innovative and new things every day. Yet it is most probably covered by the market research...
Lol, sure but I'm just trying to provide a reason why maybe it hasn't been done. Not every bright idea converts into a successful product. Things we may personally desire may be too niche to produce. That's life!
 

AlanF

EOS 5DS R
Aug 16, 2012
4,135
335
#28
To put some numbers on the diffraction limit: the DLA of a 20.3 mpx 1" sensor is f/3.9; a 1.7", f/2.2; and 2.3", f/1.9. Accordingly, an f/6.5 lens will be 3.4x above the 2.3" DLA and the 1.7" 3x above. As far as resolution is concerned, a claimed 1500mm equivalent lens is, in fact, losing about 50-60% of its resolution and you would get just as detailed results with ~half of the focal length and upresolving by 2x in PS. It would be a waste of time have a 250-1500mm zoom on a 20 mpx 1.7" or 2.3" sensor unless you just want a large image for video or staring through the viewfinder. The SX70 HS is f/3.4 at the wide end, where diffraction will degrade the image less, and the wider aperture wide end is where the camera is best, and it would be crazy to market a 250-1500mm f/6.5 zoom on a tiny pixel camera.
 
Last edited:
Likes: tron

crashpc

EOS Rebel T7
Jan 19, 2014
355
5
#29
AlanF
I know that you´re partially right, as With my powershot G15, I found that with f/4.5 or smaller, the detail was crippled. But not enough so the zoom could not bring more detail. There must be some math behind the zoom vs diffraction function saying that the zoom gains more than what diffraction takes. Otherwise there would be absolutely NO REASON to have many, if not most zoom cameras. That´s not how it works in real life.
P900 still kills those powershots. The specification of diffraction limit must be quite vague...
 

AlanF

EOS 5DS R
Aug 16, 2012
4,135
335
#30
AlanF
I know that you´re partially right, as With my powershot G15, I found that with f/4.5 or smaller, the detail was crippled. But not enough so the zoom could not bring more detail. There must be some math behind the zoom vs diffraction function saying that the zoom gains more than what diffraction takes. Otherwise there would be absolutely NO REASON to have many, if not most zoom cameras. That´s not how it works in real life.
P900 still kills those powershots. The specification of diffraction limit must be quite vague...
I am afraid you have it quite wrong, the math is absolutely clear, once you go over the diffraction limit there is no gain in resolution if you increase the focal length without increasing the aperture. This has been known to every astronomer using a telescope since the time of Rayleigh, see https://en.wikipedia.org/wiki/Angular_resolution

For example, suppose once you have reached the diffraction limit, you double the focal length and keep the same diameter of lens, the image will be twice as large but the size of what you can resolve doubles so you end up with the same overall resolution.

The good zoom cameras and lenses are designed so that they operate within the Rayleigh criterion. For example, the Sony RX10 III and IV have an f/4 lens that matches the ~f/3.9 theoretical DLA of the sensor. The Panasonic-Leica 100-400mm zoom was panned by Lenstip because its widest aperture is f/6.3, which means that it is over the diffraction limit for M4/3 and has poorer resolution than an f/4 lens. The smaller the pixels on the sensor, the wider the lens has to be, which is why your iPhone X has an f/1.8 wide angle lens. Regarding, the P900 and now the P1000, ePhotozine has just reviewed the P1000 and emphasised how the quality of the image drops as the lens extends beyond an effective 2000mm focal length equivalent. There is no reason to have such a large zoom for the P900 or P1000 in terms of resolution. The reason it kills those Powershots is because the diameter of its lens is much larger than the Powershot's and so its diffraction limit is much better. It would be much better still if it had an even much wider lens and was f/2.4.
 
Likes: tron
Sep 21, 2018
1
0
#31
Finally, 4K, WiFi+BT. Any idea, if the video will be still limited to 15/30 mins? The only reason, I don't use my current Canon for video, is this odd limit. Filming a 10k race (running) doesn't make it to finish with Canon camera :D...