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new Nikon gear
#1
D5500:

http://www.nikon.com/news/2015/0106_dslr_01.htm

 

 

Nikon is going Canon DO - the new AF-S 300mm f/4 VR PF with Phase Fresnel

http://www.nikon.com/news/2015/0106_lens_02.htm

 

AF-S 55-200mm f/4-5.6 VR II:

http://www.nikon.com/news/2015/0106_lens_03.htm

#2
Here're the specs/MFTs of the 300mm f/4 PF - quite impressive actually

 

http://imaging.nikon.com/lineup/lens/sin...r/spec.htm

 

Makes me wonder whether Nikon will be capable to produce them in volume.  Canon was always a little shy here.

#3
Nice to see them join in the DO/PF. I'm not sure Canon had a problem as such with supply, other than perhaps cost. The 70-300DO wasn't stellar and very expensive, so you have to really want the smaller size/weight compared to conventional designs. Maybe it makes more sense in bigger fast super-tele lenses. Still, would be very interesting to see how Nikon price this lens and if it drives Canon to consider doing more in this area.

 

Edit: I see pre-orders are around US$2000 compared to $1370 for the conventional equivalent, so not that bad.

<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.
#4
The Swiss description reads "FÜLLT DAS BILDFELD, NICHT DIE TASCHE" (fills the frame, not the pocket - EDIT: but that bit could also mean "…not the bag")

 

:lol:

 

Yeah, one gets empty pockets to go with "only 300 mm" at 2000$. That's the price for the Sigma 150-600 Sports. I'd be very curious, if that 300 allows to crop in high quality, then it could be an interesting alternative, especially because of 755 grams vs. 2860 grams (!). My back would like to go Nikon… and my brain would like to try first and buy afterwards  Rolleyes

#5
Quote:Nice to see them join in the DO/PF. I'm not sure Canon had a problem as such with supply, other than perhaps cost. The 70-300DO wasn't stellar and very expensive, so you have to really want the smaller size/weight compared to conventional designs. Maybe it makes more sense in bigger fast super-tele lenses. Still, would be very interesting to see how Nikon price this lens and if it drives Canon to consider doing more in this area.

 
Canon has filed a lot of DO lens patents the last few years, so probably a few designs are in the pipeline.
#6
Looks to be a nice lens, that 300mm f4E PF ED VR. Not only does it "go Canon" with its DO/PF element, also notice the "E" (electronically controlled aperture) The 400mm f2.8 and 800mm f5.6 already got that "E" before it, and those also "went Canon" with FL elements..

 

Funny line from the PR blurb:

"Compared to many general camera lenses that employ an optical system using the photorefractive phenomenon, a remarkably compact and lightweight body can be attained with less number of lens elements."

It does not just hurt the eyes a bit in the language department, but the lens has 16 elements in 10 groups. The old AF-S 300mm f4 has 10 elements in 6 groups.

#7
Well, VR/IS tends to come at cost of extra elements. But yeah, the Canon 300/4L IS has 15 elements.

#8
I'm wondering. Since I've close to no experience with focal lengths at 300 ('sides of the "soso" 28-300, which is crap at 300 mm) and above and am looking currently on "still no delivery date" on the Sigma 150-600, I start thinking about getting this new lightweight lens, maybe a 1.7× converter and save some 2 kg of weight.

 

Any ideas? The weight and size difference is massive and even if the Sigma would bring sufficient image quality between 200 and 400, I'm still afraid it would remain often at home.

 

The converter, on the other side, is something to fiddle with. I had one in the old days and it was always too much to change for only one shot. That would direct me back to the Sigma. But I admit, my patience slowly starts to decrease. Entering the third month waiting, I'm slightly upset. At least, when Nikon announces something new, they usually give a reliable delivery date closely which is end of January in that case.

#9
The lens looks like it's really good. Curious the life is. At the end of 2013 when I decided to try Sony, and then I moved to it, one of the reasons was the absence of an upgrade of the Nikkor AFS 300 f/4, with VR and a lighter design, even though it had been talked about in rumours for months. Had Nikon announced it one year in advance, perhaps they would have kept me as a customer.

 

In any case I'm pretty happy they demonstrated a good 300mm f/4 can be done in such a small and light package. I hope Sony will follow  Smile

stoppingdown.net

 

Sony a6300, Sony a6000, Sony NEX-6, Sony E 10-18mm F4 OSS, Sony Zeiss Vario-Tessar T* E 16-70mm F4 ZA OSS, Sony FE 70-200mm F4 G OSS, Sigma 150-600mm Æ’/5-6.3 DG OS HSM Contemporary, Samyang 12mm Æ’/2, Sigma 30mm F2.8 DN | A, Meyer Gorlitz Trioplan 100mm Æ’/2.8, Samyang 8mm Æ’/3.5 fish-eye II | Zenit Helios 44-2 58mm Æ’/2 
Plus some legacy Nikkor lenses.
#10
The increase in the number of elements can be accounted for fairly easily.  The new lens is just 5.8" long - compared to 8~9 inches for previous lenses.  That gives the lens a telephoto ratio of .466, which is simply stunning and certainly the highest telephoto ratio I've seen on any consumer lens, though there may be higher out there. 

 

Because it's a long focal length lens, it is extremely easy to achieve diffraction limited performance when the telephoto ratio is near 1 - you need very mild curvatures to form the long focal length, and mild curvatures do not produce very large aberrations.  The large airspaces can also be used to correct monochromatic aberrations effectively, the trouble just comes with the polychromatic aberrations.  If one ignores them it is possible to create diffraction limited lenses with focal lengths between 200~800mm in just 2 or 4 elements.  To correct them to an "okay" level can be done in perhaps 5 if one uses CAF2 (fluorite), and 6 if you choose not to, though blue may still be a bit bothersome at that level. 

 

With both telephoto and reverse telephoto lens design, the further the telephoto ratio (over all length of the lens - peak of the front element to the focal plane - divided by focal length) strays from 1 the stronger your aberrations will become.  Often it is said that a telephoto ratio of .7 is superb.  To decrease the telephoto ratio in a telephoto configuration (positive lens in front of negative lens) the first thing to do would be to increase the power of the front group of elements.  Here, absolutely enormous power has been added through the fresnel lens.  Not only does it have a strong focusing power on its own with a short radius of curvature, it looks like it's in the range of 70-90mm, but the fresnel "element" of the lens will add even more power.  All of that power will come at the cost of quite large aberrations.  We can see that the first cemented doublet in the "rear" section of the lens has had its power increase (or decreased one might say, as it has negative power).  The role of this doublet is to roughly collimate the beam of light traveling through the lens, it is aided by additional negative power from the lens just behind it.  The massive increase in positive power up front must be met with a massive increase in negative power, so that single negative lens has had a thin negative lens cemented onto the front.  It likely increases the negative power some while aiding in color correction.  There used to be a meniscus lens cemented to a planoconcave lens making up the focusing group, those have been replaced.  The focusing group is now a meniscus lens cemented to a positive lens.  Behind that is a series of lenses do all many of things - I am not sure which are part of the IS group and which are not but I would suspect that the first three after the focusing doublet make up the IS unit and the following two are just for correction. 

 

Lastly, there is a single positive lens to re-focus the collimated beam onto the sensor.

 

The telephoto ratio is extremely impressive, the extra elements are needed to correct the aberrations you pay with to achieve that ratio.

  
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