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Messages - Plainsman

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1
For Nikon users this will be a very sharp light weight prime capable of stellar performance with a high res body like the D7100 - great for airshows, BIF etc....

2
EOS Bodies / Re: Canon EOS Rebel 750D Spec List [CR1]
« on: January 21, 2015, 11:32:09 AM »
24.2 Mp on the smaller Canon sensor must be equivalent to more than 26 Mp on a Nikon sensor.

It would be revolutionary for Canon to leap ahead of Nikon - so it is highly unlikely!!

3
Lenses / Re: Canon EF 400mm f/4 DO IS II USM Lens Review
« on: January 17, 2015, 03:40:55 PM »
...beautiful short fat lens that would look even better in black!

4
Lenses / Re: canon 7D2 with 100-400 ii lens with 1.4 Extender for birds
« on: January 15, 2015, 03:55:22 PM »
I love the combination of the 7DII, 1.4III and 100-400 MK II for walking around birding. I have said this several times in this forum and have posted shots taken with this combo in Bird Portraits and BIF threads.

With a 1.4TC you need to stop down min half a stop to recover some of the loss of definition inevitable with a TC - so that will be give you a 560/9.5 at best.

Now with all due respect that is hardly a good combo for walking around birding unless you bring a tripod with you.

PS A Tamron 150-600 @600/8 would be better and a lot cheaper - and avoids separating the camera from the lens to install the TC!

5
The MTFs are consistent with those reported by lenstip.It beats out the Tamron wide open at 150 and 300mm, but is very similar at the crucial 600mm - see also the review of the Tamron

http://www.ephotozine.com/article/tamron-sp-150-600mm-f-5-6-3-di-vc-usd-lens-review-23866

at f/8, there is nothing between them at any f. Again, the reviewer complains about the weight.

Here are the MTFs from the ePhotozine site, which is doing brilliantly for rapid reviewing (sigma = upper, tamron lower).
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Why don't they give numbers to the y=axis instead of vague subjective "excellent" etc. and at least say at what distance the "tests" were done.

Distance is important because the excellent nikon rumours test on this lens indicated it was becoming very sharp beyond the usual 40ft test range.

I hate subjective reviews!

6
The resolution MTF curves look exceptionally good - as good or better than the 100-400vII?

Allied to a high res body like the D7100 it should outclass say 7DMKII with 300/4.

But Canon are ahead with their TCs so this lens could be extended to 420 but maybe no further.

7
Lenses / Re: Lens 'resolving power' vs sensors.
« on: January 05, 2015, 07:15:18 AM »
JRISTA, I would just like to say, "THANK YOU" for posting this enlightening info, (and even doing so without a grandiose, self-absorbed ego, I might add). You obviously have a serious optical engineering fund of information. Aside from thanking you, I am posting here so I might be able to search this post again and read it a few more times.  Again, thanks!  :)

I would also like to add my appreciation to jrista for his posts which always include "numbers" in his explanations as well as worked examples.

To many bluffers on this site who have read a book or so and think they are experts on very technical matters.

8
Lenses / Re: Quick Comparison: Canon's new 400mm Options
« on: December 22, 2014, 11:40:03 AM »
I really want to see the in-field performance of the 400 f/4 DO II under different lighting conditions. If Canon has solved the DO weakness of poor contrast and flaring, and knows how to make super-sharp DO lenses, then we should expect to see a 500 or 600 f/4 DO someday - maybe 5.5 to 6 pounds, rather than the 7.0 and 8.5 pounds the version II conventional 500 and 600 f/4 weigh. Yeah, I know - unicorns.

I'm sure its possible, it depends on marketing.  Are there enough buyers in the market to go for a 500mm, a 600mm or a 800mm DO?  A lot of people recently invested a big chunk of money in the new 500mm and 600mm lenses, and are not likely to change to a DO version, so maybe the 800mm is the next DO lens??

I'm surprised you're so sceptical about DO with how much people raved about the weight difference between the Mk1 and Mk2 Big Whites.

My bet is all Mk3 Supertelephoto lenses will be DO, there really isn't much else they can improve otherwise.

I think by 2020 the 500 and 600 dinosaur primes could be replaced by a single 400 - 600/4 DO zoom unit.

Canon are getting the hang of DO now so this would be a natural developement - two for one! Primes are going to be replaced by zooms.

9
Lenses / Re: Quick Comparison: Canon's new 400mm Options
« on: December 19, 2014, 02:14:28 PM »
He must have picked an excellent copy of the original 100-400 for his comparison.  I'd say my version 1 lens is average but the version II lens is excellent.  My copy of the new one is much sharper wide open plus the much improved IS and twist zoom is a "must upgrade" if you use this lens a lot.

They tested four copies of each generation 100-400, and averaged the numbers.

....that's why LR results are more reliable than other reviews where probably only one unit is tested.

10
Lenses / Re: Quick Comparison: Canon's new 400mm Options
« on: December 19, 2014, 09:50:11 AM »
Wow! LR confirms that the 400DO centre is sharper than the new 100-400II by as much as the 100-400II is sharper than the 100-400I. Take that which way you want!

I've always known that my 100-400I was sharp and Roger Cicala's test proves just that. So doubtful whether I will sell it for the newer one now as I never crop at the corners!

BTW this is the first time I have seen quantitative MTF measurements for the old DO - thanks Roger.

11
Lenses / Re: 400mm DO II
« on: December 19, 2014, 07:20:40 AM »
Huge improvement over Mk 1.  The fact that Roger is using new test charts makes it impossible to really compare it to other lenses, but, still, it is significantly better than the 100-400 II and 400 DO I.

http://www.lensrentals.com/blog/2014/12/a-brief-400mm-comparison

I would expect that with Canon's perseverance with DO that this will be a hugely improved ens - I mean a really sharp relatively lightweight 400.

12
Lenses / Re: Canon 100-400 ii Image Quality Review Posted at TDP
« on: December 18, 2014, 12:57:59 PM »
Looking at the crops compared to the tamron. They both look about the same at 400 f/5.6 the canon looks better in the corners at 560 than the tamron does at 600. If I didn't already have the tamron then I would get the canon.

Maybe you should wait for the Sigma 150-600 C version. With more LD lens elements it should outperform the Tamron but would be roughly the same weight and price.

It should be very good in the 400-600 range. We shall see - this time next year!!

13
Lenses / Re: Canon 100-400 ii Image Quality Review Posted at TDP
« on: December 18, 2014, 12:30:41 PM »
Looking at the crops compared to the tamron. They both look about the same at 400 f/5.6 the canon looks better in the corners at 560 than the tamron does at 600. If I didn't already have the tamron then I would get the canon.

Comparing both old and new 100-400@400/5.6 the new version as you would expect is very slightly ahead of the old one in the central region - but really nothing much between them.

Optics is one thing but you also have to consider built in robustness as well and this is where the old one wins with the front lens assembly sliding outwards over a single rigid tube - far better than the telescopic design now back in favour.

14
Lenses / Re: Canon 100-400 ii Image Quality Review Posted at TDP
« on: December 18, 2014, 10:57:21 AM »
I was skeptical that this lens could live up to the hype.  It appears the hype was justified:

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=972

...digital picture quick off the mark.

Looking critically at the crops it seems to me that the Tamron 150-600@600/8 is a tad sharper than the new Canon @560/8. Given the advantage of not having to mess about outside adding/removing TC with ingress of dust etc the Tamron is worth considering - if you want to go beyond 400. Nevertheless this is a fine optic from Canon and for those wishing for a new 400/5.6 forget it - it has arrived in another form.




15
Lenses / Re: EF 100-400mm II - first impressions
« on: December 17, 2014, 02:19:39 PM »
Sorted out the problem why 400 mm seemed soft. The focal length of the 100-400mm at that distance from the target was 370mm, compared with a true 420 for the 1.4x300 with the prime. The smaller focal took the size of the central rings of the chart below what could be resolved. So, I repeated the shots at 400mm (= 370mm) closer to the target so the image is the same size as that from the 420mm. The rings are now very nicely resolved (phew!). Here are the comparisons with my usual procedure. RAW, DxO 10, PRIME noise reduction, exported into PS. On the left there is zero sharpening, on the right 0.9 px at 100% USM.

I am much happier now.


...so at what distance did you actually take your readings?

If the effective focal length is reduced from 400 to 370 it looks as if it is at close range.

8-10 m

I'll check out the focal length at infinity soon.


Thanks Alan but really I would not bother doing an infinity check - its a Canon so its bound to be as stated on the lens!!

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