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10-16-2013, 07:35 PM   #136
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10-17-2013, 06:04 AM   #137
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QuoteOriginally posted by Digitalis Quote
That is a silver Pentax-L 43mm f/1.9 Special on that camera.

The problem with using RF glass on MILC cameras is that their close focusing distances will always be longer than what is commonly seen on SLR lenses of similar focal length. This is because the accuracy of the Rangefinder decreases as the focus distance gets closer to the 1m mark - a shortcoming SLRs do not have.
We have been close focusing RF lenses on the e-mounts for 2 years with the hawks helicoid adapter, here seen with ZM18


They perform very well at close focus,
10-18-2013, 04:23 AM   #138
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QuoteOriginally posted by uhoh7 Quote
They perform very well at close focus
Of course they work well at close focus! I was pointing out that if they were SLR lens designs they would be able to focus closer because with an SLR you see through the lens - on a rangefinder you can't, which is why focusing errors are problematic as the focus point moves closer to the 1m mark.
10-20-2013, 02:33 AM   #139
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Sony a7 - a set on Flickr

Some A7 shots.

http://www.flickr.com/photos/realityscans/10367426723/in/set-72157636665697086/

10-20-2013, 06:58 AM   #140
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Great. And where to find money?
10-20-2013, 07:14 AM   #141
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Very nice!
10-20-2013, 12:55 PM   #142
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QuoteOriginally posted by Digitalis Quote
Of course they work well at close focus! I was pointing out that if they were SLR lens designs they would be able to focus closer because with an SLR you see through the lens - on a rangefinder you can't, which is why focusing errors are problematic as the focus point moves closer to the 1m mark.
The poster was talking about using the Hawkeye helicoid adapter, which allows closer focusing than the nominal minimum distance by shifting the lens forward.

I have the Hawkeye - it works, but I rarely use it since I don't normally focus that close. But it sure allows crazy thin DOF effects - this is a macro I took using Nokton 50mm f1.1 (nominal minimum focusing distance is 1m, but I was only inches away from the subject)


10-21-2013, 08:14 AM   #143
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From Sonyrumors:

There are still many questions regarding the A7 and A7r features and performance. For example we just learned that only the Sony A7r (36MP) has the offset microlens design. This is very important to know if you plan to use third-party manual rangefinder lenses on your cameras (for example M-mount lenses). And most of you likely didnít know that the A7 has front curtain electronic shutter. So if you still donít know if you should get the A7r or A7 here is a list that mya be helpful:

Pros for A7R
1) A7R is 36 MP while the A7 has 24 MP. Also an advantage if you want to use current E-mount lenses (you get 16MP on the A7r and 10MP on the A7)
2) A7r has missing AA filter which should give you a kick more per pixel sharpness
3) A7Rís sensor has off set micro-lenses designed to better capture light hitting edges/corners (might work better with Leica M lenses) ó A7 sensor does not.
4) On A7R micro-lenses have gapless design. A7′s sensor doesnít
5) Front panel on A7R is magnesium alloy. Itís plastic on A7.
6) Top two dials (exposure compensation and mode dial) on A7R are made from solid aluminium billets. On A7 the dials have rubberized exterior.

Pros for A7
1) Costs $600 less (and best price quality goes to the A7 with 28-70mm kit lens option)
2) A7 has AA filter which avoids major moiree issues and is also great to have if you shoot videos (itís harder to get rid of moire on videos).
3) A7 has front curtain electronic shutter Quieteró A7R does not
4) Flash sync on A7 is 1/250. Itís 1/160 on A7R
5) A7 has on sensor PDAF. A7R doesnít.
6) Continuous shooting: A7 ó 5 fps. A7R 4 fps
10-21-2013, 08:50 PM   #144
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In summary, A7r for those with M-mount lenses and don't care about AF.

A7 for a slightly more usable body with native E mount FF lenses.
10-22-2013, 09:21 PM   #145
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QuoteOriginally posted by Christine Tham Quote
In summary, A7r for those with M-mount lenses and don't care about AF.

A7 for a slightly more usable body with native E mount FF lenses.
Christine, You might want to read the article on Online photographer - sounds like rf type lenses are not optimum for a short registration distance like the A7r, or perhaps its the mp quantity thats the problem.

The Online Photographer: Two Reasons...

[quoteLuke]: "I put my Zeiss ZM 21mm É/2.8 on the A7r we have here [Luke works at Imaging-Resource óEd.]. I'm sad to report that color shifts were severe and covered most of the frame. There was also severe darkening of the image away from the center, way too much to simply call vignetting. I chose this lens carefully, based on the experience of other users, to avoid this problem with my early NEX cameras. It worked well, with visible but very minor color shifts and vignetting. It stayed glued on my NEX-3 for years. Well, I just saved myself a couple grand."[/quote]
10-22-2013, 09:50 PM   #146
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QuoteOriginally posted by philbaum Quote
Christine, You might want to read the article on Online photographer - sounds like rf type lenses are not optimum for a short registration distance like the A7r, or perhaps its the mp quantity thats the problem.

The Online Photographer: Two Reasons...
LOL - sorry I prefer to ignore misinformed opinions and half facts in forums like that.

Roger himself acknowledged that in the real world, the so called issues he discovered may not even be significant enough to be noticeable.

As for the long winded pseudo science in the 2nd reason, a real Leica M9 also exhibits colour shifts for some wide angle lenses, notably the Zeiss. And not just at the edges of the frame either.
10-22-2013, 09:59 PM   #147
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QuoteOriginally posted by philbaum Quote
[quoteLuke]: "I put my Zeiss ZM 21mm ƒ/2.8 on the A7r we have here [Luke works at Imaging-Resource —Ed.]. I'm sad to report that color shifts were severe and covered most of the frame. There was also severe darkening of the image away from the center, way too much to simply call vignetting. I chose this lens carefully, based on the experience of other users, to avoid this problem with my early NEX cameras. It worked well, with visible but very minor color shifts and vignetting. It stayed glued on my NEX-3 for years. Well, I just saved myself a couple grand."
That's a great pity, because that particular Zeiss lens is one reason why the A7 might appeal to me as a future purchase. It's something of a post-facto rationalisation now, but it confirms my decision to not go with the A7, at least not yet. I'll be happy to play with the K-3 for a year or so, while we see what comes up next from Ricoh – I'd be surprised if the present GR was a dead-end, for a start.
10-22-2013, 10:18 PM   #148
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QuoteOriginally posted by RobA_Oz Quote
That's a great pity, because that particular Zeiss lens is one reason why the A7 might appeal to me as a future purchase. It's something of a post-facto rationalisation now, but it confirms my decision to not go with the A7, at least not yet. I'll be happy to play with the K-3 for a year or so, while we see what comes up next from Ricoh – I'd be surprised if the present GR was a dead-end, for a start.
I wouldn't necessarily assume that there is an issue, just because it was reported by one user.

In the NEX pictures thread, there was a discussion about vignetting and colour shift for the CV 15mm lens on the NEX, with some users reporting issues. Yet I see no such issues on my photos, and those users also acknowledged they do not see those issues in the examples I posted.

I need to stress that individual variations in lenses do exist, as well as mount adapters and camera bodies, and a sample size of one doesn't prove anything.

For example, I went through three Summicron 50mm lenses before I settled on one that I liked.
10-23-2013, 12:02 AM   #149
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Another adverse report concerning rangefinder lenses and A7 this time. (previous post was concerning A7r)

http://www.ronscheffler.com/techtalk/?p=224

QuoteQuote:
My take on the results: I’m hoping these lenses will fare better on the a7R. Results on the a7 are for the most part disappointing. All I can surmise at the moment is that the toppings on the a7′s sensor work against achieving optimal (or in some cases, good enough) results with the rangefinder lenses I had available for this test.
QuoteQuote:
Those looking to adapt SLR lenses will probably achieve much better results with the a7 and the new Zeiss lenses look to be quite good, especially the 55. Sure, it’s pricy for an f/1.8 lens, but it looks great right from wide open.
A coupla adverse reports is no big deal - but if this trickle keeps up - i wouldn't buy it for rangefinder lenses.

Last edited by philbaum; 10-23-2013 at 12:16 AM.
10-23-2013, 12:56 AM   #150
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QuoteOriginally posted by Christine Tham Quote
In summary, A7r for those with M-mount lenses and don't care about AF.
While native AF with A7r will not be great, add the Laea-4 adapter, and you can focus alpha glass like lightning. Fast as any DSLR.

I know this because I have the aps-c version of this 350USD adapter with a translucent mirror, the LAEA2. I use it for birds with SAL70400g and nex-5n. Way faster than the native Emount AF. So infact the A7r is much more versatile than a first look at the specs may imply.

If AF is crucial you have two Zeiss Alpha zooms which are as good as anything available--that's my impression anyway.

16-35 2.8
24-70 2.8

I seriously doubt canon or nikon has anything better. equal maybe.

The advantage of the native zeiss 2470 f/4 is form factor and weight.

The FE Zeiss 50/1.8 has MTFs that are off the chart. It may be the sharpest 50 ever made, though Zeiss implies MF lenses better yet in the works for A7r.

I do not care for AF myself, but I will use it for real estate and some events, because it's easier.

QuoteOriginally posted by philbaum Quote
A coupla adverse reports is no big deal - but if this trickle keeps up - i wouldn't buy it for rangefinder lenses.
We already know A7r is fantastic with 50 summilux M, and have anecdotal reports of good results with 28 cron and several 35s. As you may know the M9 and M240 also have issues with various RF wide lenses, so we can expect results to vary with lenses. Brian Smith told me the zm18 has good edges, if true, thats all that matters. Color shift you can deal with post, but not smearing.

In fact, Ron's A7 results are not as terrible as many are whining about, since the edges actually do come into focus stopped down from about 5.6 on with many of his shots. That whole "failure" is way overblown.

Last edited by uhoh7; 10-23-2013 at 01:27 AM.
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