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09-03-2014, 10:52 PM - 1 Like   #91
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QuoteOriginally posted by ElJamoquio Quote
It takes a rare lens comparison for the edges to be worse on FF than on APS-C at equivalent focal lengths. This is just another myth that won't die.
On another thread in this sub-forum, this opinion was posted:

they wouldn't do it right... it would be just another ovf failure, and canikon already has the market for obsolete ff ovf cameras sewed up.

how many of you people that want ff have pixel-peeped your pentax lenses on a 36mp sensor? guess what, vignetting and field curvature are much bigger issues than you would have guessed.

yesterday i tested five 28mm primes... three of 'em were 28/3.5 lenses, and they were all so dark in the corners that i would rate 'em not usable wide open... we are talking corners down -3.6 to -4.0 stops, in imatest... it was like shooting through a porthole window.

the two 28/2.0 vivitars that i looked at were bright enough, but field curvature made 'em unusable at anything wider than f/8.

be careful what you wish for.


Ain't the Internet wonderful?

Wide angles on FF are just fine. Wide angles on FF are garbage.

Facts?

It is well known that there are issues with certain ultra wide lenses on the A7r in particular- especially those designed for short registration bodies such as Leica M.

It is also known that the performance of legacy wide angles in general on the A7r is widely variable, especially up to 28mm. Some legacy lenses are pretty good, some are not. Some are excellent.

Experience? I bought an A7r 3 months ago, primarily for use with a trio of classic Leica M lenses- early 70s 35/1.4, 50/2.0, 90/2.8. Prior to actually buying the camera, I bought an adapter and tested the lenses on a body. They were all superb. And no, I'm not a Leica fanboi. I've shot Pentax for 40 years. The Leicas are an inheritance that I've used for over 25 years. Gearhead? The A7r is a bit of an upgrade from my K20, I think.

As my main application is for landscape photography with a normal print size of 2x3 feet, for my purposes lens excellence first of all requires great sharpness at mid apertures. Secondly, I expect high flare resistance. Wide open performance is irrelevant. My reason for choosing FF was that I wanted somewhat better detail at 2x3 feet as well as the option of going larger still while maintaining what I judge to be acceptable sharpness. (I'm a retired professional just doing my own thing.)

28mm lenses? I've tested the Super Takumar first version, SMC Takumar 3.5, Pentax K 3.5, Pentax FA AL 2.8, Olympus 2.8 and 3.5- all at mid apertures. The best of the lot is the FA. Very sharp to the corners, excellent flare resistance. It's in a kit with my Leica lenses. Second best, Olympus 28/3.5. Very nearly as sharp as the Pentax, but coatings not as good. Highlights tend to blow out a bit. It's in a backup kit of other very good lenses designated for more risky situations. The rest? Olympus 28/2.8 also pretty sharp including corners, but not quite as good as the 3.5. Also some PF. Pentax K/SMC Takumar 3.5- quite decent, useable in a pinch, but noticeably softer in extreme corners than the better lenses. Super Takumar Version 1- too soft overall, corners poor- but I may play with it as a "character" lens for black and white.

UWA? I don't have much to choose from. A Tamron 24/2.5 and an SMC 24/3.5 for primes. The SMC just doesn't cut it, while the Tamron is marginal. Both are not that sharp overall, and poor to mediocre in corners. I do have a Sigma 15-30 that is surprisingly not bad, and will be evaluating it further. I rarely use wider than 28mm so it has not been a priority.

Personally, I have no idea whether a FF sensor assembly optimized for the registration distance of K mount would produce better results than the A7r with legacy Pentax wide angle lenses. I wouldn't completely rule out the possibility.

FYI, if I didn't already have the Leica lenses I would probably have held off until Photokina to see whether Pentax coughs up a FF. I may still get one if it happens. In the absence of FF, I would probably have gone for a K3 and a Sigma 18-35, as I consider 24 MP APS-C with no AA filter to be a perfectly reasonable approach to large prints.

I find the A7r an excellent platform for the sort of thing I'm doing- MF on a tripod- but I think the K3 is a much more suitable piece of gear for most enthusiasts.

Hope some of you find this useful.

09-04-2014, 02:43 AM   #92
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QuoteOriginally posted by ElJamoquio Quote
It takes a rare lens comparison for the edges to be worse on FF than on APS-C at equivalent focal lengths. This is just another myth that won't die.
Just looking at Photozone, Canon's wide angles don't do very well in border performance compared to lenses like the Sigma 8-16 or the Tokina 11-16. It probably depends on the lens and the lens design, but I think you pay for border sharpness on full frame -- Nikon 14-24 f2.8 quality doesn't come cheap.
09-04-2014, 03:03 AM   #93
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I have been using the FA20-35 on film and its a brilliant UWA, other options could be the Sigma 15-30 as posted, also the Tamron 17-35 is supposed to be good as well.
Other advantage of something like the FA20-35 is its significantly lighter than most APS-C and FF wide angles, like my DA14mm or the Sigma/Tamron above.

I know someone local with a A7s and a Pentax adapter, might have to have a play!

The FA20-35 @ 20mm on film:


09-04-2014, 01:26 PM   #94
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QuoteOriginally posted by Rondec Quote
Just looking at Photozone, Canon's wide angles don't do very well in border performance compared to lenses like the Sigma 8-16 or the Tokina 11-16. It probably depends on the lens and the lens design, but I think you pay for border sharpness on full frame -- Nikon 14-24 f2.8 quality doesn't come cheap.
I haven't found a single FF test on photozone that does worse than the best APS-C tests at the same field of view and depth of field. Even the maligned Sigma 12-24 does better on FF than the 8-16 does on APS-C.


Part of this is because the FF test is at a slightly higher MP, but I think it's only like 15MP and 21MP so there won't be a tremendous difference when the MP's are the same.

09-04-2014, 01:45 PM   #95
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QuoteOriginally posted by ElJamoquio Quote
I haven't found a single FF test on photozone that does worse than the best APS-C tests at the same field of view and depth of field. Even the maligned Sigma 12-24 does better on FF than the 8-16 does on APS-C.


Part of this is because the FF test is at a slightly higher MP, but I think it's only like 15MP and 21MP so there won't be a tremendous difference when the MP's are the same.
photozone hasn't tested Nikon DX on the 7100 which has been out for more than a year. Those guys are so old news....2012 was the last time they were relevant, before the D7100 came out.

We do have the tests from IR where the K-3 is rated ahead of the 6D, and not far behind the D600, like about 3 or 4%.

MP does make a difference, apparently more than sensor size, at least that's what the only direct evidence would suggest.
09-04-2014, 02:23 PM   #96
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QuoteOriginally posted by ElJamoquio Quote
I haven't found a single FF test on photozone that does worse than the best APS-C tests at the same field of view and depth of field. Even the maligned Sigma 12-24 does better on FF than the 8-16 does on APS-C.


Part of this is because the FF test is at a slightly higher MP, but I think it's only like 15MP and 21MP so there won't be a tremendous difference when the MP's are the same.
Not sure what you are comparing. If I look at border performance of the Sigma 8-16mm and compare it to the border performance of the Nikkor 17-35 f2.8, what I see is that the borders and extreme borders on the Nikkor don't get up close to center sharpness till past f8. On the other hand, the Sigma seems to have decent border performance at f5.6.

But Photozone says specifically not to compare mtf numbers from one camera to another. You can only look at center versus border sharpness and how quickly things sharpen up (if they ever do) with one lens versus another.
09-04-2014, 03:44 PM   #97
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QuoteOriginally posted by Rondec Quote
Not sure what you are comparing. If I look at border performance of the Sigma 8-16mm and compare it to the border performance of the Nikkor 17-35 f2.8, what I see is that the borders and extreme borders on the Nikkor don't get up close to center sharpness till past f8. On the other hand, the Sigma seems to have decent border performance at f5.6.

But Photozone says specifically not to compare mtf numbers from one camera to another. You can only look at center versus border sharpness and how quickly things sharpen up (if they ever do) with one lens versus another.
'Cheap' lenses.

So for instance the Sigma 8-16mm, at 8 mm, wide open is 12.8mm F/7.2 equivalent.

So:

1) 8-16mm at 8mm (12.8mm F/7.2 equivalent): Border 1989
2) 12-24mm at 12.0mm and F/7.2: Border 2018 (interpolated)
3) 12-24mm at 12.8mm and F/7.2: Border 2126 (interpolated)


And this is the closest comparison I found, with a lauded APS-C lens against a derided FF lens, and in the circumstance I found where it's the closest between the two when taking the same picture.

For instance:
1) 8-16mm at 16mm, F5.6 (25.6mm F/8.96 equivalent): Border 2059
2) 12-24mm at 24mm F/8: Border 2584


or

For instance:
1) 8-16mm at 16mm, F5.6 (25.6mm F/8.96 equivalent): Center 2501
2) 12-24mm at 24mm F/8: Center 3317


I dunno. Looked around in these two lenses meant to prove your point and I didn't find any case where a APS-C had better border performance than the FF lens when taking the same picture.

---------- Post added 09-04-14 at 03:47 PM ----------

QuoteOriginally posted by normhead Quote
photozone hasn't tested Nikon DX on the 7100 which has been out for more than a year. Those guys are so old news....2012 was the last time they were relevant, before the D7100 came out.

We do have the tests from IR where the K-3 is rated ahead of the 6D, and not far behind the D600, like about 3 or 4%.

MP does make a difference, apparently more than sensor size, at least that's what the only direct evidence would suggest.
I'm not sure why you keep bringing up imaging resource in conversations with me. I've told you several times that they eyeballed their numbers... they also appear to test with jpg.


Very dangerous.


I agree that going from 15 MP to 21 MP would benefit APS-C, but it won't help much until you get to very sharp lenses - and very sharp wide angle lenses are tough to come by.

Last edited by ElJamoquio; 09-04-2014 at 03:50 PM.
09-10-2014, 12:44 PM   #98
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QuoteOriginally posted by jsherman999 Quote
Sounds like a wendyb story to me.
The funniest thing about going through those threads is this quote:

QuoteQuote:
"Hoya is re-tooling the operations, changing our organization including the attitude and culture. We're focusing on dramatically improving our planning, time to market, and overall efficiencies.

As you know, Pentax was a very conservative, slow to change, risk averse organization. This will be a thing of the past, and was truly needed if Pentax is going to succeed long term.

Having worked at Canon, Polaroid, Adobe, all of these actions make perfect sense to me.

And, despite our having an expected loss in OP due to restructuring costs and weak demand for certain models, we were not alone in struggling with severe changes in the market and economy. In this same quarter, Canon's profit was -10%, and Nikon's was -23%.

Personally, I'm really enjoying working with the new execs that Hoya has put in place to turn us around. They're very sharp, understand the market, and are making everyone accountable for their actions.

Hope this helps give you a perspective that might not be evident from all the FUD that's being promoted on the forums.
Hmmm, sounds like what people were saying about Ricoh a few years ago when they took over.
The more things change, the more they stay the same...

09-10-2014, 01:04 PM   #99
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QuoteOriginally posted by ElJamoquio Quote
'Cheap' lenses.


I'm not sure why you keep bringing up imaging resource in conversations with me. I've told you several times that they eyeballed their numbers... they also appear to test with jpg.


Very dangerous.


I agree that going from 15 MP to 21 MP would benefit APS-C, but it won't help much until you get to very sharp lenses - and very sharp wide angle lenses are tough to come by.
I keep bring this up because you keep repeating falsehoods.

They test both jpg. and raw and report on both. I have no idea why after I've provided the links with reports on their raw tests why you keep saying this.In any case, as long as they treat all images the same and maintain consistent results, their tests tell you something. Way more than idle speculation about what "should" be.

A K-3 is 24 Mp not 21... and tests at IR done the D71000 and D7000 have shown that some weak lenses benefit more from the denser photo sensitive sites than good lenses do. You keep making this assumption, and repeat it as fact when other people who have actually tested lenses on 16 MP and 24 MP say something totally different. Bad lenses are just as likely to benefit from more MP as good ones. So far I haven't heard any speculation on what the parameters might be.

Last edited by normhead; 10-02-2014 at 12:22 PM.
09-10-2014, 04:48 PM   #100
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makes sense ^
09-22-2014, 01:01 PM   #101
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QuoteOriginally posted by normhead Quote
I keep bring this up because you keep repeating falsehoods.

They test both jpg. and raw and report on both. I have no idea why after I've provided the links with reports on their raw tests why you keep saying this.In any case, as long as they treat all images the same and maintain consistent results, their tests tell you something. Way more than idle speculation about what "should" be.

A K-3 is 24 Mp not 21... and tests at IR done the D71000 and D7000 have shown that some weak lenses benefit more from the denser photo sensitive sites than good lenses do. You keep making this assumption, and repeat it as fact when other people who have actually tested lenses on 16 MP and 24 MP say something totally different. Bad lenses are just as likely to benefit from more MP as good ones. So far I haven't hard any speculation on what the parameters might be.
They use raw, fine. I ran their images through Imatest and found different results than what they're reporting. Don't like it, fine, report their falsehoods.

You say I make assumptions when really I'm reporting test results.

21 is the correct comparison, FYI, you're assuming I'm comparing things I'm not comparing.
10-02-2014, 11:56 AM   #102
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QuoteOriginally posted by mdshooting Quote
As I am getting more and more in to photography. I find myself wanting more. As we are all aware, more means, more money!

I am an avid Pentaxian and loyal to remain with the Pentax brand, however if I remove money from the conversation (I wish I could do this!!!!) what is Pentax doing to keep me as a customer? I want a Full-Frame Camera! Yet Pentax refuses to even keep us updated on how this is evolving. Would it not be better to say that they are not currently working on a Full-Frame Camera? No of course it wouldn't, to do this would encourage those waiting around to bleed off to disparate brands and get what they have wanted for sometime. Equally if they are working on something, to keep quiet only add's to frustration within the Pentax world.

I look for new gear to do things I can't presently do and find myself being tempted by other brands who offer much more, admittedly at more cost. Despite the cost, the offering's available like better video recording, full-frame, own brand lenses that give me what leave me questioning my loyalties. I still want to stay with the Pentax brand........That said.......Unless I can see that there is more coming from Pentax (at the early stage that I am at) within the Photography world would it not make sense to jump ship now before I've bought more and more equipment?

The K-3 is a leap forwards and certainly shows that Pentax is developing what they have, but I still think we have a right to know whether things are moving in a direction that this "Pentax Full Frame" thread appears to want to go.

So I ask two questions:
1. Is a Full-Frame Camera actually in development?
2. Is Pentax developing more lenses to cater or compete with there competitions third party lenses?

If no lenses are in development for the current sensors then I would have thought this suggests that Pentax is developing a Full-Frame and shifting there lens development to cater for a new breed of Pentax DSLR.

All this has started as I have spent the day trying to find good glass in the 10-24mm (16-35mm FF) range. Third party lenses can do this but the reviews, don't exactly endear me to spend the money on something that so many have declared as "not very good".

This is a little rant from me, which I must apologies. However I'm frustrated as so many other brands give me what I want, yet the brand I like so much appears to refuse to even acknowledge that the consumer wants something they don't appear too keen to put out in the public domain. Maybe it for fear that aliens will steal it who knows. Either way all comments are welcome :-)
Similar thoughts here, but for serious wide angles at the size and mechanical quality of Pentax I need to get a Leica.
A couple signs of life and some more lenses and I would feel so much better.
10-02-2014, 12:28 PM   #103
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QuoteOriginally posted by ElJamoquio Quote
They use raw, fine. I ran their images through Imatest and found different results than what they're reporting. Don't like it, fine, report their falsehoods.

You say I make assumptions when really I'm reporting test results.
You assume that imatest is better, and discount their way of doing it. I've seen inconstancies in their eyeballing as well, but I find them better than the next best thing. By the way you haven't reported any test results. You've reported a verbal summary of your findings with no numbers.

SO, what exactly are the results of your tests using imatest, K-3 vs 6D that make you so confident the 6D is better?

Start at ƒ5.6 and 100 ISO , those are my sweet spots for producing absolutely top IQ.
10-02-2014, 12:32 PM   #104
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QuoteOriginally posted by normhead Quote
You assume that imatest is better, and discount their way of doing it. I've seen inconstancies in their eyeballing as well, but I find them better than the next best thing. By the way you haven't reported any test results. You've reported a verbal summary of your findings with no numbers.

SO, what exactly are the results of your tests using imatest, K-3 vs 6D that make you so confident the 6D is better?

Start at 5.6 and 100 ISO , those are my sweet spots for producing absolutely top IQ.
D600, not 6D. I don't remember what the numbers were, but there was a ~20% difference between the two, exactly in line with expectations (APS-C without AA versus FF with AA)
10-02-2014, 01:20 PM   #105
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QuoteOriginally posted by ElJamoquio Quote
D600, not 6D. I don't remember what the numbers were, but there was a ~20% difference between the two, exactly in line with expectations (APS-C without AA versus FF with AA)
What does a "20 percent" difference mean in real life ability to print/view an image?
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