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03-08-2018, 04:48 AM   #3106
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Gotta be getting close for a release date and a price...2018 Japan Cherry Blossom Forecast - Japan Rail Pass Blog

03-08-2018, 07:02 AM - 2 Likes   #3107
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QuoteOriginally posted by beholder3 Quote
I said they tend to refocus for normal "resolution" tests which then look much better than real results, which do suffer from field curvature.
Refocussing between shots is lying to the audience.
Unless you are doing testing a better way, I don't really see the value of your criticism. Each of the testing sites has to make decisions on how to conduct their tests. Anyone who has doen any kind of testing realizes this. What is necessary is that the test be the same for all lenses.

While I would love to see more from lens rentals, as they are the only people with enough lenses, I generally find their charts to be pretty much unreadable. Photozone has a less complete way of showing data, but focuses on keeping it easily readable and understandable at a glance.

So, unless you are saying just ignore all test sites I'm not sure what you're saying.

The trouble with place like the forum is the skewed ratings based on what available at the time. Lenses the have no business being rated highly are, because at the time of release they were the best or close to the best out there. How does will the new 50 compare to the old ones?

For example the DFA 50 macro and 100 macro are rated over 9. I expect using the same scale the new 50 should be rated at least an 11. With no objective standards in place there will be simply no way to interpret how a lens 9.63 under 2015 standards compares tp a lens rated 9.63 in 2018 standards.

At least site like Photozone have held a lot of different lenses in their hands and have made the tests they feel are important.

I'm always bit mystified when folks criticize a site like Photozone, but really don't have a viable alternative. Surely part of that criticism should be pointers to who does it better.

Unless of course this list of critiques is to imply that all the work done by testers at Photozone and other test sites is worthless.

Just what are you saying here ?

I always say, the work of the test sites is limited and their weaknesses need to be understood, but they are still better than some guy who's handled 10 Pentax lenses in his whole life telling everyone about his personal preferences.

Last edited by normhead; 03-08-2018 at 07:08 AM.
03-08-2018, 07:16 AM   #3108
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QuoteOriginally posted by kjames5 Quote
As an Imaging Ambassador for Ricoh Pentax USA, I'm currently testing the new K-1 MkII, and they also sent me the new 50mm F1.4 DFA*. Here are 2 images to take a peek at, saved at 8 X 12, 300 dpi, and Level 10 JPG. These are Unsharpened, FYI. (NOTE, they appear unnaturally dark on the PF website, and the color is off too, sorry).

Attached are the exposure data for each image, a sunrise at Bryce Canyon on March 1, and an arch in the Grand Staircase Escalante on February 28.

Both were shot with the K-1 Mk II, and I'll post more images taken with that, soon.

Kerrick James
Thans for these images. I love the clrity with sand arch, and can just amaze that starburst and lack of flare. also that burst is so clear even at f11...wow!

I for one am looking forward of some more samples.
03-08-2018, 08:12 AM - 1 Like   #3109
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QuoteOriginally posted by beholder3 Quote
I said they tend to refocus for normal "resolution" tests which then look much better than real results, which do suffer from field curvature.
Refocussing between shots is lying to the audience.
It's just as much of a lie to use an out-of-focus image to test resolution and falsely claim the edges and corners are soft when they could be extremely sharp if focused correctly.

It depends on the goals of the test. If the goal is to see how sharp the edges and corners can be, then refocusing is essential.

The more important issue is that the tester should reveal how they performed the test. And, ideally, they would measure the field curvature so that lens buyers know what they are getting.

03-08-2018, 08:40 AM - 1 Like   #3110
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QuoteOriginally posted by photoptimist Quote
It's just as much of a lie to use an out-of-focus image to test resolution and falsely claim the edges and corners are soft when they could be extremely sharp if focused correctly.

It depends on the goals of the test. If the goal is to see how sharp the edges and corners can be, then refocusing is essential.

The more important issue is that the tester should reveal how they performed the test. And, ideally, they would measure the field curvature so that lens buyers know what they are getting.
Exactly.... but still the point remains, there really are no lens testers out there I can trust... although I tend to trust Imaging Resources, because they post the photos so you ca make up your own mind. But they are far from comprehensive in the selection of lenses tested.

But you're still left with the question, who can you trust?
If you add up all the negatives from various sites be it lack of Pentax glass tested, (most sites) obscure and hard to understand testing protocols (DxO and Photozone) , lack of clearly oranganized and understandable test reports, most of us end up reading as much as we can and trying to come to an "intuitive" conclusion based in impossible to compare and different test criteria.

This is compounded by the need of camera companies to sell new product. They are always going to say the latest greatest most expensive lens will give you better results. regardless of the fact that if as I've done the last few years only 3 of my images have been needed larger than the 2650x1600 image I post on the web, and those lenses would make no difference at all to me.

The information i want to know is "why would I buy this lens." That question is rarely answered. But that's all most of us want to know.
03-08-2018, 09:16 AM - 2 Likes   #3111
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QuoteOriginally posted by normhead Quote
The information i want to know is "why would I buy this lens." That question is rarely answered. But that's all most of us want to know.
Well:
1. if you need it and you have the money, you will buy it.
2. If you don't need it but you want it and you also have the money, you will buy it.

These are the 2 answers for you that works for me when I buy gear. I bought a lens a few days ago only because I want it. I still shoot with the old lens with the same focal lenght 80% of the time, but I did want this new lens.

Last edited by Dan Rentea; 03-08-2018 at 09:45 AM.
03-08-2018, 09:27 AM   #3112
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Trust (as if there were deliberate issues as e.g. objectivity) and relevance (becauce you think the tests do not expose properly qualities of the lens) are totally different issues, although they should both be taken into account to decide whether or not this or that review will be good to you (or anyone else).
03-08-2018, 10:37 AM - 2 Likes   #3113
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QuoteOriginally posted by Dan Rentea Quote
Well:
1. if you need it and you have the money, you will buy it.
2. If you don't need it but you want it and you also have the money, you will buy it.

These are the 2 answers for you that works for me when I buy gear. I bought a lens a few days ago only because I want it. I still shoot with the old lens with the same focal lenght 80% of the time, but I did want this new lens.
Indeed! Yet I think normhead's "why would I buy this lens" question refers to the more subtle interactions of lens performance and applicability.

Field curvature, to take one example, might make a lens totally useless for museum technical photography, architecture, distant landscapes, or astrophotography. On the other hand, field curvature might make a lens even more desirable for portraiture (and some kinds of nature photography) by creating a curved zone of focus that either brings the viewer into the scene or pulls the subject forward with respect to the environment. (Now there's an idea for a really unusual lens: one with a fixed focal length and an adjustable field curvature!!!)

"Why would I buy this lens" would say how that particular lens might be especially good if used in certain ways for certain genres.

03-08-2018, 10:58 AM - 1 Like   #3114
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QuoteOriginally posted by photoptimist Quote
Indeed! Yet I think normhead's "why would I buy this lens" question refers to the more subtle interactions of lens performance and applicability.

Field curvature, to take one example, might make a lens totally useless for museum technical photography, architecture, distant landscapes, or astrophotography. On the other hand, field curvature might make a lens even more desirable for portraiture (and some kinds of nature photography) by creating a curved zone of focus that either brings the viewer into the scene or pulls the subject forward with respect to the environment. (Now there's an idea for a really unusual lens: one with a fixed focal length and an adjustable field curvature!!!)

"Why would I buy this lens" would say how that particular lens might be especially good if used in certain ways for certain genres.
At the end of the day, if you gather all these (the field curvature, portraiture, architecture, distant landscapes, or astrophotography, etc.) you end up on my first reason: the need for that specific lens. You go and rent/borrow the particular lens you are interested in and try it and see if it works for you or not. You don't need a chart to tell you if the lens is good or not for you. I give you an example. I tried FA77mm side by side with DA70mm Limited. I ended up with DA70mm because it was faster to focus, a little better in terms of chromatic abberations, etc. Even if FA77mm would have won all the test charts in the world, I would still have bought the DA70mm Limited.
03-08-2018, 11:13 AM   #3115
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QuoteOriginally posted by Dan Rentea Quote
At the end of the day, if you gather all these (the field curvature, portraiture, architecture, distant landscapes, or astrophotography, etc.) you end up on my first reason: the need for that specific lens. You go and rent/borrow the particular lens you are interested in and try it and see if it works for you or not. You don't need a chart to tell you if the lens is good or not for you. I give you an example. I tried FA77mm side by side with DA70mm Limited. I ended up with DA70mm because it was faster to focus, a little better in terms of chromatic abberations, etc. Even if FA77mm would have won all the test charts in the world, I would still have bought the DA70mm Limited.
That very true, but.....

I may have a need for a given type of lens but not know whether a given model of lens is actually an example of the desired type. And maybe the issue is that we'll have to agree to disagree about the best way to figure that out.

For me, it's much easy to spend 15 minutes reviewing a trustworthy test analysis of a lens (e.g., a simple test for coma can make or break an astro lens candidate). Why reinvent the wheel? If someone trustworthy has already put in the labor to get, test, and analyze a lens, why duplicate it?

Finally, there's the interesting potential that a well-done lens review might show me that I need a lens that I did not know I needed. A good "why would I buy this lens" analysis can sell more lenses.
03-08-2018, 11:51 AM   #3116
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QuoteOriginally posted by BigMackCam Quote
I think that's highly unlikely, Ron, given that the Tokina version - using Pentax's design - is due for release this Summer. I could be wrong, but I just don't see Ricoh waiting another nine months after that...
Well cherry blossom season is over by then.
03-08-2018, 11:58 AM   #3117
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QuoteOriginally posted by RonHendriks1966 Quote
Well cherry blossom season is over by then.
It is, but enthusiasm for the lens won't be, and Ricoh will want to get the lens out into the market as soon as possible. If Tokina is almost ready to ship its rebadged version, Ricoh should be slightly ahead of or behind that. We'll find out soon enough
03-08-2018, 01:36 PM   #3118
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QuoteOriginally posted by normhead Quote
Unless you are doing testing a better way, I don't really see the value of your criticism. Each of the testing sites has to make decisions on how to conduct their tests. Anyone who has doen any kind of testing realizes this. What is necessary is that the test be the same for all lenses.

While I would love to see more from lens rentals, as they are the only people with enough lenses, I generally find their charts to be pretty much unreadable. Photozone has a less complete way of showing data, but focuses on keeping it easily readable and understandable at a glance.

So, unless you are saying just ignore all test sites I'm not sure what you're saying.

The trouble with place like the forum is the skewed ratings based on what available at the time. Lenses the have no business being rated highly are, because at the time of release they were the best or close to the best out there. How does will the new 50 compare to the old ones?

For example the DFA 50 macro and 100 macro are rated over 9. I expect using the same scale the new 50 should be rated at least an 11. With no objective standards in place there will be simply no way to interpret how a lens 9.63 under 2015 standards compares tp a lens rated 9.63 in 2018 standards.

At least site like Photozone have held a lot of different lenses in their hands and have made the tests they feel are important.

I'm always bit mystified when folks criticize a site like Photozone, but really don't have a viable alternative. Surely part of that criticism should be pointers to who does it better.

Unless of course this list of critiques is to imply that all the work done by testers at Photozone and other test sites is worthless.

Just what are you saying here ?

I always say, the work of the test sites is limited and their weaknesses need to be understood, but they are still better than some guy who's handled 10 Pentax lenses in his whole life telling everyone about his personal preferences.
I agree with you and like ephotozine. They do not seem biased towards a brand name either; which is apparent with their review of the Canon 50mm 1.2L USM. It will be their test that is the determining factor if this will be my next lens or not. I would much prefer Pentax to have went with a 24mm lens; but I can make a 50mm work provided it is top notch from the center to the edge.

Landscapes,night photography, and astrophotgraphy. My next prime lens will be tack sharp; that is a requirement.

Last edited by JamesDCrockett; 03-08-2018 at 02:34 PM.
03-08-2018, 01:48 PM   #3119
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the only lens reviews i trust are full size images on flickr.
03-08-2018, 01:55 PM   #3120
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QuoteOriginally posted by sculptor666 Quote
the only lens reviews i trust are full size images on flickr.
I trust ephotozine but buy knowing the return policies of both B&H Photo and Adorama. I may order this one through Dodds since I can drive there in less than 30 minutes if I decide to return it. But then again, I do like the price of Adorama's 2 year drops and spills warranty; so maybe I won't go through Dodds.

Last edited by JamesDCrockett; 03-09-2018 at 08:57 AM.
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