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04-28-2016, 03:18 AM   #61
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I fully agree. The system needs to continue being markedly cheaper than P1/H while delivering results that are at least as good as all but their top products, while offering improvements over FF. That's a balance they have achieved thus far and I hope they keep doing so.

If there is a price/volume point that could somehow deliver a 21mm f2.4 for around $5k, I believe they would be onto a winner. The difference between that and 7-8k would make it popular and also keep the system clearly ahead of FF for a range of applications like low light work... Similarly a fast portrait lens would do the same for that market.

Can that be pulled off commercially and technically? No idea. But I hope so!

04-28-2016, 03:37 AM   #62
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QuoteOriginally posted by itshimitis Quote
Are you suggesting there is no difference between an image from the K1 and 645Z? If so, prove it.
I said hardly any, which means almost no difference. The difference is level of details on moving subjects. And maybe handling and lens specific behaviour, but thats a preference question. Thats it.

Where the difference in favour of 645Z lacks:

- Level of detail on stationary objects. K-1 pixel shift resolution with 36,4M full RGB pixels matches the detail level of 645Z 51 Mp bayer pattern quite well.

- Image noise on both stationary and moving objects. Using f/2,2 on K-1 gives you the same image noise with the same DoF and shutter speed as using a f/2,8 lens on 645Z. Assuming the sensors have the same per area quality. Thats probably a fair assumption as the K-1 sensor and 645Z is both from Sony and the same generation of the same technology. If you are ok with larger apertures and shorter DoF compared to the 645Z option you can even get less image noise at the same shutter speed. K-1 got a 1,3 stop noise advantage when comparing f/2,8 lenses against f/1,4 lenses. If you mention the 67 105mm f/2,4 with an adapter, I will mention the A50 f/1,2 and the 1,3 stops difference persists.

- Depth of field (for the short DoF-people) on both still and moving objects. You can get the same DoF using a 0,7 stop faster lens on K-1, or you can get shorter DoF on K-1 using larger apertures. The 645Z offers no larger apertures then f/2,8 so thats really an easy match for K-1 with its large range of faster then f/2,2 primes. Its the same story for zooms only shifted a bit up in aperture numbers.

I call these key areas where the current 645 system don’t have an advantage. The 645 actually have a 1,3 stop large disadvantage in two of these areas.

---------- Post added 04-28-16 at 12:45 PM ----------

QuoteOriginally posted by Ed Hurst Quote
If there is a price/volume point that could somehow deliver a 21mm f2.4 for around $5k, I believe they would be onto a winner. The difference between that and 7-8k would make it popular and also keep the system clearly ahead of FF for a range of applications like low light work... Similarly a fast portrait lens would do the same for that market.
I think the 21mm f/2,4 will be technically impossible with the current focal flange distance, and I don't think the market for this lens would be nearly as big as the wedding portrait market. I think a f/2,0 portrait prime is both technically and economically achievable with FF 645. Think 6x7 105mm f/2,4 + a slight speed booster (reducer) to get an idea of size. The price might surprise you as these probably would be quite cheap to produce.

Last edited by Simen1; 04-28-2016 at 04:01 AM.
04-28-2016, 04:32 PM   #63
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QuoteOriginally posted by Simen1 Quote
Level of detail on stationary objects. K-1 pixel shift resolution with 36,4M full RGB pixels matches the detail level of 645Z 51 Mp bayer pattern quite well.
You obviously have a K1 already and have tested side by side with a 645z I guess to be able to say this?

QuoteOriginally posted by Simen1 Quote
Depth of field (for the short DoF-people) on both still and moving objects. You can get the same DoF using a 0,7 stop faster lens on K-1, or you can get shorter DoF on K-1 using larger apertures. The 645Z offers no larger apertures then f/2,8 so thats really an easy match for K-1 with its large range of faster then f/2,2 primes. Its the same story for zooms only shifted a bit up in aperture numbers.
You are missing here,

a) How the bokeh is rendered

b) the increased compression by inherently using longer focal lengths on the 645z which is typically a desired attribute of a portrait shooter. I'm sure the k1 (as most 35's do) a fine job - but by saying "well dof is the same because i can use wider apertures" is not stricty true and is a very selective comparison.

QuoteOriginally posted by Simen1 Quote
I think a f/2,0 portrait prime is both technically and economically achievable with FF 645. Think 6x7 105mm f/2,4 + a slight speed booster (reducer) to get an idea of size. The price might surprise you as these probably would be quite cheap to produce.
I'm not sure about the price but definitely technically possible, as I use f/2 lenses on my 645z already and they work beautifully - just with a adapter.
04-28-2016, 11:28 PM   #64
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QuoteOriginally posted by gavincato Quote
You obviously have a K1 already and have tested side by side with a 645z I guess to be able to say this?

a) How the bokeh is rendered

b) the increased compression by inherently using longer focal lengths on the 645z which is typically a desired attribute of a portrait shooter. I'm sure the k1 (as most 35's do) a fine job - but by saying "well dof is the same because i can use wider apertures" is not stricty true and is a very selective comparison.
Gavin, a while back a few people on the forum here shot me down when I said that the image difference inherent with using medium format over 35mm, or 35mm over aps-c, is because of the fact that you are using a longer focal length to create the same field of view, which not only changes the perspective of the image, compression and also the level of detail captured because of the longer focal length. I was left feeling sorry and alone at this point. Are you saying that I was correct?

04-29-2016, 02:07 AM   #65
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QuoteOriginally posted by gavincato Quote
You obviously have a K1 already and have tested side by side with a 645z I guess to be able to say this?
I get your point. Math and physics are not enough. You want to see the effect in real life to believe in it. I don’t think this is a physical and mathematical field that is uncertain and have to be approved by measurements to get its acknowledge.

QuoteOriginally posted by gavincato Quote
You are missing here,

a) How the bokeh is rendered

b) the increased compression by inherently using longer focal lengths on the 645z
I didn’t miss a). I wrote "And maybe handling and lens specific behaviour, but thats a preference question."
I didn’t miss b) ether, since its a false claim. Compression and perspective are the same phenomenon written in two different ways. If you keep field of view constant, you get the same compression too. For instance using the FA43mm with K-1 and the D-FA 645 55mm with 645Z.

QuoteOriginally posted by gavincato Quote
as I use f/2 lenses on my 645z already and they work beautifully - just with a adapter.
I read about the Contax lens in one of your earlier posts. The shots you showed looks like the bokeh is rendered very nicely.
04-29-2016, 02:55 PM   #66
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QuoteOriginally posted by Simen1 Quote
Compression and perspective are the same phenomenon written in two different ways. If you keep field of view constant, you get the same compression too. For instance using the FA43mm with K-1 and the D-FA 645 55mm with 645Z.
from a portrait point of view that is not true. there are marked and easily noticeable differences to using longer lenses. i have sample pics here from my canon & 645z that demonstrate this but I'm heading off to shoot a couple of weddings.
05-17-2016, 11:59 AM   #67
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Does anyone involved with this thread have a 645z or 645d with 67 105/2.4, and images to post???
I would think, given the cost, this would be worth trying moreso than this much discussion about a non-existent lens. (Though I agree - it'd be fantastic if it did in fact exist). I know Mike Oria has (had?) one though it seems portraiture and candid shots would be the most useful.

Last edited by chickentender; 05-17-2016 at 03:23 PM. Reason: typo
05-17-2016, 02:47 PM   #68
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QuoteOriginally posted by chickentender Quote
Does anyone involved with this thread have a 645z or 645d with 67 80/2.4, and images to post???
I would think, given the cost, this would be worth trying moreso than this much discussion about a non-existent lens. (Though I agree - it'd be fantastic if it did in fact exist). I know Mike Oria has (had?) one though it seems portraiture and candid shots would be the most useful.
I have the 6x7 105mm f2.4 (no such thing as an 80mm f2.4), and used it with my 645D and 645Z. It does well, though more characterfully than technically (judged by high, modern standards).

However, being 105mm, it does nothing whatever to meet the need for a fast wide angle, so the idea of enjoying what exists rather than wanting something that (so far) does not doesn't really apply; they can't be considered comparable. It's a bit like saying "I know you want a rose, but use this sausage instead since you happen to possess one." As George Orwell put it, "...their uses hardly intersect."

05-17-2016, 03:39 PM   #69
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QuoteOriginally posted by Ed Hurst Quote
I have the 6x7 105mm f2.4 (no such thing as an 80mm f2.4), and used it with my 645D and 645Z. It does well, though more characterfully than technically (judged by high, modern standards).
Oops. (I've corrected it.) Yes, I realize that. I meant 105mm - guess I read 80mm so many times here I typed it.

QuoteQuote:
However, being 105mm, it does nothing whatever to meet the need for a fast wide angle, so the idea of enjoying what exists rather than wanting something that (so far) does not doesn't really apply; they can't be considered comparable. It's a bit like saying "I know you want a rose, but use this sausage instead since you happen to possess one." As George Orwell put it, "...their uses hardly intersect."
Ok, interesting. I suppose that's fair to some extent while at the same time the 105/2.4 and 90/2.8 (67) are indeed spoken of in the same sentence more often than not and are used for the same purpose. Is the additional 10mm the cut-off in your view? Absolutley *not* to diminish anyone's wants and desires, but I'd hazard a guess that the one of these (particularly the former) could meet some of those wants in specific instances. That's a nice quote, but can you really say the Zeiss 80/2 is the rose to the P 105/2.4 sausage? There is more than just *some* intersection after all.

At any rate - I only meant to suggest folks try that one because it is relatively inexpensive and likely easily overlooked from 645 perspective.
And after all, we're talking about the equivalent difference of roughly 50 to 70mm in 135 terms. Not "wide angle" to be sure.

Last edited by chickentender; 05-17-2016 at 03:47 PM.
05-17-2016, 03:49 PM   #70
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QuoteOriginally posted by trusharp Quote
Somebody prove me wrong on this.

I've been thinking a lot recently and have come to the succinct conclusion that Ricoh really needs to bestow a f2.0 or faster lens upon its loyal followers preferably around the 50mm (35mm) length.

Now this may not financially be a good idea at first but lets think about this properly.

Almost all wedding film photographers pretty much use one system, the Contax. Furthermore almost all of them swear by the 80mm f2 for 95% of their work.

Its no secret that film is getting to the point that it will either be too expensive to use for wedding photographers or go out of production entirely.

Ofcourse its true that 35mm dslr's with their fast 1.4 lenses are great but looking at the capabilities of the 645z vs almost all DSLR bodies, there is no comparison, in my experience anyway.

Long story short, I'd buy one. I wish there was one to buy now and unless its unfeasible, I'd be over the moon if there was even a fart of a rumour

Am I wrong here?
Mamiya 645 system 80/1.9 is the fastest MF glass.
05-17-2016, 04:18 PM   #71
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QuoteOriginally posted by Simen1 Quote
I said hardly any, which means almost no difference. The difference is level of details on moving subjects. And maybe handling and lens specific behaviour, but thats a preference question. Thats it.

Where the difference in favour of 645Z lacks:

- Level of detail on stationary objects. K-1 pixel shift resolution with 36,4M full RGB pixels matches the detail level of 645Z 51 Mp bayer pattern quite well.

- Image noise on both stationary and moving objects. Using f/2,2 on K-1 gives you the same image noise with the same DoF and shutter speed as using a f/2,8 lens on 645Z. Assuming the sensors have the same per area quality. Thats probably a fair assumption as the K-1 sensor and 645Z is both from Sony and the same generation of the same technology. If you are ok with larger apertures and shorter DoF compared to the 645Z option you can even get less image noise at the same shutter speed. K-1 got a 1,3 stop noise advantage when comparing f/2,8 lenses against f/1,4 lenses. If you mention the 67 105mm f/2,4 with an adapter, I will mention the A50 f/1,2 and the 1,3 stops difference persists.

- Depth of field (for the short DoF-people) on both still and moving objects. You can get the same DoF using a 0,7 stop faster lens on K-1, or you can get shorter DoF on K-1 using larger apertures. The 645Z offers no larger apertures then f/2,8 so thats really an easy match for K-1 with its large range of faster then f/2,2 primes. Its the same story for zooms only shifted a bit up in aperture numbers.

I call these key areas where the current 645 system don’t have an advantage. The 645 actually have a 1,3 stop large disadvantage in two of these areas.

---------- Post added 04-28-16 at 12:45 PM ----------


I think the 21mm f/2,4 will be technically impossible with the current focal flange distance, and I don't think the market for this lens would be nearly as big as the wedding portrait market. I think a f/2,0 portrait prime is both technically and economically achievable with FF 645. Think 6x7 105mm f/2,4 + a slight speed booster (reducer) to get an idea of size. The price might surprise you as these probably would be quite cheap to produce.
Well I am in Paris right now and shooting with the K1 and 645z. I can tell you that there is a clear difference in the files. The K1 files don't in my view hold a candle to the 645 files, the detail is there, but its not as good. I got the k1 purely because the Z is not a walk around camera.
05-17-2016, 06:15 PM   #72
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QuoteOriginally posted by chickentender Quote
Oops. (I've corrected it.) Yes, I realize that. I meant 105mm - guess I read 80mm so many times here I typed it.



Ok, interesting. I suppose that's fair to some extent while at the same time the 105/2.4 and 90/2.8 (67) are indeed spoken of in the same sentence more often than not and are used for the same purpose. Is the additional 10mm the cut-off in your view? Absolutley *not* to diminish anyone's wants and desires, but I'd hazard a guess that the one of these (particularly the former) could meet some of those wants in specific instances. That's a nice quote, but can you really say the Zeiss 80/2 is the rose to the P 105/2.4 sausage? There is more than just *some* intersection after all.

At any rate - I only meant to suggest folks try that one because it is relatively inexpensive and likely easily overlooked from 645 perspective.
And after all, we're talking about the equivalent difference of roughly 50 to 70mm in 135 terms. Not "wide angle" to be sure.
The sausage / rose comparison was not about 105 vs 90 or 80, but the discussion above about fast wide angles, which are quite different subjects :-)
05-17-2016, 07:47 PM   #73
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QuoteOriginally posted by 2351HD Quote
Well I am in Paris right now and shooting with the K1 and 645z. I can tell you that there is a clear difference in the files. The K1 files don't in my view hold a candle to the 645 files, the detail is there, but its not as good. I got the k1 purely because the Z is not a walk around camera.
I would love to know more. Have been considering selling my A7R and popping into a K1 as my Z backup. Although What I really need is something like the RX1RII, or better the camera that doesn't exist, yet so many of us want: something like the old Fuji 645's in digital.
05-17-2016, 07:57 PM   #74
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Tex the files are great from the K1, if you are coming from any other camera other than a recent gen MF CMOS sensor. I personally feel that it's the combination of the pixel size and the fact that you are using longer focal lengths to achieve the same image on the 645 as you do the K1.

The detail is just more "apparent" in the 645 files at 100%.

Also when you nail focus on the 645z and review on screen, you know you've got it, but on the K1, it's harder to see, much harder. I've taken multiple shots just to get it right and when I've gotten it back to the laptop, the first was ok but the screen just couldn't assure me of that.

I am loving the K1 in the field though, so lovely to use and the mirror assembly is great. It was either this or an A7rIi and I finally chose the K1 for the look and feel of the body, controls and the file quality is ahead of the A7rII in my view.

I will be reserving my final K1/645 comparison until I return home, because my laptop monitor is a much higher res than my calibrated screens at home and I need to compare on common ground so I have a reference point.
05-17-2016, 08:07 PM   #75
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QuoteOriginally posted by 2351HD Quote
Tex the files are great from the K1, if you are coming from any other camera other than a recent gen MF CMOS sensor. I personally feel that it's the combination of the pixel size and the fact that you are using longer focal lengths to achieve the same image on the 645 as you do the K1.

The detail is just more "apparent" in the 645 files at 100%.

Also when you nail focus on the 645z and review on screen, you know you've got it, but on the K1, it's harder to see, much harder. I've taken multiple shots just to get it right and when I've gotten it back to the laptop, the first was ok but the screen just couldn't assure me of that.

I am loving the K1 in the field though, so lovely to use and the mirror assembly is great. It was either this or an A7rIi and I finally chose the K1 for the look and feel of the body, controls and the file quality is ahead of the A7rII in my view.

I will be reserving my final K1/645 comparison until I return home, because my laptop monitor is a much higher res than my calibrated screens at home and I need to compare on common ground so I have a reference point.
Thank you, and I look forward to seeing further reports. I will say that I had a brief opportunity to handle one at B&H a few a couple of weeks ago, and it seemed an interesting combo of solid yet light, compact yet chunky. Weird. I thought the controls were interesting, but not entirely sure about the haptics for me after using the Z. The viewfinder was an adjustment as well after the wonderful Z experience. I rather like and prefer the EVF of the R, it affords some interesting advantages in low light, plus magnification.

Honestly, I thought the K1 was cool but not for me, until I saw the specs. Then I got a bit more interested. And then my interest jumped when the price was announced.

Anyway, I await more from you
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