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02-05-2015, 12:39 AM   #181
ogl
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02-05-2015, 12:41 AM   #182
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RiceHigh will be frothing at the mouth over this...

---------- Post added 02-05-15 at 06:12 PM ----------

Interesting MTF charts there OGL.
For reference, the MTF charts from the Sigma 100-300mm f/4 APO EX DG:



MTF from the Sigma 120-300mm f/2.8 APO "Sport" OS:



And the Sigma 70-200mm f/2.8 APO EX DG OS:



If those charts OGL posted are accurate, the Pentax D-FA*70-200mm f/2.8 will outperform the Sigma 70-200mm. The 150-450mm f/4.5-5.6 will face stiff competition from sigma, Nikon and Canon offerings, but it looks promising.

Last edited by Digitalis; 02-05-2015 at 01:00 AM.
02-05-2015, 12:45 AM   #183
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Could someone please enlighten me as to what the MTF charts are telling us? Do they look good, or not?
02-05-2015, 12:47 AM   #184
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I had been eyeing the Sigma 150-500 for a while as the longest lens I've got is the 55-300, but since the 150-450 was put on the roadmap I've been patient... really looking forward to getting my hands on it one day!

02-05-2015, 12:47 AM   #185
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QuoteOriginally posted by Clavius Quote
Are we sure it's not some bad photoshop of a K-5 and a 67? That prism looks exactly like the one on the 67. Apart from that... It looks huge!
To me that picture looks like it's of an actual part, made with 3D printing technique. There are horizontal layers going through the print which to me seem similar than the ones our 3D printer leaves to the parts. The PENTAX text and lens are probably added after the picture is taken.
02-05-2015, 12:54 AM   #186
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QuoteOriginally posted by Cynog Ap Brychan Quote
Could someone please enlighten me as to what the MTF charts are telling us? Do they look good, or not?
Please correct me if I'm wrong, I just looked it up.

The left side of the chart is the center, going right further from the center. The side numbers are percentage of contrast, the higher the better, the different lines are lower and higher frequency lines on the chart.

The higher the better, the flatter the better.

It looks like the long zoom improves as it stops down at full extension. How that will translate into actual use I don't know. But it seems to be optimized for use long.

Comparing to the Sigmas, the 300mm zooms are known to be very sharp, it would seem to be pretty good. Again, we shall see in actual use.

I'm suspecting that my fears are being confirmed; this lens will be very sharp and will take away any reasons for me not to buy it. I still maintain hope that it sucks and removes that possibility.
02-05-2015, 12:56 AM   #187
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QuoteOriginally posted by ASa Quote
To me that picture looks like it's of an actual part, made with 3D printing technique. There are horizontal layers going through the print which to me seem similar than the ones our 3D printer leaves to the parts. The PENTAX text and lens are probably added after the picture is taken.
It is a 3D printed prototype and the text is just a sticker.
02-05-2015, 01:02 AM   #188
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To compare with the latest iteration of a similar Canon lens.

Canon U.S.A. : Consumer & Home Office : EF 100-400mm f/4.5-5.6L IS II USM

---------- Post added 02-05-15 at 12:04 AM ----------

Just got an email from B&H with the new lenses.

Just Announced from Olympus, Pentax, & Sekonic

02-05-2015, 01:05 AM   #189
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QuoteOriginally posted by ZoeB Quote
I thought you could take a joke but you've certainly been teasing us for a long time!
Hehe, i do and i will much more in the time to come
02-05-2015, 01:19 AM   #190
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That 150-450 is the lens I've been waiting for. Steep price, but that confirms it will be a top notch lens, as do all the features if offers. I'm starting a dedicated savings account for it now I think.

The FF will only be for me if Pentax would decide to dumb down the APS-C line and not provide a decent successor to the K-3. Though for now my K-3 still has considerable mileage left in it. Also, it would be a shame to have waited so long for a decent long wildlife zoom on APS-C (that's what the 150-450 is for me) and heavily invest in it, only to have its long end FOV reduced (by moving to a FF camera) to the slightly too short range I had on APS-C all along with my 300mm...

A very happy and soon to be poor,
Wim
02-05-2015, 01:21 AM   #191
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That 3D printed FF prototype is very unusual for Pentax. What gives? All prototypes up to now have been made from the real material. This can mean two things:

1. The design is far from ready as if they started just yesterday;
2. They want to keep the competition in the dark as much as possible, without showing too little to the Pentax customers.

When the 645D was in the prototype stage it always looked like a finished product. Pentax could get away with that because in that field (middle format DSLR) there is almost no competition, especially not from Canon and Nikon. In the case of the FF however, secrecy is key. The 3D product as it is now probably won't trigger Canon and Nikon enough to take notice of Pentax. And who knows, the camera might show up sooner rather than later. It's all part of the plan to deceive Canikon and keep existing (and old) customers happy.
02-05-2015, 01:23 AM   #192
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You raise some interesting points there, Asahiflex.

The 645D mock-ups always did have a highly polished look to them, it is indeed curious that the anticipated full frame DSLR doesn't show the same degree of development.

Last edited by Digitalis; 02-05-2015 at 01:33 AM.
02-05-2015, 01:29 AM   #193
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QuoteOriginally posted by Tesla Quote
It is a 3D printed prototype and the text is just a sticker.
Exactly, i'ts a very simple model, kind of make one wonder if it's really legit.
02-05-2015, 01:34 AM   #194
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QuoteOriginally posted by derekkite Quote
Please correct me if I'm wrong, I just looked it up.

The left side of the chart is the center, going right further from the center. The side numbers are percentage of contrast, the higher the better, the different lines are lower and higher frequency lines on the chart.

The higher the better, the flatter the better.

It looks like the long zoom improves as it stops down at full extension. How that will translate into actual use I don't know. But it seems to be optimized for use long.

Comparing to the Sigmas, the 300mm zooms are known to be very sharp, it would seem to be pretty good. Again, we shall see in actual use.

I'm suspecting that my fears are being confirmed; this lens will be very sharp and will take away any reasons for me not to buy it. I still maintain hope that it sucks and removes that possibility.
Also just doing some learning on the fly, my understanding is similar:
I think the left of the horizontal axis is the centre of the image the 70-200 has awesome contrast (S:10 & M:10) across the frame, resolution is good in the center and drops off toward the edge (S:30 & M:30).

The following notation comes from the test charts they use
S = Sagital lines (these are lines going in the direction from the center to the corner of the frame)
M = Meridonial Lines (the are lines running perpendicular to sagital lines)
10 = 10 lines per mm (used for measuring contrast)
30 = 30 lines per mm (used for measuring resolution)
02-05-2015, 01:38 AM   #195
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You guys are correct on the MTF charts - here is an excerpt on the Luminous landscapes excellent article on Understanding MTF:

QuoteQuote:
Here are some rules of thumb for reading a chart...
the higher up the chart the 10 LP/mm line is (the thick lines), the higher the contrast reproduction capability of the lens will be.
the higher up the chart the 30 LP/mm line is (the thin lines*), the higher the resolving power and thus subjective sharpness of the lens will be.
generally speaking a lens whose thick lines (10 LP/mm) are above .8 on the chart should be regarded as having excellent image quality. Above .6 is regarded as "satisfactory". Below .6 is, well, below.
* or in our case, the dashed lines.
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