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09-09-2011, 02:51 AM   #76
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QuoteOriginally posted by falconeye Quote
And only about 1.8x vs. a 24MP K-5mkII or NEX7, i.e., not more than what a 1.7x TC provides.
That's assuming the TC doesn't degrade resolution, isn't it? (I.e. not quite so IRL?)

09-09-2011, 04:07 AM   #77
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QuoteOriginally posted by smc Quote
so if I understand your previous post, for longer lenses, we are limited to glass that is sharp wide open at F5.6?
Sharpest at f/4 would be better. But you're not limited. You just don't get the full 12MP resolution. At f/8, you still get some 3 MP (after sharpening) which mean the toy lenses (some are f/8 fixed) may still be good enough for HD video.
09-09-2011, 04:09 AM   #78
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QuoteOriginally posted by gazonk Quote
That's assuming the TC doesn't degrade resolution, isn't it? (I.e. not quite so IRL?)
Yes. But even using a K-5, I've seen detail with the Pentax 1.7x TC I couldn't see without. When using good lenses.

But you're right, the Q is the better TC, about 1.8x (24MP) to 2.2x (16MP). Unfortunately, w/o AF.
09-09-2011, 09:46 AM   #79
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QuoteOriginally posted by falconeye Quote
What has been said here about the diffraction limits is not accurate.

I tried to make a more accurate statements here:

Basically, the Q is "influenced" by diffraction between f/2 and f/4 (loosing contrast in a recoverable way using sharpening tools as MTF doesn't become zero at Nyquist) and then looses resolution when going beyond (e.g., at f/8, 100% crops look visibly soft).

Therefore, shooting a DA*300 or DA*60-250 with a Q at their sharpest aperture (about f/5.0) will still deliver plenty of detail a K-5 won't render.

But the additional reach will not be that of the crop factor. It will be only roughly be 2-2.5 vs. a K-5 (because you can crop a K-5 image more). And only about 1.8x vs. a 24MP K-5mkII or NEX7, i.e., not more than what a 1.7x TC provides. OTOH, the * lenses do resolve enough detail to exploit this ~2x factor near the center.
Hi Falk,

Thanks for doing the math! Your calculations pretty much confirm what I felt intuitively -- that my premium teles would work pretty well with the Q + adapter. The thing that I didn't factor into my considerations was the comparison with K-5 crops, so the actual advantage will not be as great as I had anticipated .

Luckily, I have some really good teles to play with -- D FA 100/2.8 Macro, Tamron SP 180/2.5, Sigma EX 180/3.5 Macro, A* 200/2.8, FA* 300/4.5, FA* 300/2.8, Sigma EX 300/2.8 APO, so it should still be fun as these all resolve pretty well wider than f5.6. . . now I need to find some tripod rings for some of these lenses. . .and a very good light tripod -- it never ends. . .

The IQ also holds up pretty well with most of these lenses with the Sigma EX 1.4x APO TC or the F 1.7x AFA, so these will also be worth a try with the faster lenses, IMO.

Scott

09-09-2011, 10:39 AM   #80
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QuoteOriginally posted by snostorm Quote
D FA 100/2.8 Macro
Tamron SP 180/2.5
Sigma EX 180/3.5 Macro
A* 200/2.8
FA* 300/4.5
FA* 300/2.8
Sigma EX 300/2.8 APO
Scott, the Q provides an excellent opportunity to find out what these fine lenses are really capable of. Measurements like photozone.de cannot go beyond the 4.8/6m of sensors used.

Of course, the 300mm are the most interesting ones. Nevertheless, my own measurements tell me that the DA*60-250 at 250mm may resolve equally well in the center.
09-09-2011, 11:10 AM   #81
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QuoteOriginally posted by falconeye Quote
Of course, the 300mm are the most interesting ones. Nevertheless, my own measurements tell me that the DA*60-250 at 250mm may resolve equally well in the center.
What about the 200mm f2.8? That should be a great match optically.
And the D FA 100mm is so compact, it won't look out of place at all.
09-09-2011, 11:23 AM   #82
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QuoteOriginally posted by audiobomber Quote
What about the 200mm f2.8? That should be a great match optically.
And the D FA 100mm is so compact, it won't look out of place at all.
I would always prefer a DA*300 on a K-5 over the DFA100 on a Q ...
09-09-2011, 11:27 AM   #83
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QuoteOriginally posted by falconeye Quote
I would always prefer a DA*300 on a K-5 over the DFA100 on a Q ...
Oh sure, except of course for size.

09-09-2011, 11:50 AM   #84
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QuoteOriginally posted by audiobomber Quote
Oh sure, except of course for size.
Ok, if you prefer to keep it small ...
I'd have a serious look at the DA 70 Ltd. It seems to have the biggest resolution muscle of all longer DAs.

On the Q, use it at f/3.2 and enjoy a true 400mm lens FoV (35mm equivalent).
09-09-2011, 12:05 PM   #85
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QuoteOriginally posted by audiobomber Quote
What about the 200mm f2.8? That should be a great match optically.
And the D FA 100mm is so compact, it won't look out of place at all.
Hi Dan,

The possibility of using the smaller teles are one of the reasons why I initially got pumped for the Q. If I can get similar results with the little body and the D FA 100 Macro as I get with a DSLR and a 300/2.8, then the size and weight advantages will be well worth the Q's cost for me. This is the one thing that those who are comparing the size of the Q to the 4/3 and APS-C MILCs don't seem to get. With either of the latter bodies, they'd still have to carry the 300/2.8 to get equivalent reach (FOV) and lens speed. . .not to mention the tripod needed to support it all, and this just can't come close to comparing to the convenience of a 20 oz alternative, despite some loss of ultimate IQ potential.

All of the Pentax 200/2.8s are exemplary lenses if my A*200/2.8 is any indication, and most reviewers of the FA* and DA* versions seem to confirm that if anything, the optics have just gotten better (though not really that much -- it's hard to improve much on "superb" ). Since they'd all be fully manual with the Q, the A* is looking like it's going to be a great match with the Q though it's a bit heavier than the AF versions . It's currently a bit of an orphaned child with my DSLRs since the FL is not quite long enough for my use, so it will be very happy to get the call more often. . .I can also see using the Tamron SP 80-200/2.8 Adaptall 2, even though it's something of a beast in comparison, but it's a great lens.

Scott
09-09-2011, 06:49 PM   #86
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Can't wait to try the Q with some of my longer lenses. For Pentax: 77 ltd, DFA 100 and A*200 for macro, and DA*300 for wildlife. From Oympus: 55 1.2, 100 2, 180 2, and 350 2.8. Also have the matched 1.4 teleconverter. The Q is going to be a fun camera!
thanks
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Would still love to see a field compressor.
09-12-2011, 05:35 AM   #87
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Rayqual announced new adapters with built-in tripod mount

They also show new adapters for the Q.
http://www.rayqual.com/

09-12-2011, 06:07 AM   #88
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QuoteOriginally posted by jogiba Quote
They also show new adapters for the Q.
http://www.rayqual.com/
All manual focus only.

Now, Olympus, Panasonic, Sony and Nikon mirrorless all support AF with their adapters:
So, it will become increasingly tough for Pentax to market a mirrorless system with no AF adapters available.
09-12-2011, 06:57 AM   #89
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QuoteOriginally posted by falconeye Quote
All manual focus only.
...
So, it will become increasingly tough for Pentax to market a mirrorless system with no AF adapters available.
I'm not so sure. The NEX LA-EA2 AF adapter is large and clunky and costs a few hundred. Things get even more ungainly when you add a normal sized A-mount lens onto the Sony adapter.


[image from ephotozine's review of the NEX5N

The penalty of extra bulk and $ probably means these sort of add-ons aren't a must-have feature for compact mirrorless. I wouldn't be surprised if hardly anyone buys these things.
09-12-2011, 07:18 AM   #90
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