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08-04-2020, 08:35 PM   #46
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QuoteOriginally posted by boojum Quote
It may be that Metabones is waiting to reach a certain number of pre-orders. When they reach a good profit point they will start banging them out. If they do not get enough orders they may just shine the whole thing on. After all, how great a difference can there be in the manufacture of ones for Nikons and ones for the K > Q design?

I hope you guys get your Metabones. From the three photos posted, all muddy, I think I will pass. Let me ask, does Metabones degrade the color a bit or are those just three bad photos?
I quickly took one into Photoshop and it processed quite nicely. A surprising amount of detail, sharp in the center, with just a little chromatic aberration along the edges. Very usable.

08-04-2020, 09:53 PM   #47
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QuoteOriginally posted by johnmflores Quote
I quickly took one into Photoshop and it processed quite nicely. A surprising amount of detail, sharp in the center, with just a little chromatic aberration along the edges. Very usable.
I agree. Plenty of detail to work with. CA not bad at all.
As good as the 50 1.2 is, it is a vintage lens that's not designed for corner to corner sharpness on high pixel density modern cameras.

I'd say it is a good performance by the speedbooster.

Now let's get some modern glass on there and see what we an do.
How about the the DA*300. It becomes a 150mm f/2 with a 700mm equiv FOV.
Or the DA 35mm Ltd. It becomes an 18mm f/1.4 with a 80mm equiv FOV.
Or the compact 21/40/70 pancakes...
08-05-2020, 07:49 AM   #48
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QuoteOriginally posted by caliscouser Quote
Now let's get some modern glass on there and see what we an do.
How about the the DA*300. It becomes a 150mm f/2 with a 700mm equiv FOV.
Or the DA 35mm Ltd. It becomes an 18mm f/1.4 with a 80mm equiv FOV.
For the "equivalent" focal lengths,
I think you may be dividing, when you should be multiplying.

So the DA 35 Ltd should roughly translate to an FF 85/1.4.
But the bokeh might be strange at portrait distances or longer.
08-05-2020, 01:24 PM   #49
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QuoteOriginally posted by kwb Quote
I've never seen K-NIK adapter but it seems to have a lens element.
Any of these adapters will have a glass element, which concentrates light - that is why a 50mm f/1.4 lens should become approximately a true 25mm f/0.7 lens.



08-05-2020, 01:28 PM   #50
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QuoteOriginally posted by lytrytyr Quote
For the "equivalent" focal lengths,
I think you may be dividing, when you should be multiplying.

So the DA 35 Ltd should roughly translate to an FF 85/1.4.
But the bokeh might be strange at portrait distances or longer.
He is specifying the true values.
A 35mm f/2 should become a true 17.5mm f/1 lens, which will make it act exactly as a '06' lens set just above the lowest focal length if it could open to f/1.
I hope to try it with my eight-element "Super Takumar" 50mm f/1.4 lens, which should make it a true 25mm f/0.7 lens - assuming I can find uses for a 25mm Q-mount lens.
08-05-2020, 04:10 PM   #51
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QuoteOriginally posted by reh321 Quote
Any of these adapters will have a glass element, which concentrates light - that is why a 50mm f/1.4 lens should become approximately a true 25mm f/0.7 lens.
In the sentence you quoted ("I've never seen K-NIK adapter but it seems to have a lens element."), I was talking about whether or not K-NIK adapter has a lens, I was not talking about Q666. I asked and answered that question as a response to boojum's comment about muddiness because a lens in an adapter like K-NIK could reduce the contrast relative to a similar adapter without a lens due to unwanted lens reflections falling on the sensor via spurious paths.
08-05-2020, 04:20 PM - 1 Like   #52
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QuoteOriginally posted by reh321 Quote
Any of these adapters will have a glass element, which concentrates light - that is why a 50mm f/1.4 lens should become approximately a true 25mm f/0.7 lens.
That adapter isn't a telecompressor; I believe the only reason it has an optical element is because the flange distance between F and K mount is basically the same, so an optical element is necessary for infinity-focusing if your adapter is adding distance between the lens and focus plane. If it shrunk the image like a telecompressor, you'd end up with heavy vignetting and a smaller usable frame.

08-05-2020, 05:14 PM   #53
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As a reality check,
there's still no mention of a K-mount to Q-mount speedbooster
where it really counts, on the Metabones product list:

Metabones®
08-05-2020, 06:15 PM   #54
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QuoteOriginally posted by Sykil Quote
That adapter isn't a telecompressor; I believe the only reason it has an optical element is because the flange distance between F and K mount is basically the same, so an optical element is necessary for infinity-focusing if your adapter is adding distance between the lens and focus plane. If it shrunk the image like a telecompressor, you'd end up with heavy vignetting and a smaller usable frame.
Isn't it though? It's a focal reducer -- that's the way it gets it "speed boost", right? And you won't get vignetting because they are K lenses using the tiny Q sensor so there is plenty of leeway there.
08-05-2020, 06:33 PM   #55
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QuoteOriginally posted by vonBaloney Quote
Isn't it though? It's a focal reducer -- that's the way it gets it "speed boost", right? And you won't get vignetting because they are K lenses using the tiny Q sensor so there is plenty of leeway there.
I think the quote was referring to the K-NIK (K-mount to Nikon G) adapter,
which was just one of three optical systems in front of those muddy images.
08-05-2020, 06:45 PM   #56
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QuoteOriginally posted by lytrytyr Quote
I think the quote was referring to the K-NIK (K-mount to Nikon G) adapter,
which was just one of three optical systems in front of those muddy images.
Oh, *that* adapter, not *this* adapter...ok.
08-05-2020, 07:04 PM   #57
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QuoteOriginally posted by lytrytyr Quote
I think the quote was referring to the K-NIK (K-mount to Nikon G) adapter,
which was just one of three optical systems in front of those muddy images.
No, my comments were about the K-to-Q ‘focal reducer’ ..... I guess I used confusing words because several different adapters are being discussed in the same thread.
08-05-2020, 07:59 PM   #58
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Ok, to be clear the metabones device for Pentax K to Q (that doesn't exist) is in-fact a focal reducer -- same thing as a "telecompressor" I guess. But it shouldn't vignette as I noted because these are lenses for a bigger format -- that's the whole thing that allows it to work.
08-05-2020, 08:01 PM   #59
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QuoteOriginally posted by reh321 Quote
No, my comments were about the K-to-Q ‘focal reducer’ ..... I guess I used confusing words because several different adapters are being discussed in the same thread.
The person you quoted to correct wasn't talking about the Metabones speed booster, though.
08-06-2020, 09:32 AM   #60
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QuoteOriginally posted by Sykil Quote
The person you quoted to correct wasn't talking about the Metabones speed booster, though.
OK, I was confused. I didn't see any point to what I would call a K-to-F adapter.
The already existing F-to-Q adapter is more relevant, and is conceptually the same also.

I just want mine to be shipped!
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