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01-22-2018, 10:22 PM - 1 Like   #16
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I have NO F-mount lenses. Do we have any idea when a K-mount variant will be available?? Only then will I have any incentive to even think about this thing

06-13-2018, 11:39 PM - 1 Like   #17
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QuoteOriginally posted by reh321 Quote
I have NO F-mount lenses. Do we have any idea when a K-mount variant will be available?? Only then will I have any incentive to even think about this thing
Back when I was shopping around for a Cine camera, I emailed Metabones and asked if there any plans to support K-mount lenses, and was told flatly and in no uncertain terms, that they will never support Pentax lenses.
That they made this product for Nikon lenses instead of Pentax lenses means that they must consider the Pentax lenses inferior, or that they expect Q owners to prefer non-Pentax lenses are better.

Fotodiox and their new Tilt-Rokr product, do similar - they made it for Pentax 6x7 lenses, but no K-mount version, Nikon, Canon, Sony versions, but nothing for Pentax camera owners.

Pretty silly logic - who is most likely to buy either the Metabones for Q, and the Tilt-Rokr for 6x7 lenses? - Pentax Camera and Lens owners!
We're more likely to own the lenses and the bodies these product are designed for, so they've ignored the biggest potential markets for them.


(rant Ends)


There is a glaring error in the OP,... the lens used is a Nikkor-S 55mm F/1.2.
This means on a FF camera, its a 55mm.

On the Speedbooster, it DOES NOT become the quoted 27.5mm lens.

Using the Q7 crop factor of 4.7, the 55mm with straight lens adapter is equivalent to 258.5mm

Data from Metabones site indicates the Q7 with the speedbooster fitted has it's crop factor reduced to 2.3, whereby the 55mm lens becomes the equivalent of a 126.5mm lens.


It is important to note that no focal reducer (the class of devices the speedbooster brand is) makes any lens Wider then it's native view angle. Ever.

Focal Reducers lower the percentage of the lens view angle lost due to the crop.
06-14-2018, 03:46 AM - 1 Like   #18
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QuoteOriginally posted by PiDicus Rex Quote
There is a glaring error in the OP,...
Thank you for your discourteous comment but I am very careful in my choice of words and I am pretty confident there is no error in my post.

QuoteOriginally posted by PiDicus Rex Quote
the lens used is a Nikkor-S 55mm F/1.2.
This means on a FF camera, its a 55mm.

On the Speedbooster, it DOES NOT become the quoted 27.5mm lens.

Using the Q7 crop factor of 4.7, the 55mm with straight lens adapter is equivalent to 258.5mm

Data from Metabones site indicates the Q7 with the speedbooster fitted has it's crop factor reduced to 2.3, whereby the 55mm lens becomes the equivalent of a 126.5mm lens.


It is important to note that no focal reducer (the class of devices the speedbooster brand is) makes any lens Wider then it's native view angle. Ever.

Focal Reducers lower the percentage of the lens view angle lost due to the crop.
"Equivalent focal length" corresponds to no physical measure. It's only a way to remember easily the field of view of a lens on different formats: a 55mm lens on a full frame sensor is "equivalent" to a 27.5mm lens on a M4/3 format sensor. It means that both lenses have the same field of view but not that the effective focal length of the lens changes according to the size of the sensor.

Regarding the false assumption that "no focal reducer makes any lens Wider then [sic] it's [sic] native view angle", see also my answer here.

Cheers!

Abbazz
06-14-2018, 04:41 AM - 1 Like   #19
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QuoteOriginally posted by PiDicus Rex Quote
There is a glaring error in the OP,... the lens used is a Nikkor-S 55mm F/1.2.
This means on a FF camera, its a 55mm.

On the Speedbooster, it DOES NOT become the quoted 27.5mm lens.

Using the Q7 crop factor of 4.7, the 55mm with straight lens adapter is equivalent to 258.5mm

Data from Metabones site indicates the Q7 with the speedbooster fitted has it's crop factor reduced to 2.3, whereby the 55mm lens becomes the equivalent of a 126.5mm lens.


It is important to note that no focal reducer (the class of devices the speedbooster brand is) makes any lens Wider then it's native view angle. Ever.

Focal Reducers lower the percentage of the lens view angle lost due to the crop.
No, the error is here.

The speedbooster does physically change the optical characteristics of the lens; light does follow a different path than it had. A 55mm lens does become a 27.5mm lens, because the path of light through it is changed.
Any lens becomes wider and it delivers a higher intensity beam to the sensor. Always.



What happens after that is different. On my Q-7, a 55mm lens acts like a 165mm lens acts on my K-30; the lens's characteristics don't change, the light still follows the same path, but how it is interpreted by the camera does.

06-21-2018, 06:57 AM - 1 Like   #20
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I'm wondering why they only manufacture it for Nikon mount? I suspect K-mount would have sold much better. At least I would have been much more interrested. I have a few nice pre-AI nikons, but many more in K or m42. Am I wrong to think that Q-owners more typically are Pentaxians with a bunch of Pentax/Takumar lenses in the closset, rather than old Nikonians? And with the slightly longer registration distance of the Nikon mount, it is hard to add another adapter on it to adapt to another lens mount, without adding more optics that likely degrade the results.

But thanks for posting an interesting review.

As this is my first post on the Q-subforum, I suppose I should admit that I happened to buy a red Q10 2nd had for very little a week ago. It comes with the 01, 02, 04 (which doesn't impress) and 07.
Right now I'm shopping adapters to see what is worth trying on the Q10 of my lens collection: through the viewfinder: My Lenses
06-21-2018, 03:06 PM - 1 Like   #21
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QuoteOriginally posted by Douglas_of_Sweden Quote
As this is my first post on the Q-subforum, I suppose I should admit that I happened to buy a red Q10 2nd had for very little a week ago. It comes with the 01, 02, 04 (which doesn't impress) and 07.
Right now I'm shopping adapters to see what is worth trying on the Q10 of my lens collection: through the viewfinder: My Lenses
Before you dismiss the 04, do try it out as a close-up lens. That seems to be its main appeal...

Cheers

Jonathan

Last edited by h4yn0nnym0u5e; 06-21-2018 at 03:08 PM. Reason: Quote only what I'm replying to...
06-21-2018, 03:22 PM - 1 Like   #22
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QuoteOriginally posted by Douglas_of_Sweden Quote
I'm wondering why they only manufacture it for Nikon mount? I suspect K-mount would have sold much better. At least I would have been much more interrested. I have a few nice pre-AI nikons, but many more in K or m42. Am I wrong to think that Q-owners more typically are Pentaxians with a bunch of Pentax/Takumar lenses in the closset, rather than old Nikonians? And with the slightly longer registration distance of the Nikon mount, it is hard to add another adapter on it to adapt to another lens mount, without adding more optics that likely degrade the results.
Apparently, Metabones has created this particular SpeedBooster as an "exercise in style", or a demonstration of its savoir-faire, but it is certainly not going to sell like hot cakes (especially considering the Pentax Q line is now on life support from Pentax). Metabones does not offer any SpeedBooster for Pentax lenses, so the company would have to source K-Mount bayonets as a special order to built a Q666 for Pentax lenses. I don't think it's going to happen.

QuoteOriginally posted by Douglas_of_Sweden Quote
But thanks for posting an interesting review.
You're welcome!

QuoteOriginally posted by Douglas_of_Sweden Quote
As this is my first post on the Q-subforum, I suppose I should admit that I happened to buy a red Q10 2nd had for very little a week ago. It comes with the 01, 02, 04 (which doesn't impress) and 07.
Right now I'm shopping adapters to see what is worth trying on the Q10 of my lens collection: through the viewfinder: My Lenses
Congrats on the Q10. Be warned, these little marvels are addictive... I have now a complete collection of lenses and five bodies: two original Q, one Q7 and two Q-S1!

Cheers!

Abbazz
06-21-2018, 05:04 PM   #23
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QuoteOriginally posted by Abbazz Quote
Apparently, Metabones has created this particular SpeedBooster as an "exercise in style", or a demonstration of its savoir-faire, but it is certainly not going to sell like hot cakes (especially considering the Pentax Q line is now on life support from Pentax). Metabones does not offer any SpeedBooster for Pentax lenses, so the company would have to source K-Mount bayonets as a special order to built a Q666 for Pentax lenses. I don't think it's going to happen.
We should add that a K-mount variant was mentioned in the press release, and I heard mention of an M42-mount variant, but I'm very skeptical at this point. If they had either I would purchase it, but I'm not going to spend $400 on an adapter and then have to spend additional money on the lens. I do have some AdaptAll lenses that I guess could be used if I purchased a for-Nikon rear-end, but I'd have to talk a long time to convince myself.

06-21-2018, 05:06 PM   #24
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QuoteOriginally posted by Douglas_of_Sweden Quote
As this is my first post on the Q-subforum, I suppose I should admit that I happened to buy a red Q10 2nd had for very little a week ago. It comes with the 01, 02, 04 (which doesn't impress) and 07.
Right now I'm shopping adapters to see what is worth trying on the Q10 of my lens collection: through the viewfinder: My Lenses
Welcome to our tiny group

You might consider an '06' lens. Of the lenses I use with my {yellow} Q7, that is probably the best
06-22-2018, 08:35 PM - 1 Like   #25
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Forgive extreme naivety but what challenges are there to physically remove the Nikon Mount and swap in a PK Mount instead, should one of our more adventurous selves wish to attempt it? At least I don’t see any electronics in this Metabones speedbooster. Getting the mechanical aperture to translate perhaps is 2’nd on the to-do list.
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06-22-2018, 08:46 PM - 1 Like   #26
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QuoteOriginally posted by 2old4toys Quote
Forgive extreme naivety but what challenges are there to physically remove the Nikon Mount and swap in a PK Mount instead, should one of our more adventurous selves wish to attempt it? At least I don’t see any electronics in this Metabones speedbooster. Getting the mechanical aperture to translate perhaps is 2’nd on the to-do list.
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Are you suggesting that someone, some amateur here, spend $489 on one of these devices and then modify it so that provides a K-mount instead of a F-mount?
06-22-2018, 09:08 PM - 1 Like   #27
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QuoteOriginally posted by reh321 Quote
Are you suggesting that someone, some amateur here, spend $489 on one of these devices and then modify it so that provides a K-mount instead of a F-mount?
Exactly yes. If you want it badly enough... why not
06-23-2018, 04:01 AM   #28
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QuoteOriginally posted by 2old4toys Quote
Exactly yes. If you want it badly enough... why not
@Abbazz has actually handled this thing, so he'll be able to give a better answer than I can, but here is my answer. I implied part of my answer by the way I asked my follow up question. You are correct that you are taking purely mechanical work here - but this would be very precise work on a relatively expensive piece of metal. You would need to fashion a K-mount while removing 1.05 mm in length from the device; perhaps you could transplant the K-mount from some other adapter, but you would still need to make the distance work out right to get infinity focus. I'm not a good enough craftsman, and it's not that important to me.
06-23-2018, 05:08 AM - 1 Like   #29
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QuoteOriginally posted by reh321 Quote
@Abbazz would need to fashion a K-mount while removing 1.05 mm in length from the device; perhaps you could transplant the K-mount from some other adapter, but you would still need to make the distance work out right to get infinity focus.
Some services out there will help you swap out lens mounts. Making sure infinity focus works is part of their job. Admittedly this specific mod would be more involved/less requested as the camera body end has a pin mechanism and aperture control.

I am of course playing devils advocate but...

If I was really keen with lots of K mount glass at hand, I would start seeking out one of those folks to give an evaluation for a custom job. Much more likely to deliver what you want faster than asking Metabones to tool up for a mass market product roll out.
06-24-2018, 06:00 PM - 2 Likes   #30
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QuoteOriginally posted by reh321 Quote
@Abbazz has actually handled this thing, so he'll be able to give a better answer than I can, but here is my answer. I implied part of my answer by the way I asked my follow up question. You are correct that you are taking purely mechanical work here - but this would be very precise work on a relatively expensive piece of metal. You would need to fashion a K-mount while removing 1.05 mm in length from the device; perhaps you could transplant the K-mount from some other adapter, but you would still need to make the distance work out right to get infinity focus. I'm not a good enough craftsman, and it's not that important to me.
It must be doable but maybe not as easy as it seems.

When I received the Pentax Q SpeedBooster, it was not able to properly focus to infinity: max focus was about 30 meters, which makes quite a difference with a 55mm lens at F/1.2. I had to adjust the infinity focus as per the procedure outlined on the Metabones website. This was a bit tricky because I found out that if you oudo the adjustment just a little bit, it can prevent your SpeedBooster from focusing properly. But I guess it means you could replace the Nikon bayonet with a Pentax one and then carefully adjust the focus on the adapter to compensate for the small difference in backfocus between Nikon and Pentax mounts.

Maybe I will try it some day.

Cheers!

Abbazz
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