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Forum: Pentax Q 4 Days Ago  
Pentax Q Copyright info setting
Posted By Abbazz
Replies: 3
Views: 297
You can also use ExifTool, which is free software. It is a very powerful application which lets you add or edit Exif fields effortless over entire directories.

Cheers!

Abbazz
Forum: Pentax Q 5 Days Ago  
Fish-Eye Options for the Q
Posted By Abbazz
Replies: 10
Views: 462
Congrats on the Fuji!

I had the same issue when i received mine. Apparently, the lens is bonded to the chrome ring with some kind of cement. I got to unscrew it by heating the mount with a hair dryer and applying some extra force with hand tools. I wrapped the lens in fabric to prevent it from being scratched but nonetheless made a small mark next to the mount.

It's a very good lens and well worth the fight! Go for it!

Cheers!

Abbazz
Forum: Pentax Q 04-12-2018, 04:46 PM  
So, is the Q still supported?
Posted By Abbazz
Replies: 120
Views: 8,630
Brian Caldwell of Metabones fame has explained that this particular Speed Booster was made just to prove that it was possible to make it. A 0.5x focal reducer can only be built for the Pentax Q mount, because such a device needs to be physically very close to the focus plane, which is made possible by the very short the registration of the Q mount and lack of a focal plane shutter. Also, the small size of the Q sensor mitigates the problems caused by marginal rays bending and the fact it is back-illuminated minimizes pixel vignetting effects.

I don't think Metabones will earn any money from it. Basically, it's just a kind of prototype assembled in a very small batch mainly from existing parts and that's the reason why it is only available in Nikon F/G mount.

Cheers!

Abbazz
Forum: Pentax Q 03-26-2018, 02:32 PM  
Q7 dr
Posted By Abbazz
Replies: 5
Views: 506
The dynamic range of the Q7 is much better than most people imagine. Here's the DPReview comparison between the Q7 (in green), the full frame Sony a7s (first generation), the M4/3 Panasonic GM1 and the 1" Sony RX100 (with the dynamic range optimization activated for all of them):



I you look at the highlights, the Q7 equals the Sony and beats both other cameras. For the shadows, it does actually outperform the three competitors. Please note that all three competitors have a much bigger sensor than the Q7 and that both the Panasonic GM1 and Sony A7s are more recent cameras than the Pentax Q7.

Cheers!

Abbazz
Forum: Pentax Q 01-16-2018, 06:01 PM  
Losing Date, Camera Reset??
Posted By Abbazz
Replies: 24
Views: 1,914
I have two Pentax Q, one Q7 and two Q-S1 bodies. The original Qs and the Q7 have always exhibited the same behavior: there is hardly enough time to switch the battery before the internal clock runs out of juice, thus requiring the user to set the date and time.At the same time, both Q-S1s retain the date and time for a much longer period (at least a few hours) when there is no battery. I have never heard of a Q-S1 suffering from time amnesia so there must have been some change in the latest model circuitry.

My guess is that the first models had an internal clock supplied by some kind of small capacitor charged by the battery. The capacitor was only able to supply power to the clock during a limited time, especially when the battery that was previously inside the camera was partially or totally discharged, meaning its voltage was under the nominal specs. On the other hand, the Q-S1 might have a proper backup battery, which is able to supply more power at a constant voltage.

Cheers!

Abbazz
Forum: Pentax Q 01-09-2018, 06:10 PM  
0.666 Devil's Speed Booster for Pentax Q
Posted By Abbazz
Replies: 15
Views: 2,320
Thanks for the compliment!

Cheers!

Abbazz
Forum: Pentax Q 01-07-2018, 04:04 PM  
Anybody hear about this metabones adapter? f/0.666???
Posted By Abbazz
Replies: 6
Views: 1,167
I have this adapter and am very happy with the results.

Here's a quick review that I have posted here: 0.666 Devil's Speed Booster for Pentax Q - PentaxForums.com

And a thread on another forum: Nikkor-S 55mm F/1.2 on Pentax Q with Devil's Speed Booster

Cheers!

Abbazz
Forum: Pentax Q 12-11-2017, 01:47 AM  
0.666 Devil's Speed Booster for Pentax Q
Posted By Abbazz
Replies: 15
Views: 2,320
You're welcome.


Of course it's not a pocket rig but the 55/1.2 lens on the SpeedBooster doesn't look ridiculously big on the Q:





Cheers!

Abbazz
Forum: Pentax Q 11-18-2017, 09:30 AM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
Thank you for the kind words, Boris!

Cheers!

Abbazz
Forum: Pentax Q 11-18-2017, 02:25 AM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
A few pictures taken wide open with the Kern Switar 13mm f/0.9 lens:













Cheers!

Abbazz
Forum: Pentax Q 11-17-2017, 02:11 AM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
WOW! Wonderful picture!

Thanks for sharing.

I have the 12.5/1.4 and 25/1.4 C-mount Pentax lenses and they are nowhere near as good as your 16/1.4 lens...

Cheers!

Abbazz
Forum: Pentax Q 11-16-2017, 06:47 PM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
Nice! Is this the C-mount lens?

Cheers!

Abbazz
Forum: Pentax Q 11-15-2017, 04:14 AM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
You're welcome!

The original Canon 50/0.95 lens for the Canon 7 camera had the cutout in the rear element; only one version of the TV lens had an intact rear element. Here's the bayonet of the original lens for Canon 7:



Here's the bayonet of my lens:



You can see the RF coupling cam at the top of the picture. The rear element beneath is intact. Also, the tech who did the mod retained part of the "ears" that you can see on the original lens above, in order to allow the user to depress the lens lock lever. Because of the large diameter of this lens, the lens lock lever on the Leica cameras is completely covered by the lens when it is mounted, thus preventing the user to unlock the lens. The metal part on the right of the picture allows the user to activate the lens lock lever.



Here's the lens on the tiny Q-S1:





And, as a comparison, the Nikkor-S 55/1.2 with the Devil's Speed Booster:





Sorry for the dust on the lenses and for the poor pictures, taken under my LED desk lamp while testing a (new to me) Vivitar 135/2.8 Close Focusing.

Cheers!

Abbazz
Forum: Pentax Q 11-14-2017, 10:00 PM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
I'll try with both sensors and let you know.


Mine is the "TV" version which has been converted to Leica-M mount. The conversion is clean (it was performed by Eastcamtech, who seems to be out of business now) and the lens is RF-coupled.The conversion was done without the butchered rear element:


Credit: Eastcamtech

This is better than the original Canon 7 mount lens and also than most conversions, which have an incomplete rear element in order to leave room for the RF cam:


Credit: JapanCameraHunter

Cheers!

Abbazz
Forum: Pentax Q 11-14-2017, 04:41 PM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
I will try to do some comparison shots with the 55/1.2 Nikkor and 50/0.95 Canon lenses.

I normally use the Canon "dream lens" on 24x36 "full-frame" bodies, either film or digital, because I feel its character is more pleasant when used over the whole frame rather than on smaller cropped formats. For example, check the wonderful and bokehlicious pictures taken by photographer Paul Marbrook: Sony A7 with Canon 50mm f/0.95 Dream Lens

Cheers!

Abbazz
Forum: Pentax Q 11-14-2017, 03:58 AM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
Here are a few shots with the Nikkor 55/1.2 mounted on the Devil's Speed Booster. All pictures taken at F/1.0 (F/2.0 on the lens); click on any picture to view it full-size:











I know some of you may ask: why F/1.0 (F/2.0 on the lens) and not F/0.666 (F/1.2 on the lens), as allowed by the DSB? The answer is quite simple. It's just because F/1.2 on the Nikkor suffers from spherical aberration and coma. There is also a lot of purple fringing. As a consequence, pictures have rather poor sharpness rapidly decreasing from the center to the edges, very low contrast and a purplish color balance that is not easy to correct. Here are two shots, the first one taken wide open (F/1.2 on the lens) and the second one at F/2.0:





And yes, the wide open picture is not too bad because I did my best to enhance the picture (I boosted contrast and clarity, corrected color balance and chromatic aberration). You can actually see the effect of coma on the edge of the distant leaf, even on a web sized picture. So, I prefer to shoot this lens stopped down to F/2.0, although the seven blade aperture does sometimes show in the bokeh as a consequence. F/1.2 is only usable for very low light shots (like candlelight dinners or night photography under street lights), where a centered subject and high contrast lighting will help mitigate the lens' defects.

Cheers!

Abbazz

PS: I would love to use my Canon 50/0.95 lens with a Speed Booster!
Forum: Pentax Q 11-11-2017, 04:15 AM  
Show us some bokeh - BoQeh? - from your Q!
Posted By Abbazz
Replies: 33
Views: 2,927
Very nice picture, Boris!

The 06 telephoto zoom is very capable of delivering out of focus backgrounds, especially when used at the far end of the zoom range (45mm), near wide open and and close to the subject. In fact, this lens has a very beautiful bokeh, with nicely shaped highlights. Here are a few recent pictures of our Southern Hemisphere Spring (check them full size by clicking on the pictures).

1:


2 (do you see the aphids ?);


3:


$4:


5:


6:


7:


8:


The 06 lens really something special: the lens is sharp enough over the whole field to be used wide open from 15mm to 45mm, it is absolutely free from lateral chromatic aberration, has very low vignetting and distortion. The above pictures have not been corrected for chromatic aberration, vignetting or distortion. That's not too shabby for an f/2.8 telephoto zoom that trades for less than $200 and is fully usable wide open! To get the same results from my Sony A7II, I would have to spend a lot more money...

Cheers!

Abbazz

[EDIT] Sorry, I just noticed that vignetting and distortion corrections were automatically applied in Adobe Camera Raw. But even without the corrections, the 06 telephoto zoom is perfectly able to deliver beautiful, clean pictures. Abbazz
Forum: Pentax Q 10-21-2017, 11:42 PM  
Let's share shots with Q!
Posted By Abbazz
Replies: 5,771
Views: 808,197
I just did the test and I got 1/1250s at f/1.2 with the focal reducer (F/0.666) and 1/400 at f/1.4 without it. That's a little bit less than 2 stops but the picture taken with the focal reducer looks overexposed, so I guess there are indeed two stops between them!

Here are the two shots:





Cheers!

Abbazz

[EDIT] Forgot to add: The picture was taken after sunset, hence the 1/400s at f/1.4.
Forum: Pentax Q 10-20-2017, 11:32 AM  
0.666 Devil's Speed Booster for Pentax Q
Posted By Abbazz
Replies: 15
Views: 2,320
Thank you for the kind words, barondla. :o

Cheers!

Abbazz

---------- Post added 20th Oct 2017 at 20:46 ----------


You're welcome. I must admit that I have been surprised by the image quality of this focal reducer, when I read on another forum that even Brian Caldwell, its creator, seemed to consider it as some kind of weird prototype released mainly for the collectors:



Cheers!

Abbazz

---------- Post added 20th Oct 2017 at 20:57 ----------


My pleasure! I sure hope the DSB will be released in K-mount soon. It's a shame the K-mount version was not released first, because it is of greater interest for us Pentaxians. And those old Nikkor lenses can be mounted on a Pentax K bayonet without any adapter but the reverse is not true.

Cheers,

Abbazz

---------- Post added 20th Oct 2017 at 21:15 ----------


You're welcome. I will try to find a model and shoot a few portraits.


I am not very keen on this "equivalence" stuff, which I find very confusing for newbies, but I think a 27.5mm f/1.0 lens on an 1/1.7" sensor would rather be something like a 127mm f/2.3 on a 24x36 sensor and an 84mm f/1.5 lens on an APS-C sensor.

Cheers!

Abbazz
Forum: Pentax Q 10-20-2017, 04:25 AM  
0.666 Devil's Speed Booster for Pentax Q
Posted By Abbazz
Replies: 15
Views: 2,320
Yes, the lateral chromatic aberration can be fixed very easily with most image editors. Even the ugly purple fringing can be fixed on most of the pictures. Converting to black and white is always possible for the desperate cases!

Cheers!

Abbazz
Forum: Pentax Q 10-20-2017, 03:14 AM  
0.666 Devil's Speed Booster for Pentax Q
Posted By Abbazz
Replies: 15
Views: 2,320
The 0.666 Devil's Speed Booster is a focal reducer specially crafted for the Pentax Q series. It has the unique ability to reduce the focal length of any lens mounted by half, and at the same time to increase its aperture by two stops. Other focal reducers for APS-C or M4/3 cameras only go to x0.71 and allow to increase the aperture by 1 stop.

The very short register of the Pentax Q mount allowed Metabones' Brian Caldwell to create this pretty extreme focal reducer. To maintain acceptable image quality, the maximum aperture had to be limited to F/0.666. Therefore, any lens with an aperture brighter than F/1.3 will have its aperture limited to F/0.666 when used with this focal reducer (hence its name).

For the moment, the Devil's Speed Booster (DSB) is only available in Nikon F mount, but a Pentax K version has also been announced.

The question is: does this clever contraption really work and is it any good? To try to answer this, I used a Pentax Q-S1 with my old Nikkor-S 55mm F/1.2 and did two series of test shots of a ColorChecker chart taken from about 3 meters. The first one was made with the lens on a plain Nikon to Pentax Q adapter and the second one with the lens on the DSB. Here are the JPEGs straight from the camera (you can click on the pictures to display them full size).

55mm F/1.2:


At F/1.2 this old lens is not very sharp and exhibits lots of aberrations. The field curvature is very strong.

55mm F/2.0:


It's already much better.

55mm F/2.8:


55mm F/4.0:


55mm F/5.6:


55mm F/8.0:


At F/8.0, the image is good but we begin to see the effects of diffraction on the small sensor of the Q-S1.

Now, let's try the same lens with the DSB, First, wide open, 27.5mm F/0.666:


No miracle here, there are still plenty of aberrations. But I have two remarks: first, image quality wide open is not worse than without the DSB (no added vignetting), it's even a tiny bit better from a sharpness point of view, and secondly, the aperture is really F/0.666. If you look at the EXIF of the picture taken wide open without the DSB, the speed is 1/2500s for an aperture of F/1.2. With the DSB, the speed is 1/8000s (and the picture is a bit overexposed because 1/8000s is the top speed of the Pentax Q-S1), which means there is a gain of almost two stops, as per the specs.

27.5mm F/1.0:


Image quality begins to increase.

27.5mm F/1.4:


F/1.4 is already quite good (even though there is still some chromatism).

27.5mm F/2.0:


27.5mm F/2.8:


27.5mm F/4.0:


At F/4.0 the image is sharp over the whole field and we are still below the diffraction zone of the small sensor. There is added lateral chromatic aberration though.

Here are some pictures taken at F/1.4 with the DSB (F/2.8 on the aperture ring of the lens):



Check the part of the blossom that is in focus and you will see that the sharpness is impressive at F/1.4!







The bokeh is not bad either...













And to conclude, two pictures taken at infinity at F/4.0 (F/8.0 on the aperture ring of the lens); don't forget that these are JPEGs straight from the camera with no post-processing whatsoever:





As a conclusion, I think the DSB is an interesting product. It makes vintage SLR lenses more usable on Q series cameras because it reduces greatly the crop factor (from 5.6 to 2.8 on the Q and Q10; from 4.6 to 2.3 on the Q7 and Q-S1) and also because it helps keeping the aperture below the diffraction zone. The DSB doesn't impact significantly vignetting (which is very low anyway because we only use the center part of the image circle of the lens) or sharpness. It does add a significant amount of lateral chromatic aberration though. As for shooting at F/0.666, it can be done in a pinch, but it will require quite a lot of post processing. One way to avoid having to deal with color shifts and chromatism is to convert your pictures to black and white.

Cheers!

Abbazz
Forum: Pentax Q 10-18-2017, 01:51 AM  
Let's share shots with Q!
Posted By Abbazz
Replies: 5,771
Views: 808,197
Personally, I would be extatic if MS Optical could manufacture another batch of the elusive MS-Optical Sonnetar 25mm f/1.1 for Pentax Q...

Cheers!

Abbazz
Forum: Pentax Q 10-17-2017, 04:34 AM  
Let's share shots with Q!
Posted By Abbazz
Replies: 5,771
Views: 808,197
Thank you, barondla, for the kind words. My previous picture (admittedly taken in bad light, under light rain) was heavily edited with Silver Efex II. Here's the straight out of camera color JPEG:


And here is the raw file edited to taste:



The adapter has been available since the end of August 2017. The adapter itself is quite good and its results depend mainly of the lens it is used with. Of course the crop factor of the Q tend to amplify the defects of any lens. With the Speed Booster, the crop factor is x2.3 for a Q7 or Q-S1 or x2.8 for a Q or Q10, so you'd better get a good lens to begin with. But even with the old 55/1.2 Nikkor, which does exhibit lots of colorful aberrations wide open, this Speed Booster is able to deliver some nice black and white portraits or stage photos in available light conditions.

I am sorry but I have no time right now for a review, but I will try to post something on next week-end, which happens to be Labour Day here.

Cheers!

Abbazz
Forum: Pentax Q 10-12-2017, 01:36 AM  
Let's share shots with Q!
Posted By Abbazz
Replies: 5,771
Views: 808,197

Nikkor-S 55mm F/1.2 wide open with Speed Booster -> 27.5mm F/0.67

Cheers!

Abbazz
Forum: Pentax Q 08-28-2017, 11:44 PM  
So, is the Q still supported?
Posted By Abbazz
Replies: 120
Views: 8,630
Just found this: Pentax Q discontinued? - PentaxForums.com (it's from 2012...)
:p

Cheers!

Abbazz
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