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Forum: Pentax Q 6 Days Ago  
0.666 Devil's Speed Booster for Pentax Q
Posted By Abbazz
Replies: 12
Views: 980
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 27
Views: 1,518
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: 5,703
Views: 778,414
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: 12
Views: 980
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: 12
Views: 980
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: 12
Views: 980
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: 5,703
Views: 778,414
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: 5,703
Views: 778,414
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: 5,703
Views: 778,414

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: 112
Views: 6,931
Just found this: Pentax Q discontinued? - PentaxForums.com (it's from 2012...)
:p

Cheers!

Abbazz
Forum: Pentax Q 08-25-2017, 12:16 PM  
So, is the Q still supported?
Posted By Abbazz
Replies: 112
Views: 6,931
Manufacturers of optics usually do not encourage users to buy adapters because they prefer to sell more new lenses rather than having the users recycling their old lenses.

Please note than many photographers use adapted lenses for professional work requiring high image quality and perfect reliability. I personally know quite a few guys doing paid work with Canon pro lenses on Sony full-frame cameras, because they need the better Sony sensors but cannot find the lens they need in the somewhat limited range Sony offers. Professional photographers are not masochistic: if they do so, it's because they get better results with their adapted lenses on a Sony camera that they would get with a native Canon body and can sell more of their pictures!

Quite a few manufacturers of high quality camera equipment are presently offering adapters or have offered them in the past in order to allow compatibility between different range of products or between different formats: Leica, Canon, Nikon, Pentax, Minolta and many others come to mind. People also have been using extension tubes and other contraptions sitting between the lens and camera body for decades for quality work.

So please stop your trolling about adapters not working. ADAPTERS.DO.WORK and pretty well in fact!

Cheers!

Abbazz
Forum: Pentax Q 08-24-2017, 09:49 PM  
Q construction
Posted By Abbazz
Replies: 16
Views: 1,177
I have two original Q, one Q7 and two Q-S1.

As far as I know, Pentax started to design an interchangeable lens mirrorless system in 2009-2010. At that time, other manufacturers competing to release a mirrorless camera opted for larger sensors (M4/3 for Olympus / Panasonic and APS/C for Sony), but Pentax chose to use a backside-illuminated 1/1.7" sensor (this was before the K-01). Unfortunately, at the time Pentax was ready to launch its Q model, Sony had not yet released the backside-illuminated 1/1.7" sensor and the only backlit sensor available that could fit inside the Q body was the smaller 1/2.33",

Pentax then had two options: either wait until the release of the larger 1/1.7" sensor, or market immediately a somewhat crippled camera with the smaller sensor. Because the newly released M4/3 cameras from Olympus and Panasonic, as well as the Sony Nex 3 and Nex 5 were making quite a hit on the market at that time, Pentax felt it had to move swiftly in order to grab a share of the new market. So it decided to go with the smaller 1/2.33" sensor. The Q was not a big success outside of Japan because of its initial price tag ($800), and also because its smaller sensor made it less competitive with regard to other mirrorless cameras (at least in the eyes of the professional reviewers).

The Q (or Q10) are not bad cameras in any way -in fact they are very good at certain tasks, like super-macro or super-telephoto shots- but they are not very attractive as a general purpose system, mainly because the few high quality native lenses available were designed with the larger sensor in mind. On the Q / Q10, the 02 standard zoom is a 28-83mm eq. lens, while on the Q7 / Q-S1 it's a 24-70mm eq, which many people will find a more attractive focal range. Same for the 01 standard prime, which is a 48mm eq. on the Q / Q10, while it's a more useful 39mm eq, on the Q7 / Q-S1.

As for the build quality, the original Q feels sturdier indeed with its nice magnesium body cover but the other models have a nice finish as well. They don't feel like cheap point-and-shoots at all and, as far as I can tell, seem quite durable.

So for me, the larger sensor is more useful and my favorite of the lot is the Q-S1. I think it feels more responsive and more polished than the previous models. Maybe it's only because it's the newest model after all, but I think there are also a few details that have been improved on the Q-S1. Like for example the capacity to retain the date and time with the battery out: on the previous models, I have to input the date and time every time I take out the battery for more than a few seconds, while the Q-S1 retains the date and time even when I take out the battery, charge it on the external charger and put it back inside the camera after a few hours.

Cheers!

Abbazz
Forum: Pentax Price Watch 08-22-2017, 01:51 PM  
HU Pentax FA 600mm f/4 on eBay
Posted By Abbazz
Replies: 8
Views: 1,387
For those who might be interested, there is an FA 600mm f/4 offered on eBay by a very reputable seller: smc PENTAX FA * 600mm f/4 ED IF Excellent+ | eBay
The price is a bit steep but don't forget it's a very rare lens...

Cheers!

Abbazz
Forum: Pentax SLR Lens Discussion 08-14-2017, 05:35 PM  
Getting Asahi Pentax Spotmatic in 2017?
Posted By Abbazz
Replies: 17
Views: 979
Spotmatics are among the best SLRs ever made.
Here are two recent posts by Michael Johnston about the Spotmatic:
The Online Photographer: So You Say You Want a Film Camera?
The Online Photographer: Three More Things About the Spotmatic

Cheers!

Abbazz
Forum: Pentax Compact Cameras 08-04-2017, 03:34 AM  
Point and Shoot Competition #116 - Summer evening
Posted By Abbazz
Replies: 45
Views: 2,514
Pentax Q-S1 with 01 lens:


Cheers!

Abbazz
Forum: Pentax Q 08-02-2017, 03:09 AM  
So, is the Q still supported?
Posted By Abbazz
Replies: 112
Views: 6,931
Forum: Pentax Compact Cameras 08-01-2017, 04:27 AM  
Point and Shoot Competition #115 - Vacation
Posted By Abbazz
Replies: 37
Views: 1,953
Bali, Pentax Q-S1 & Kern Switar 13/0.9:



Cheers!

Abbazz
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