Pentax Q - K-mount adapter !

rawr · 09-04-2011, 09:08 AM

Originally posted by snostorm

the equivalent actual FL on an APS-C camera for a lens on the K mount lens on a Q is 3.61x.

Sorry. My maths was of course wrong.

Originally posted by snostorm

I don't know if the SR works with MF lenses.

Hopefully it will. Maybe it's just a firmware update away ... Anyway, image stabilization whilst shooting on a solid tripod isn't so important, and is normally not something one would use.

But for those scenarios when shooting 1100mm or above handheld using the Q, image stabilisation would certainly be handy

snostorm · 09-04-2011, 10:36 AM - **3 Likes**

Originally posted by maxfield_photo

WOW, it's SO compact!! Now I can fit it in my pocket and take it anywhere.

(If you haven't guessed, I still fail to see the point of the Q)

Originally posted by Christopher M.W.T

Hahha thats hilarious.

Originally posted by rparmar

Yep, this is just about the stupidest thing Pentax has ever done.

You're all so funny!!!

I suppose that shooting long tele is a bit beyond you. . .

Here's how it would work -- The Q + K-Q adapter could be used as a virtual 3.6x TC without the 3.6x stop loss of light that rear converter TCs normally cost. This means that a $600 100mm f2.8 which can be carried in a jacket pocket and weighs only 13 oz (add the Q body and the total is @ 20 oz) can be shot as as if it were a 361mm f2.8 lens on an APS-C or a 553mm f2.8 lens on a 36x24 sensored body. If your not aware of the size, weight, and cost of these lenses, the FA* 300 f2.8 uses a 112mm front filter (that's about 4.4 inches in diameter) and weighs in at @ 6 lbs 10 oz ready to shoot (and note that it offers 61mm less reach) -- and it would probably cost in the neighborhood of at least $5000 USD if available new now (figure @ $3000+ used). A lower cost alternative would be the Sigma EX 300 f2.8 APO which is maybe a lb lighter and costs a bit over $3000, but it's not quite as good as the FA*.

Compared to the closest thing for a 36x24 sensored body, the Sigma 200-500 f2.8 zoom weighs in at 35 lbs and costs @ $26,000 USD, and is big enough that you'd need something like a golf bag and cart to protect/transport it . The Sigma EX 500 f4 is a slower option, but still costs @ $4000 USD and weighs over 7 lbs.

The 300/2.8 class of lens is heavy enough that it's not really easily handholdable (take a gallon jug of water and hold it up to your eye like a camera to get an idea of what it's like), so good tripod support is necessary for any extended shooting. To do the job right, add a heavy duty CF tripod and a gimbal head @ something like $1000 if you get one of the cheaper tripods (plus it's about 10-12 lbs more gear to carry). For the Q, you could get comparable support with a CF tripod and quality ballhead in the 3-5 lb range total and probably a cost of $300-400.

Before you go back to the "but IQ would be better with APS-C" argument, I'll concede that you would be correct, I'll counter that by saying that saving about 13 lbs of system carrying weight (camera body, lens, and tripod/head) and about $5000 can be worth more of a tradeoff in IQ than the Q presents vs APS-C. For me, an investment of @ $1000 for the Q kit and K-Q adapter is really not a whole lot for the potential benefit it might bring. I can get out to 1020mm (1530mm EQ) with stacked TCs on a 300/2.8 (2 ea 1.4x TCs and a 1.7x AFA), but I have a max aperture of f9.3. With the Q + adapter and a 300/2.8, I'd have a 1659mm EQ lens that I can shoot at f2.8. Over three and a half stops advantage is nothing to sneeze at when shooting extreme tele (and the inevitable camera shake) at living creatures that don't listen when you ask them to stand still. Shooting at 1/1000 instead of something around 1/100 will make a bigger difference in final IQ than the IQ differences between the sensors, and that doesn't even take into account the optical resolution lost with the stacked TCs (which is actually not as extreme as most people think, but it's noticeable)

Even if it doesn't work as well as I hope --though zxaar's assessment of the IQ potential is pretty positive -- I'd still have a compact camera that seems to be at the top of the class for IQ, handling, and build quality for a compact. I've played around with the high ISO sample images that have been posted, and they are more than acceptable to me for the class of camera -- and I'd still have my K-5 for more serious work.

And then there are the potential benefits for macro shooting. . . I won't waste my time.

Laugh all you want. The Q has some serious potential as a photographic tool for me regardless if you can see the possibilities or not. It's possible that it can get me images that I wouldn't get with my present gear, and that's really what this is all about, isn't it?

Scott

jogiba · 09-04-2011, 12:00 PM

You Tube

hcarvalhoalves · 09-04-2011, 12:52 PM

Originally posted by jogiba

Looks interesting.

The adapter is bigger than the camera. WTF?

Also, putting K lenses on a Q body isn't "multiplying focal length". It's just wasting light from the image circle. What's the difference between this, and just center cropping an image taken in a K-something?

Last edited by hcarvalhoalves; 09-04-2011 at 12:58 PM.

gazonk · 09-04-2011, 12:55 PM

Originally posted by hcarvalhoalves

What's the difference between this, and just center cropping an image taken in a K-something?

Resolution - if the lens resolves well. A similar crop from the K-5 leaves you with only 1mp images.

Mistral75 · 09-04-2011, 12:58 PM

Originally posted by hcarvalhoalves

(...)

Also, putting K lenses on a Q body isn't "multiplying focal length". It's just wasting light from the image circle. What's the difference between this, and just center cropping an image taken in a K-something? Stupid.

The difference is that Q sensor's pixel density is much higher so, if you assume that the APS-C / FF lens you put in front of your Q is capable of the corresponding resolution, the result will be of much higher quality than a crop from an APS-C sensor.

hcarvalhoalves · 09-04-2011, 01:17 PM

Originally posted by Mistral75

The difference is that Q sensor's pixel density is much higher so, if you assume that the APS-C / FF lens you put in front of your Q is capable of the corresponding resolution, the result will be of much higher quality than a crop from an APS-C sensor.

Q's sensor features a higher pixel density (for a premium), but consider, for instance, the effects of diffraction and purple fringing. Even dust spots can be a nightmare in a sensor that size. I have my doubts if featuring an uncropped 12MP makes it automatically better IQ-wise for tele work.

Last edited by hcarvalhoalves; 09-04-2011 at 01:23 PM.

**rparmar** · 09-04-2011, 01:52 PM

Originally posted by rawr

But look what the K-mount adapter lets you do

What it lets me do is give up the quality of a relatively large APS-C sensor (23.60 x 15.70mm) for that of a tiny 6.17 x 4.55mm sensor. There is no measure by which that is an improvement.

Originally posted by snostorm

Laugh all you want. The Q has some serious potential as a photographic tool for me regardless if you can see the possibilities or not. It's possible that it can get me images that I wouldn't get with my present gear, and that's really what this is all about, isn't it?

You need to learn how equivalence works because currently you are spewing nonsense. There is no free ride. The "crop factor" means that with the Q you are shooting with only a fraction of the potential of the lens as it would be on APS-C.

That fraction happens to be 0.275. So my K20D is about four times more effective at capturing light than this toy camera.

If I want to crop the centre quarter out of the image and pretend I am shooting with the Q I can! Please tell me how it is a good thing that I have this choice forced on me for each and every shot.

jogiba · 09-04-2011, 02:35 PM

The Q should be great with Pentax C mount lenses like the Pentax 1/2" C Mount 8-48mm F1.0 Manual Zoom Lens that has an image circle made for the Q.
Pentax 1/2" C Mount 8-48mm F1.0 Manual Zoom Lens C60812 B&H

Pentax 8-48mm F1.0 Manual Zoom Lens on GH2:

The GH2 needs to use cropped ETC mode (1920x1080 px) .

spmcrq · 09-04-2011, 05:01 PM

talking about compact. Consider Q is a replacement of a lens, like DA300 or FA600. which one is more compact?

zxaar · 09-04-2011, 05:44 PM

Originally posted by rparmar

That fraction happens to be 0.275. So my K20D is about four times more effective at capturing light than this toy camera.

Talk is so cheap. Now prove it. All you have to do is show us that k20D is 2 stops better than Q. So far it does not seem to be the case. Q may very well be close to 20D than to modern sony APC sensors.

rawr · 09-04-2011, 06:09 PM

Excellent overview images of the KQ adapter here:

ƒyƒ“ƒ^ƒbƒNƒX�A�uKQƒ}ƒEƒ“ƒgƒAƒ_ƒvƒ^�[�v�i‰¼�Ì�j‚ð‘å�ã‚ÌPENTAX Q‘ÌŒ±ƒCƒxƒ“ƒg‚ÉŽQ�l�o•i - ƒfƒWƒJƒ�Watch

Looks like totally manual only and no electrical connectors visible.

Originally posted by rparmar

The "crop factor" means that with the Q you are shooting with only a fraction of the potential of the lens as it would be on APS-C.

Be that as it may, I think you are getting muddled by the issue of comparisons. Sure you may be dumping a ton of light and resolution potential by using a full size lens on the Q, but you just want a good feed of resolution and light from a small portion of the centre of the lens to hit the Q sensor.

So I think if you put good glass capable of delivering resolution X in front of a sensor capable of resolution x, DR y and colour depth z, you may expect OK images if the numbers for X, x y and z are OK. Since early lab tests (eg the TechRadar Q review) suggest the resolution, DR etc of the Q may be quite creditable, despite the small sensor size, all that is left then is good inputs from a quality lens and the total result should be OK. Not APS-C or FF quality, perhaps, but still OK.

**rparmar** · 09-04-2011, 06:53 PM

Originally posted by zxaar

Talk is so cheap. Now prove it. All you have to do is show us that k20D is 2 stops better than Q. So far it does not seem to be the case. Q may very well be close to 20D than to modern sony APC sensors.

My talk is cheap so you offer talk back? At least try to be consistent!

And really the comparison should not be to a two-generation old camera but to the K-5. But in any case you ignored the entire substance of what I wrote -- not surprisingly.

fuent104 · 09-04-2011, 06:54 PM

That video is stunning. It is a great piece of filmmaking, and is proof beyond a doubt that, in the hands of a talented and knowledgeable artist, it is a serious tool. I don't care what formulas anyone can show me about diffraction, etc...clearly the Q can be used to create something wonderful.

zxaar · 09-04-2011, 06:57 PM

Originally posted by rparmar

My talk is cheap so you offer talk back? At least try to be consistent!

And really the comparison should not be to a two-generation old camera but to the K-5. But in any case you ignored the entire substance of what I wrote -- not surprisingly.

Did you not say that k20d gathers 4 times more light. And did I not say that gap with modern sony APC would be larger than with k20d.

by the way even with modern APC cams, the difference is not going to be that large. Q sensor is not of same technology as sony APC sensor. Q sensor gather 20% more light, so things are not straight forward.

Now you have still not proved your assertion that k20D is 2 stops better than Q. You can take that back if you want. But until you do - talk is cheap . You are only words and no proof.

09-04-2011, 02:35 PM	#24
jogiba Banned Join Date: Sep 2006 Location: Millstone,NJ Posts: 6,491 Original Poster	$258.50 Pentax 8-48mm F1.0 Manual Zoom Lens The Q should be great with Pentax C mount lenses like the Pentax 1/2" C Mount 8-48mm F1.0 Manual Zoom Lens that has an image circle made for the Q. Pentax 1/2" C Mount 8-48mm F1.0 Manual Zoom Lens C60812 B&H Pentax 8-48mm F1.0 Manual Zoom Lens on GH2: The GH2 needs to use cropped ETC mode (1920x1080 px) .

09-04-2011, 06:09 PM	#27
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	Excellent overview images of the KQ adapter here: ƒyƒ“ƒ^ƒbƒNƒX�A�uKQƒ}ƒEƒ“ƒgƒAƒ_ƒvƒ^�[�v�i‰¼�Ì�j‚ð‘å�ã‚ÌPENTAX Q‘ÌŒ±ƒCƒxƒ“ƒg‚ÉŽQ�l�o•i - ƒfƒWƒJƒ�Watch Looks like totally manual only and no electrical connectors visible. Originally posted by rparmar The "crop factor" means that with the Q you are shooting with only a fraction of the potential of the lens as it would be on APS-C. Be that as it may, I think you are getting muddled by the issue of comparisons. Sure you may be dumping a ton of light and resolution potential by using a full size lens on the Q, but you just want a good feed of resolution and light from a small portion of the centre of the lens to hit the Q sensor. So I think if you put good glass capable of delivering resolution X in front of a sensor capable of resolution x, DR y and colour depth z, you may expect OK images if the numbers for X, x y and z are OK. Since early lab tests (eg the TechRadar Q review) suggest the resolution, DR etc of the Q may be quite creditable, despite the small sensor size, all that is left then is good inputs from a quality lens and the total result should be OK. Not APS-C or FF quality, perhaps, but still OK. Last edited by rawr; 09-04-2011 at 06:21 PM.

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09-04-2011, 09:08 AM	#16
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	Originally posted by snostorm the equivalent actual FL on an APS-C camera for a lens on the K mount lens on a Q is 3.61x. Sorry. My maths was of course wrong. Originally posted by snostorm I don't know if the SR works with MF lenses. Hopefully it will. Maybe it's just a firmware update away ... Anyway, image stabilization whilst shooting on a solid tripod isn't so important, and is normally not something one would use. But for those scenarios when shooting 1100mm or above handheld using the Q, image stabilisation would certainly be handy

09-04-2011, 10:36 AM - 3 Likes	#17
snostorm Veteran Member Join Date: Oct 2006 Location: Chicago suburb, IL, USA Posts: 1,535	Originally posted by maxfield_photo WOW, it's SO compact!! Now I can fit it in my pocket and take it anywhere. (If you haven't guessed, I still fail to see the point of the Q) Originally posted by Christopher M.W.T Hahha thats hilarious. Originally posted by rparmar Yep, this is just about the stupidest thing Pentax has ever done. You're all so funny!!! I suppose that shooting long tele is a bit beyond you. . . Here's how it would work -- The Q + K-Q adapter could be used as a virtual 3.6x TC without the 3.6x stop loss of light that rear converter TCs normally cost. This means that a $600 100mm f2.8 which can be carried in a jacket pocket and weighs only 13 oz (add the Q body and the total is @ 20 oz) can be shot as as if it were a 361mm f2.8 lens on an APS-C or a 553mm f2.8 lens on a 36x24 sensored body. If your not aware of the size, weight, and cost of these lenses, the FA* 300 f2.8 uses a 112mm front filter (that's about 4.4 inches in diameter) and weighs in at @ 6 lbs 10 oz ready to shoot (and note that it offers 61mm less reach) -- and it would probably cost in the neighborhood of at least $5000 USD if available new now (figure @ $3000+ used). A lower cost alternative would be the Sigma EX 300 f2.8 APO which is maybe a lb lighter and costs a bit over $3000, but it's not quite as good as the FA*. Compared to the closest thing for a 36x24 sensored body, the Sigma 200-500 f2.8 zoom weighs in at 35 lbs and costs @ $26,000 USD, and is big enough that you'd need something like a golf bag and cart to protect/transport it . The Sigma EX 500 f4 is a slower option, but still costs @ $4000 USD and weighs over 7 lbs. The 300/2.8 class of lens is heavy enough that it's not really easily handholdable (take a gallon jug of water and hold it up to your eye like a camera to get an idea of what it's like), so good tripod support is necessary for any extended shooting. To do the job right, add a heavy duty CF tripod and a gimbal head @ something like $1000 if you get one of the cheaper tripods (plus it's about 10-12 lbs more gear to carry). For the Q, you could get comparable support with a CF tripod and quality ballhead in the 3-5 lb range total and probably a cost of $300-400. Before you go back to the "but IQ would be better with APS-C" argument, I'll concede that you would be correct, I'll counter that by saying that saving about 13 lbs of system carrying weight (camera body, lens, and tripod/head) and about $5000 can be worth more of a tradeoff in IQ than the Q presents vs APS-C. For me, an investment of @ $1000 for the Q kit and K-Q adapter is really not a whole lot for the potential benefit it might bring. I can get out to 1020mm (1530mm EQ) with stacked TCs on a 300/2.8 (2 ea 1.4x TCs and a 1.7x AFA), but I have a max aperture of f9.3. With the Q + adapter and a 300/2.8, I'd have a 1659mm EQ lens that I can shoot at f2.8. Over three and a half stops advantage is nothing to sneeze at when shooting extreme tele (and the inevitable camera shake) at living creatures that don't listen when you ask them to stand still. Shooting at 1/1000 instead of something around 1/100 will make a bigger difference in final IQ than the IQ differences between the sensors, and that doesn't even take into account the optical resolution lost with the stacked TCs (which is actually not as extreme as most people think, but it's noticeable) Even if it doesn't work as well as I hope --though zxaar's assessment of the IQ potential is pretty positive -- I'd still have a compact camera that seems to be at the top of the class for IQ, handling, and build quality for a compact. I've played around with the high ISO sample images that have been posted, and they are more than acceptable to me for the class of camera -- and I'd still have my K-5 for more serious work. And then there are the potential benefits for macro shooting. . . I won't waste my time. Laugh all you want. The Q has some serious potential as a photographic tool for me regardless if you can see the possibilities or not. It's possible that it can get me images that I wouldn't get with my present gear, and that's really what this is all about, isn't it? Scott

09-04-2011, 12:52 PM	#19
hcarvalhoalves Pentaxian Join Date: Aug 2010 Location: São Paulo, Brazil Photos: Gallery Posts: 1,019	Originally posted by jogiba Looks interesting. The adapter is bigger than the camera. WTF? Also, putting K lenses on a Q body isn't "multiplying focal length". It's just wasting light from the image circle. What's the difference between this, and just center cropping an image taken in a K-something? Last edited by hcarvalhoalves; 09-04-2011 at 12:58 PM.

09-04-2011, 12:55 PM	#20
gazonk Pentaxian Join Date: Feb 2009 Location: Oslo area, Norway Photos: Gallery \| Albums Posts: 3,746	Originally posted by hcarvalhoalves What's the difference between this, and just center cropping an image taken in a K-something? Resolution - if the lens resolves well. A similar crop from the K-5 leaves you with only 1mp images.

09-04-2011, 12:58 PM	#21
Mistral75 Pentaxian Join Date: Feb 2009 Location: Paris, France Posts: 7,527	Originally posted by hcarvalhoalves (...) Also, putting K lenses on a Q body isn't "multiplying focal length". It's just wasting light from the image circle. What's the difference between this, and just center cropping an image taken in a K-something? Stupid. The difference is that Q sensor's pixel density is much higher so, if you assume that the APS-C / FF lens you put in front of your Q is capable of the corresponding resolution, the result will be of much higher quality than a crop from an APS-C sensor.

09-04-2011, 01:17 PM	#22
hcarvalhoalves Pentaxian Join Date: Aug 2010 Location: São Paulo, Brazil Photos: Gallery Posts: 1,019	Originally posted by Mistral75 The difference is that Q sensor's pixel density is much higher so, if you assume that the APS-C / FF lens you put in front of your Q is capable of the corresponding resolution, the result will be of much higher quality than a crop from an APS-C sensor. Q's sensor features a higher pixel density (for a premium), but consider, for instance, the effects of diffraction and purple fringing. Even dust spots can be a nightmare in a sensor that size. I have my doubts if featuring an uncropped 12MP makes it automatically better IQ-wise for tele work. Last edited by hcarvalhoalves; 09-04-2011 at 01:23 PM.

09-04-2011, 01:52 PM	#23
rparmar Site Supporter Join Date: Jan 2008 Photos: Gallery Posts: 8,819	Originally posted by rawr But look what the K-mount adapter lets you do What it lets me do is give up the quality of a relatively large APS-C sensor (23.60 x 15.70mm) for that of a tiny 6.17 x 4.55mm sensor. There is no measure by which that is an improvement. Originally posted by snostorm Laugh all you want. The Q has some serious potential as a photographic tool for me regardless if you can see the possibilities or not. It's possible that it can get me images that I wouldn't get with my present gear, and that's really what this is all about, isn't it? You need to learn how equivalence works because currently you are spewing nonsense. There is no free ride. The "crop factor" means that with the Q you are shooting with only a fraction of the potential of the lens as it would be on APS-C. That fraction happens to be 0.275. So my K20D is about four times more effective at capturing light than this toy camera. If I want to crop the centre quarter out of the image and pretend I am shooting with the Q I can! Please tell me how it is a good thing that I have this choice forced on me for each and every shot.

09-04-2011, 05:01 PM	#25
spmcrq New Member Join Date: May 2009 Location: Auckland Posts: 16	talking about compact. Consider Q is a replacement of a lens, like DA300 or FA600. which one is more compact?

09-04-2011, 05:44 PM	#26
zxaar Veteran Member Join Date: Jul 2009 Location: kobe/japan Posts: 510	Originally posted by rparmar That fraction happens to be 0.275. So my K20D is about four times more effective at capturing light than this toy camera. Talk is so cheap. Now prove it. All you have to do is show us that k20D is 2 stops better than Q. So far it does not seem to be the case. Q may very well be close to 20D than to modern sony APC sensors.

09-04-2011, 06:53 PM	#28
rparmar Site Supporter Join Date: Jan 2008 Photos: Gallery Posts: 8,819	Originally posted by zxaar Talk is so cheap. Now prove it. All you have to do is show us that k20D is 2 stops better than Q. So far it does not seem to be the case. Q may very well be close to 20D than to modern sony APC sensors. My talk is cheap so you offer talk back? At least try to be consistent! And really the comparison should not be to a two-generation old camera but to the K-5. But in any case you ignored the entire substance of what I wrote -- not surprisingly.

09-04-2011, 06:54 PM	#29
fuent104 Veteran Member Join Date: Apr 2011 Location: California Photos: Gallery Posts: 1,356	That video is stunning. It is a great piece of filmmaking, and is proof beyond a doubt that, in the hands of a talented and knowledgeable artist, it is a serious tool. I don't care what formulas anyone can show me about diffraction, etc...clearly the Q can be used to create something wonderful.

09-04-2011, 06:57 PM	#30
zxaar Veteran Member Join Date: Jul 2009 Location: kobe/japan Posts: 510	Originally posted by rparmar My talk is cheap so you offer talk back? At least try to be consistent! And really the comparison should not be to a two-generation old camera but to the K-5. But in any case you ignored the entire substance of what I wrote -- not surprisingly. Did you not say that k20d gathers 4 times more light. And did I not say that gap with modern sony APC would be larger than with k20d. by the way even with modern APC cams, the difference is not going to be that large. Q sensor is not of same technology as sony APC sensor. Q sensor gather 20% more light, so things are not straight forward. Now you have still not proved your assertion that k20D is 2 stops better than Q. You can take that back if you want. But until you do - talk is cheap . You are only words and no proof.