Downside to K20D

happicamper · 05-26-2008, 08:30 PM

I agree, the 18-250 is a very good lens with the right amount light. I bought it as my kit lens with the camera. I had a rough work out at first when only able to get out and shoot in low light mid winter afternoon conditions. I realized that I had quite a learning curve to get to know this lens and camera. Happy to report now that I've had some very nice results with this lens in good lighting.

I recently picked up the 50-135 for much the same reason as you and had my first opportunity to really use it last weekend. Sweet lens and very sharp. My current kit is very similar to yours less the K20 and macro.

Cindy

PentaxPoke · 05-26-2008, 08:38 PM

Sounds like we have gone down the same lens buying path...I just ordered the DA* 16-50 and that will be my last lens purchase for a looong time. So much of my shooting is indoors in lower light, hence my insatiable appetite for f2.8 and lower lenses.

ll_coffee_lP · 05-27-2008, 10:34 AM

Great test...and thanks for taking the time to display your results!

One quick question though for photos 5-7. Is that a shotgun shell just above the bulldozer in the photos?

c[_]

PentaxPoke · 05-27-2008, 12:20 PM

Originally posted by ll_coffee_lP

Great test...and thanks for taking the time to display your results!

One quick question though for photos 5-7. Is that a shotgun shell just above the bulldozer in the photos?

c[_]

That is a broken part of a plastic kids toy. I think maybe a "telescope." I'll take a closer look for you tonight.

Ben_Edict · 05-27-2008, 12:28 PM

Sometimes it is not only the higher magnification. Some lenses reach their limits obviously, because they don't work good with the sensor geometry (Bayer filter or whatever) One example is my Sigma 24-135 f2,8-4. It worked very good with my old istDS, when I closed the aperture to f8. Totally acceptable in terms of sharpness and contrast.
I rarely use it, so I didn't try it on my K10. But I had one recent occasion, to use it with the K20 and the results are abysmal... Contrast – what contrast? The edge contrast is so low, that people look as whether they got a gloriole around their heads. This is only slightly exaggerated to describe the effect.

Ben

ll_coffee_lP · 05-27-2008, 02:41 PM

Originally posted by PentaxPoke

That is a broken part of a plastic kids toy. I think maybe a "telescope." I'll take a closer look for you tonight.

Sure, sure.

c[_]

PentaxPoke · 05-28-2008, 01:29 PM

Originally posted by ll_coffee_lP

Sure, sure.

c[_]

Ok, it was a broken toy flashlight. I took a picture just in case you didn't believe me.

rburgoss · 05-28-2008, 01:37 PM

Stop looking at the details, start looking at the pictures.

After 35+ years of making pictures, I stopped many years ago trying to get rid of distortions, lack of detail, lack of contrast en so on... I've now learned to look at the picture as a whole.

Does it look good? OK, enough said. If it doesn't look good, then pinpoint the cause, and please, look among everything involved, not only de glass/camera combination. I've learned that most of the time a picture doesn't look good, the cause is far away from the hardware used, and found that light, subject, location, time of day, environment, etc. was to blame for bad results.

Remember, the hardware is the "means" for producing a picture. Good hardware does not guarantee a good picture.... thinking about that, just ask yourselves this question:

Where does the music come from: the piano or the pianist?

ll_coffee_lP · 05-28-2008, 05:53 PM

Piano?!?

c[_]

**Sailor** · 05-28-2008, 06:11 PM

Originally posted by PentaxPoke

Thanks Richard!

Ok, here is the test:

k10d and Pentax 18-250 at 18mm, 50mm, 100mm, 250mm
k20d and Pentax 18-250 at 18mm, 50mm, 100mm, 250mm
k20d and DA* 50-135 50mm, 100mm

Not entirely scientific. Handheld (with 1/500 shutter speed and SR on however). k20d images are 20% "bigger" in dimension at 100% due to increased resolution.

All original files are here:
k10d and k20d DA 18-250 and DA* 50-135 - a set on Flickr

I am showing the crops since that is the only place I think you will see major differences. All were cropped from highest res images viewed at 100%. I think those with a k10d and/or an 18-250 lens will be pleasantly surprised.

Thanks for going to all the work posting these excellent comparisons. Based on your crops, my bleary old eyes don't see much of a IQ difference between the K10 and K20D with the DA 18-250.

Unless I missed it, there's no comparison between the K10D and K20D using the high end DA* lens. Did you make that comparison? If so, please post the crops - that would be invaluable to those of us with K10D's who are still fence sitting vis a vis buying a K20D. If the lens quality of the DA 18-250 is the limiting factor (and unable to exploit the sensor quality of the K20D), we should see a clear difference in the IQ of the two bodies with the DA* lens, since that should make the sensor the limiting factor.

Thanks again,

Jer

PentaxPoke · 05-28-2008, 08:21 PM

Thanks Sailor. I was happy to do it. I agree about your conclusion about the IQ. If I would have been thinking, I would have done the test you suggested. All I had to do was switch the lens on the k10d.

I just remembered...I already did that test! Scroll down to the last couple of posts. I added the k10d pics for comparison. Here is the link:
https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/28149-k20d-pen...-50-135-a.html

NicholasN · 05-28-2008, 09:32 PM

I just purchased a K20D along with a Tamron 28-300mm XR (Film lens). I have found that the shots are not of the same quality that I used to get from my K100D and Sigma 70-300mm DG Macro.

Would I be better of looking at another lens which would give me better quality images? The Tamron gives me 3.5 - 6.3 at 300mm however it just feels "slow".

Any ideas? If anyone could suggest a similar lens to the 28-300 Tamron in a more expensive class i'd be happy to buy it.

Thanks

Nick

PentaxPoke · 05-28-2008, 10:21 PM

Nick,

When you say "slow" do you mean the aperture is not fast enough for your needs, or do you mean that the AF is slow? In this thread the pics showed that you have to go all the way to 100% crop to really see the difference between the DA* and the Pentax 18-250 lens. The 18-250 is great if you have enough light.

**Sailor** · 05-29-2008, 03:53 PM

Originally posted by PentaxPoke

Thanks Sailor. I was happy to do it. I agree about your conclusion about the IQ. If I would have been thinking, I would have done the test you suggested. All I had to do was switch the lens on the k10d.

I just remembered...I already did that test! Scroll down to the last couple of posts. I added the k10d pics for comparison. Here is the link:
https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/28149-k20d-pen...-50-135-a.html

Thanks, PP - this was very helpful. It looks to me as if both cameras perform very well. When I look at the maximally expanded Original sized images, I'd give a slight nod to the K20D in terms of IQ, but the difference is to my eye extremely subtle.

Thanks, once again, for your trouble.

Jer

05-28-2008, 08:21 PM	#26
PentaxPoke Veteran Member Join Date: Jan 2008 Location: Oklahoma Posts: 1,411	Thanks Sailor. I was happy to do it. I agree about your conclusion about the IQ. If I would have been thinking, I would have done the test you suggested. All I had to do was switch the lens on the k10d. I just remembered...I already did that test! Scroll down to the last couple of posts. I added the k10d pics for comparison. Here is the link: https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/28149-k20d-pen...-50-135-a.html Last edited by PentaxPoke; 05-28-2008 at 09:27 PM.

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05-26-2008, 08:30 PM	#16
happicamper New Member Join Date: Feb 2008 Location: SF, CA Posts: 7	I agree, the 18-250 is a very good lens with the right amount light. I bought it as my kit lens with the camera. I had a rough work out at first when only able to get out and shoot in low light mid winter afternoon conditions. I realized that I had quite a learning curve to get to know this lens and camera. Happy to report now that I've had some very nice results with this lens in good lighting. I recently picked up the 50-135 for much the same reason as you and had my first opportunity to really use it last weekend. Sweet lens and very sharp. My current kit is very similar to yours less the K20 and macro. Cindy

05-26-2008, 08:38 PM	#17
PentaxPoke Veteran Member Join Date: Jan 2008 Location: Oklahoma Posts: 1,411	Sounds like we have gone down the same lens buying path...I just ordered the DA* 16-50 and that will be my last lens purchase for a looong time. So much of my shooting is indoors in lower light, hence my insatiable appetite for f2.8 and lower lenses.

05-27-2008, 10:34 AM	#18
ll_coffee_lP Inactive Account Join Date: Jan 2008 Location: Ontario, Canada Posts: 1,972	Great test...and thanks for taking the time to display your results! One quick question though for photos 5-7. Is that a shotgun shell just above the bulldozer in the photos? c[_]

05-27-2008, 12:20 PM	#19
PentaxPoke Veteran Member Join Date: Jan 2008 Location: Oklahoma Posts: 1,411	Originally posted by ll_coffee_lP Great test...and thanks for taking the time to display your results! One quick question though for photos 5-7. Is that a shotgun shell just above the bulldozer in the photos? c[_] That is a broken part of a plastic kids toy. I think maybe a "telescope." I'll take a closer look for you tonight.

05-27-2008, 12:28 PM	#20
Ben_Edict Veteran Member Join Date: Jul 2007 Location: SouthWest "Regio" Photos: Albums Posts: 3,309	Sometimes it is not only the higher magnification. Some lenses reach their limits obviously, because they don't work good with the sensor geometry (Bayer filter or whatever) One example is my Sigma 24-135 f2,8-4. It worked very good with my old istDS, when I closed the aperture to f8. Totally acceptable in terms of sharpness and contrast. I rarely use it, so I didn't try it on my K10. But I had one recent occasion, to use it with the K20 and the results are abysmal... Contrast – what contrast? The edge contrast is so low, that people look as whether they got a gloriole around their heads. This is only slightly exaggerated to describe the effect. Ben

05-27-2008, 02:41 PM	#21
ll_coffee_lP Inactive Account Join Date: Jan 2008 Location: Ontario, Canada Posts: 1,972	Originally posted by PentaxPoke That is a broken part of a plastic kids toy. I think maybe a "telescope." I'll take a closer look for you tonight. Sure, sure. c[_]

05-28-2008, 01:29 PM	#22
PentaxPoke Veteran Member Join Date: Jan 2008 Location: Oklahoma Posts: 1,411	Originally posted by ll_coffee_lP Sure, sure. c[_] Ok, it was a broken toy flashlight. I took a picture just in case you didn't believe me.

05-28-2008, 01:37 PM	#23
rburgoss Veteran Member Join Date: May 2008 Location: San Jose, Costa Rica Photos: Gallery \| Albums Posts: 972	Stop looking at the details, start looking at the pictures. After 35+ years of making pictures, I stopped many years ago trying to get rid of distortions, lack of detail, lack of contrast en so on... I've now learned to look at the picture as a whole. Does it look good? OK, enough said. If it doesn't look good, then pinpoint the cause, and please, look among everything involved, not only de glass/camera combination. I've learned that most of the time a picture doesn't look good, the cause is far away from the hardware used, and found that light, subject, location, time of day, environment, etc. was to blame for bad results. Remember, the hardware is the "means" for producing a picture. Good hardware does not guarantee a good picture.... thinking about that, just ask yourselves this question: Where does the music come from: the piano or the pianist?

05-28-2008, 05:53 PM	#24
ll_coffee_lP Inactive Account Join Date: Jan 2008 Location: Ontario, Canada Posts: 1,972	Piano?!? c[_]

05-28-2008, 06:11 PM	#25
Sailor Loyal Site Supporter Join Date: Nov 2006 Location: Coastal Texas Photos: Gallery Posts: 26,205	Originally posted by PentaxPoke Thanks Richard! Ok, here is the test: k10d and Pentax 18-250 at 18mm, 50mm, 100mm, 250mm k20d and Pentax 18-250 at 18mm, 50mm, 100mm, 250mm k20d and DA* 50-135 50mm, 100mm Not entirely scientific. Handheld (with 1/500 shutter speed and SR on however). k20d images are 20% "bigger" in dimension at 100% due to increased resolution. All original files are here: k10d and k20d DA 18-250 and DA* 50-135 - a set on Flickr I am showing the crops since that is the only place I think you will see major differences. All were cropped from highest res images viewed at 100%. I think those with a k10d and/or an 18-250 lens will be pleasantly surprised. Thanks for going to all the work posting these excellent comparisons. Based on your crops, my bleary old eyes don't see much of a IQ difference between the K10 and K20D with the DA 18-250. Unless I missed it, there's no comparison between the K10D and K20D using the high end DA* lens. Did you make that comparison? If so, please post the crops - that would be invaluable to those of us with K10D's who are still fence sitting vis a vis buying a K20D. If the lens quality of the DA 18-250 is the limiting factor (and unable to exploit the sensor quality of the K20D), we should see a clear difference in the IQ of the two bodies with the DA* lens, since that should make the sensor the limiting factor. Thanks again, Jer

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05-28-2008, 09:32 PM	#27
NicholasN Inactive Account Join Date: May 2008 Location: Sydney, Australia Posts: 301	I just purchased a K20D along with a Tamron 28-300mm XR (Film lens). I have found that the shots are not of the same quality that I used to get from my K100D and Sigma 70-300mm DG Macro. Would I be better of looking at another lens which would give me better quality images? The Tamron gives me 3.5 - 6.3 at 300mm however it just feels "slow". Any ideas? If anyone could suggest a similar lens to the 28-300 Tamron in a more expensive class i'd be happy to buy it. Thanks Nick

05-28-2008, 10:21 PM	#28
PentaxPoke Veteran Member Join Date: Jan 2008 Location: Oklahoma Posts: 1,411	Nick, When you say "slow" do you mean the aperture is not fast enough for your needs, or do you mean that the AF is slow? In this thread the pics showed that you have to go all the way to 100% crop to really see the difference between the DA* and the Pentax 18-250 lens. The 18-250 is great if you have enough light.

05-29-2008, 03:53 PM	#29
Sailor Loyal Site Supporter Join Date: Nov 2006 Location: Coastal Texas Photos: Gallery Posts: 26,205	Originally posted by PentaxPoke Thanks Sailor. I was happy to do it. I agree about your conclusion about the IQ. If I would have been thinking, I would have done the test you suggested. All I had to do was switch the lens on the k10d. I just remembered...I already did that test! Scroll down to the last couple of posts. I added the k10d pics for comparison. Here is the link: https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/28149-k20d-pen...-50-135-a.html Thanks, PP - this was very helpful. It looks to me as if both cameras perform very well. When I look at the maximally expanded Original sized images, I'd give a slight nod to the K20D in terms of IQ, but the difference is to my eye extremely subtle. Thanks, once again, for your trouble. Jer