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10-29-2014, 08:31 AM   #16
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QuoteOriginally posted by luftfluss Quote
Diffraction is generally more lens-dependent than sensor-dependent. For example, on FF, the Canon 85/1.2 is already showing (marginal) effects of diffraction at f/5.6. With most lenses, once you are more than 2 stops down, center sharpness begins a slow decline. Of course, once you are stopped waaay down, you get the worst of both worlds.
True, but don't have the means to measure how light is curved by specific aperture blades in specific optical designs, so I'm left with measurb... a-hem! mathematical calculations!

QuoteOriginally posted by luftfluss Quote
WRT "absolute maximum picture quality and sharpness" at f/8 on the K-3, well, that depends. f/8 on many lenses leads to a slight decline in center sharpness but an increase in edge sharpness due to the increased DoF compensating for field curvature.
Still talking about the AMC-M 50mm f/1.7, the only lens I made meaningful tests with (the rest of the time I'd rather take pictures ), edge sharpness was better at f/5.6 than at f/8 on APS-C. Can't test edge sharpness on FF ATM...

QuoteOriginally posted by nicoprod Quote
My personal non scientific experience is that fast lenses have their sharpest rendering at 5.6 and kit lenses performed better at f9.
That's probably because at f/5.6 diffraction is less a factor than poor "wide open" rendition, while fast lenses are more than 3 stops closed at f/5.6...

10-29-2014, 08:48 AM   #17
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QuoteOriginally posted by LensBeginner Quote
Still talking about the AMC-M 50mm f/1.7, the only lens I made meaningful tests with (the rest of the time I'd rather take pictures ), edge sharpness was better at f/5.6 than at f/8 on APS-C. Can't test edge sharpness on FF ATM...
That could be, because a fast lens like the 50/1.7 is already 3.5 stops down at f/5.6.

I agree with rather taking pics... I seldom worry about things like diffraction.
10-29-2014, 09:04 AM   #18
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QuoteOriginally posted by LensBeginner Quote
The 100% crop is full quality, as stated. The other was just to give you a feel for how close/far to the corners/center was the flower, and there's a 1MB limit on images for me.
I was referring to the first image, though the exif for both indicates that compression was used. The reason why I thought the focus was behind the flower was because the leaves visible in the top image below the flower appear to be the point of focus.

Beyond focus point, this image is somewhat of a puzzle. I am very familiar with the 18-55 kit and its performance characteristics. It is soft at the long end, but this sort of "glow" is atypical and is more of what I might expect from a cheap vintage zoom with an overdose of fungus. Assuming that you did not have a filter mounted, there may very well be a problem with your lens.

In regards to the upload limits, you might want to consider hosting your images at Flickr or a similar site and linking the original there to your posts here. Flickr will even provide the BB code snippets for you to paste into your post.


Steve

---------- Post added 10-29-14 at 09:07 AM ----------

QuoteOriginally posted by luftfluss Quote
I seldom worry about things like diffraction.
Good idea.


Steve
10-29-2014, 09:18 AM   #19
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I just got my 18-55 WR lens. I was rather expecting lackluster results, since it is a kit lens, and many feel it's not good. So far, I find it a great lens. The first image was taken about a foot away at 35mm. The second image was at 55mm, again about a foot away. Absolutely no pp, straight out of the camera.

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10-29-2014, 11:36 AM   #20
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Yep, did test shots, softness is a f/5.6 thing (duh!).
And @nicoprod is absolutely right: f/9 beats f/8 hands down...
I also tried a series of shots at 35mm, and f/5.6 is a tad better than wide open (f/4.5).
10-29-2014, 01:09 PM   #21
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Just Mentioning Settings

QuoteOriginally posted by LensBeginner Quote
I got a flea in one ear about it in another thread, so I'm asking here...
18-55 WR on a K-01, bad picture quality at close range, is my lens a dud or is this normal performance?

Downscaled image (16->6MP), for scale & position of the detail in the frame:


A 100% crop, maximum quality jpeg:


I don't believe that halo should be there (top left) at all, not at f/5.6.
Maybe it's just the "macro" (read "marketing") focusing range that's to blame?
Thanks in advance

You may already basically know this, but I have just a couple things I wanted to mention. I myself have taken shots of flowers with the 18-55 and have usually had nice results with it. I am not sure how you have your camera set, but I have used the following setting(s): I have the AF point switch on the back of my camera to the setting choice with the dot in the center of the rectangle (uppermost one) for focusing the subject in the center and for continuous focus I set the focus mode to "C" on the camera. Other than that, these are suggestions I have used successfully with the ALII version of the lens in case you are interested: I have used TAV mode using several F Stop settings (usually between F8 and F18) and shutter speed settings (usually between 125 and 250) and I usually get very reasonable sharpness. Depending sometimes on the situation if I need a specific area of a subject to be in focus I may use manual focus. I like the depth of field that is why I use F stop settings I mentioned. I am not sure if you want to use it since you are already using a shutter speed of 500, and may not need it at lower shutter speeds, but if you have SR (shake reduction) on your camera you may want to enable it if you feel it may help.
Good luck.

Last edited by C_Jones; 10-29-2014 at 01:14 PM. Reason: typo correction
10-29-2014, 02:08 PM   #22
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QuoteOriginally posted by C_Jones Quote
You may already basically know this, but I have just a couple things I wanted to mention. I myself have taken shots of flowers with the 18-55 and have usually had nice results with it. I am not sure how you have your camera set, but I have used the following setting(s): I have the AF point switch on the back of my camera to the setting choice with the dot in the center of the rectangle (uppermost one) for focusing the subject in the center and for continuous focus I set the focus mode to "C" on the camera. Other than that, these are suggestions I have used successfully with the ALII version of the lens in case you are interested: I have used TAV mode using several F Stop settings (usually between F8 and F18) and shutter speed settings (usually between 125 and 250) and I usually get very reasonable sharpness. Depending sometimes on the situation if I need a specific area of a subject to be in focus I may use manual focus. I like the depth of field that is why I use F stop settings I mentioned. I am not sure if you want to use it since you are already using a shutter speed of 500, and may not need it at lower shutter speeds, but if you have SR (shake reduction) on your camera you may want to enable it if you feel it may help.
Good luck.
I took a lot of flower pictures and I think many of them are ok, if I may say so myself.
I was doing a trekking and just taking a snapshot with that kit lens and the quality was not the minimum I expected, that's why I asked.
This is a more "serious" one, sorry for low quality and watermark, I'm a little paranoid when it comes to posting pics.


Specs are SMC-M 50mm f/1.7 at f/11 with 2x Kenko macro TC (thus 100mm & f/22), off camera flash triggered by pop-up covered by DIY IR filter.
Magnification is about 1:1.2, both camera and flash are handheld.

Thanks for your help though, I will look into your settings & try them with the 18-55.

Last edited by LensBeginner; 10-29-2014 at 02:25 PM.
10-31-2014, 09:53 AM   #23
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QuoteOriginally posted by LensBeginner Quote
I took a lot of flower pictures and I think many of them are ok, if I may say so myself.
I was doing a trekking and just taking a snapshot with that kit lens and the quality was not the minimum I expected, that's why I asked.
This is a more "serious" one, sorry for low quality and watermark, I'm a little paranoid when it comes to posting pics.


Specs are SMC-M 50mm f/1.7 at f/11 with 2x Kenko macro TC (thus 100mm & f/22), off camera flash triggered by pop-up covered by DIY IR filter.
Magnification is about 1:1.2, both camera and flash are handheld.

Thanks for your help though, I will look into your settings & try them with the 18-55.
I myself do not use teleconverters, so I don't want to try to evaluate them, and do not do a lot of macro activities (though I have done some), but it looks like you are getting some positive results. I am not sure what shutter speed you are using, but it is obvious you are achieving detail without it being blurred by too much camera or subject movement. With real experience as what you are doing you will probably discover the varieties of settings that are effective for the the results you need most of time. It looks like you are getting good depth and the lighting looks good, along with some sharp detail of the subject. That is a good example of a more centered subject than the first image you had posted. Basically it looks like you have the right idea in the way of utilizing your equipment. Autofocus will probably enable you to get a nice shot most of the time, and if you see something that the AF is not giving you as far as detail, you have the alternative to try manual focus to see if it may or may not help. Good luck, and have a good day.

10-31-2014, 10:51 AM   #24
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QuoteOriginally posted by stevebrot Quote
I am very familiar with the 18-55 kit and its performance characteristics. It is soft at the long end, but this sort of "glow" is atypical and is more of what I might expect from a cheap vintage zoom with an overdose of fungus.
I concur - I've been using a couple copies of the old version 1 kit lens for years, and never encountered that "glow" when shooting wide-open.
10-31-2014, 10:57 AM   #25
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Yep, have the lens as well and is normal in those lighting conditions... you can't expect much from a lens that you can pick up for $40-$60 used.
10-31-2014, 11:48 AM   #26
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QuoteOriginally posted by C_Jones Quote
I myself do not use teleconverters, so I don't want to try to evaluate them, and do not do a lot of macro activities (though I have done some), but it looks like you are getting some positive results. I am not sure what shutter speed you are using, but it is obvious you are achieving detail without it being blurred by too much camera or subject movement. With real experience as what you are doing you will probably discover the varieties of settings that are effective for the the results you need most of time. It looks like you are getting good depth and the lighting looks good, along with some sharp detail of the subject. That is a good example of a more centered subject than the first image you had posted. Basically it looks like you have the right idea in the way of utilizing your equipment. Autofocus will probably enable you to get a nice shot most of the time, and if you see something that the AF is not giving you as far as detail, you have the alternative to try manual focus to see if it may or may not help. Good luck, and have a good day.
That one was a no-brainer: 15E used on a market stall... 7 elements... so it's not the sh****est out there... also works as a "regular" TC & tried some moon shoots with 200mm+TC (600mm equivalent )
IQ takes a huge toll though... a bit of PP needed, mainly because it's very soft... and then those f/11 and f/16 become f/22 or f/32 and all of a sudden the dust on the sensor becomes razor sharp!
still it's not bad on a 6MP sensor... must find the courage to try it on the K-01, but I fear I won't like what I'll see...

Shutter can't recall, must have been 1/125 or 1/180, at any rate close to flash sync.
Flash is also responsible for lack of blur....

I tried again the 18-55 today, will probably post something after PP... mixed bag, really, but got a good 15" or 20" (can't recall, shot 4 or 5 pics) tripod shot @ f/9 in waning light, "macro" range... so it's really about getting used to it, and you shoot it in a very different way from the primes... still, for getting good results on the K-01 I found out that manual focus is a must... can't rely much on CDAF... it becomes a hit-and-miss affair especially in direct light...

Oh, and have a good day you too (I just had... went shooting!), and thanks for the tips!

Last edited by LensBeginner; 10-31-2014 at 12:39 PM.
10-31-2014, 11:58 AM   #27
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QuoteOriginally posted by LensBeginner Quote
T... still, for getting good results on the K-01 I found out that manual focus is a must... can't rely much on CDAF... it becomes a hit-and-miss affair especially in direct light...
I have found the same to be true as well. As a matter of fact, I only use manual lenses on the k-01... or in manual mode.
11-03-2014, 02:49 AM - 1 Like   #28
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QuoteOriginally posted by LensBeginner Quote
I took a lot of flower pictures and I think many of them are ok, if I may say so myself.
I was doing a trekking and just taking a snapshot with that kit lens and the quality was not the minimum I expected, that's why I asked.
This is a more "serious" one, sorry for low quality and watermark, I'm a little paranoid when it comes to posting pics.


Specs are SMC-M 50mm f/1.7 at f/11 with 2x Kenko macro TC (thus 100mm & f/22), off camera flash triggered by pop-up covered by DIY IR filter.
Magnification is about 1:1.2, both camera and flash are handheld.

Thanks for your help though, I will look into your settings & try them with the 18-55.
Very nice shot! (That is one of my favourite lenses)
11-03-2014, 03:03 AM   #29
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QuoteOriginally posted by MarkJerling Quote
Very nice shot! (That is one of my favourite lenses)
Thanks!
As you can tell, it's the same rose as the other shot, just closer (haven't you told me about cropping? )
11-03-2014, 12:28 PM   #30
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QuoteOriginally posted by LensBeginner Quote
Thanks!
As you can tell, it's the same rose as the other shot, just closer (haven't you told me about cropping? )
Indeed! Yes, crop away, but not that much!
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