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01-09-2013, 09:11 PM   #1
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Testing my new DA 300-can it get sharper

HI just testing out my new DA300 and wonder if I need to fine adjust the focus,and if this is how the IQ of this lens should be, or am I doing something wrong?
the 1st 3 are with the Pentax AF1.7TC,and the last 2 just the DA300. Used a heavy monopod with SR on,maybe a mistake?
1st is JPEG,rest are DNG processed with CS5
if I fine adjust the focus can I save the settings for this lens.And best way to fine adjust is?
the white swans are about 100m away or so
Thanks

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01-09-2013, 09:19 PM   #2
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There are too many variables in this setup to come to any solid conclusion.

This is what I do with a new lens to test it and to see what its capabilities are.

Set up on a tripod and choose a static subject that has good contrast in good light.
Do NOT use any teleconverters when testing the lens.
Use the 2 second timer when test shooting to take away any possible vibration.
Shoot at a couple different aperture values to compare.

Once you do that, then take a good look at your images. I think you will find your lens is plenty sharp. With what you posted here, you were using a teleconverter for half the photos, you were on a monopod, and the light looks like it was late in the day and not that bright. Also, only your first image shows the EXIF data which is very important for anyone to give you any opinion or help.
01-09-2013, 09:25 PM   #3
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The first 3 appear a little under-exposed, this could be due to the use of a TC. As for sharpness, about 5.6 seems to be the hotspot for my copy but even at f/4 it is still pretty crispy.

Post some exposure info on the last one - really can't tell from the first three because of them being underexposed, even bringing the exposure up in post will muddy the results, exposure needs to be spot-on during the actual shot [exposure] for the sensor to interpret the light/image/exposure properly...
01-09-2013, 09:43 PM   #4
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the last 2 look better than with the tc, i don't have the lens but I would expect better results

01-10-2013, 03:08 PM   #5
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it was overcast on all the pics, no sun and winter here has little light..
these have the exif,not sure why the others didn't? these are OOC Jpegs just cropped abit,SR was on the 1st,monopod used on all. It seems alot of noise and max iso was only 1600--is that normal
I am trying to find the best settings to shoot birds with the DA300. also BIF ..use on single spot AF ,if that's good enough?
the 2nd one is underexposed I know but it seemed to be sharper..
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01-10-2013, 03:40 PM   #6
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The second one has the highest shutter speed, that may be why it looks a little more sharper. You are shooting these at f/4, f/5~5.6 will resolve better with this lens. As for the noise, 1600ISO with the K5 in daylight produces near zero noise, the reason why the noise is showing is because of 2 things - 1) noise will show quite a bit in underexposed images especially in the dark spots. 2) You are shooting jpeg; in camera noise reduction is only fair at best, shoot in RAW and apply noise reduction in post.

1/500th or higher on the shutter speed when handheld is desirable with this lens unless you are really steady. Also, if you are using on a tri/monopod make sure shake reduction is OFF...
01-10-2013, 03:47 PM   #7
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QuoteOriginally posted by joe.penn Quote
The first 3 appear a little under-exposed, this could be due to the use of a TC. As for sharpness, about 5.6 seems to be the hotspot for my copy but even at f/4 it is still pretty crispy.

Post some exposure info on the last one - really can't tell from the first three because of them being underexposed, even bringing the exposure up in post will muddy the results, exposure needs to be spot-on during the actual shot [exposure] for the sensor to interpret the light/image/exposure properly...
exif on the cat
K5II
shutter 1/100
F6.3
ISO 400
DA300
metering -pattern
01-10-2013, 07:19 PM   #8
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QuoteOriginally posted by joe.penn Quote
The second one has the highest shutter speed, that may be why it looks a little more sharper. You are shooting these at f/4, f/5~5.6 will resolve better with this lens. As for the noise, 1600ISO with the K5 in daylight produces near zero noise, the reason why the noise is showing is because of 2 things - 1) noise will show quite a bit in underexposed images especially in the dark spots. 2) You are shooting jpeg; in camera noise reduction is only fair at best, shoot in RAW and apply noise reduction in post.

1/500th or higher on the shutter speed when handheld is desirable with this lens unless you are really steady. Also, if you are using on a tri/monopod make sure shake reduction is OFF...
yes the 1st one has SR on, from my film days shutter speed = lens length so I guess its the same here..until I get a grip for the K5
even ones in DNG had noise,but only used camera raw 6.5 NR,is there a better one to use? as have not done much NR before..always shot at ISO 100 with my OLY gear

01-10-2013, 08:01 PM   #9
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QuoteOriginally posted by Shanti Quote
from my film days shutter speed = lens length
It's a cropped sensor, should be 1.5 * Focal length = 450 for the 300mm lens.

QuoteOriginally posted by Shanti Quote
even ones in DNG had noise,but only used camera raw 6.5 NR,is there a better one to use?
I use lightroom which does a good job - my in camera settings has all NR turned off, then I pull it in post and do the NR.
01-11-2013, 10:10 PM   #10
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Why so unsharp?? Dud DA300

why are these not focused properly? shutter speed was high,SR on,stopped down..I wonder if this lens is a dud? anyone have to return their DA300 due to focus problems?
these are OOC jpegs and exposure on the swans could be better,but focus should be clearer...
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01-12-2013, 07:50 AM   #11
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Based on my own testing procedures for newly acquired lenses, here's what I would do to test the focus of your DA*300 (assuming the LV/contrast detect and optical/phase detect autofocus on your camera are working correctly).

1. Attach a bank note to a blank white A3 or A2 sheet of paper. Make sure the note is flush with the paper and not bulging away from the paper. Then attach the paper to a wall at eye level in a room that is well lit with natural light.

2. Place the camera on a tripod at the same height perpendicular to the bank note, and at a distance where the bank note fills/lies within the central rectanglar focus frame of the optical viewfinder. Make sure you are outside the lens' minimum focusing distance.

3. Change the drive setting to remote control. Set the AF dial to centre focus. Change the aperture to its widest setting (f/4 in this case). Turn on LV.

4. Focus in LV using the camera's AF (using the shutter release or AF button depending on your settings).

5. In LV & using the remote, take a photo of the bank note.

6. Repeat steps 4 & 5 a couple of times, taking two or three separate images/photos.

7. Examine the resulting images (pixel peep them) on a large screen or in camera. You'll easily be able to see if the images are soft. If they are unsatisfactory and there's nothing wrong with LV and your other AF lenses, then the lens is a dud.

8. If the LV images are satisfactory, then turn off LV and take a few more images at f/4 like before but using "normal" "optical" (phase detect) AF.

9. If the images are not as sharp as the LV ones, then the phase detect AF needs to be adjusted for the lens.

10. To adjust the PDAF do the following,

10a. Stand on a chair so that you can look down directly on the lens' distance scale.
10b. In LV, AF the camera as before and note the alignment of the numbers on the distance scale. You don't have to take an actual shot.
10c. Turn off LV. Turn the lens focus ring so that the lens is unfocused. Then focus using AF. Are the numbers on the distance scale aligned the same as in LV? If they are then your AF does not need adjustment for the lens. If the numbers are not aligned then your AF needs to be adjusted to compensate for either back focus or front focus. Adjust the AF using the camera's AF Fine Adjustment setting, repeating steps 10b and 10c until the numbers on the distance scale are aligned the same in LV (CDAF) and in optical view (PDAF). If you can't get your PDAF adjusted properly yourself or if the adjustments needed are greater than the maximum allowed by the camera then you'll need to get the calibration done by a professional repair shop.

11. Otherwise, if you're sastified with your AF adjustment, take the lens outdoors and shoot with it again.

Hope that helps
Gray
01-12-2013, 09:59 AM   #12
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Note that at iso 1600 there is already some amount of noise reduction that decrease sharpness.
I wonder, if these shots are jpecg out of camera, why the size of the file is so small (example :the swans on third picture, or the cat on last picture, only 159 kBytes). Typically a full jpeg is several mbytes. Or this are 100 % crops ? What are your jpeg settings ?
01-12-2013, 11:52 AM   #13
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My initial test of a new to me lens is to shoot my computer monitor. I open a word document and increase the mag of the page so it covers the screen. The screen is bright enough for the AF to work, and I shoot it handheld, taking a number of shots from slightly differing positions. The text on the screen is irrelevant -- I look to see how well the lens resolves the individual pixels from the screen. If the lens is decentered, I'll see a consistent softness on one side throughout the series. If the lens cannot resolve individual pixels anywhere on the screen, it probably won't work for me, but I'll play with it a bit more to see if it might be a focus problem.

After this, I shoot stuff around the house at base ISO and vary the aperture using the popup flash. The cats are suitable subjects, but after 13 years, know enough to stay away when they see a camera in my hands.
I shoot anything and everything. By shooting bookcases from an angle wide open, I can see if there's a focus problem. The flash takes away technique variables. The shots aren't pretty, but they are effective to show me what I want to know about the lens.

If the lens passes this, then I take it out to shoot in the field to see if there are real life handling problems. In about an hour, I can pretty fully evaluate the lens' usefulness to me. I save all of the shots in a folder with the lens' name so I have a baseline for future reference if I need it.

The indoor tests are easy (and fun if I can find one of those freakin' cats), the field test is just fun, playing with a new toy. If I want to get obsessive, I have a newspaper ironed flat and mounted to a piece of 1/4" plywood stored behind a bookcase. I can hang it, set up the tripod, measure and level things off, ect, and shoot this, but I really hate this type of testing. . .so I don't do it anymore.

Perhaps I'm too casual in my lens testing, but it's worked for me for quite a few years and quite a few lenses, and I don't have any real complaints about the results I'm getting with them.

Scott
01-12-2013, 01:23 PM   #14
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QuoteOriginally posted by goubejp Quote
Note that at iso 1600 there is already some amount of noise reduction that decrease sharpness.
I wonder, if these shots are jpecg out of camera, why the size of the file is so small (example :the swans on third picture, or the cat on last picture, only 159 kBytes). Typically a full jpeg is several mbytes. Or this are 100 % crops ? What are your jpeg settings ?
I resized them as limit here is not so big ca 200x1600,I have the DNG as well but can I upload those here? not much difference though
01-12-2013, 01:33 PM   #15
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QuoteOriginally posted by Gray Quote
Based on my own testing procedures for newly acquired lenses, here's what I would do to test the focus of your DA*300 (assuming the LV/contrast detect and optical/phase detect autofocus on your camera are working correctly).

1. Attach a bank note to a blank white A3 or A2 sheet of paper. Make sure the note is flush with the paper and not bulging away from the paper. Then attach the paper to a wall at eye level in a room that is well lit with natural light.

2. Place the camera on a tripod at the same height perpendicular to the bank note, and at a distance where the bank note fills/lies within the central rectanglar focus frame of the optical viewfinder. Make sure you are outside the lens' minimum focusing distance.

3. Change the drive setting to remote control. Set the AF dial to centre focus. Change the aperture to its widest setting (f/4 in this case). Turn on LV.

4. Focus in LV using the camera's AF (using the shutter release or AF button depending on your settings).

5. In LV & using the remote, take a photo of the bank note.

6. Repeat steps 4 & 5 a couple of times, taking two or three separate images/photos.

7. Examine the resulting images (pixel peep them) on a large screen or in camera. You'll easily be able to see if the images are soft. If they are unsatisfactory and there's nothing wrong with LV and your other AF lenses, then the lens is a dud.

8. If the LV images are satisfactory, then turn off LV and take a few more images at f/4 like before but using "normal" "optical" (phase detect) AF.

9. If the images are not as sharp as the LV ones, then the phase detect AF needs to be adjusted for the lens.

10. To adjust the PDAF do the following,

10a. Stand on a chair so that you can look down directly on the lens' distance scale.
10b. In LV, AF the camera as before and note the alignment of the numbers on the distance scale. You don't have to take an actual shot.
10c. Turn off LV. Turn the lens focus ring so that the lens is unfocused. Then focus using AF. Are the numbers on the distance scale aligned the same as in LV? If they are then your AF does not need adjustment for the lens. If the numbers are not aligned then your AF needs to be adjusted to compensate for either back focus or front focus. Adjust the AF using the camera's AF Fine Adjustment setting, repeating steps 10b and 10c until the numbers on the distance scale are aligned the same in LV (CDAF) and in optical view (PDAF). If you can't get your PDAF adjusted properly yourself or if the adjustments needed are greater than the maximum allowed by the camera then you'll need to get the calibration done by a professional repair shop.

11. Otherwise, if you're sastified with your AF adjustment, take the lens outdoors and shoot with it again.

Hope that helps
Gray
Hi Gray will try that,just did a test of a still life at F4, 5.6 ,6.3 iso 100 using ass the AF adjustments + & - ,>AF pattern & AF spot--- still think something is not right
this is the dng to jpeg straight conversion of one with = AF adjustment...the lens was not sealed in the box when it came? camera is 1 week old, the kit lens seems sharp as can be for a kit lens..I wonder if there are duds of the DA300 as its so $$ ,and I know here in Denmark they don't sell many
funny no exif on this one?? ISO 100 ,F6.3, 1sec AF pattern
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