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06-27-2017, 06:52 PM   #13531
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QuoteOriginally posted by following.eric Quote
I bought a lens calibration card a while back and ran some tests and it seems to be accurate give or take.
Note that calibration results can depend on subject distance. If you calibrated the lens, say near its minimum focus distance, it may not accurately focus on a subject 20m away.

That's why the Sigma dock supports different AF adjustment values depending on (rough) subject distance.

Independently of that, the lens will always be sharper at f/11 compared to f/5.8 at 300mm. For anything at 200mm or below, f/8 is the best choice with respect to sharpness.

06-27-2017, 07:44 PM   #13532
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QuoteOriginally posted by Class A Quote
Note that calibration results can depend on subject distance. If you calibrated the lens, say near its minimum focus distance, it may not accurately focus on a subject 20m away.

That's why the Sigma dock supports different AF adjustment values depending on (rough) subject distance.

Independently of that, the lens will always be sharper at f/11 compared to f/5.8 at 300mm. For anything at 200mm or below, f/8 is the best choice with respect to sharpness.
In the end I didn't calibrate the lens. I followed all the rules for testing and calibration but I didn't adjust the AF because at 50mm,100,200 and 300mm the AF system somestime shot +1 or -2 at different focal lengths. At 300mm it seems accurate so I left it. and Since I usually only put it on the camera for the 300mm range and find it sharper at f13 I just shoot there.

I thought maybe at 300mm with f5.6 the dof would be tough, but I always thought that wildlife cameras are f2.8 or f4 usually so wide open apertures with fast shutter speeds and figured mine would be the same.

But at f5.6 at 300mm it's not sharp, even if focused using a tripod on a still object, Unless that's normal for a lens? I just thought I could still get sharp focus at f5.6 but shallow dof.

at f5.6 I thought I could lets say get the eye sharp and then have a quick drop off for the depth of field at 300mm and if I want more in focus to go f11 for instance. But doesnt seem to work like that on this particular lens but have no other lens similar in focal length to test. i would need to borrow the same lens and test. I might go once I get to the U.K and test on the newer PLM WR version at f5.6 and see if theres a difference.
06-27-2017, 07:56 PM   #13533
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QuoteOriginally posted by following.eric Quote
At f5.6 I thought I could lets say get the eye sharp and then have a quick drop off for the depth of field at 300mm and if I want more in focus to go f11 for instance.
Well, ideally that would be the case.

However, the 55-300 is not a premium lens and at 300mm it does not have stellar performance wide open. Even though f/5.8 may seem "slow" compared to f/2.8, say, you'll see the worst behaviour of the 55-300 at f/5.8 and 300mm (as there is no "stopping down" to help it with aberrations that are worst when a lens is used wide open).

Possibly you have a subpar copy but all copies will perform significantly better at f/11 compared to f/5.8 at 300mm.

You'll notice whether you need calibration at your preferred subject distance if there are areas that are sharper in front or behind the plane you set the focus on. However, I'm assuming you are just not satisfied with the overall level of sharpness at f/5.8.
06-28-2017, 01:39 PM   #13534
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QuoteOriginally posted by Class A Quote
Well, ideally that would be the case.

However, the 55-300 is not a premium lens and at 300mm it does not have stellar performance wide open. Even though f/5.8 may seem "slow" compared to f/2.8, say, you'll see the worst behaviour of the 55-300 at f/5.8 and 300mm (as there is no "stopping down" to help it with aberrations that are worst when a lens is used wide open).

Possibly you have a subpar copy but all copies will perform significantly better at f/11 compared to f/5.8 at 300mm.

You'll notice whether you need calibration at your preferred subject distance if there are areas that are sharper in front or behind the plane you set the focus on. However, I'm assuming you are just not satisfied with the overall level of sharpness at f/5.8.
Ya I would safe the latter, just not satisfied with the sharpness at f5.8. Once you guys told me to shoot around f11 and when light is good I am happy with the quality. But it the subject is in the shade like a hummingbird and I am shooting at f11 I just have to blow the iso up and lose some detail. I think for the price it's honestly not a bad lens. I just thought that maybe maybe copy was bad and that I should be able to shoot closer to f5.8

But let's say I owned a premium 400mm lens at f2.8 (hypothetical lens) Would you be able to even shoot at f2.8 or would it also not work because of the DOF? Or do premiom 1900 dollar lens just function different as whole?

06-28-2017, 01:54 PM - 1 Like   #13535
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QuoteOriginally posted by following.eric Quote
Ya I would safe the latter, just not satisfied with the sharpness at f5.8. Once you guys told me to shoot around f11 and when light is good I am happy with the quality. But it the subject is in the shade like a hummingbird and I am shooting at f11 I just have to blow the iso up and lose some detail. I think for the price it's honestly not a bad lens. I just thought that maybe maybe copy was bad and that I should be able to shoot closer to f5.8

But let's say I owned a premium 400mm lens at f2.8 (hypothetical lens) Would you be able to even shoot at f2.8 or would it also not work because of the DOF? Or do premiom 1900 dollar lens just function different as whole?
Those big 400mm f2.8s are fantastic if you need to shoot in low light, the downside is they are HEAVY! The Canon 400mm f2.8 weighs just under 4kg! and the price, add another 0 to the 1900! The big thing with prime lenses is they are designed to do one focal length well, and there is not a lot of compromise for other focal lengths in the design. The DOF on a 400mm f2.8 lens is pretty shallow, but that also makes it fantastic if you are trying to isolate a subject like a bird or sportsman on a field and don't want the background distracting from the subject.
06-28-2017, 07:31 PM   #13536
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QuoteOriginally posted by following.eric Quote
Would you be able to even shoot at f2.8 or would it also not work because of the DOF?
Whether the DOF will be sufficient will depend on the subject (flatish or deep) and the focusing distance.
Use an online DOF calculator and you'll see that with a 400mm lens at f/2.8 you already have 15-16cm DOF on a subject that is 15m away (on an APS-C Pentax). That should suffice in many cases, right?

The closer the subject, the more problematic will the f/2.8 be in terms of DOF.

QuoteOriginally posted by following.eric Quote
Or do premium 1900 dollar lens just function different as whole?
No, not really.

You can just expect much better performance wide open and peak sharpness around f/4 (rather than f/8).
06-29-2017, 01:53 AM   #13537
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QuoteOriginally posted by Class A Quote
Whether the DOF will be sufficient will depend on the subject (flatish or deep) and the focusing distance.
Use an online DOF calculator and you'll see that with a 400mm lens at f/2.8 you already have 15-16cm DOF on a subject that is 15m away (on an APS-C Pentax).
Exactly what I was thinking. DOF at the distances a 300mm will be used are substantial. Certainly no animal is going to be partly out of focus.

06-29-2017, 08:51 AM   #13538
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QuoteOriginally posted by Class A Quote
Whether the DOF will be sufficient will depend on the subject (flatish or deep) and the focusing distance.
Use an online DOF calculator and you'll see that with a 400mm lens at f/2.8 you already have 15-16cm DOF on a subject that is 15m away (on an APS-C Pentax). That should suffice in many cases, right?

The closer the subject, the more problematic will the f/2.8 be in terms of DOF.


No, not really.

You can just expect much better performance wide open and peak sharpness around f/4 (rather than f/8).
Primarily my problem is higher iso because of light while shooting at f13 in low light. I have some amazing hummingbird shots I got two weeks ago because the late aftersoon sun was sitting right on the feeder. Following day the feeder was in the shade of a tree and even at iso 3200, f13 and trying to slow my shutter speed down a bit bit not too much for a fast moving hummingbird proved tough. DOF at 2.5m distance 300mm focal length at f13 is only 0.03m, Not very much space to place with.

I suppose I could shoot with less focal length to get mor ein focus and then crop in.

There is no way im carrying around a 4kg lens any time soon for my amateur photography. I guess even at f5.8 and a bird 2.5 meters my DOF would be 0.01m anyways. not much room for error.

Cheers guys for all the good information, love finding out new stuff about photography all the time
06-29-2017, 12:00 PM - 1 Like   #13539
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QuoteOriginally posted by following.eric Quote
DOF at 2.5m distance 300mm focal length at f13 is only 0.03m, Not very much space to place with.
Crikey! There aren't many birds in these parts that will let me get within 2.5m.
06-29-2017, 02:16 PM - 2 Likes   #13540
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QuoteOriginally posted by zkarj Quote
Crikey! There aren't many birds in these parts that will let me get within 2.5m.
Not unless you buy them a beer!
06-30-2017, 01:54 AM - 1 Like   #13541
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Kit Lens and a foggy night.

Quite a bit of fog coming down already and after walking the dog, I thought about trying for a night time street scene. I had to settle on single point focus to get the 18-55mm kit lens to focus on anything but it was fun having a play. The lens was Eric's till a few months ago.

The house pic and the car have been cropped a bit to cut out the glare of the street lights but otherwise are jpeg's straight out of the camera.
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Last edited by awa355; 06-30-2017 at 09:22 AM.
07-01-2017, 11:22 AM - 2 Likes   #13542
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Here's a shot of the hummingbird I got. this was shot from less than three meters. Since it came to the feeder it was just a waiting game. Like everything it's a learning curve. first thought was focusing on the feeder but DOF issues didn't allow for that. I settle on Tav mode with iso I think as high as 3200 for some of the shots. Shutter speed up above 1/1000th, F13. I eventually went to single point focus with Continuous AFS, Back button focus so I could control it. Problem with the 300mm is if I missed the bird I would lose the lens to focus hunting as it search for the trees behind the bird, so used light focus burst I guess in combination with firing the shutter.

One thing I have noticed, even shooting in JPEG is the buffer and card writing time. If I fire off 5 to 7 consecutive shots it will lock up the whole camera, I can see the light going crazy as it processes them and tries to write them to the card, sometimes it gets so bad the camera freezes and I have to power it off. Not sure why this is happening.

k50 Jpeg High Burst rate with a 30mb/s SD card never gave me any problem
k70 Jpeg/or Raw high burst rate with 80mb/s SD card almost locks up the camera and sometimes freezes it. Is 80mb/s even for Jpeg on the k70 too slow?

A feature I read that sounds like it would be amazing for birds especially if you are afraid to lose them to focus hunting with a controlled environment like a feeder is the Sigma focus distance you can manually set to close and far limits to keep your lens close to where it needs to be. Must be nice feature if you have the money for the lens.

Anyways here's the shot I like, it will link you to the Flickr folder with some other Canadian animal life I got at the Cottage. the ducks were shot from shore at pretty close distances, They were pretty friendly and I just wait for one male to chase another male away and would grab them in flight. Enjoy

Canada 2017 | Flickr FLICKR ALBUM

[IMG][/IMG]
07-01-2017, 11:27 PM - 1 Like   #13543
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Jeeze Eric you certainly have persevered with the 55 to 300
as far as I remember mine isn't bad at 5.6
it was looking at the sharpness figures at imaging resource
that led me to the f11 conclusion
as far as premium lenses wide open... they are fantastic presumably .
my F* 300/4.5 is perfect wide open

a perfect duck

Last edited by Transit; 07-02-2017 at 02:06 AM.
07-02-2017, 12:02 AM   #13544
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QuoteOriginally posted by following.eric Quote
Here's a shot of the hummingbird I got. this was shot from less than three meters. Since it came to the feeder it was just a waiting game. Like everything it's a learning curve. first thought was focusing on the feeder but DOF issues didn't allow for that. I settle on Tav mode with iso I think as high as 3200 for some of the shots. Shutter speed up above 1/1000th, F13. I eventually went to single point focus with Continuous AFS, Back button focus so I could control it. Problem with the 300mm is if I missed the bird I would lose the lens to focus hunting as it search for the trees behind the bird, so used light focus burst I guess in combination with firing the shutter.
Last year in New Mexico I tried to get images of hummingbirds at a feeder with my K-3 and 55-300. I was by necessity a little further away. I gave up in the end - they are slippery little suckers and I didn't have the time or patience to wait.

I ended up thinking if I was living in North America and wanting to regularly get images of such things then some massively better glass would be in order

So well done on what you got...
07-02-2017, 12:03 AM   #13545
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QuoteOriginally posted by following.eric Quote
Here's a shot of the hummingbird I got. this was shot from less than three meters. Since it came to the feeder it was just a waiting game. Like everything it's a learning curve. first thought was focusing on the feeder but DOF issues didn't allow for that. I settle on Tav mode with iso I think as high as 3200 for some of the shots. Shutter speed up above 1/1000th, F13. I eventually went to single point focus with Continuous AFS, Back button focus so I could control it. Problem with the 300mm is if I missed the bird I would lose the lens to focus hunting as it search for the trees behind the bird, so used light focus burst I guess in combination with firing the shutter.
Last year in New Mexico I tried to get images of hummingbirds at a feeder with my K-3 and 55-300. I was by necessity a little further away. I gave up in the end - they are slippery little suckers and I didn't have the time or patience to wait.

I ended up thinking if I was living in North America and wanting to regularly get images of such things then some massively better glass would be in order

So well done on what you got...
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