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11-22-2012, 05:22 PM   #16
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I haven't bought any new lenses. There are options, such as the DA*300, Sigma has a 300 2.8 with tc's, the 500 4.5. There are two Bigma versions. The price for the 300 f4 is competitive with others. The challenge is finding stuff for $500 to $1000 or so.

11-22-2012, 06:04 PM   #17
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Another option.

I wonder if any of you guys ever tried digiscoping? I used to do that a few years ago with mixed results. I had an old Nikon Coolpix 990 behind a telescope with an eyepiece. It could give you up to a 10000mm equivalent lens but focusing it was a real hassle and image quality sucked most of the time. I stopped doing that when I sold the NIkon because most cameras simply can't hack it. With the Nikon, you used a special eyepiece that simply screwed on the lens where a 28mm filter was normally used so the camera was held by the telescope eyepiece. The picture below is about the only one that I kept as a souvenir. It was taken with the Nikon 990 through an astronomical telescope with eyepiece. The focal length of the scope was about 1500 multiplied by the eyepiece factor. The duck was in the river about 300 feet from where I was. A friend of mine has kept his Nikon 990 and is still doing that kind of stuff with a small Bausch & Lomb telescope. Look at the picture EXIF for details. Thanks for your interesting experiences Derek.

Last edited by VE2CJW; 12-10-2012 at 01:07 PM.
11-22-2012, 06:33 PM   #18
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QuoteOriginally posted by VE2CJW Quote
Derek, you have clearly described my problem. Most of my experiments were done near sunset or on an overcast day with the geese quite far away on the water, good recipe for disaster. Since I have only 300mm to shoot, I had to crop and the result was worse. Looking at your pictures with the 170-500, I can't say that I'm impressed since they look a lot like most of my cropped pictures. I don't think I'll go with a long zoom but will probably explore longer older primes. Thanks for the clear explanations. I'm including a picture taken with my 55-300 that was cropped to get the effect of 600mm. It's not too bad but I need to get closer but there is a limit to cropping. Take care.
Mike.
Mike it is not easy to tell with web based photos but to me the foreground in the cropped geese shot looks sharper than the birds.
Accurate focus will make a huge difference to a cropped image. If you haven't already, check the focus adjustment/calibration with the lens. With long lenses I also recheck calibration with a target set at the distance I most shoot at, especially close to infinity.

Further improvements in image quality can then be gained through, best aperture for resolution/lens, movement/shutter speed, lower iso = better sensor signal to noise & dynamic range, accurate exposure for no blown highlights or excessive shadow noise. All these things are amplified with a heavy crop and make a huge difference to the final image.
Once again looking at the geese shot, the exif shows 300mm 1/400 f8.0 400iso and I believe taken on a tripod. For example it may be possible to lower the shutter speed, you are stabilized from shake and distant subjects don't show as much movement, 1/200 would gain a stop to then reduce to 200iso.

I believe that most lenses when shot at their ideal parameters will yield good results, the only problem being a very narrow window for those parameters. Looking at the Sigma 135-400 @ 400mm f11 would be similar to your 300mm f8 resolution wise. So you will gain some length but only if the light is better will the quality be close to equal. On the other hand a quality prime like the DA300 has a fairly equal resolution from f4 - f11 and @ f4 should beat the peak f8 of your 55-300, all with an extra 2 stops up your sleeve.

In this instance, the 300/4 gives the best performance/weight ratio and an older 400/5.6 or 400/4 perf/price. For everything else (500/4.5 600/4 500/5.6 etc) there's mastercard.

Cheers, Dré.
11-22-2012, 06:59 PM   #19
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Another example.

Since the geese were so far away, I focused where I could and it fell on the wrong plane. I always shoot at f8 on a tripod with 2 seconds delayed shutter release and try to lower the iso. Next time, I'll lower the iso more. My big problem is that the geese are too far, so I can't focus properly, that's why I need a longer lens. Unfortunately, there is no way to get closer because this is in a bird sanctuary. I have checked the focusing of my lens and think it's OK. When shooting nearer subjects, the focus is generally right on. I always use the center dot for focusing. Here is an example of a picture at 300mm that was auto-focused.


Last edited by VE2CJW; 12-10-2012 at 01:07 PM.
11-22-2012, 07:28 PM   #20
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I have lenses that behave differently at infinity, so i would definately recommend finding a suitable distant target (communications tower etc) and checking AF @ f5.8 (several times reset to min focus) against your best manual focus on magnified live view. Take notes and also have a look on your monitor to compare. I have sometimes found suprising results and a better understanding of individual lens behavior.
11-22-2012, 07:34 PM   #21
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I only check focus accuracy at slightly beyond minimum focus distance and minimum aperture. DOF at minimum focus is super thin. If it's good there, it will be good everywhere.
11-22-2012, 09:35 PM   #22
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I start there too Dan with the focus charts, but it doesn't fit for all prime lenses. With zooms it can vary from min to max focal length.
11-22-2012, 09:46 PM   #23
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QuoteOriginally posted by DreTAX Quote
I start there too Dan with the focus charts, but it doesn't fit for all prime lenses. With zooms it can vary from min to max focal length.
I test all my lenses. I've never seen a lens behave like this, although I only have Pentax lenses and I've heard weird stories about the Tamron 17-50. Canon's instructions only recommend one set distance for AF adjust and wide open aperture.
http://www.learn.usa.canon.com/app/pdfs/quickguides/CDLC_Accurate_EOS_AF_QuickGuide.pdf

11-22-2012, 11:46 PM - 1 Like   #24
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QuoteOriginally posted by VE2CJW Quote
Like I mentioned in another thread, I'm using my 55-300 DA L for occasional birding with my K30 and a tripod. The problem is that I haven't got enough range. I am on a tripod and the geese are stationary in the water at about 300 feet. Now, would a Sigma 170-500 lens be as sharp at 500mm as my 55-300 at 300mm? Would the Sigma 120-400 be as sharp at 400? If I decided to use a 1.4X TC with my 55-300, can you suggest a good one that would work fine with that lens and my K30? I could also go the prime way and got some good ideas in the other thread but can't spend too much, so I'll forget about the Pentax ED monsters. Thanks for your ideas and your experience. Sorry about starting another thread but the other one was not clear enough about what I wanted to know. That's what happens whan a Frenchie from Quebec tries to express himself in English.
Mike.
You need to learn a little math.
Image size = subject sizes x focal length / distance

Even with a 500 mm lens the good at 300 feet will only occupy an area of abut 2.5mm square on your 24 x 16 sensor. It is just not close enough for a quality , frame filling shot.

Get closer...... And save your money
11-23-2012, 06:29 AM   #25
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QuoteOriginally posted by Miguel Quote
While the Q really intrigues me as a street or fun art shooting tool, I cannot fathom using it for high-quality capture of moving objects like birds. Both the shutter lag and being required to use the LCD rear viewfinder I would find way too frustrating. Image quality further compounds things.
BIF is not what I had in mind. I'm thinking of a particular scenario that defeats me so far. I don't need a telephoto lens to shoot Mallards. Black ducks, geese and swans, I can shoot them with a kit lens. There are interesting duck species around here, but they are rightfully terrified of humans. They fly off immediately if anyone approaches. They're easy to view at a distance, they swim around in the middle of a bay or lake, far from shore. I could use a Q with my DA*300 on tripod for an equivalent FOV of about 1650mm to shoot these ducks. But then like I said, the IQ is not very satisfying.
11-23-2012, 06:52 AM   #26
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I love to do the math, that's not a problem. I simulate lenses in Photoshop to see the effect. The reason why I want a longer lens is to get the subject a little closer so I can focus easily. I also want a sharper lens so I can crop more. I have been doing tests with my 55-300 and can crop to 1200mm on a well focused subject but that doesn't work well on farther subjects. The geese I want to shoot are too far away and I can't get closer unless using a boat in the St Lawrence river rapids. Like audiobomber said, if you CAN get closer, the birds fly away which is a beautiful sight when there are hundreds of birds.
11-23-2012, 12:30 PM   #27
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QuoteOriginally posted by audiobomber Quote
There are interesting duck species around here, but they are rightfully terrified of humans.
QuoteOriginally posted by VE2CJW Quote
The geese I want to shoot are too far away and I can't get closer
These kinds of problems are solved less by spending much money on equipment, than by pursuing more low-tech, high-touch solutions. Do either of you belong to your local Audubon chapters? Doing that was the single greatest improvement in my bird photography. I learned about bird identification and behavior including migration patterns. I also forged relationships with experts who knew the best places to scope out birds. Most of these were fairly obscure little pullouts off a side road; or a friend's vacation cabin+dock on the sound that wasn't in use during the off-season. Our chapter has free monthly two-hour walks, guided by knowledgeable leaders. You can also befriend certain larger chapters on Facebook and receive notices of unusual activity--in my case, whales coming through or snowy owls showing up.

M
11-23-2012, 02:20 PM   #28
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According to the Audubon site, the nearest chapter would take hours to reach - in a jet.
11-23-2012, 03:01 PM   #29
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One thing to consider with bird photography, and I can understand your frustration with the less domesticated species is that there are two types of photos, those which I call record shots, I.e. there is enough detail to prove you saw a particular species, then there are print quality shots, which need to be a substantial portion of the frame. Ducks are rather simple, they are bit, slow moving and predictable, generally if you do not approach rapidly you can predict where they will approach the shore, try finches or warblers. First of all they are tiny, it just gets worse from there
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