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09-11-2009, 08:53 AM   #31
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Image Analizer is good, but quite unstable. Many "Out of memory" messages.
It is also faster most of the time as uses all available cores.
Note that it uses worse deconvolution algorithm. And it is much harder to tune.


Last edited by tr13; 09-11-2009 at 08:58 AM.
09-11-2009, 08:58 AM   #32
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One of the main points is to work in RAW. And it is better to work on completely unprocessed RAW.
DxO Optics seems to do similar thing.
I also believe that Image Analizer can be tuned quite good is you shoot special targets on each zoom distance of the lens.
One of simple improvements is to have spherical intencity function to make radius and amount bigger towards corners.
I really saw amazing results for my average lenses. In 50% view they become identical to best ones.

Last edited by tr13; 09-11-2009 at 09:15 AM.
09-11-2009, 09:10 AM   #33
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QuoteOriginally posted by newarts Quote
The out-of-focus image of a point is roughly a disk. In effect, deconvolution reverses the process, restoring each disk to a point.

It can do a lot to improve a poor lens' performance. This is not a fake improvement if the way the lens focuses the image of a point is known.

In principle, there is no limit to which resolution can be increased, if one knows (or can estimate) exactly how an out-of-focus point is blurred. But in practice it isn't very easy to do & requires a lot of computation.

For example, say a lens focuses a point with an intensity profile like a hill, /\, software can find the center of the hill and replace the hill's profile with a point. Perfect resolution!

It is not all that easy to do, but you get the idea.

Dave
Wow. Like something out of a science fiction movie or novel.
09-11-2009, 09:13 AM   #34
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Thanks TR13

QuoteOriginally posted by Spock Quote
Wow. Like something out of a science fiction movie or novel.
Not really, it's used already by astronomers (ie NASA & hubble), and microbiologists (ie people photographing using electron microscopes etc)

09-11-2009, 09:14 AM   #35
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Quite soon(is Canon or Nikon engeenears are smart) you'll see mostly software stabializer.
If you have recorded 3 axis accelerometer readings you could make very good movement deconvolution on RAW image. I believe that it is not my idea and someone in astrophotograthy already uses this.
09-12-2009, 03:51 AM   #36
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QuoteOriginally posted by Nass Quote
Thanks TR13

Not really, it's used already by astronomers (ie NASA & hubble), and microbiologists (ie people photographing using electron microscopes etc)
Deconvolution is standard for all astronomical image processing packages, even for amateur applications and has been for years. As some of the most advanced image processing packages are free (MIDAS by ESO for instance), it should be possible to use the deconvolution part of these packages and make it into a PS plugin. If I were only a programmer, but I have no clue...

The only software for Mac, which I tried in the past is NIH Image (developpped by the US Health Authority), but it is unstable and does only support a few file formats/image sizes. So it was pointless with photographic images.

Ben
09-24-2009, 07:10 AM   #37
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Lol guys Sorry I've been out for a few days but wow so many answers! haha I was wondering, is Vivitar a good lens Brand? They're not too expensive the ones I've seen, could I expect Tamron/Sigma quality from it?
09-24-2009, 11:52 AM   #38
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Vivitar for the most part doesn't make lenses; they buy lenses form other manufacturers and put their names on them. So some lenses with the Vivitar name are better than others. Of course, that's true even of companies that 8do* make their own lenses - you really can generalize a whole brand. You've got to ask about specific lenses.

09-24-2009, 12:19 PM   #39
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QuoteOriginally posted by tr13 Quote
Quite soon(is Canon or Nikon engeenears are smart) you'll see mostly software stabializer.
If you have recorded 3 axis accelerometer readings you could make very good movement deconvolution on RAW image. I believe that it is not my idea and someone in astrophotograthy already uses this.
regardless of stabilization (sensor, lens or software ), it simply won't corect correct in other than 2 axis. THere is simply no way for the stabiliation system to keep you from mofing closer to or away from the subject.

as for the OP and where to get a good tele, I would second the comment someone made for the SMC300F4. I would also recomment coupling it to the SMC-F 1,7x AF TC. Sure it will cost more than the 55-300 he is looking at, but it is a really good tele even at today's prices. There are usually 1 or 2 on Ebay or in the market place at any time
09-25-2009, 07:05 PM   #40
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Yeah I get ya, that is why I don't buy Sigma lenses straight up, they got good and not so good lenses I've had both sides before. But in general would Vivitar as a brand be up there along with Sigma and Tamron? I've heard so many Mixed reviews, I'm interested in particular this M42 lens I saw it was a Vivitar 135mm 1: 2.8 Auto Telephoto Lens.

Could I expect sharp images from this particular lens?
09-25-2009, 10:00 PM   #41
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As I said, Vivitar doesn't generally make lenses - they sell other people's lens. So by definition, their lenses are exactly as good or bad as those other people's lenses. Some are indeed very good, some are indeed very bad. Again, you need to say which lens you mean.

EDIT: Either you edited your post to name a specific lens, or I'm blind. My apologizes if it's the latter. But luckily, my point still turns out to stand, because often with these rebranded lenses, it's not enugh to even name the focal length and maximum aperture - you need to go by the serial number or manufacture date to tell which version it is / who actually made it.

Last edited by Marc Sabatella; 09-26-2009 at 11:29 AM.
09-26-2009, 01:16 AM   #42
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As Marc says, which one. There seems to be about 7 Vivitar 135/2.8s

Vivitar TELEPHOTO (Early, T-mount? unknown maker)
AUTO Vivitar (Made by Tokina)
AUTO Vivitar TELEPHOTO (Made by Komine)
AUTO Vivitar TELEPHOTO (Made by Tokina)
AUTO TELEPHOTO (Made by Komine)
AUTO TELEPHOTO (Made by Tokina)
AUTO TELEPHOTO CLOSE FOCUSING (Made by Komine)


Edit: Serial numbers beginning with 28 are Komine and with 37 are Tokina

Last edited by alfa75ts; 09-26-2009 at 01:18 AM. Reason: Additional info
09-26-2009, 06:17 PM   #43
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Ah ok, yeah it's made by Tokina the seller says. He has one by Komine too if I was interested. Which is good/bad better/worse?

Ah PS: I bought a Tamron 80-210mm for Au$110 bran new in box and all and absolutely love it, but, at 210mm it's not so sharp, I tried some moon shots and you can't get a sharp circumference as I could with my Sigma 80-200mm manual focus lens. But I'm happy with it, has really sharp pictures at 80 to about 180 I'd say.
09-27-2009, 02:38 AM   #44
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QuoteOriginally posted by Andrezao Quote
Ah ok, yeah it's made by Tokina the seller says. He has one by Komine too if I was interested. Which is good/bad better/worse?
I don't have either, check the reviews. People there seem to expect the Komine to be better but I doubt if there's much difference.

Going from recent eBay completed auctions you should be paying A$20 to A$40 and at that price I expect you're going to get more than your moneys worth.


QuoteOriginally posted by Andrezao Quote
Ah PS: I bought a Tamron 80-210mm for Au$110 bran new in box and all and absolutely love it, but, at 210mm it's not so sharp, I tried some moon shots and you can't get a sharp circumference as I could with my Sigma 80-200mm manual focus lens. But I'm happy with it, has really sharp pictures at 80 to about 180 I'd say.
Probably atmospheric dust I'd try it with mine but will have to wait for clear skies.
09-27-2009, 03:57 AM   #45
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QuoteOriginally posted by ManixZero Quote
Like many zoom lens owners I tend to use it at its extremes ie 300mm and although it can struggle with fast moving aircraft (focus wise) its overall performance at 300mm isn't disappointing.


A Swan

All taken with the 70-300mm at 300mm.

Cheerz MZ
No clue why you insist on using the extreme end. If you back off from the extreme and shoot at around 250mm, the gain in IQ alone will compensate more than that minor 50mm difference.
By design the extreme end of a consumer zoom has been extended with little regard for IQ. The wider the FL range the worse. And the extreme end (300mm) should be avoided unless for snap shot purpose.
BTW M*300mmF4 was mentioned which is not much more expensive than a new consumer zoom. I would second that if manual focus does not intimidate you

Daniel
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