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Old May 18, 2010, 5:45 AM   #1
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Default Double Lens Attachment on Canon

I have a Canon A590is. I would like to attach in its adapter a 2X 52mms lens with a 72mm front thread. Then, I will attach a 3X 72mm lens in front of the 2X 52mm lens. Will this setup work so that I could have a 24X total of optical zoom?
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Old May 18, 2010, 6:22 AM   #2
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I have a Canon A590is. I would like to attach in its adapter a 2X 52mms lens with a 72mm front thread. Then, I will attach a 3X 72mm lens in front of the 2X 52mm lens. Will this setup work so that I could have a 24X total of optical zoom?

Probably not. You'll likely have major autofocus issues and even if it did work, the resulting images would probably be of very poor quality.
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Old May 18, 2010, 6:28 AM   #3
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You can do all that, but remember that the A590is lens is a complex optical system. As with any complex optical system, it has its flaws. A 2X lens serves to magnify those flaws, plus add some of its own. When you add the 3X lens, it magnifies the flaws in the lens in the A590is and the flaws in the 2X lens, and adds its own. It will physically work, but you may not be pleased with the results.

I also want to point out something that you may have overlooked. The zoom lens on the A590is has a minimum focal length of 5.8mm and a maximum focal length of 23.2mm. That "4X Zoom" specification is the ratio of the minimum focal length to the maximum focal length. (23.2mm / 5.8mm = 4) The 2X lens doubles the maximum focal length (23.2mm X 2 = 46.4mm) as well as the minimum focal length (5.8mm X 2 = 11.6mm), so the zoom is still 4X (46.4mm / 11.6mm = 4.) When you add the 3X lens, it triples the maximum focal length (46.4mm X 3 = 139.2mm) and the minimum focal length (11.6mm X 3 = 34.8mm.) Even with all those extra lenses, the A590is will still have a 4X zoom (139.2mm / 34.8mm = 4.)
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Old May 18, 2010, 6:34 AM   #4
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If the double lens assembly is to be screwed to the camera lens then I would be concerned about excess weight on the camera lens overloading the focus motor as well as overloading the camera lens mechanism.
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Old May 18, 2010, 6:36 AM   #5
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Yeah. What he said.
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Old May 18, 2010, 11:58 AM   #6
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Originally Posted by vinjayz View Post
I have a Canon A590is. I would like to attach in its adapter a 2X 52mms lens with a 72mm front thread. Then, I will attach a 3X 72mm lens in front of the 2X 52mm lens. Will this setup work so that I could have a 24X total of optical zoom?
What brand are the 2x and 3x lenses and what price. There's a good chance if they cost less that $100 the 2x is really 1.2x and the 3x is really 1.3x.
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Old May 19, 2010, 12:39 AM   #7
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Quote:
Originally Posted by Bob Nichol View Post
If the double lens assembly is to be screwed to the camera lens then I would be concerned about excess weight on the camera lens overloading the focus motor as well as overloading the camera lens mechanism.
This camera uses an on-body adapter to support add-on optics, so overloading the lens mechanism isn't an issue. I use a similar adapter on my Zony DSC-V1 to mount various filters, and a not-dissimilar adapter on my DSC-P10 for wide- and tele- optics -- which suck.

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You'll likely have major autofocus issues and even if it did work, the resulting images would probably be of very poor quality.
From my experience, autofocus isn't an issue, but image quality is -- it sucks. Canon makes add-on glass for the A590is, and it may be the best possible -- but it will still suck. Image quality goes in the toilet. Maybe that's desirable, maybe not. Maybe we WANT edge distortion, softness, flaring, like a Holga's plastic lens. I've shot with such crap optics, knowing that the results wouldn't really be photographic quality -- just more source material for shooping. Call it art.

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Will this setup work so that I could have a 24X total of optical zoom?
No. No, it won't. As TCav said, no matter what glass you put in front of the lens, you'll still only have 4x zoom. And as ac.smith said, those magnifiers are likely to be much less powerful than you expect.

It helps to know the history. Wide and tele adapters were introduced for cine and video cams long ago. Cine and video optics are NOT in the same league as still-camera optics. You can get away with crappy optics for moving images, because of the way human vision sees such. We just don't notice that they're crap. I mount 1.5x tele and 0.5x wide optics from my dad's old Hi-8 Handycam, the best available then, on my Sony DSC-P10. Shooting video, they're fine. Shooting stills, they suck.

And I've added more expensive optical adapters to my dSLR, and they STILL generally suck. The exception: Raynox close-up lenses. These are non-simple optics that deliver remarkably good IQ and aren't terribly expensive. Raynox also makes auxiliary lenses for camcorders, which could probably be used on P&S's, but I don't know how they rate quality-wise. And whatever you add WON'T provide a long zoom and WILL degrade the images.
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Old May 19, 2010, 3:36 AM   #8
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Thanks guys for all your thoughts. I wouldn't have realized by myself the idea you've shared TCav about the optics and also RioRico for differentiating videocorder and camera optics. It is so good discovering this forum. Hehe
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Old May 19, 2010, 3:51 AM   #9
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Any comment on slave flash for Canon A590is?
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Old May 19, 2010, 6:23 AM   #10
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Any comment on slave flash for Canon A590is?
This is definately a different topic, and you'r only likely to get responses from people interested in the original topic. I think you should ask this in a new topic, and you'd probably get a better response rate if you post it in the Canon P&S Forum.
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