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Does Image Stabilisation, as found in popular, inexpensive, compact, digital, still cameras, help or hinder taking astro "snaps" of the Moon and (properly filtered) Sun at the eyepiece?
Does IS help or hinder taking videos using such cameras at the eyepiece?
Compact digital cameras exist in their hundreds of millions and are often the only camera in the house these days. So they should be relevant to amateur astronomy. They require no laptop or sheltered PC beside the telescope so compacts offers a great deal of flexibility and room for experiment. They also record images at almost zero cost once the camera is purchased. Digital compact cameras function similarly to a film SLR in that the TTL image is available until the last moment. This removes much of the guesswork in centring and focussing the image.
I am not remotely interested in your opinions on webcams and processing. Or the advantages of any other kinds of cameras. My aim is to discuss and encourage an accessible imaging platform open to all kinds of instruments and levels of experience. From my own experience I strongly recommend the use of a camera lanyard.
Some of my own snaps appear on my telescope blog. Nothing remarkable (at all) but they do record some special moments in astronomy. I simply held the camera up to the eyepiece and took a lot of "snaps". Some are "luckier" than others. My results would improve if I used the camera adaptor I built but I prefer the spontaneous freedom of the hand held camera. I have a sturdy mounting and massive pillar stand which lets me get away with it more often than not.
Chris.B wrote: > Does Image Stabilisation, as found in popular, inexpensive, compact, > digital, still cameras, help or hinder taking astro "snaps" of the > Moon and (properly filtered) Sun at the eyepiece?
For me it helps with the Moon.
I have a Sony DSCH 7 which has a zoom up to about 462mm (35mm equiv) and it really does make the difference with hand held shots of the Moon. I do have to use manual focus, and manual settings for proper exposure, but that is no big deal at all. The image stabilization makes the difference, otherwise I would have to use a tripod.
This is a cheap prosumer camera, but I get decent enough pic's for me, I'm happy.
> ... > Compact digital cameras exist in their hundreds of millions and are > often the only camera in the house these days. So they should be > relevant to amateur astronomy....
> I am not remotely interested in your opinions on webcams and > processing. Or the advantages of any other kinds of cameras. My aim is > to discuss and encourage an accessible imaging platform open to all > kinds of instruments and levels of experience. From my own experience > I strongly recommend the use of a camera lanyard. > ...
This is Old Business, and it has been debated ad nauseam. The issue has been settled; the use of consumer-level and "pro-sumer" digital cameras to make pretty pictures with a telescope is an established practice. Many people have told me that this photo that I made with my Canon 40D is a pretty picture <http://www.primordial-light.com/images/thors-helmet-091216-lg-1.jpg>.
This to the chagrin of snooty purists, who feel that a cooled, research-grade camera is the only kind worth using in astronomy, even if one is not doing research. My thought (and I also use an STL-11000M) is that, in any situation and in any field of endeavor, the tool that produces the desired result with the minimum of labor is the right tool.
> Let's see how long you can stick to the subject. If at all.
I'm not _entirely_ certain that insulting one's audience is the best way to appeal for participation. In any case, I have stuck to this subject as long as I am going to. Any additional responses I may make in this thread will have no relationship to the original topic.
Davoud
-- I agree with almost everything that you have said and almost everything that you will say in your entire life.
On Tue, 9 Feb 2010 06:08:23 -0800 (PST), "Chris.B" <chri...@nypost.dk> wrote:
>Does Image Stabilisation, as found in popular, inexpensive, compact, >digital, still cameras, help or hinder taking astro "snaps" of the >Moon and (properly filtered) Sun at the eyepiece?
It depends on the method of IS used. Some cameras use the optical image itself as the feedback for the stabilization. I would expect these to give good results with through-the-EP shots and stabilization enabled. But some cameras use inertial sensors to control the stabilization, and I'd expect these to perform poorly, since the amount of motion being compensated for will be higher at the EP than the camera control system expects given its focus at infinity.
I think most inexpensive digital cameras these days use the optical stabilization approach, so they will probably work well with stabilization enabled. The inertial systems are more likely to be found in stabilized lenses for DSLRs, and few people would use such cameras for through-the-EP imaging, since prime focus imaging generally produces much better results. _________________________________________________
My STL-11000M was at SBIG for a rehab at the time I made that picture, or I might have used it instead. I doubt if I would have gotten a better photo, just a larger field. Notes are at <http://www.primordial-light.com/deepsky6.html#thor>.
So, are you with the majority (in fact it is unanimous up to now) -- is it a pretty picture or not? :-)
Davoud
-- I agree with almost everything that you have said and almost everything that you will say in your entire life.
Many thanks to those who have responded so far. The reason I asked about IS is that I had rather more success with an older, non-IS camera. Though this may have been due to the way I used the nose of the old Sony camera lens to align with the eyepiece rubber eyeshield. It was a perfect fit despite the disadvantages of the tiny viewing screen. No doubt the secure location ensured the mass of the instrument was able to resist my involuntary hand movements to hold the camera firm and provided alignment in all planes. Later cameras have larger lens housings so are not self-locating in the rubber eyeshields. I hoped for a technical reason why IS would work (or not) under these special circumstances and am most grateful for the useful information provided.
I really ought to use my home made camera holder but grew tired of removing the camera to run indoors every ten minutes to download my latest images just to see if I had anything useful. There was always the danger I would damage or drop the camera in the pitch darkness while fumbling with cold hands or while wearing gloves. The lens would also extend further before retracting to the closed position which posed a serious long term risk of mechanical damage if its movement was blocked.
Because the lens housing of a compact camera retracts and changes length and form with focus and zoom settings it was never straightforward to attach a compact camera to a telescope other than by the tripod mounting bush. However, while scribbling this response, it has just occurred to me that I just need to turn up a felt or rubber-lined tubular adaptor. One end to to fit snugly over the largest section of the drawtube "head" and another diameter to locate the nose of the camera lens housing precisely centred and at the correct distance from the eye lens of the eyepiece. Since the adaptor will only be used for temporary location there is no need for the camera "nose" to be clamped or even held too firmly. Thankyou for supplying the necessary inspiration. :-)
Chris.B wrote: > Does Image Stabilisation, as found in popular, inexpensive, compact, > digital, still cameras, help or hinder taking astro "snaps" of the > Moon and (properly filtered) Sun at the eyepiece?
> Does IS help or hinder taking videos using such cameras at the > eyepiece?
It could be a bit of both. Assuming it is capable of adjusting for motion blur via tip tilt I would expect it to help a bit.
One experiment I intend to try is to capture video through the scope on my new IS Canon Ixus to see if the IS can provide an element of realtime tip-tilt correction fast enough to improve planetary viewing.
> Compact digital cameras exist in their hundreds of millions and are > often the only camera in the house these days. So they should be > relevant to amateur astronomy. They require no laptop or sheltered PC > beside the telescope so compacts offers a great deal of flexibility > and room for experiment. They also record images at almost zero cost > once the camera is purchased. Digital compact cameras function > similarly to a film SLR in that the TTL image is available until the > last moment. This removes much of the guesswork in centring and > focussing the image.
Main annoyance is that few of them have a cable release option and all of them burn through batteries to keep the shutter open for time exposures.
> Some of my own snaps appear on my telescope blog. Nothing remarkable > (at all) but they do record some special moments in astronomy. I > simply held the camera up to the eyepiece and took a lot of "snaps". > Some are "luckier" than others. My results would improve if I used the > camera adaptor I built but I prefer the spontaneous freedom of the > hand held camera. I have a sturdy mounting and massive pillar stand > which lets me get away with it more often than not.
> Remember this forum's dreadfully poor signal to noise ratio?
> Let's see how long you can stick to the subject. If at all.
You invite some offtopic (relative to the subject heading) comments by posting such an interesting article on doing up Fullerscopes old mounts. I am impressed. The older castings look a lot more businesslike.
On Feb 10, 9:51 am, "Chris.B" <chri...@nypost.dk> wrote:
> Many thanks to those who have responded so far. The reason I asked > about IS is that I had rather more success with an older, non-IS > camera. Though this may have been due to the way I used the nose of
I've pointed dozens of cameras at the sky in one way or another. I guess this is the natural thing to do when you are forced to work with cameras and have more than a passing interest in astronomy. My observations so far: most IS enabled cameras are useful for hand held shots. Starting with the Olympus 2100 UZ back in 2000, it became possible to shoot Jupiter's satellites handheld, catch craters on the Moon or show Saturn's "oval" shape. Nothing spectacular of course, and still a bit shaky, but it was a bit like being Galileo again... At the other end of the range, shooting the Moon or Jupiter hand held with a Canon 5D MKII/1D MKIII and a 300 2.8 IS lens gives decent results, but you'll need a few shots to get a good one.
I've always had sub par results when connecting P&S to scopes. Their signal to noise ratio is usually quite poor, most of them are jpeg only, and the IS doesn't make any difference on a decent mount. Keep in mind that these systems (except in high end video cameras, but even that true digital image stabilization has issues) are based on gyroscopic sensors, not on image processing. Also, in-lens stabilization systems change the light path somewhat, while sensor based stabilization systems move the focal plane a bit which has two consequences: a possible lack of sharpness by navigating around the critical focus point (usually, doesn't matter much because you aren't really doing hi-res work) and a confused auto-focus system.
Anyway, I guess this depends on whether you find your pleasure in the process or in the results.
One fun test I've had in mind is connecting an Exilim EX-F1 to a big dobsonian. The big dob would take care of the signal to noise issue on bright objects, the high frame rate of the EX-F1 could yield interesting results. But I don't expect it to come any close to what can be achieved even with webcams.
Thanks again for your interesting comments. It will be fascinating to see where P&S digital photography goes as the mobile phone increasingly becomes the cutting edge for highly compact imaging platforms. Demand for much higher sensitivity and better image and video quality will no doubt continue to drive the medium forwards for our own benefit. Tomorrow's technology will seem much like magic by our present standards. Today's compact digital cameras offer four times the resolution, four times the focussing screen size and 5 times the zoom range of my first digital camera bought only a few short years ago for exactly the same price. The size, shape and weight have all changed for the better too.
Having dragged an SLR and a a bag of lenses about for decades I couldn't imagine going back to film and crappy developing services taking several days to a week when I can take and process my own images by the thousand. In fact I often take more pictures per hour than I took in several months in the past. This is a priceless freedom I wished I had enjoyed years ago as I hung my camera from my 5" f:15 refractor to capture fuzzy shots of the Moon at prime focus.
Mankind has never enjoyed a more affordable and convenient way of imaging their daily activities than it has today. The ability to record and share our hobbies and pastimes is something I sorely miss from my own past. Today I would take dozens of snaps and HD videos to ensure I have every conceivable angle covered and then have the freedom to share it online, immediately with a global audience. Until the Internet came along I had only met one other telescope maker in my entire life. Now my own very narrow interest hobbies have attracted tens of thousands of viewers. Pre-Internet I might as well have been the only person in the world with a particular interest. Finding any information on these minority interest subjects would have been all but impossible without access to a major reference library.
I hope today's generation appreciates this incredible change in their ability to find and communicate with those who have similar interests. I think it tragic to see YouTube monopolised by morons muddying this incredible gift to mankind. Imagine if you had said to somebody twenty years ago that you foresaw the ability for everyone (except those living under vile dictatorships) to share high quality images, music and videos with the entire world? They would have locked you up! Now the masses waste this opportunity like they discard some tasteless take-away. Perhaps it is because it is almost free? They understand nothing and value it less unless they are told it is worth stealing? It is still early days for the Internet to have matured much but I hope that it grows up in beneficial ways for all of mankind. Not just for those who can afford to participate and who just happen to live in a relatively free and affluent democracy.
> Thanks again for your interesting comments. It will be fascinating to > see where P&S digital photography goes as the mobile phone > increasingly becomes the cutting edge for highly compact imaging > platforms.
At least for those who demand blurry, poorly lit snapshots. Today's "smart" phones do an incredible number of things amazingly well, but photography is not one of them.
Things have undoubtedly improved with the introduction of Photogene for iPhone, but it will be a long time before phone cameras replace compact digital cameras (for those who require more than blurry, poorly lit snapshots, I mean).
What I like about compact digital cameras is that they are not necessarily limited to point-and-shoot only; my wife's and my Olympuses offer a high degree of manual control so that a knowledgeable snap shooter can control depth of field, compensate for backlighting, and manage other parameters that lower-end compact cameras do not deal with.
Davoud
-- I agree with almost everything that you have said and almost everything that you will say in your entire life.
> What I like about compact digital cameras is that they are not > necessarily limited to point-and-shoot only; my wife's and my Olympuses > offer a high degree of manual control so that a knowledgeable snap > shooter can control depth of field, compensate for backlighting, and > manage other parameters that lower-end compact cameras do not deal > with.
The Panasonic LX3 that I got my wife for Christams is a very impressive compact camera. The only "limitation" is a small zoom but I much prefer its fast lens to a long zoom for a lot of shots.
I'm going to try strapping it on my SCT for some night shots.
On Feb 23, 9:49 am, Scatter <u...@eeepc-r.domain_not_set.invalid> wrote:.
> I'm going to try strapping it on my SCT for some night shots.
Try holding the camera up to an 18mm, or longer focus, eyepiece on the Moon or planets to take snaps. You could surprise yourself.
It needs an eyepiece with a large enough eye lens to allow a full beam of light to enter the camera lens to fill the sensor. Otherwise there is heavy vignetting. Plossls seem to work well.
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