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Why is CCDing really so vastly superior to visual?

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#26 GlennLeDrew

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Posted 03 April 2013 - 05:03 AM

Steve,
I wonder to what extent various images of M42 have augmented your own personal '500 hour exposure.'

Anyone restricted to visual only, no matter how long he stared at M42 (to say nothing of the far more numerous fainter nebulae) with any conceivable telescope, could divine its nature as readily as with but a short look at a color image.

Would we have ever visually discovered the fascinating cometary globules in the central 'hole', radiating away from the white dwarf in the Helix nebula (NGC 7293)? Now that we are aware of them, has anyone seen a hint, I wonder? And if so, might not the foreknowledge supplied by imaging have been a help (if not leading to so-called 'averted imagination?')

No matter how long one has gazed through the eyepiece, the end result is still really an impression of less than one second. The accumulated experience will have led to seeing more, of course. But nowhere near to that which the camera can reveal.

Imaging must necessarily be considered vastly superior to a visual view when it reveals things our limited vision cannot. And when it is used for the quantifying of phenomena, such as brightness variation in stars and asteroids, for but one example.

The visual-only acolyte may tend to emphasize the zen of observing, the being in more direct contact with the cosmos, and even the almost 'spiritual' aspect. All valid, for we are emotional creatures. But from an objective viewpoint, imaging in many (not all!) respects is superior.

#27 Astro One

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Posted 06 April 2013 - 06:21 PM

Well said, Karl.

#28 ensign

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Posted 07 April 2013 - 09:12 AM

A recent experience would tend to contradict the title of this thread. I've seen several photos of comet panstarrs lately sent around by email. Last week I managed a peek at the comet through my 9" scope. The view was undoubtedly superior in terms of detail and grandeur to any of these ccd images.

#29 IVM

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Posted 07 April 2013 - 09:41 AM

Most of the photos of this comet that I saw in mainstream information channels looked like someone's first attempt at photographing a celestial object. So indeed the detail seen was about the same as visible to a casual visual observer - my original point!

(Of course my remark is only general, Mike - I don't know what quality photos you may receive by email or if your peek at the comet was casual ;) Even a casual look with experience can beat someone's first attempt at digital imaging. My original point!)

#30 HiggsBoson

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Posted 07 April 2013 - 08:28 PM

IVM

I find you topic interesting. In my view visual and photography are almost orthogonal pursuits. One can do one or the other or both without conflict. For me, seeing Saturn in my own 6” Newtonian is a visceral experience not matched by any photograph. The quality of the image is not very good when compared to those of space born assets but those photos actually enhance my experience because my mind’s eye knows what I am seeing. Similarly, seeing fuzzy suggestions of detail in Andromeda via my optics aided eye provides the same impact not present when I see a detailed photo.

Developing the ability to make those photos is a different challenge. I have done many types of photography including through optical and electron microscopes, many types of video and motion pictures. Astrophotography is by far more technically demanding than those above. However, being hard to do does not imply it is somehow nobler or has greater value than visual observing, quite the contrary.

I am not much of an observer. I take the scope outside for less than an hour about 15 times per year. This is not an obsession for me. I do find it satisfying that I ground and polished a mirror, designed and executed a simple mount. This rig has no motors, wires or batteries yet it shares with me a view of the night sky. I point it, as best I can, with my two hands and explore with my mind.

When I first decided to get a telescope I started with the refractors and moved into the SCTs. Then I settled on the 10” RC from RC Optical Systems. When I realized that this system high tech system was optimized for photography, I decided to build my own simple Newtonian. The RCOS would not be very portable and I would spend most of my time assembling and transporting the thing with the remaining time sitting in front of a computer rather than looking up. I am glad I had my epiphany in time.

#31 aa6ww

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Posted 08 April 2013 - 02:59 PM

On the other hand, "clip clip clip"

Then there are those of us who visually observe because we love to VISUALLY OBSERVE. That's what we do. We purchase what we can afford, are happy with what we have, and don't obsess over specs. We get our joy out of stepping up to the eyepiece and gazing at that swirling galaxy. Or, we go for the next faint fuzzy we can barely detect by nudging the scope, to see something wrong with the sky background and know we've detected an object at the limit of our seeing skill.

Some people get off on self-torture. Others get off on pure pleasure.


I fit into this category. Having observed with larger scopes for years, I now find a fascination out of using smaller higher quality gear and seeing how much I can see just in my back yard suburban skies. Galaxies are much more of a challenge, but open clusters and double stars and even planets fascinate me more now, where as before, I use to just be obsessed with trying to go as deep as I could with larger gear.
I don't care for astrophotography at all however, I call it astrophotoshop. There's too much manipulation of something very basic, some people are very good at it, and that's a skill in itself, but its not for me.
Everyone does have their own reason for enjoying this hobby. I still prefer to go out from sundown to sunset, and make a full weekend out of a Saturday night, even if I'm just in my back yard all by myself with my sports talk on the radio and running two laptops and playing the science guy for one night a week or one night a month.
I like hunting for objects using star hopping skills. I tried GoTo but it was very boring and felt like I was just searching for objects using Google.
I'm finding myself liking the quality views in refractors more also, and spend a great deal of my time with my 4" and 5" refractors, where my larger SCT get very little use, at least when I'm by myself.

Its all for fun and very relaxing and rewarding for me. My family appreciates my passion for astronomy also, and likes that I can be at home in my back yard and enjoying my time.

.. Ralph

#32 galaxyman

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Posted 08 April 2013 - 03:53 PM

Well said, Karl.


Thanks Steve

Hey even Frank once in a while sticks an eyepiece in his 18" f/4.5 dob, and even took part in the observation of Ngc 253 in the Galaxy Log video 11.2012 using his 4.7" f/5 refractor (he of course also imaged it that was used for the video). Though his love is imaging, there is still a place in his heart of looking through an eyepiece once in a while.


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#33 GlennLeDrew

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Posted 08 April 2013 - 07:31 PM

I took the question to mean, "Why do images reveal so much more than can be seen by eye?" Not, "Why is imaging a better pursuit than looking?"

A great many responses seem to be formulated on the latter interpretation, which is an *entirely* different question.

#34 IVM

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Posted 08 April 2013 - 08:39 PM

You are correct, Glenn!

#35 galaxyman

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Posted 09 April 2013 - 12:10 AM

For Glenn I took this part of the original post when I first commented:

Finally – and I really wonder if this is the crux of the matter – it seems to be the nature of man to be demanding of a machine. Which inner drive is applicable to achieving perfection in photography, but not in visual observing.


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#36 GlennLeDrew

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Posted 09 April 2013 - 05:49 AM

Even the crudest, most amateurish, unprocessed DSO image can easily reveal much for which the visual observer would require an aperture easily several times larger. And with just a modicum of attention to technique, the still-inexperienced imager can capture stuff utterly beyond visual detection with any aperture.

The emphasis on a picture of untold toil by masters of the craft tweaking an image with all manner of software and sophisticated techniques bordering on the magical in order to bring out the contribution from every collected photon is overblown.

Back in the good ol' film days, for instance, using a 135mm f/2.8 telephoto, no filter, and ordinary Ektachrome 100 slide film, I unambiguously captured the excessively faint emission nebula Sh2-126 in a single 10 minute exposure. A magnifier was all it required to see the dim red cloud on the slide.

This nebula, about 7 degrees in extent, is illuminated by the O9 star 10 Lacertae, the hottest (but not quite brightest) star in the interesting Lac OB1 association. I suspect this nebula will never be seen visually without electronic enhancement, or averted imagination. :grin: Yet a piggybacked camera with a small lens on inefficient (!) photographic film captured it. This is what one might consider a snapshot, really, which any bumbling klutz could replicate with supreme ease using today's superior--and not necessarily sophisticated or expensive--gear.

#37 galaxyman

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Posted 09 April 2013 - 08:52 AM

Of course Glenn I agree, though remember those first low pixel CCD images in print (Astronomy & S&T)? They showed detail, but were pretty ugly :vomit:

Globs for instance were far better in say my 12.5" dob and a Nagler eyepiece, then what I saw in these early images.

Anyway, I was going in a more "metaphysical" evaluation of the two, which I guess broadened the spectrum of the post.

I'm personally not enamored with doing imaging, though down the road that may change, but for now hand me a quality scope and eyepieces to observe under clear dark skies.

I may not be able to see detail as in those fantastic images we see daily, but that's not what observing and astronomy is about…far from it.

I know you agree with that.


Karl
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#38 IVM

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Posted 09 April 2013 - 10:21 AM

Even the crudest, most amateurish, unprocessed DSO image can easily reveal much for which the visual observer would require an aperture easily several times larger.


"Amateurish" and "unprocessed" would be high praise for the images that beginning CCDers get. I think they get "featureless" instead, same as beginning visual observers. They just know better than to share those true first images and quickly improve their skill. This should not apply if they are expert photographers to begin with (not astro-photographers), but I guess in these days of point-and-shoot this should be rare. Basically I posit that by the time a CCDer shares his or her "first image", he or she has expended as much directed effort improving his or her technique as only few of the visual observers ever expend.

#39 GlennLeDrew

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Posted 09 April 2013 - 11:46 AM

Perhaps I should have been more specific. In my mind I was imagining the beginner who is not so ambitious, and starts with the less demanding 'piggyback' kind of imaging, as did I. You just clap camera to mount, open the shutter for the requisite time, and enjoy the image. Even a wide angle, or for that matter fisheye lens brings out such visual challenges and impossibilities as Barnard's Loop, the lambda Orionis cloud and the humongous Gum nebula, to name but a few.

As Clint Whitman, one of the mavens skulking about the Refractor and Classics forums has practically trademarked, "So easy a (aveman can do it!"

#40 jgraham

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Posted 09 April 2013 - 11:56 AM

Ohhh, everybody is different, so it is hard to generalize. I'll never forget my first night out with my shiny new Meade DSI. I know that my gear was totally inadequate, but I cobbled together what I thought would give me the best shot at success; an Orion StarBlast, one of my smallest and fastest scopes, on a DS-2000 mount, the only tracking mount I owned at the time (also my first tracking mount and my first GoTo mount). I figured that the short focal length of the StarBlast would be more forgiving of the DS-2000’s tracking ability. I decided to go for broke and went after M1 as my first target, I was utterly stunned and shocked at what I saw; a tiny easily recognizable Crab Nebula, something that I had never seen before in any of my scopes. I immediately slewed over to M42, and spent the rest of the night in heaven. If’n I recall right I posted a couple of images from the first night and in fact they may have been the first images taken with a DSI posted on Cloudy Nights. Those were exciting days (nights) right up there with my first view of Saturn. (A little boy in the early 1960s using his Dad’s mountless Sears 50mm refractor wedged just-right in a chain-link fence.)

My gear has slowly been migrating into three groups with some overlap between them; visual, imaging, and camera-assisted observing. Visual tends to be the simplest, imaging tends to be the most sophisticated, camera-assisted observing tends to be older, simpler imaging gear.

My original imaging gear from way-back. I used this for about a year and had a great time with it.

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#41 Sarkikos

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Posted 09 April 2013 - 12:23 PM

It isn't.


+1


+1 The validity of the grand assumption behind the OP's question depends on what is meant by "vastly superior" and who is meaning it. I am a 100% visual observer. And I say that visual observing is vastly superior to CCDing. I have absolutely 0% interest in spending my time and money taking pictures. I want to see objects with my own eyes ... through a nice telescope or binoculars, of course! :ubetcha:

:grin:
Mike

#42 IVM

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Posted 09 April 2013 - 02:08 PM

Mike, what is meant was defined rather narrowly and deliberately in the OP (as revealing nebulous detail). Who is meaning it? I like some aspects of CCDing and deep-sky video but have been so far at least 95% visual myself.

John and Glenn, maybe my premise (that the true first images are so bad they are not better than first visual looks) was indeed wrong. I certainly did not consider piggybacking. Or may it be that you two had been experienced daytime photographers (not the point-and-shoot kind) when you made those first astro images? On nights when our observing field is full, I constantly hear beginning imagers swear loudly. They are getting fuzzy blobs. So surely did I. In fact I recall that my first visual galaxy views were very distinctly better than my first CCD images. DETAIL WITHIN the spiral arms of M81 was among my very first visual views. M51 I imaged during the same outing was an unrecognizable blob.

#43 nytecam

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Posted 09 April 2013 - 04:17 PM

The post title is somewhat loaded and produced the response and feelgood factor the forum expects :grin:

..... I am a 100% visual observer. And I say that visual observing is vastly superior to CCDing. I have absolutely 0% interest in spending my time and money taking pictures. I want to see objects with my own eyes ... through a nice telescope or binoculars, of course! :ubetcha: :grin: Mike

Lucky you Mike to be so uncompremising but sometimes imaging can save-the-day as it did for me last night. Couldn't even spy Regulus naked eye in the murk but got it in finder if extremely dim - then goto NGC 2554 in Cancer and the mag 15 SN was there in a few seconds exposure so I was happy. Eyeballing wasn't an option :grin:

#44 IVM

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Posted 09 April 2013 - 04:30 PM

Yes, Nytecam. Note to myself: do not give a loud title to a lengthy post ;) Especially if it sounds like something entirely different that had already been discussed on the forum. I am just such an inexperienced internet discussant. Sorry all for the confusion and agitation I inadvertently caused ;)

#45 jgraham

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Posted 09 April 2013 - 07:11 PM

"Or may it be that you two had been experienced daytime photographers..."

Heh, heh, I've been imaging since the 60's. My first rolls of film (star trails on 120 Tri-X) were developed by the corner drug store. I quickly stepped up to developing my own film; open trays of chemicals in a dark attic. The rest is history...

#46 GlennLeDrew

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Posted 10 April 2013 - 03:00 AM

I purchased my first camera in '83 (at age 20) and commenced astro-imaging the same year. After initial camera-on-tripod experiments using high speed film, I made a tracker of my own design. I didn't enjoy a period of development as a 'regular' photographer; I dove right into the deep end, so to speak.

#47 nytecam

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Posted 10 April 2013 - 05:09 AM

Yes, Nytecam. Note to myself: do not give a loud title to a lengthy post ;) Especially if it sounds like something entirely different that had already been discussed on the forum. I am just such an inexperienced internet discussant. Sorry all for the confusion and agitation I inadvertently caused ;)

IVM - there's no need for any apologies for your post title - it has provoked some interesting and thoughtful replies which we all welcome. This forum took it in the spirit intended. But if you'd have posted it on the CCD Forum for example it would have been taken at facevalue and the response likewise :grin:

#48 Starman1

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Posted 13 April 2013 - 06:04 PM

Compare the eye, and what it sees in the 1/30th second image time frame it downloads to the brain, with what ANY camera sees in 1/30th second.
The eye is VASTLY superior to the camera.

BUT, though the exposure length cannot be modified for the eye, it CAN for the camera. And adding up all those photons does give us a better view of the faint objects we love to view.

The one exception seems to be planets. I have never seen a photo of Jupiter that equals the crisp sharpness that can be seen with the eye in a decent-sized scope. Part of the reason is seeing--with the eye, we WILL catch that 0.2" resolution 3-second period in the middle of a minute of observing. With the camera, we won't. And part of it is the process of stacking will only resolve to the lowest common denominator, and that is probably the equivalent of an average as seen by the eye, and excludes the moments of superb clarity we catch with the eye.

My primary objection to photography is that it takes too long. I viewed 75 galaxies, 6 planetaries, and 2 clusters over the last night I observed (only actually recorded my observations for 20 of those objects). If I were photographing the objects, I might have shot, what, four or five? If you had one night a month to observe under dark skies, which would you do?

And photography is very expensive. A decent CCD camera is $2K-$5K, and that can buy a whole case of high-end eyepieces. I certainly don't cast any stones at those who image, but I often wonder if they really enjoy looking at the sky.

Now, for the person with an observatory in dark skies who photographs with one scope while looking at the sky with a nearby 20" dob, I can only say :bow:

#49 GlennLeDrew

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Posted 13 April 2013 - 07:25 PM

Don,
With something like a Mallincam, a pretty brisk pace can be maintained. Over the course of a night I can image 50 different objects, and that's taking the time to manually point and frame the targets with my non-GoTo mount. If the mount could reliably point for me, I could build a nightly album of easily 100 objects. And for nebulae and galaxies, those 1-2 minute exposures would contain detail and color I could never see.

#50 chaoscosmos

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Posted 15 April 2013 - 04:30 AM

I was going to say something similar to what I think Don is referencing. That is, photographs can show vastly more- in a way- but the eye sees nuance that can never be replicated in a photograph. So while visual observing through an eyepiece may see less of what's there in one sense, it sees more of that which it can see. The subtlety of light and clarity can't be replicated in a photograph, but a photograph can show things we couldn't observe without it.






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