Camcorder & Skywatching Questions

Originally posted by dainoyfb
As for range finding I generally agree with CHRLZ, except that perhaps a few hundred meters might be a bit pessimistic.

Yep, that's me! To be fair, I did say you *might* get out to a kilometre or more, but the methodology would have to be VERY good! I'd want to see some daytime tests first...

I will also direct you to this thread of mine which explains a method for determining the size and velocity of an object if known background objects are present in the scene.

That's a very useful discussion - well done. Waveguide3 (who is *very very* cluey on such matters) raised the most important proviso - I was pleased to see you acknowledged it in your post here.


One of the worst (and most common) mistakes beginners make is the simple belief that everything the camera records is properly resolved. An out of focus blob (even if it is only a 'little' o-o-f) is effectively worthless for any inference of shape or size. When using long focal lengths, the difference between a focused image and a worthless blob of 'bokeh' is tiny.

Once you have good optics and have learnt how to precisely focus, then you can start addressing all the other things that will screw up your images (steadiness of camera, not including background, not getting the exposure right..).

Hey, you're right - I am a bit of a pessimist...

But I call it being a perfectionist!

Superiorraw, You may want to learn how stereoscopic optical range finders work.

Here is a medium sized one that ranges out to 15 kilometers and is used for artillery targeting.

Here is a tiny one that ranges out to 1 km. The design was very common for hunters and snipers until laser rangefinders came onto the scene.

Generally, the wider they are the greater the practical range they have.

Some modern ones port the stereo components into a single camera. Despite the effectiveness of modern laser range finders optical designs are still used so that the target remains unaware that it is being ranged.

The availability of parts at the consumer level these days make home built versions of these devices practical and on par with amateur telescope building.

CHRLZ, thanks for your compliments! Good to see some technical pursuits going on here.

Thank you guys so much for posting on this thread.
I am pleased to also report due to a cheque deposit in my bank account I might not have to wait until August to purchase the Camcorder I've been saving up for. Priorities are that I am going to clear the £270 debt that I owe first, but i should be left with enough to put a serious deposit if not full purchase for the videocamera. I really think my full interest will literally take off once I get better equipment.

Thank you to both of you for putting up your advice and opinions on the distance thing. I've never been any good at distance judging, I dont even know things like the height of some clouds. I know we have different banks of clouds where some are higher than others.

I've recharged the battery on the 8mm videocamera. I plan to at least take some video footage of other comparable objects in the sky. Which I will then compare with my footage of the 22nd.

Thanks also to dainoyfb for the links on the rangefinders. As always I am very appreciative of having this site/thread to be able to address any concerns or questions I have.

I like cameras that have a lot of manual settings that can help you sort things out for quirky situations like glue to one end of a telescope. Most devices now will still not fully automatic, no manual setting if you irritate.

Just a quick update here for this thread - I've paid off my remaining £270.00 of debt. I have to wait for those payment to be debited from my account but I should at some point within 2 weeks be able to get the Panasonic SD60 VideoCamera that I want.

I called up the local shop and he can definately get it me, I am soooo excited now. All this saving and stuff has been quite agonising. But I am most definately sure it will be worth it in the long run!

:-)
In friendship

hi superiorraw,
thanks for inviting me to your thread, great work and very interesting, star and flag but i don't know where i fit in as i know nothing about skywatching or the equipment used. but it seems that you have found the best expertise you could possibly ask for in CHRLZ and dainoyfb.

i do have a little suggestion on the following question that you asked earlier though:

"2. Is there anything you could buy, say, erm.. an estimator? something like a distance calculator that measures distance via zoom used? I'm just wondering about actual approximate distances. Something I always have trouble with is distance. If someone asked me to calculate or speculate a distance I saw an object hovering i'm really not that confident in my own guesswork."

maybe you could read up on sniper techniques and how they estimate/calculate their distances, also maybe you could use a "sniper spotting scope" fixed to your rig to help, you could first set a benchmark to work off by using a faraway building at a known zoom level to set a kown distance which you can then use to work out or gauge other distances,

also another suggestion is that as you live in manchester, maybe you could use manchester airport and approaching planes as some kind of reference point by finding out as much info as you can and also observing aircraft approach and landing patterns, heights and distances, maybe film a few to help and maybe that would give you a bit of experience in filming moving objects as well as judging heights and distances.

i apologise in advance if all this has been covered as i haven't had chance to read and take everything in just yet.

also a message to the experts! i openly admit i am way out of my league here and don't know anything about skywatching or equipment so please feel free to disagree with or correct anything ive said.

thanks

rich

Originally posted by RICH-ENGLAND
hi superiorraw,
thanks for inviting me to your thread, great work and very interesting, star and flag but i don't know where i fit in as i know nothing about skywatching or the equipment used. but it seems that you have found the best expertise you could possibly ask for in CHRLZ and dainoyfb.

well mate, i asked you as you seemed very interested in discussing possible distances and whatnot on the tremiti photo. Although both of us are amateurs in comparison to the science and tech field and dont have the info - its never to late to learn, at least i thought that if you held such an interest and wanted to jump in, you'd have somewhere to ask for advice.

I learned a lesson from an old college tutor a while back ''dont be afraid to ask questions if your unsure or dont know'' and its so true in this field. All we can do at this stage is ask positive probing questions and hope that we better educate ourselves and prepare for future photographs or video footage.

As I mentioned in the other thread, the aim here is counter-balancing any known problems with previous UFO footage or Photographs, if someone says the photograph or video lacks detail - how can we improve that?
if they say they cant tell the distance or size of object - how can we tackle that issue for the next sighting. - i'm hoping that those with an interest in UFO / UAP identification and skywatching, whether they be complete amateurs or experts can chime in here, particularly as the more of us collate our questions and ideas. the better shot we have I feel of improving our footage at a later date.

So yeah, i did refer you to this out of common interest and for me personally it doesnt matter how experienced or inexperienced you are, if it helps me and helps others that can only be a good thing.

In friendship
Richard

[edit on 1-7-2010 by RICH-ENGLAND]

*update*

Almost there I am pleased to announce that this morning I put the order in for my Video Camera. I will be getting it either on Monday or Thursday next week.

I am sooo excited. I've been looking on Youtube at some zoom examples of what the panasonic SD60 is capable of and it looks... absolutely brilliant!!
(refrained myself from swearing)

It will most likely take me a few days to familiarize myself with the videocamera but I shall post another secondary update as soon as I get it next week. (Yes I have the money in my bank waiting). Nothing can stop me now!

I feel so energised. I know personally that my previous footage obviously had some issues in terms of quality and capability, thankfully this is one hurdle I will be able to overcome.

Once I get familiarized with this equipment I shall proceed to stage 2 of my operation! - Again I would personally like to thank everyone for their continued imput and patience as I am still learning as I go.
In friendship

Richard

Originally posted by Superiorraw
*update*
Almost there

I am pleased to announce that this morning I put the order in for my Video Camera. I will be getting it either on Monday or Thursday next week.

GO, Richard!! Best of luck with it, and spend the time to learn it *backwards*. Please *do* RTFM as they say!!

A couple of tips (although I think you already know them!) - spend lots of time familiarising yourself with the control locations in daytime, and then practice with your eyes closed on the important ones, until it becomes second nature.

Do lots of tests on known objects, to see how the manual focus works, how to adjust exposure, what it looks like when defocused (ie bokeh shapes - and make sure you check all of the image area, and at different zooms - the shapes will change!!

The Moon, stars/planets (- have a go at resolving any of Jupiter's moons - then we'll see how good your lens/sensor is!), and distant streetlights are all good targets (but do some daytime stuff too, of course), and once you have experience with that sort of stuff, you will better be able to recognise what is real, and what is just your camera/lens/aperture effects.

Let us know when you have some stuff to look at, and don't be afraid to post the rejects and experiments, and ask questions - just keep the videos fairly short for those of us on limited bandwidth!

And don't forget, no matter how good the image stabilisation might be - USE A TRIPOD!!!! Try to embed the picture of your camera on a tripod into your psyche. The camera should look weird and unsupported when not on a tripod...

I'm hoping to drag another ATS member over to these threads as well - one with a LOT more video knowledge..

Hey Chrlz,
Yeah. I plan to put up some footage at some point. I'm going to start at least with some zooms and familiarize myself with all the controls and all the features.

As you know from my previous posts on ATS. I have quite the obsession to learn. I've got a tripod already that I used with the 8mm Hitachi. I never did get round to recording aircraft at night with that to match up to the 22nd footage because I found out what it was. In any case I quickly learned with the hitachi that there wasnt much else I could do with it and it was best moving onto a camera with better capabilities.

If you can drag any other members onto this thread, Brilliant. I think the more heads we've got talking and referring on here the better. (also applies to any lurkers who feel they have something to contribute) please step forward and give your advice.

If you have a scenario or hurdle you've recently overcome - great post it up as this might benefit myself or other enthusiasts.

I thought i mentioned this in a previous post, apologies if i have but once i have got my new laptop I plan on getting this
Air Nav Systems

So yeah. Once I have the basics of the video camera sorted. I'll continue to save for a new laptop and then the radarbox.

I finally have my videocamera!

I am now going through process of learning the recording and digital picture taking process (apparently my HDC can also take stills too)

As well as the normal videotaking process i want to be comfortable transferring data from the videocamera onto the computer, I've been given a registration card and promised if i return it to Panasonic before 31st August 2010 I will get a free 32Gig SD card. The one that comes supplied with it is 4Gig.

Once i've recorded some basics I intend to get some footage of wildlife, as well as birds sat on rooftops or if possible i'd like to get this thing mounted on a tripod and capture some aircraft flying into Manchester Airport. That should get me practiced with the basics.

Once thats done i intend to sort through the auto/manual procedures as well as familiarize myself with the many options (theres lots to go through)

And as a Bonus to me the local guy at the camera centre dropped his sale price down from the quoted £400 to £360.00 so I saved £40.00. I could of got this on Amazon a few weeks ago for cheaper but at least if i have any issues with it now I can go back and see him. Its great to have a familiar face who i can speak to locally. I'll drop by later and offer a link to some pictures of it.

Hey,
so it seems like i already have the basics and i thought i'd start with 2 simple videocamera zoom tests.
Test1

Test2

Best viewed in 720HD. I want to try and get some daytime footage of the Heron that usually pays a visit to our Garden, as well as aircraft footage too. Tomorrow I intend to get this on a Tripod to get better stability and practice with that.

Cool. Looks like there's a half-decent bit of glass hanging off the end of that thing...

Couple of points to note - like I said, the lens quality looks excellent - it will be very interesting to see how it performs at night. have you tried out the manual focus? If the MF seems hard to operate well, don't despair until you have spent a lot of time with it. The focus control on my elcheapo samsung is awful, but I have spent so much time with it, i can work it quite well now.. Practice until your fingers bleed, but make sure you bandage them well so you don't spoil the camera...

The OIS looks good too - it's fascinating watching it as it causes little jumps as it has to move the image to keep up with panning/zooming... (yes, I have no life). You might see instructions in the manual as to when to have it on or off - some cameras recommend turning the IS off when using a tripod, but even if it says that, TRY it. Different tripods will move/vibrate/flex differently, so what works for one combination may not work for another. Again, lots of tests, preferably at night after you master the basics.

I look forward to seeing how it handles low light.

I'll shut up now, and let you get back to it..

Wow thanks for the quick reply mate.
I was beginning to think that everyone had left the thread and i was talking on my own!
I have some very basic tests i want to run. I still haven't mounted this thing to a Tripod yet, i've been waiting for clear skies. In the mean time i've been taking pictures using the Tele Macro feature on the digital camera mode. (it's actually better than my Sony Cybershot)

The weather hasn't been good at all here in Manchester for about a solid month now. Every night from 11pm onwards I check the sky. I recorded this one under standard settings with Night Scene Mode Switched on.
www.youtube.com...

A couple of things. Firstly apologies for the wobble at around 1:15 I was trying to straighten the videocamera. Secondly its again not mounted to a tripod. And 3rdly the sky was patchy, hence the clouds passing every couple of seconds.

Regarding the manual options. I'm still very much in the earliest stages of trying this videocamera out, theres so much to learn about it. However the other night after filming this i took your advice regarding filming normal objects such as street lights, because i was so zoomed in on something else i panned across to the street light and it appeared to be pulsing (a trick of the sensors/camera zoom?) after a couple of seconds adjustment it came into view perfectly but it backed up what you said about lighting conditions and angles superbly.

Theres a couple of things I want to record, mostly moving and still wildlife, and also natural objects like aircraft, cars in daytime/night time as well as working through the many options available to me, like you said just to get the man hours practice in. I truely do feel though now that i've actually stepped up way past what i had before, its what i wanted and its taken me a few months to own something like this but i feel confident i have the technology, I just need the practice now to be able to use it confidently and record the best footage.

Thanks again for all the help and advice. I don't honestly think that i'd of learnt quite so much without all the help from you guys on this forum.
When i have more videos available I will update the thread accordingly and try and post up with the options/configurations I've used.

In friendship
Rich

Nice Moon video - like i said, that's a very capable lens, and the exposure choice the camera made was pretty well on the mark. Getting that good a result on the Moon on your first go is a very promising sign.

I trust you noticed that when out of focus, you got a 'squar-ish' shape - so you have a four blade aperture, giving 'quadrilateral' bokeh. If any ufo's take on a square appearance, you're probably out of focus! Note that some cameras use weird and wonderful aperture systems, so it might be worth experimenting with different light levels and different zoom settings - the shape might change, or its orientation.

The pulsing effect is quite common. These cameras all use feedback loops in both their AF systems - the focus will rack back and forth to try to get the maximum contrast - and their exposure systems. So you can end up with a 'bouncing' effect where the image not only grows and shrinks as the AF tries to nail the focus, but also goes up and down in brightness at the same time. Plus, the two are intertwined, and can actually interfere with each other, so it can be a few seconds before it stops. PLUS (as if you needed more stuff to think about!) if you are filming anything that has a frequency, eg a lot of AC streetlighting, tv screens, that frequency can cause harmonics with the shutter, so the exposure has even more trouble steadying down. Using manual focus and exposure will normally fix that....

My videocamera has this problem (as well as healthy flaring when I add a tele-extender!) and a vertical streaking issue when I shoot LED lighting, eg:
www.youtube.com...
That's NOT a UFO shooting its raygun, despite appearances...!

Anyway, keep up the good work. Just don't be too disappointed if you now find that with good gear, most ufo's may be just too easy to identify! The more you learn, the less unexplainable things are up there..

[edit on 4-8-2010 by CHRLZ]

reply to post by CHRLZ


Thank you so much. I am really pleased that as a result of me now buying this camera I now have a 2nd hurdle to overcome. It's simply practice practice practice.
A couple of videos to share with you, I finally have filmed aircraft. The footage again could be better and i'm thinking about getting a new tripod. The one i have is light and mobile but i'm not sure how good it is?

Aircraft Footage #1
This is outgoing aircraft, admittedly it caught me off guard as I was facing the other way. I swung round pretty quickly though to record it.

Aircraft Footage #2
This is inbound - A Virgin Atlantic 747 (I think). I was that close I could see everything! haha.

Ok I wanted to ask your advice about the scenes and modes I have available to me while recording. Under the main menu - recording setup. I have SCN Scene Mode. There is an option under the LCD menu and its icon is a half crescent moon and star and its called 'colour night view' and when i select this the whole of the night sky eluminates and its like shooting in night vision. The one thing i found was that shooting under this mode everything is recorded in slow motion ? ?
Is it supposed to do this? I tried a number of different things with this mode and its fantastic for seeing the night sky in (obviously because you can see more) but the fact that a fast moving object - even an aircraft, would come in on the flight path, I couldnt get it to focus properly because everything was running slo-mo. It mentioned something about the shutter speed but I wasnt sure I could alter that while shooting under this mode. I do realise it might be something i've yet to learn or maybe just dont fully understand.

Finally yes. I do realise now that alot of things I'm looking at more than ever are very mundane. For me it only heightens my awareness and improves my enthusiasm to capture something unique. At least while I am waiting I can practice with the belief that I have some awesome recording equipment and just have to learn all the features and functions.

Please respond with any advice regarding colour night view. If you want me to I can record something later with it to explain it better.

In friendship
Rich

Originally posted by Superiorraw
Ok I wanted to ask your advice about the scenes and modes I have available to me while recording. Under the main menu - recording setup. I have SCN Scene Mode. There is an option under the LCD menu and its icon is a half crescent moon and star and its called 'colour night view' and when i select this the whole of the night sky eluminates and its like shooting in night vision.

The one thing i found was that shooting under this mode everything is recorded in slow motion ?

?
Is it supposed to do this? I tried a number of different things with this mode and its fantastic for seeing the night sky in (obviously because you can see more) but the fact that a fast moving object - even an aircraft, would come in on the flight path, I couldnt get it to focus properly because everything was running slo-mo. It mentioned something about the shutter speed but I wasnt sure I could alter that while shooting under this mode. I do realise it might be something i've yet to learn or maybe just dont fully understand.

Only have time for a quick response, so i thought I would just address this.. Ok, the way night vision works on cameras varies. But it will be one or more of the following:

- the camera moves its internal IR filter out of the way - it normally sits over the sensor to protect it from the 'normal' high amount of IR (eg in daylight) - if the camera uses this method, usually the colours go 'weird', or it goes into monochrome mode. This is, if you like, 'true' night vision, and not many cameras do it any more. It's a REALLY bad idea to use this in bright conditions! In this mode, by definition, the camera is very sensitive to objects that are emitting near-IR, and red/green things will show up more brightly.

- the camera slows the shutter speed way down (and possibly the frame rate as well), so the sensor is exposed to much more light than usual. This gives the 'slow-motion', almost 'slurred' appearance, and it means individual frames are much more likely to be very blurry (motion blur). You may or may not have control over the shutter speed...

- the camera 'boosts' the sensor output electronically - this will make the image brighter, but also much more noisy/grainy. It's just like using a higher ISO setting or film speed in a still camera.

You will need to read the manual to find out what control you have - can you engage (some of the) manual controls while in night vision?

Note that apart from the IR filter thing (which I'm suspecting your camera doesn't have), night vision really is just using a bit of trickery to enhance the image - it looks like you gain a lot, but it might be a bit misleading. The added brightness comes at a huge cost in resolution and false detail and artefacts/noise. I strongly recommend you focus on using normal footage first, and only use NV when it is justified and you can afford the losses in quality.

Hope that helps, gotta run - I'll take a look at the vid's later.

The videos look very good - that was Autofocus ON, I presume? The first one looks as though it is using 'tracking' AF, as it holds the focus very well.

The lens is obviously high quality, and having that range of zoom feels good, don't it!! BTW, may I offer a small word of caution about magnification... At the extremes of the zoom range, the lens will be pushing the limits of its design, so you can expect a little softening, perhaps some CA (chromatic aberration, usually visible as blue/purple fringing around high contrast edges), maybe some vignetting (outer edges darker than the centre)... Noww that's just the start..

Add on the immense diffculty in holding the lens/camera steady, the rapid angular movement which makes it hard to track objects and keep them in frame, and then there are the inevitable atmospheric effects, haze/dust/smog/fog, thermals, 'shimmering'... Then add on the low-light levels at night...

Basically, once you get up to 15x and greater, the old 'diminishing returns' thing starts to bite.. HARD. You'll need a VERY sturdy tripod - image stabilisation only gives you about a 2-3 stop advantage (ie not as much as you might think, especially at night). Plus, going higher and higher in zoom will eventually simply get you a more blurry and unsharp result. A bit like the silly way people are endlessly zooming in on images here at ATS, and blowing them up 4, 10, 20 times... All you end up with is the shapes and artefacts created by whatever interpolating algorithm you used - ie FALSE detail.


So, what's my point? Well, I have TWO.

1. TRIPOD. Get a decent one. I'm afraid the words light and mobile and tripod do NOT go together! Now I realise you are working to a budget, but here's what you do. Whenever you see a bunch of tripods at a photography store, go and poke them and play with them. If the head is easy to flex around, try the next bigger one. At least ONCE, try a big heavy high quality tripod (Manfrotto, Gitzo, Benbo, Velbon) to find out what they feel like. Then look for something cheaper that gets close... Seriously, you won't believe the difference a good steady tripod makes. Out of interest, my favorite hiking tripod is a cheap and cheerful Optex T560 - it's big, but strappable to a backpack... It looks like it is still available - maybe give it a try if you see it. If you are serious, I would NOT get anything less than that sort of thing. It's not only pretty steady, it has a *really* good head - uses some sort of damping grease that makes it pan & tilt ever so smoooothly. Again, try panning and tilting on a quality tripod and you'll see what I mean.

In regard to tripod use:
- do not extend the legs any further than you must. The lower YOU can get - lie on the ground if you can! - the more steady your platform. NEVER, ever wind up the centre column, unless you simply want to show someone how high it can go...
- when using it, try to operate the camera controls as lightly as you can, and let go of the camera as much as possible so it remains still

By the way, have you tried a bean bag (20-30cm-ish)? A good bean bag (home built if you like) works great on car roofs, fence posts, tree branches, and is obviously much more portable. Some camera shops sell them (at ridiculous prices), but there are instructions on the web to make your own.


2. DON'T be tempted into a 'tele-extender'. Tele-extenders are add on lenses that give you, supposedly, extra magnification..! Yeah, well, they sorta do.... But they reduce your lens quality, increase all the issues above, make the camera heavier and more wobbly, all for the sake of, at best, maybe a 1.5x increase in magnification. (They might be rated 2x or 3x, but the actual increase in resolution is nothing like that.). Just remember that your lens is designed as well as it can be, There are very good reasons why your camera doesn't zoom further than it does...

I'll confess I'm being a little unkind - there are a couple of half-decent extenders out there, but if they don't optically 'gel' with your lens (and you won't know that until it's too late..), the experience will scar you and your camera for life..

I'll further admit I'm being a hypocrite - - I own a couple of t-e's!! But I normally only use them to demonstrate things to other camera owners...