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Digital photography

Started by Carole, Oct 05, 2007, 17:03:12

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Carole

I have been wanting to get into Astrophotography for some time having also been inspired by my visit to COAA and weighing things up, I think a Digital camera is the route I might go down (although not absolutely sure yet). 

I have now discovered you need an SLR camera and not the compact sort I already have.  However need some help and advice from some-one who knows what equipment etc I will need and wonder whether some-one would be willing to act as my mentor.

Not quite sure when I will be ready to purchase a camera, but as least I can be considering what to buy and looking around if I get the right advice.

Thanks
Carole

Ian

well yes, and no. If you're interested in starting out, you can use a compact camera to take photos of the moon through an eyepiece. That at least would start you off on the slippery slope toward shouting obscenities at anyone with laser pointer at DSC.

However, as you can see from Johns images from the last DSC a digital SLR can give some excellent results. However, it would be worth investigating if it's possible to connect an SLR, which is a bulky camera, to a relatively small scope. IIRC you have an ETX?

mickw

#2
Carole I agree with Ian.
Firstly you can attach an SLR to the ETX although the weight might cause some balance issues and it may require some sort of counterbalance (should be simple to sort out though).  However if attached at the rear you would be restricted to subjects nearer to the horizon, with an SLR attached you would not be able to raise the scope much more than 40 degrees from horizontal.  Or you could use a 1.25" eyepiece adapter and have the camera mounted in the eyepiece holder which would give more flexibility.
Telescope House sell a Universal Digiscope Adapter for £40, it clamps round your eyepiece and you attach your compact camera to it - I have just got one.
If you are observing on the 9th, I'll be glad to bring it along.
I have not got a clue about astro imaging except for what I've read here, hopefully, this setup will give me some insight into what is required and was is possible.
Good luck,
Mick
Growing Old is mandatory - Growing Up is optional

Mike

I think the problem would be in the scope mount. The ETX mount is nowhere even close to being good enough for long exposures. However, it would be good enough for shots of the moon and planets and for that a simple webcam would suffice.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Carole

Thanks for all that advice every-one. 

I am hoping to get along for 9th, if not 13th.

Two comments here.  Firstly I am sure the ETX has an alternative "camera port" at the end. Plus the usual port (where the eyepiece goes is on the top, not at the end so I can't see the camera causing an obstruction if that is what you meant.  Plus I was expecting to use a counterweight.

Mike, I was only intending to do exposures for the sort of length of time we did in COAA which were upto 2 minutes and the results were very pleasing, or was this because the skies were good there?  Will the ETX not be good enough for that?

Other alternative is to get a webcam but I don't have a laptop, or at least I have been offered one but the battery life would not last for more than an hour.  Plus would need lots of advice on what else I will need to go with this and how to do it and are you all willing to do this?
I thought a camera might be more straight forward and I would need less advice once I had bought the correct equipment.


Carole



Mike

Quote from: Carolepope on Oct 08, 2007, 13:02:16Mike, I was only intending to do exposures for the sort of length of time we did in COAA which were upto 2 minutes and the results were very pleasing, or was this because the skies were good there?  Will the ETX not be good enough for that?

Remember that you are talking about 2 minute exposures on a substantially more capable mount than the ETX mount, plus I think you did manual guiding at COAA if I am right? The 2 fork mounts at COAA were very accurate and stable and the smaller (Gemini?) mounts are also very capable mounts. Two minutes might not seem like a long time, but an errors in your mounts drive system within those two minutes, which is probably around the cycle length of the worm, will produce out of shape stars.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Ian

well there'll be no shortage of advice ;)

I don't usually manage to get to imaging sessions, but certainly at DSC there's scope (pardon the pun) for us to try various means of getting you imaging. There's quite a learning curve, as you're finding, as well as some basic investments. I have webcams you could borrow (obviously if you can get access to a laptop...)

Even using the camera port on the back of the scope (I don't think you'll reach focus using the eyepiece "hole"), I would be concerned that the camera would stop the scope rising much above the horizon. I would enlist the help of someone with DSLR to answer this question once and for all. Also, do you use a wedge? It would help with that by raising the scope up, and it also removes field rotation. This is an effect you'll see quite quickly using an alt-az mount.

Understanding what your current equipment is capable of is a massive first step.

Question for anyone else: is anyone else imaging using an ETX? I think Carole could do with talking with you...

Rocket Pooch

Not me boss, I sold my ETX because it was not good enough for DSO's ok for web cam imaging though.

Carol, the key thing here is expense, the amount you are willing to spend will have a direct effect on the type of kit and pictures you will end up with.

Personally if I we're to do it all again I would start with a SLR and tracker mount for wide field images, but that's only going to work well at DSC.  But even then you will be spending £500+ minimum to get any good pictures, and a whole lot more to get great ones.  In fact I'm positive if some of our other halves knew how much we had actually spent on the hobby, it would have the same effect as them finding out we slept with another person on a sofa, if you know what I mean  :o

If you want to do planetary, get a web cam your scope will be fine but don't expect hubble type images.

As for mentoring, this is an extremely patient taxing hobby, akin to discussing the rights of free speech to Lenin.  I'm not sure any of us have enough time to become a "mentor", what you need is the sheer determination of Fay, a few bob (money not men), beer, wine, more beer and a deep pockets (more money) that should get you through the 1st 3 months, then it get difficult and everything goes wrong just as you think you are getting the hang of it.  And then it rains a lot.  Having said that it is kinda cool when it works.

I think I speak for all of us here when I say the best thing to do is get a book 1st and start from there.  Decide what you are going to image and then research the subject before you start.  Use the yahoo groups and also UKAstroImaging web site, loads of help there from people who do not seem to work and therefore can offer advice.

Also Ian King runs imaging courses, you might want to get onto one of those!

Chris

JohnP

I would like to ditto Chris's comments & also add that 2mins might not sound a lot but when you have to track something with sub-pixel accuracy for this length of time believe me it is... took me about 3 years & a couple of grand before I got there....

You will also need some form of PC or laptop for post processing at the bare minimum plus all the s/w that goes with it.... Just ask Fay... :-)

John.

Carole

Hmmm, Well I understood some of all that, thanks guys for all the advice.  If I've understood right the tracking on the ETX is not good enough for long exposures.

The idea of a loan of a web cam for practice before I lay out money on something I might not get to grips with, sounds a good idea.  I could use the lap top I have been offered for trying out purposes.  then If I find I want to continue I can purchase my own.

Many thanks we'll talk further.

Carole


Mike

I would highly recommend you buy the excellent book - "The New CCD Astronomy by Ron Wodaski".
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Delphine

Hi Carole

I am reading 'Lundar and Planetary Webcam  User's Guide' by Martin Mobberley.  It is aimed at absolute beginners and I am finding it very informative.   Among other things it tells you what type of equipment you need for the type of imaging you are going to do and why.  In other words my scope and mount would only cope with a webcam and lunar and planetary imaging!  Also explains the stacking software.

Delphine [the one that looks like an observatory!]

Mike

This thread has gone off topic again !   :twisted:
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Carole

Yes, but keep going, I might beat Fay's record for the most replied to posting.

Delphine that book you recommended sounds good for a beginner so will put it on my Christmas list if I haven't bought it before.

Thanks
Carole


Fay

Carole,

your best bet would be to learn from Delphine, Jim &  Miriam, as they are just on that first rung of the ladder.
You like the planets & Moon more than deep sky so, I think what you will need to start is:

A decent, reliable laptop with at least a 3 hour battery life & 4 USB2 ports.
A webcam, with correct cables, filter & connector which is for planets & Moon.

Preferably a better telescope, but perhaps yours will be ok for the above.

K3CCD capturing programme, about £25.

Registax (free) stacking program.

Once you go into long exposures & guiding, it is a different ballgame, that I feel you may not want to get into.

Fay



It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!