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New kit

Started by Carole, Feb 08, 2009, 23:32:37

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Carole

I thought I had better start a new thread.
Thanks to Robert's suggestion and getting advice from others I have today purchased the following as the first step towards getting into Deep Sky Imaging.

WO Megrez 72 APO, excellent condition.
CG5 GT mount, excellent condition.
WO Vixen-style dovetail plate (G-VP), excellent condition
WO 2" extender tube (WE-EX2, excellent condition
WO 0.8x reducer/field flattener V.III, excellent condition
Tele Vue 5x Powermate, excellent condition
Philips Toucam (PCVC840K/20), as new - (will probably re-sell this).
Kood EOS adapter
WO 1.25" dielectric

I have been picking the brains of a lot of people to make sure I buy the right thing.
Now I have to learn to use it!!!!!!!!

Have also been having lots of discussions with Mark, Daniel and people like Nick Syzmanek and Ian King at Astrofest and I am weighing up dedicated CCD imaging v DSLR.  Currently the DSLR seems to be winning both on cost and ease of use.  I am aware there are some limitations.

Would welcome further comments while I am still making up my mind.

Thanks
Carole

JohnP

Carole,

As a start I would say DSLR imaging is probably easier & more satisfying - I would say you can't beat one shot colour & you will certainly have to get to grips with all the basics such as polar alignment, guiding, flats, focussing, processing etc. & these will be invaluable regardless what you end up doing. The WO 72 & the .8X field flattener you have will be ideal for this type of imaging & should make many wide field DSO's readily available. You may well have to consider removing the IR filter from the camera at a later stage as you advance to more tricky objects.

John

Carole

Thanks John, you are confirming my thoughts on the matter.

Yes I was aware about modifying the DSLR to remove the IR filter and I have information on places who can do this. 

Carole

doug


     Well done, Carole!!  We are looking forward to seeing some of your images on the Forum in the future.  Does this mean you are going to be a "new kid on the block" and wow us with superb imagery soon?? :)
Always look on the bright side of life ...

Mike

A few things to bear in mind with a DSLR :-

They are not cooled and therefore images will be noiser, especially in warmer weather.
They have a huge FOV and therefore small objects like galaxies and planetary nebula will be limited.
They are colour and therefore you are restricted with what you can do regarding narrowband imaging.

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 Mike,

Yes I have been told these disadvantages by others as well, however seeing some of the wonderful images being produced by others with DSLR and because I am feeling a bit daunted about using a dedicated CCD camera and all the paraphenalia and processes that go with it (also the cost of a decent one) I feel this is probably as much as I can cope with at this stage.

QuoteThey are not cooled
I have actually seen a cooled DSLR for sale on the internet, but it was about £1200. 

QuoteThey have a huge FOV and therefore small objects like galaxies and planetary nebula will be limited.
will the 5 x powermate help with this?

Carole

Carole

Hi Doug,

QuoteWe are looking forward to seeing some of your images on the Forum in the future.  Does this mean you are going to be a "new kid on the block" and wow us with superb imagery soon??
I don't know about "soon" but hopefully over the next few months.
Quotesuperb imagery
If only!!!!

Need to learn to use the scope first. 
Then actually buy the camera etc.

However we do have some superb imagers in the society who are only too happy to help and encourage learners like myself, so I think the word "eventually" might be more appropriate.

Carole






MarkS

Quote from: Mike
They have a huge FOV and therefore small objects like galaxies and planetary nebula will be limited.

Mike, 

I'm not sure I understand that comment.  The CCD pixel size of a DSLR is approximately the same as most astronomical CCDs  so a galaxy or nebula whose image is 500 pixels wide on an astronomical CCD will also be 500 pixels wide on a DSLR.  But the DSLR will also show a lot more of the surrounding area because a DSLR generally has many more pixels.

My own viewpoint is as follows:

Advantages of DSLR:
* Colour images without the expense and hassle of a filter wheel and filters
* Huge number of pixels and a wide FOV for a reasonable price

Disadvantages of DSLR:
* Since every pixel is coloured, it lacks the sensitivity of dedicated mono CCD - hence not so good for very faint galaxies
* No CCD cooling - so deep sky images will have a noisier background in warm weather
* Needs modding to improve H-alpha response
* Mechanical shutter causes vibrations and therefore blur when photographing moon/planets

Ultimately, a dedicated astro-CCD will always win out in terms of outright performance.  But I would argue that DSLRs offer both ease of use and an excellent performance/price ratio.  And, as Daniel can confirm, they can win you "Image of the Month"!

Mark

JohnP

Yep - agree with Mark - If for example you want to image a galaxy & it only takes up 500 pixels - just crop to say 1000 square & display at that.. You have so many pixels to play with with a DSLR.

Carole - I think you may be beter off going with a longer focal length scope rather then trying a X5 barlow... With my very limited experience using a dslr I had no joy using one with a barlow unless you are going for planetary/ lunar or of course the ISS :-) (i.e. very bright objects).

John

Carole

I have spent the last few days reading the manual for the new Mount and I can already see lots of advantages over the Autostar on the ETX, and that's just with reading it. 

Got really enthused tonight as the weather started off fairly clear, got the scope set up and went back to sort out my K3 which I hadn't used since I registered it and had to re-download it because I had not entered the key before it had expired.  By the time I had done that it had clouded over.

I did however managed to see Venus as a crescent before it clouded over.

If I come to DSC (which I am hoping to provided it is not freezing or hopelessly muddy) I shall just bring my new kit with me.

Carole


Carole

Have now got myself a small camera thanks to Chris's tip off (on Duncan's thread Modyfying my webcam)
http://www.astrobuysell.com/uk/propview.php?view=23217

It's a small chip, but as it was only £120 + postage, I thought it would start me off and I can use it for a Guide camera later with either a DSLR or larger chip dedicated CCD camera.  I'll see how I get on.

So with a bit of luck I have enough equipment now to do some unguided imaging, just need to learn how to do it all now!!!

Carole