Imaging Question (s) Newbie,,,

[wobbly]

Thought I would post in here rather than dive straight into the Astro Imaging Section

Have a 6" Achromatic Refractor D=150 F=750

Canon EOS 350D

Canon EOS T2 Adaptor just arrived today

Had a play around, T2 fits the Canon fine and also then attached the Canon to the Scope, can attach either direct into 2" Focal Tube or 2" Star Diagonal with other 'adaptors' I have

What do I do next:confused:

Really just wondered if there is a 'Dummys Guide' on this Forum anywhere or info on a Web Site I can read up on?

[roundycat]

start by taking small steps. Stick the camera into the back of the scope without the diagonal (usually only for visual) and see if you can focus the whole shebang on a distant tree or chimney. If you can get focus on something 1-200 yards away you are close enough to infinity focus for you to be able to focus roughly on a star field and then do it accurately. Trial and error most like.

You don't say anything about your mount for the scope, assuming you are able to track then start taking 60s exposures and experiment from there. Learning to focus will take some time.

Dennis

[barx1963]

Hi Wobbly

I am not much further advanced in the imaging game than where you are, but I can offer some insight. Focusing is the #1 problem to be tackled at this early stage. I found a hint in a book that I have been using successfully.

First get focus as best you can with the viewfinder or if you Canon has Liveview use that. This will probably only give you a rough focus. Then snap of a shirt exposure of a brightish star. It needs to be bright enough that you can just see it in the viewfinder.

Then review the shot on the LCD of your camera. Zoom in on the star in the review. You will see in the bottom right corner a little graphic showing the area that is being zoomed in realtion to the full image. When the picture of the star is as close in size to the dot in the middle of the graphic when at full zoom, your focus is about as good as can be.

Don't use really bright stars as they make quite large images even at good focus. I have found I can acheive pretty good focus even with my dodgy little scope in about 5 minutes if I am patient and have done it in only 3-4 shots at times

Hope this helps!

[wobbly]

Thanks for both replies, reason I asked the question was because I couldnt focus and wondered if if I needed an eyepiece inserting in the 2" dovetail which the EOS T2 adaptor screws to?

Canon 350D does not have live view so its via camera eyepiece only

Will try the tip about about practising focusing during day on a distant tree or something and take it from there

Scope is a Helios 6" refractor on a CG5 (same as EQ5) Mount (manual)

Will fathom it eventually probably via trial and error, dont really understand the Canon 350D fully yet as only recently bought it for using on my scope, used an SLR decades ago but been digi point and shoot since then:confused:

Maybe my main problem has been attaching camera to the 2" Star Diagonal for ease of use in looking through camera eyepiece

[jgs001]

I've found with both my refractors that I could not get focus without some form of extension tube. The ST80 was nowhere near. The C80ED was damn close attaching the T thread to the provided fitting, but just not quite there.

I've not tried manual tracking, but it doesn't sound like much fun to me, not without all sorts of added things which may end up costing more than the motors.

[barx1963]

Yeah I would guess that the Diagonal will make things a bit harder. I have found Michael covingtons book on DSLR Astrophotography very helpful in getting setup right. Also practicing finding those little buttons on the camera in the dark is very helpful!

[Jarndyce]

For focusing, get yourself or build yourself a Bahtinov mask.

http://stargazerslounge.com/showthread.php?t=75177&highlight=bahtinov

Mine works really well.

They make focusing through a DSLR a breeze.

Psychobilly has also been investigating producing them commercially, so if you can't make one, check out his thread.

I wouldn't advise hooking up to a diagonal. Instead, plug your DSLR into a laptop to view the image to see if it's in focus. I believe software is supplied with the Canons.

I too am just beginning at this. Lots to learn and great fun!

[wobbly]

I've found with both my refractors that I could not get focus without some form of extension tube. The ST80 was nowhere near. The C80ED was damn close attaching the T thread to the provided fitting, but just not quite there.

I've not tried manual tracking, but it doesn't sound like much fun to me, not without all sorts of added things which may end up costing more than the motors.

Just had a play around with the scope on both a tree around 500yds away and some houses on the horizon around around a mile away, just not quite enough length to focus in so need an extender:icon_scratch:

Hopefully will get it sorted, eventually!

[jgs001]

If the drawtube was all the way out, something like this I went for the 50mm version.

[Psychobilly]

Put thre diagonal in for now that will give you the extra "length" annd should allow the extra travel that you need... remember to wrap the strap of the camera round the tripod...incase the diagonal falls out of the focusser... and the camera heads to the deck....

Billy...

[wobbly]

Put thre diagonal in for now that will give you the extra "length" annd should allow the extra travel that you need... remember to wrap the strap of the camera round the tripod...incase the diagonal falls out of the focusser... and the camera heads to the deck....

Billy...

I thought that too and tried it (2" Star Diagonal) couldnt see anything at all, day or night and spent ages trying to focus in, have now ordered an extender

Thanks again for all your help, really want to get this all sorted before all my gear heads off to Spain in a couple of weeks by car for the summer:glasses1: