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iceman
25-08-2007, 07:09 PM
Hi all

Got the 12" dob out in-between the clouds tonight, to practise the afocal shots for Tuesday's eclipse.

I'm borrowing RB's Canon 300D, and used my 28mm f/2.8 lens on it, afocally (handheld) shooting through a (borrowed, thanks stringscope) Parks 30mm eyepiece.

Settings: ISO400, 1/640s exposure, f/4.0, 28mm focal length.

The bottom half is sharp, but the top half is not. I need to see if it's due to being at the edge of the eyepiece, or edge of the lens.

Not the best method to get completely sharp images during the eclipse, but you have to work with the equipment you've got (or are borrowing :)).

I didn't convert this to greyscale, because obviously there'll be shots when the Moon is red on Tuesday night. I need to check the white balance though, the 300D made these come out with a very yellow/green tint which I tried to remove some of during processing.

Only other processing was resize, levels and USM.

Thanks for looking.

Dennis
25-08-2007, 07:38 PM
Hi Mike

Why afocal? I’d have thought prime focus would have been better:

More rigid connection - DSLR to focuser via adapter.
Easier to focus.
Easier to compose and frame.
Sufficient image scale.
Etc, etc

Assuming the 12" dob is mounted on the EQ6, that is?

Cheers

Dennis

acropolite
25-08-2007, 07:43 PM
Mike, you are probably already aware but if if you shoot RAW then WB can be adjusted to your preferences (WB is not aplied to RAW).

Astroman
25-08-2007, 07:51 PM
I would say go prime that way all your images are guaranteed to be of a similar size. As phil said, shoot RAW, gives you the chance to make the moon colour correct and other settings too.

Great effort though, looks natural enough.. did you also crop it?

joshman
25-08-2007, 08:43 PM
i am loving that photo, makes me wish i had a telescope. i was also out taking some happy snaps of Le' Moone' this fine eve. got my results in a thread (http://www.iceinspace.com.au/forum/showthread.php?t=23255) too.

h0ughy
25-08-2007, 11:54 PM
Gee RB parted with his 300D??? lets see that leaves him with the 5D - 2 20Da's and a 20D - he might be a bit short on:whistle:
:whistle:

could be the scope moved when you took it too mike? going back to the days of setting up a tripod looking through the eyepiece???;)

[1ponders]
26-08-2007, 12:08 AM
It would be a tight squeeze with the 300D and 1500 FL. That is assuming Mike has the adapter to go for PF

iceman
26-08-2007, 07:07 AM
Hi Dennis, you're right - I'd prefer to go prime focus. However, my 12" newt isn't setup for prime focus.
a) I don't have the adapters to set the camera in the focuser
b) It won't come to focus without getting a low profile focuser or moving the mirror up the tube

It literally was mounted on the dob mount, not the EQ6. I won't be taking the EQ6 with me - it's too heavy, needs power and the eyepiece ends up in weird positions. I'll just be doing the dob mount thing.



I did take them in RAW, but forgot to manipulate the WB in RawShooterPremium. Thanks for the reminder.
It's only cropped on the sides, the moon practically fills the frame (vertically) with the 28mm lens and 30mm eyepiece.


hehe I considered it. The exposure is short enough that there shouldn't have been any hand-shake/wobble.


It's tight with the 28mm and afocal. The full moon will only just fit.
I've got the 17-70mm sigma lens, but that's not a good afocal lens (too much vignetting), and I'll be using that lens on my 350D for the widefield shots.

I'll take my laptop with me so I can download them onto the laptop and check them out as I go, and re-shoot if necessary.

Dennis
26-08-2007, 07:47 AM
Hi Mike

Have a look at the Baader range of Rings that can couple the thread on a DSLR lens (where the UV filter normally screws on – 58mm for my Pentax *ist DS Sigma 18-50mm kit lens) to the thread of an eyepiece if the eyepiece has a thread at the eye lens end.

Have a look at the Alpine Astro (http://alpineastro.com/digital_photography/digital_photography.htm)page for the Baader Hyperion Digital T-Rings which enable you to couple practically any camera made directly to the 54mm thread of the Hyperion Eyepieces.

Of course, you would need to get your hands on a Hyperion eyepiece or have a compatible thread on another of your eyepieces.

Cheers

Dennis

[1ponders]
26-08-2007, 10:03 AM
See h0ughy of course :P

Dennis
26-08-2007, 10:42 AM
Nahh, H0uhgy doesn’t stoop below the prime cut off line of Nagler and Pentax eyepieces. Hyperion’s wouldn’t even register a blip on his over-the-horizon equipment seeking radar.:whistle::whistle:

Cheers

Dennis

[1ponders]
26-08-2007, 10:47 AM
:lol:

RB
26-08-2007, 10:51 AM
:lol:

Of course you're talking about anther David Hough, the one that doesn't have his wife's friend reading the threads on IIS ;) ........:rofl:

h0ughy
26-08-2007, 02:08 PM
Oh you guys are cruel

OK I have a scopetronix 40mm EP with camera thread for T ring and a scopetronix max view thingy 2" to take projection pictures, just screw on your tring and add the camera. If you want to try it then drive up and have a go Mike - bring the scope. Alan Meehan has a hyperion.

[1ponders]
26-08-2007, 02:11 PM
Haha, told ya you could get one through h0ughy :P