Castor

[wxsatuser]

Last night I messed about doing movies of the moon.

After finishing with the moon I had a go at Castor.

Set up

SW 80ED Pro......Hyperion Zoom 24mm.......Canon 60Da......Movie crop mode.

About a minute at 60fps aligned and stacked in Autostakkert.

[alan potts]

Very nice, I thought the two parts of Castor were more equally matched than the shot shows.

Alan

[lunator]

Hi nice pic,

I have to agree with Alan, the components seem a little far apart and too uneven.

What magnification does your set up give?

Cheer

Ian

[wxsatuser]

Hi Guys.

Could have sworn I was on it.

I have'nt measured the exact distance from EP to sensor but I would think it is at least 60mm.

My calculations with 24mm EP puts the ratio at F11 and magnifacation over prime is 1.5.

Does that help.

[Stu]

It is interesting. I agree with the others that visually they look much more similar in brightness, and quite close together. Just check on SkySafari though and one is mag 1.6, the other b component is 2.9, so this is probably plenty to show up photographically?

Will have a closer look next time.

Stu

[wxsatuser]

Have to wait for the rain and cloud to go away to check.

[Moonshane]

I think you had it. the components do seem slightly different in size to me but I have never noticed colour. all the online images match yours quite well e.g. http://doublestarobserver.com/springtour.html

http://www.backyard-astro.com/deepsky/041209/ds.html

I suspect we'll all be looking a bit more closely next time out. I have seen them at this sort of separation at extremely high power (500x or more).

[lunator]

That's the beauty of doubles they always keep you guessing

Not sure how to calculate the magnification on your set up but Moonshane could onto something with the very high mag. View.

Cheers

Ian

[chiltonstar]

I use Castor as a setting-up test fairly often. To me, this image is about how I see it in my Orion ED80 in terms of the relative brightness (I normally see the disks as about 60:40 size/brightness ratio), and the separation. I would expect to see them both fairly "white" though, and as sharper disks with diffraction rings when the seeing is good and I've found that elusive pin-sharp focus point....

Chris

[Moonshane]

I also use Castor to check focus when looking for e.g. the pup as getting sharp focus off sirius can be challenging! still not seen the pup yet though.

[wxsatuser]

I use Castor as a setting-up test fairly often. To me, this image is about how I see it in my Orion ED80 in terms of the relative brightness (I normally see the disks as about 60:40 size/brightness ratio), and the separation. I would expect to see them both fairly "white" though, and as sharper disks with diffraction rings when the seeing is good and I've found that elusive pin-sharp focus point....

Chris

Must admit I did the focus by eye but the image was jumping about all over the place, there was thin high cloud, seeing not to good.

I think they are not white because I did'nt bother changing camera settings from the Jupiter run.

[Tinker1947]

I put a Celsetron 6.3f FR on the C11, spaced at around 103mm so this is a image of Castor 30 seconds @ iso800, Focal Length 1764mm

[Moonshane]

I have just had a look and see them as slightly different sizes and with one slightly dimmer/dirtier white than the other so matches the image of the OP well.

[Tinker1947]

My image is a bit blown due to the 30 second timing, it is mostly testing the Focal Reducer.......this other image is the 1100D attached to a Hyperion 13mm, 20 seconds @ 800 ISO, Focal Length 1764, it shows the colour of the other star better but hasn't had any processing.

[wxsatuser]

Had another go Sunday evening.

Think I pushed the limit of this setup.

Had the zoom on 8mm and added a 40mm extension between camera and EP.

Seeing was very poor there was lots of cloud and I had smoke from a fire drifting across.

The colour is not good....the image is full size, the result of a stack from Autostakkert.

I now know for sure this is Castor as I took a still at normal resolution and all the stars line up.

[todd8137]

Great double looks good to me

Pat

[ely_ellis]

Another one I haven't got around to doing.

Nice split Mike

Martin