CraigFair Loc: Santa Maria, CA.

I want to shoot Andromeda Galaxy, Lagoon Nebula etc that won't fit into the FOV.
I have 2 Focal Reducers and would like an opinion on which would be the better of the 2.
#1 Meade 4000 f/6.3 Focal Reducer/ Field Flattener.
#2 Celestron f/6.3 Reducer/Flatener
If there is a better one out there I would entertain suggestions.

SonnyE Loc: Communist California, USA

I have no idea. But I'll watch to see what crops up.
Are they stack-able? :?:

Albuqshutterbug Loc: Albuquerque NM

I have your number two and (Sonny don't even go there) I have problems achieving focus without an extension tube. I have tried with and without a diagonal but I wind up using a Barlow which sort of defeats the purpose.
Let me know what you come up with. And good luck. ;)

SonnyE Loc: Communist California, USA

Well, you could have said:
"I have a Celestron f/6.3 Reducer/Flatener."

And it would have taken less room, and not implied you play with Craig's #2...

Are you full of Balloon contents? :lol: :lol: :lol:

Have either of you used one of your Reducer/Flatteners when viewing or photographing nearer objects like the Moon?
I'm curious because I get about 1/3rd of the moon in my telescope.
(Which is no surprise to me.)

CraigFair Loc: Santa Maria, CA.

Hi Sonny, I have no idea if you could stack them but I don't think you would have a useable image.
Your 2/3rds image problem would be the perfect application for a Focal Reducer.
Craig

SonnyE Loc: Communist California, USA

If I had two, I think I'd try it. ;) Just to experiment...
I have learned where stacking filters is possible.
And I have stacked Barlow's with varying degrees of successes.
I just haven't gotten to a point of wanting a focal reducer bad enough yet.

CraigFair Loc: Santa Maria, CA.

You will Sonny.
Craig

dlmorris Loc: Loma Linda, Ca

Not sure if you can stack them, but if you are asking which is better, I suspect they are very similar, but one says "Celestron" the other, with maybe some cosmetic differences, says "Meade". I wouldn't worry about it. I also think that for Andromada just a good telephoto would be better. My best shot is using the Orion 80 ED, I think it is. I'll post an example.

Orion 80 ED, 600mm focal length

JimH123 Loc: Morgan Hill, CA

I don't think there is much difference between the two, and I don't know if one is better than the other. The field flatener portion of it is going to impact the stars farther from the center. The flat surface of the diagonal tends to cause the edges of the image to distort and this is what is corrected. It also reduces the focal length allowing a wider field of view.

If I were to guess at what is going to happen if you were to use two of them stacked is that:

1) You would probably introduce a lot of vignetting.

2) The edges would be over corrected and introduce a whole new level of distortion.

DLMORRIS also responded in this thread to use a camera lens for Andromeda and I agree. This galaxy is quite large and just doesn't fit into the field of view of these longer focal length scopes.

Andromeda is an object that the center is bright enough that you can over expose. So you need to be mindful of the amount of exposure time you use. The outer edges are also quite dim. So you need multiple exposures to bring out the edges, but also short enough that the center is not blown out. And this might be a good case to prepare two images - one exposed for the center and one exposed for the edges and to overlay them in Photoshop with the overexposed center one on top, and to align and carefully erase the center from the top image exposing the properly exposed one underneath. And be sure to feather the edges of the eraser quite a bit.

CraigFair Loc: Santa Maria, CA.

What a beautiful shot of the M31 Andromeda Galaxy.
DL thank you for your help as I expected the two are so similar it probably makes no difference. I think stacking is Sonny's idea of being silly.
Your idea of using a wider FOV scope does make a lot of sense. I have a Celestron 104mm that might work pretty well.
Craig

CraigFair Loc: Santa Maria, CA.

Jim H thank you for all the info too but particularly the advice about stacking in PS. I have yet to master anything in Photoshop.
Craig

Tom--K4TTA Loc: Near Memphis. TN

I have a Celestron CPC1100 11" SCT with a 2800mm focal length. Also have the Celestron F 6.3 Focal Reducer. Please note the Celestron F/R lens are NOT sealed and I have encountered dew/fogging problems when using it. (We have HORRIBLE humidity here in "Elvis Country"!)Otherwise, it's a great accessory. I've not seen the Meade F/R - so no opinion. Hope this helps.

Tom Richardson, K4TTA
Vice-President for Programs
Outreach Committee Chairman
Memphis Astronomical Society
www.memphisastro.org

CraigFair Loc: Santa Maria, CA.

Thank you very much Tom, I've got the Celestron F/R mounted for tonight.
Clouds willing I hope to get some shoots of Andromeda.
A fair amount of light pollution so we'll see.
Craig

Tom--K4TTA Loc: Near Memphis. TN

Please let me know how it works out.

Good Luck!
Tom