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How to fit a LP filter with a SW reducer/flattener


Spikey

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Perhaps I can't see the wood for the trees here.

I am trying to fit my SW 2" LP filter into the train of my ED80 Pro with a newly acquired SW focal reducer/flattener attached and then onto a Canon 1000D.

Whilst I wait for the delivery of an M48 adapter I've noticed that the existing 2" Canon T-ring and adapter will screw onto the focal reducer.

I can't see where the LP filter will screw in anywhere obvious, am I missing something or is it not possible?

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Thanks for the reply Brant, just had look and the filter screws on OK by a couple of turns. The problem is that I think the camera will now screw onto the filter and only hang on by the filter plus a couple of turns. Not sure if I'm confident about hanging it off that way.

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I have exactly the same setup. The filter fits in-line and the whole thing does screw up tight.. check your threads as I seem to remember more than a couple of turns. Mines been in that config since April I think and hasn't moved.

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Apologies, I don't want to derail your thread Spikey, I just have a quick question: Would a normal SW LP filter work effectively in the optical train with a DSLR? Would be a lot cheaper than a CLS clip filter :rolleyes:.

I think it depends on what the LP source is. It works pretty well for me as most of my LP is still the older sodium type.. any left easily delt with in PS. I havn't tried any others though but considering the price difference as yet I haven't felt the need. (That may well change when I go to an astro CCD and longer exposures) Cheap enough to try first in my opinion & made a big difference to using nothing.

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I think it depends on what the LP source is. It works pretty well for me as most of my LP is still the older sodium type.. any left easily delt with in PS. I havn't tried any others though but considering the price difference as yet I haven't felt the need. (That may well change when I go to an astro CCD and longer exposures) Cheap enough to try first in my opinion & made a big difference to using nothing.

Yeah, my LP is mostly sodium as well. So it sounds like a pretty good idea, to start off with anyway ;). TBH, it never even occured to me before, so I think I'll defo give it a go :o.

Sorry Spikey, I'll leave your thread now! :rolleyes:

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Don't worry Andy it's the SW LP filter I was having problems with on the reducer.

I did a comparison without it fitted and with it fitted on some 10 min subs here http://stargazerslounge.com/imaging-image-processing-help-techniques/157668-sub-comparison-sw-lp-filter.html

I've got it fitted in the train now, so thanks to all, it just seemed a little weird having it form a link between the camera and reducer. It feels pretty tight though.

I'll still drop a few pics on this thread just in case anyone else is ever unsure.

Thanks

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"it just seemed a little weird having it form a link between the camera and reducer", still doesn't sound right. Have you got a pic of the setup. As said ^^^^ the filter usually goes at the other end of the reducer to the camera, not in between.

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I have mine between reducer and camera (CCD). I dont use the adaptor shown in the link above, I screw the reducer directly onto the focus tube. So I have Focus Tube - Reducer/flattener - M48 to T reducer - LP filter - Spacer - CCD.

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No I don't have the FLO adapter, will I be able to achieve focus with what I have below??

I've not had a clear night to be able to try anything out since I got the reducer.

Also I finally got round to taking some pictures and thankyou for the responses and dicussion so far.

The M48 adapter has the correct thread to accept a 2" filter so the items in connection order to the camera are as follows;

So, initially I attach the LP filter to the M48 as follows;

then the thread from the filter screws into the reducer;

Finally it's screwed onto the scope and the camera is then locked onto the M48. I then mess about with the locking ring and reducer a little to get the camera oriented the way I like it.

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Spikey, have you been able to try this out and take any test pics? I have the same setup now (my 2" SW LP filter arrived this morning - thankyou FLO! :rolleyes:).

The filter will fit between the SW reducer and M48 DSLR adapter, but there is no way it'll fit at the other end. But, this would seem to break the 55mm spacing requirement. I haven't had a chance yet to try this out with test pictures, have you been able to reach focus with this arrangement?

Also does anyone know if the FLO adapter First Light Optics - FLO Adapter for Skywatcher Focal Reducers would be beneficial here?

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I dont think that will work...the reducer is designed just to have the adaptor fitted to it for correct spacing...with the LP filter you will be to long.

No I don't have the FLO adapter, will I be able to achieve focus with what I have below??

I've not had a clear night to be able to try anything out since I got the reducer.

Also I finally got round to taking some pictures and thankyou for the responses and dicussion so far.

The M48 adapter has the correct thread to accept a 2" filter so the items in connection order to the camera are as follows;

[ATTACH]70552[/ATTACH]

So, initially I attach the LP filter to the M48 as follows;

[ATTACH]70553[/ATTACH]

then the thread from the filter screws into the reducer;

[ATTACH]70554[/ATTACH]

Finally it's screwed onto the scope and the camera is then locked onto the M48. I then mess about with the locking ring and reducer a little to get the camera oriented the way I like it.

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