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View Full Version here: : Ha and ERF combination advice sought


MLyons
21-09-2011, 02:08 AM
Alrighty then folks, I'm looking to get some ideas of what, where, how and why regarding selection of ERF and Ha filter combinations.

Let me paint the picture. I have acquired the following bunch of bits:

1 x Thousand Oaks Ha filter unit (tunable)
1 x Lumicon Ha filter unit (also tunable)
2 x 77mm diameter Lumicon Energy Reducing Filters (deep red filter in a threaded ring) with additional glass filter attached in its own threaded ring (assume UV/IR)
1 x Coronado Solarmax 40 with T-Max, BF10 blocking filter and Cemax 25mm eyepiece.

Now........the questions:

What would you do with all the bits?
What would be best to keep?
How would be the best to configure it? Red filter first, then UV/IR filter or other way around?
Is it a UV/IR filter or simply a piece of protective glass?

I have a host of scopes I could make off-axis masks for and also I'm not averse to aquiring a suitable refractor if it would be of benefit.

Any insights from the solar experts will be gratefully accepted.

Regards
Martin

sheeny
21-09-2011, 07:10 PM
The SM40 Tmax and BF10 are about all I'm familiar with. You will get excellent results with these through a small refractor like and ED80. Just check the required focal length for the BF10, but it sounds ideal for your 6" skywatcher.

Al.

OICURMT
21-09-2011, 08:56 PM
I predict Merlin will be posting soon ... :P

MLyons
21-09-2011, 09:25 PM
Thanks for the reply Al.

I was thinking of using the Stellarvue 80mm refractor that I have mounted piggyback on my main scope.
Maybe with a barlow to get the longer f ratio (apparently this system likes f15 or longer :shrug:)

I have also just acquired a 10"LX200GPS with all the bells and whistles.
This has a few Kendrick focus masks that have had glass solar filter fitted as well as threaded inserts for the various solar front ends.....

Going to be fun playing with all the new toys.......

Wife reckons I've lost it :eyepop::eyepop::screwy::screwy:

Now all I need is an 8" and 12" and I'll have the whole range :rofl::help::help::help:

Merlin66
22-09-2011, 02:39 AM
I've trialed most of the "bits" you've got...
IMHO the one to hold onto is the SM40 and BF10.
The SM40 can be mounted on a suitable refractor (up to 1000mm focal length) and will out perform any of the Lumicon bits you have.
There's no benefit it trying to add the Lumicon Ha filters to the SM40 - doesn't work - sorry.
Sell the bit's and try to find either another SM40 for double stacking or move up to a SM60.....keep the BF10 - they are VERY difficult to replace.
HTH

MLyons
22-09-2011, 05:05 AM
Thanks ever so much Merlin and Al, that's exactly the kind of advice I wanted to hear.:rofl:

Seriously though, that is what I had anticipated, but I needed confirmation from you good folk here on the fora.

Do I understand correctly that I could literally screw another SM40 onto the front of mine and that's what's known as "double-stacked"?

Many thanks.

Ps....anyone want to buy a Thousand Oaks or Lumicon Ha solar setup...going cheap....;)

Martin

Merlin66
22-09-2011, 05:35 AM
Basically yes.
The double stack arrangement needs the Tmax adjusting ring between the filters and also between the pair and the OTA.
This allows you to adjust one filter relative to the other to get best performance.
I use a SM60 double stack on an ED80- very nice!