Omeag Bob's Ca H filters.

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Omeag Bob's Ca H filters.

Post by Valery »

Hi all,

I just visited Bob's eBay page with ads of this filter Ca H.

The ads says it is 2A filter. But the graph shows that this is almost 5A FWHM filter!

Why Bob is trying to make his filters sound better than they are??? His prices are good,
but the filters must be advertised as they are, not with false band pass WFHM value.


Valery.


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Re: Omeag Bob's Ca H filters.

Post by marktownley »

Just one of the many reasons I take them with caution...


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Re: Omeag Bob's Ca H filters.

Post by Montana »

That's a bummer! I'm not expecting much out of this filter when it comes then. Oh well, you can all say I told you so. I'll give a frank opinion of it and you can all save your money :roll:

Alexandra


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Re: Omeag Bob's Ca H filters.

Post by Brett »

Valery, have had a look again and it seems to be about 5A indeed...


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Re: Omeag Bob's Ca H filters.

Post by marktownley »

Montana wrote:That's a bummer! I'm not expecting much out of this filter when it comes then. Oh well, you can all say I told you so. I'll give a frank opinion of it and you can all save your money :roll:

Alexandra
No, we wouldn't do that, it would be mean, and we're not like that. However we are all genuinely interested how you get on with it and what you find.


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Re: Omeag Bob's Ca H filters.

Post by Brett »

Yup, like Mark said. Very interested to see some results!


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Re: Omeag Bob's Ca H filters.

Post by swisswalter »

Montana wrote:That's a bummer! I'm not expecting much out of this filter when it comes then. Oh well, you can all say I told you so. I'll give a frank opinion of it and you can all save your money :roll:

Alexandra

Hi Alexandra

you sure have seen my comparison CaK / Ca H II (Daystar) so that is what you should get with Bob's filter


http://solarchat.natca.net/viewtopic.php?f=4&t=14370


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

"you sure have seen my comparison CaK / Ca H II (Daystar) so that is what you should get with Bob's filter"

caK was made by who?

CaH looks more washed out compared to caK which caH filter from daystar is that?


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

also I did a search on "ca H solar photos"
a few came up and had stated 5A bandwidth
I did notice ca H in general not as dramatic as caK

is daystar 4-5A also? is this wider bandwidth because it was designed for visual use?


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

scan thru this web site see ca H 5A pictures scattered thru out
http://www.hydrogenalpha.com/


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

Valery ,Mark I agree that you should state true bandpass

but IMHO and this is just a WAG(wild ass guess) . bob basically copied what others have done
and replicated it for 299

found another
http://www.icstars.com/HTML/SolarSectio ... Oct21.html


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Re: Omeag Bob's Ca H filters.

Post by swisswalter »

highfnum wrote:"you sure have seen my comparison CaK / Ca H II (Daystar) so that is what you should get with Bob's filter"

caK was made by who?

CaH looks more washed out compared to caK which caH filter from daystar is that?
Hi John

These are my own pics. All made withhin an hour

CaII H, 3969 A, Hw 5A, operating temp 73 F


Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE :)

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Re: Omeag Bob's Ca H filters.

Post by highfnum »

Walter
so your cah is a daystar??


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Re: Omeag Bob's Ca H filters.

Post by swisswalter »

highfnum wrote:Walter
so your cah is a daystar??
Hi John


yes, see my reply above


Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE :)

from 7 am - 7 pm http://www.nanosys.ch

from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa ;)
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Re: Omeag Bob's Ca H filters.

Post by Montana »

Well, my Calcium H came yesterday. The hubby was in a stinking mood as he was stung for an extra 20% by the postman. I forgot that! I wish Bob wouln't put $299 on the envelope :(

On close inspection the filter looks very nice and comes in a threaded holder. However, the data sheet shows 5A and not 2A as stated. I will test it though in the next few weeks (usually by the second week in Feb) but it may be a return as I feel it will not do the job. I hope the taxman will give me back my 20% as well.

Alexandra


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

Looks like bob simply copied other vendor band pass
I'm getting 'booster' filter for Ca H from bob based on Valery suugestion

Ill let you know asap
not defending bob
but filter is same performance at approx 1/10 cost of more expensive vendor
Also i didsome research
Ca h id more muted because it from higher
level in atmosphere

I find it interesting it its own right


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Re: Omeag Bob's Ca H filters.

Post by Montana »

We'll see :) but I wouldn't call CaH muted http://solarchat.natca.net/viewtopic.php?f=8&t=14283

However, yes http://www.company7.com/daystar/products.html here they say the CaH band is around 10-12A wide and the picture from their 5A CaH filter looks the same as the one you took with Bob's. However you need around 2A to see the interesting centre line like in Wah's image. Like for CaK, a Baader K line filter is quite uninteresting compared to a CaK PST ;)

Alexandra


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

Additional caH filter element is in
ill let you know soon


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

Did quick preliminary
view was a bit improved
but still not like cak
will try sunday with skybender


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

"We'll see :) but I wouldn't call CaH muted viewtopic.php?f=8&t=14283"
Montana do you know bandpass for this image ?
I searched on internet - I could not find an filter caH images that compare to SHG caH images
It seems filter type caH are 5A or more


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Re: Omeag Bob's Ca H filters.

Post by highfnum »

Wah just gave answer of 0.2A
that is very beyond any filter
I've seen


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