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View Full Version here: : Astrodon V Baader V Astronomik 50mm square filters


gregbradley
10-09-2010, 02:37 PM
I thought I would post my findings on the relative merits/disadvantages of these 50mm square filters.

I have 50mm sqaure Baader,50mm square Astrodon Gen11, Astronomik (not the latest Gen 11).

With the advent of the 16803 sized chips reflections became a real concern about 2 years ago and there was a lot of discussion on the net about it. So this aspect of the filters is very important.

The Astronomiks are quite good. I got good colour, they didn't cause any troubles and reflections were quite mild. They are thin at 1mm and they need a spacer otherwise they will fall out. Gert now sells the spacers for the 50mm square. He didn't when he first marketed them so they were not useable really then. I'd give them a 7 out of 10. Perhaps colour is a bit weak compared to the other 2 but pleasant. They are also a dye type filter where the glass is transparent with a coloured dye. The other 2 are mirrored reflection type.

The next set I had were the Baader's after reading a lot of posts. These give similar to slightly worse reflections (not bad but could be better). Colour is skewed to the red and red comes out stronger with these filters. They are not 1:1:1 colour combine as the marketing says the are. In fact they are a fair way away from that. What they don't take into account is the different CCD type responses to the various colours. Perhaps they may be 1:1:1 with an 3200ME chip - I don't know. But with 11002 or 16803 chips they are not. I also found them hard to get accurate colour combines perhaps because of this. I had to resort to normalising my RGB masters to get a sensible combine about 2 out of 3 images as otherwise I got silly results. I give them a 4 out of 10 for this otherwise they are good. They seem relatively parfocal - not as parfocal as the Astrodons though. There is a slight difference in focus between the filters so hence another slight weakness with the filters and not matching the marketing claims.

Astrodon Gen 11. These so far are by far the best. They are expensive but worth it. I get virtually no reflections, I get a very pleasing colour combine with no fiddling and a nice balance of colours without being skewed to one colour or another.

I definitely get the best results from these filters and I give them a 9.5 out of 10 with perhaps a mild deduction for being so expensive. But perhaps the rule of "you get what you pay for" applies here. I used to use Astrodon 50mm round filters with my STL11 and I liked those as well.
They did however give some reflections especially the green filter. So I would stick with the Gen 11 even if being used with a smaller chip.

A good choice of filters with these large chip cameras is vital and they are way more sensitive to reflections than the smaller chips. Part of the reason for that is they will always require a flattener in the scope and that these chips are quite a bit more sensitive than the 11002 chipped cameras (66% QE versus 40-50% QE).

I hope this may be of use to someone deciding on which filters to get.

Greg.

strongmanmike
10-09-2010, 05:23 PM
Astronomik filters are now all the latest generation low reflection (and they are even designing a third generation for some filters!) so this comparison is not valid any more unless someone is considering obtaining second hand older generation Astronomik filters.



Just make sure you are comparing the latest generations before making this decision :)...in light of this the price difference is indeed a factor ;)

Bassnut
10-09-2010, 06:10 PM
You on commission Mike? :P ;).

gregbradley
10-09-2010, 07:04 PM
Certainly your results speak for themselves Mike.

I liked the Astronomiks and I am sure the new anti reflection would be an improvement (although I did not have reflection issues particularly with the older set). They are good value but you have to add in the cost of the spacers when comparing them. In my case Gert wanted AUD$100 for them. I don't know what he is charging now. You can't use the filters without the spacers. I think the Apogee filter wheel is about the only one I am aware of that can take the thinner filters without the spacer with a special plastic washers and its recessed screw.

I still prefer the Astrodons as they are parfocal exactly on my CDK17, they are 1:1:1 ratio and they have even less reflections than the Baader and no colour bias towards the red. The matching of the filters to the type of sensor and its different colour sensitivities seems to be a real advantage.

ps. I blackened the edges of all my filters with a texta.

Greg.

strongmanmike
10-09-2010, 09:31 PM
Err? ..NO? what makes you think that? (http://www.pbase.com/strongmanmike2002/image/128058062/original) :lol:

No, no commission.

gregbradley
10-09-2010, 09:38 PM
Hey, how come you aren't out at the farm imaging?
Isn't clear there?

It is here even if a bit windy.

Greg.

Bassnut
10-09-2010, 09:44 PM
Yeah, well it says right there , 10% COMMISSION, well its a long weird foriegn word, but thats it IMO, your busted, punk. :lol:

strongmanmike
10-09-2010, 10:00 PM
A quick look at OPT shows more than a $100 difference in the filter price :eyepop:

Astrodon E series 50mm square unmounted Gen II LRGB set: $1200

Astronomik Type2 50mm square unmounted LRGB set: $699.95

Lot to consider there when all one needs to do is tweek your colour balance in Photoshop...? Or am I missing something?

Mike

strongmanmike
10-09-2010, 10:06 PM
4pm Car's all packed...wind, cloudy, starts to rain, wait, wait...6pm clearing a little...7pm seems to be clearing up, but still pretty windy..?...should I risk it, maybe its not windy out at Kurri, could drive out , setup in the dark on a wet field :scared:..??? Ah F'it, not worth the risk and even if it is clear out there the wind is blowing rather fresh, no observatory out there, no protection, is it worth it...:question:...crack a beer, eat some spag bole watch tele :mad2:...try tomorrow night

That's how it tis for me :sadeyes:

gregbradley
16-09-2010, 05:57 PM
LOL. Humorous.

Yes I get it, quite a problem.

I have had that at my dark site, to go or not to go. There though I have a weekender anyway so I have other things to do.

Its a bit like a surfer or a skier - are the conditions right or not?

Greg.

strongmanmike
16-09-2010, 10:58 PM
T'is alright, the next night was almost perfect and I grabbed the Milky Way centre and NGC 1316 region...so I do get lucky.... eventually :rolleyes: :thumbsup: