Baader versus Astrodon Gen 11 filters

[gregbradley]

I currently am using Baader 50mm square filters for LRGB.

I sometimes have trouble getting a decent RGB combine.

I have used Astrodon Gen 1 filters before with an STL11. They were
great in that they were very easy to get an accurate RGB combine.
They did however have bad reflections in the green filter.

My Baaders aren't too bad for reflections but they still get some on bright stars in some setups.

Is there anyone in this group using the Astrodon Gen 11 fitlers who'd like to give a review?

I like the idea of the filters more accurately matched to the type of camera chip.

Greg.

[Doomsayer]

I have a newish set of 50mm LRGB Gen II e-series Astrodons for my STL6303-RC rig to replace a Gen I set. I haven't really fully tested them yet due to the paucity of clear sky time in recent months, but I do feel they are a little less prone to reflection issues than the Gen 1's. I have field flattener lenses in the way as well, so off axis bright stars are still to be avoided regardless of filter. From memory the filter cutoffs are a bit different to the Baaders. I'd have to check CCDautopilot for my recent G2V measurements. I also have a set of 50mm square Baaders for an FLI filter wheel - haven't gotten around to trying these out.
guy

[gregbradley]

You're in a unique position to see the differences.

So reflections are only a bit better than the Gen1?
Flatteners were the issue with the 16803 chips and reflections.

There was a long thread about 1.5 years ago when the 16803 cameras came out from Apogee and FLI about reflections. Baaders came out looking good from that. But then Astrodon brought out his Gen 11 with the anti reflection coatings.

Greg.

[Doomsayer]

I feel the various unavoidable effects with (very) bright star reflections/halos etc with the field flatteners in my RC are reduced significantly - less 'light splash' or something similar. I tend to avoid such targets anyway as blooming becomes a challenge as well with the NABG chip. Astrodon took the gen1 criticisms pretty seriously when reincarnating the gen2's. As to whether Baader is still better, I can't realy say. I'm happy with the gen2's for my particular setup and needs.

[gregbradley]

I talked to Jase about this and he uses Gen 11 Astrodons and likes them.
An FSQ has a lens right at the back of the scope much like a flattener so if he isn't getting reflections then that probably is a very good test.
That's all I needed to know. I'm going to get some. I think I was getting better and easier results with the Astrodon Gen 1 when I used an STL than with the Baaders (which are still very good).

Greg.

[marco]

Saw this topic only now (I lately connect to the internet very irregularly). I owned and used with my Proline 16803 AD gen I, AD gen II and Baader LRGB. All 50x50. I used them with TEC140 fitted with a field flattener.

To my experience:
- AD gen I are quite nice in terms of color separation/balance but with very strong reflections. Totally unacceptable. Sold.
- AD gen II have a similar color separation/balance (couldn't see a big difference) and a bit less reflections, however still very evident and not acceptable. sold.
- Baader have by far less reflections and a quite nice color separation/balance, even if *slightly* worse than AD. This however is quite subjective and the image processing has much more effect that the filters themself. These are the filters I use now.

Personally I cannot understand why AD cost much more than Baader, considering the performances I would aspect the opposite.

I also own and use the AD gen II Ha (5nm) and OIII (5nm), both very good filters. They are very close to be parafocal with the LRGB Baader filter set (all of them are said to be 3mm thick), even if not completely. Since I have now installed a robofocus unit and do focus automatically, this is no longer an issue (but maybe is for somebody else).

You can see several pictures taken with these filters in my CCD gallery (http://www.astrosurf.com/lorenzi/ccd.htm). All "square" pics were taken with the Proline and the filters above (check the notes).

Hope this help
Clear Skies
Marco

[gregbradley]

Thanks Marco.

I ordered a set already so I guess I'll find out.

With my Baaders, I am not sure if I am doing something wrong but often when I do the LRGB combine in CCDstack the colour can be wacky.
I have at times had to normalise RGB and then do a combine and it comes out OK. Perhaps I have stretched each RGB at different rates
and it affects the combine.

I never had that happen with the Astrodons.

Did your PL16803 have the mask fitted at that time (early models did not).

Also it is good practice to blacken the filter edges.

How do you combine your RGB?

Greg.

[marco]

Combination ratio I used so far is 1:1:1, but I promised myself to do a G2V calibration asap.

Not sure to understand what do you mean about the mask, what are u referring to?

Marco

[gregbradley]

Hi Marco,

The mask is a black metal mask with a cutout the size of the sensor to prevent stry light reflecting off bright parts.

I believe they are standard on Prolines made after a certain date.

Greg.

[marco]

Thanks Greg, understand. Not sure my camera has it, to check it I should remove the CCD head and look trough the optical window but since I only remotely control my telescope that is impossible.. maybe something to check next time I come down under..

Marco

[gregbradley]

If you have the serial number of the camera you could ask Greg at FLI and he should be able to tell you. He may be able to do it even without the serial number.

Greg.

[gregbradley]

I see you have a Pentax 300mm EDIF lens. Is that the 6x7 medium format lens?

If so where did you get it from? They seem to be quite rare.

Greg.

[strongmanmike]

Well given I use Astronomik filters, I'll put in a plug for them.

I have the new low reflection TypeIIc series 50mm square filters in my CFW-5-7 on my PL16803 and so far I have seen no significant halos, in any of the images I have taken, nor out of field star flares with my AP152EDF which has a 4" field flattener to boot (my chip has the mask though) No halo removal has been done on any of these shots either:

http://www.pbase.com/strongmanmike2002/recent_images

There are some bright stars in some of these shots but a better test will come with the Orion Rgion and other "really" bright stars of course but then most filters have issues in these areas anyway from what I can see..?

Mind you the FLI CCD window is ultra low reflection too though ie > 99.7% transmission across visible wavelengths and virtually 100% transmission in the green. So don't under estimate this aspect of reducing halos.

http://www.pbase.com/strongmanmike2002/image/125899124/original

As far as colour balance goes..?...I haven't seen anything that would worry me :shrug:

Just my 2c worth :)

Mike

[gregbradley]

Yes I have noticed that Mike. You seem to have practically no haloing even on bright stars. I get some with the Baaders. I wouldn't call it bad but I wouldn't call it great either.

It depends a bit on your setup too. RCOS scopes don't seem too affected but APOs with a flattener so close to the camera seem worst affected. So you example is a good one.

I have a set of 50mm square Astronomiks but the earlier version. I quite liked them. My only complaint was when I got them Gert (is that his name?) didn't sell the packers as his filters are thin. That meant I had to jerry rig mine with bits of tape and cardboard washers and a couple got damaged because they weren't secured.

Then when he brought out the spacers he wanted $100 for them which was a bit rich seeing as the filters were useless without them. But then dealing with European companies is very different than dealing with US companies. They are not service oriented or consumer oriented like the Americans and so are not great to deal with. I would always buy from a US company over a European company if I had a choice. They just don't seem to get it (perhaps 1000 years of history is a bad thing and their feudal haves/have nots type of society is ingrained too deep). Its one of the things I love about Australia it is a very fair and even society and companies here are very service and customer oriented having taken on the American model.

Sorry for the rant,:sadeyes: having said that the Astronomiks look good! What about the colour balance though? I have recieved my Astrodons now so I guess I will know soon if I made a mistake or not!:lol:

Greg.

[strongmanmike]

Like anything, there are good and bad stories Greg, anywhere you look, regarding customer service. I have had no issues with Gerd.

I edited the last post to cover your question re colour balance.

I use my eye for this process anyway and not G2V so perhaps I am not being quantitatuive enough here..?

Mike

[gregbradley]

True. Gerd was good but really he shouldn't have been selling these thin filters without the spacers. Its a bit like selling a car and saying- oh you wanted a steering wheel with that? His fliters are good and I think he is also the cheapest. I got good colour from them without any difficulty and also got pleasing star colours. I for some unknown reason to me, sometimes get weird colour combines with the Baaders and then have to normalise the RGB to get a proper colour combine. Not sure if that alters things when you do that but it doesn't work if you don't. Perhaps something in my workflow is off. I never did that with Astrodons hence trying them out again. He got a bit of internet beating over this filters when the 16803's came out with really bad reflections from APOs with flatteners (all of them of course with a 16803 chip). All scopes need a flattener with these large chips.

I haven't done G2V yet but I will as I want to upgrade all aspects of my imaging and colourbalance is often a tricky point of imaging.

There is a program you can get that helps with this. I have seen it talked about on the SBIG yahoo site.

FLI research filters also seem to be good as are SBIG filters. I presume FLI research are really Custom Scientific rebadged - but don't know for sure.

Greg.

[marco]

Hi Greg, yes, it is the 300 EDIF for the 6x7 format. And yes, I kept looking on ebay for about one year before finding one to buy, they are quite rare. I confirm they are an excellent match for the 16803 chip, providing corrected images all over the field with very little chromatic aberration (better than many apo lenses out there..).

Clear Skies
Marco

[gregbradley]

Thanks Marco.

Greg.