ACROMAT for Colour Photography????

[FOOTPRINT]

Hi All,
A friend of mine sent a "Baader Fringe-Killer" Filter to try out, so in addition to using it on the ED-80, I gave it a try on the "Skywatcher 102" Acromat to see what would happen, amazing results, only the smallest amount of Blue Fringe around bringht stars, might be the breakthrough needed to make the Acromats a useful imaging tool, ill post more later.

1 x 6 Min. Exp. at ISO-800, DF removed, MODIFIED CANON*, guided.

* Tested using the original Canon UV/IR Filter in the light path + the Fringe Killer Filter, everything out of Focus, Me or It I dont know as yet, re-running this test.

regards...........Jim

[[1ponders]]

Looks promising Jim :thumbsup:

[RB]

Amazing result Jim,
Thanks for sharing the image and info.

[atalas]

Good result Jim , the UV block is definitely doing a good job .

[Robert_T]

that's great, if you hadn't said otherwise I would have assumed it was taken with an ED or other apo:)

[tornado33]

Yes its got rid of colour fringing, might be surprising how many refractors and lenses can now be used for good astro imaging with this filter.
Scott

[FOOTPRINT]

Hi All,
Did a follow up last night, took M42 with the Skywatcher-102 (F-5) and although greatly reduced, there is some BLUE fringing visible in the RAW image, seems processing further reduces this effect, looks like this Filter makes an Acromat useful for Colour Imaging if you are happy with the results.
Pix.= 4 x 5 Min. Exp. added DF removed, ISO800, No colour adjustment made at any stage of processing.

cheers....Jim

[mickoking]

Terrific looking Images Jim. I am a big fan of Synta refractors and it is great to see them producing good images.

[Itchy]

Hi Jim

I loaded your jpeg into ImagesPlus and applied a star size and halo reduction. This tool gives you the option of applying different strengths to each channel. So this one is done with a stronger reduction in the blue channel. it seems to remove any residual blue halos. What do you think?

Cheers

[ving]

I think they all look great :)
thanks for posting them :D

[janoskiss]

That looks very pleasing to the eye Itchy! Your processing has given a much warmer film-like tone to the image IMO.

Jim, I guess you could also take three separate shots for red, green and blue. In principle, you would not even need filters with a colour digital camera, just the ability to adjust focus for each colour separately. Maybe a pair of red-blue 3D glasses is all you'd need. :)

[RB]

That's a great improvement Tony, Star size and halo reduction is new in IP 2.75 isn't it?
I can't find it in IP 2.5.

[Itchy]

Yes it is part of the 2.75 beta. You can achieve a similar result by using a duplicated image and applying an edge extraction to the blue channel only and then subtracting that from the original. It is nice to have it automatied though.

If you do have 2.5, you can get the betas just my asking mike to put you on the list, although I think it is in final beta now

Cheer

[FOOTPRINT]

Hi Tony,
I forgot to reply to your post re Pix. Mods. yes very good, im waiting for the final Beta or version, to see what he comes up with in IP, The Acromat is not as sharp as an ED scope as regards focussing either, well it cant be even with the Fringe Killer filter, as the colours dont all arrive in phase, bit like a prisim, but if you cant afford an ED or apochromat you can get acceptable results, what id like to see is an ED 102mm at F5 or less (if ED glass will still work at this range) would give a great FOV and more light gathering.

cheers....Jim