More Spiders about! My NGC2070

[Itchy]

Hi Everyone,

First time serious imaging in a month. I finally got to try out the MPCC and the Baader UHCs filter. I must say I am impressed with both. Time spent on drift alignment was well worth it.

This image was actually a bit of a muck up. It was midnight before I realised that my 300D was set on ISO200 instead of the usual 1600. I was blaming the unusally dark images on the filter. I processed them anyway and suprisingly I still had to use Scott's method of compositing with masked layers using a darker version of the same image. Thanks Scott.

I would like to try the same object at 1600 to see if I can get more detail. maybe next time

http://users.bigpond.net.au/itchysas...3iso200Web.jpg

Meade LXD55 SN10, Canon 300D (stock), Baader MPCC, Baader UHCs Filter, 20x180sec at ISO200, manually guided.

Converted, CFA calibrated (Autodark, Flat, Bias), aligned, combined (sig avg), DDP, Star Size&Halo Reduction in ImagesPlus 2.75 beta 4. Levels, Curves, Composite, Luminace sharpening in Photoshop CS. Per channel Noise reduction in Noiseware.

Comments and criticisms more that welcome.

Cheers

[davidpretorius]

Lovely Tony,

Monday night showed this up a treat. One day i will takes some lovely pics and autostitch together to make a wide field of this fantastic area.

[seeker372011 (Narayan)]

very nice work..to my eye it has a sort of H alpha feel to it...

[h0ughy (David)]

Nice stuff there tony! I hope you can get the next shot

[PhotonCollector (Paul)]

Well done tony, looks like that coma corrector really did wonders.

[atalas]

Don't know what your talking about Tony but It's a sweet shot dude !

[33South (Chris)]

Originally Posted by atalas

Don't know what your talking about Tony but It's a sweet shot dude !

Likewise !!!

[rumples riot]

Lovely image, the tarantula is always a great sight to behold. Well done.

[Itchy]

Hi Everyone


Thanks for the positive comments. It's great to get feedback from my learned colleagues.



Paul,

I think I love the MPCC. I'm having discussions at the moment with a bloke from the LXD55 group. He has apparently done some ray tracing with the MPCC and the Meade SN scopes. Apparently there is some slight over correction resulting in minor spherical aberations in the centre and also some minor chromatic abberation. He says that the corrector to camera distance can be changed to minimise "residual coma", but he hasn't given me the corrected distance yet. I'll let you know when I know.

All I really know at this point is that my images are much better with the MPCC than without it, so far!

Cheers

[Striker (Tony)]

Just beautiful Tony,

That looks like a lot of proccessing....great job

[avandonk]

I was under the impression that SN telescopes were designed to minimise the coma inherent in Newtonian telescopes.So a coma corrector designed for a standard Newtonian would tend to overcorrect if used with a SN.I assume SN means Schimdt Newtonian.In fact any given coma corrector only works well for a limited range of F values, and are more useful at lower F values.Ie F6 or less.

Bert

[Itchy]

Originally Posted by avandonk

I was under the impression that SN telescopes were designed to minimise the coma inherent in Newtonian telescopes.So a coma corrector designed for a standard Newtonian would tend to overcorrect if used with a SN.I assume SN means Schimdt Newtonian.In fact any given coma corrector only works well for a limited range of F values, and are more useful at lower F values.Ie F6 or less.

Bert

Hi Bert,

You are correct. The SN is designed to minimise the coma inherent in low ratio Newts. However, the corrector plate only does part of the job. My scope is an f4, but the SN design corrects the coma to that of about an f6 newt. Visually, my SN produces bright flat images to the edge of the field. However, in digital images, there is considerable distortion, particularly in the corners of the frame. The MPCC is designed to correct the coma in Newt's from f4 to f6, so I thought it would be worth a try. Apparently there is some overcorrection that effects the centre of the frame, but it is so slight as to be unnoticeable. I certainly can't detect it.

There is definitely an improvement over not using it. Check out my Eta Carina taken without the MPCC cf the Tarantula with it.

Cheers