RH200 looks at the Rosetta

[dvj]

Wrapping up my test exposures, here is a 24 x 600s image of the Rosetta in 6nm bandpass HA. STL 11000 camera and RH200 F/3.



j

http://img571.imageshack.us/img571/6541/rosettarh200.jpg

[peeb61]

Hi John..Jaw dropping!

Paul

[allan gould]

I'm amazed as to how quickly you have come to terms with this scope and the optics. Really excellent image.
Allan

[Larryp]

That's fantastic!

[gregbradley]

That's very good John. It seems indistinguishable from a high quality APO shot which is impressive for a compound scope. Do you have any comparison images from your FSQ setup to compare it with?

I am thinking it could be good for me travelling to my dark site where total length of exposure can be an issue with clouds, fiddling with gear etc. It would increase the number of keepers.

Is this with the STi plus lens guide kit? Spot on tracking.

Greg.

[Peter Ward]

Beautiful.

24x 10 minute subs...sigh....I wish for that much clear sky at present !

[dvj]

Hi Greg,

Here's the scope on my 1200 mount. STi and lens kit work just fine. The rings are mandatory IMO, replacing the single arm dovetail that comes as standard. OS provides these as an accessory, as well as the motor focus kit.

For RGB, 2 to 5 minute subs would be find at f/3, so I don't think assisted guiding would be needed if you have a precise enough mount.

It compares well to the FSQ at 9um pixel resolutions, but I am not sure the 42mm image circle compares well to the 80mm image circle that the FSQ provides. Plus at f/5, you can take full advantage of 3nm bandpass filters whereas you will get bandpass shift at f/3.

[dvj]

Thanks Peter, I'd like to see more work from your AP 305 Honders! Especially some deep exposure Ha images. I am pretty much shut down in Coonabarabran at the moment until the fire danger finally passes so I have time to play with RH in California.

[dvj]

Greg, here is an FSQ, RH 200 compairson shot. Which one is the RH? 100% resolution crop from the originals.

[gregbradley]

Oh good, a guessing competition!

Lock in the one on the right please Eddie!

Greg

[Peter Ward]

I'd go Right as well.

[Peter Ward]

:lol: That makes two of us!

Weather outside my place? Give you a hint...:rain::rain::rain::rain:

[alocky]

I'm assuming everybody is correct in guessing the right hand image - as there's a clear and significant reduction in the amount of noise, but there doesn't seem (on my screen at least) to be a similar improvement in resolution offered by the 8". Is the seeing the resolution-limiting factor?
cheers,
Andrew.

[dvj]

Resolution in this case totally dictated by the focal length and the 9um pixels.

[Ross G]

Amazing detail.

Beautiful tones.

A great B&W photo John.

Ross.

[Dimaz]

Great image John! What is the reason of spikes? There is not spiders in RH200.

[multiweb]

Terrific FOV and resolution. Beautiful scope. :thumbsup:

[dvj]

Spikes added. Special effects!:D

[Poita]

I still find it interesting the whole spikes thing. I spend so much time trying to get abberations *out* of my system, I can't imagine adding them in!

I know it is a personal preference thing, just like framing and colour pallete and everything else, just not my cup of tea. Do you have a version without them?

If I had your scope it would have lens flares in the images from the drops of drool falling from my chin onto the optical surfaces.

[Poita]

How much bandpass shift do you get at f3?

[dvj]

No bandpass shift because I used a 6nm filter for this shot. With the Astrodon 3nm filter, the transmission hit was at least 25% or 30% off maxim transmission spec. 3nm is no a recommend by me for F/3.

[dvj]

Yes I do have the original without the spikes. That's the cool thing about the Prodigital star spike generator. Add only where needed.

Here it is without star spikes.
http://img819.imageshack.us/img819/4606/rosetta28exp.jpg

j

[Meru]

That's a very beautiful image, you should be very happy John!

[Leonardo70]

What a rosetta !!! Congrats ...

All the best,
Leo