cfpendock

I have seen many really good images of this in narrowband using various palettes, but always I prefer just the Ha. Excellent result! Especially considering the moon. I think you have justified the Astrodon filter.... Chris

Yes, nice field of view. Chris

That is good. I am very tempted to get a reducer for my C11 but the price seems very high. None on the second hand market that I've seen. But this M51 certainly shows it's potential. Chris

That TEC combined with the Atik 460 certainly does the job. Not to mention the expertise of the operators and the processing of course.... Chris

I certainly find that re-focusing interferes with guiding, so usually turn off guiding during re-focussing. Otherwise I need at least 2 minutes for the guiding to settle back down. But I've never had a problem losing the guide star. I don't use SGP, I use MaxPilote, but I think it does much the same thing. Chris

The reason I said adequate is that I think the field will not be completely flat - for that you need an Edge which is very expensive. However, depending on the field of view of the camera, this may not be a problem - in any case it would only affect stars and other objects closer to the edge of the image, e.g. if you imaged several galaxies within one field of view. For planets you will not be so interested in the stars and so I think that this should be less important. You need to compare the image size with the image circle of the scope for whatever camera you will be using. Just my opinion...... Chris

Should do the job adequately for planets and smaller galaxies, depending on the camera - I presume you will be using a video camera for the planets and something else for the galaxies which can be rather faint and hence require relatively long exposure times. The price seems to be very good indeed. Chris

That's what I thought - But then I found the new price is around £650 - seems pretty expensive to me - unfortunately mine is the Edge....I've not seen a second-hand one (for the 11"Edge). Thanks anyway. Chris

Thanks Bob. So, in my eyes, that makes your image even more remarkable - I was never happy with my CPC polar alignment with a wedge so I de-forked it and now use an equatorial, but clearly you have the wedge system sorted. I also always use 2x2 binning with my CPC for Lum as well as RGB, although some people reckon you can get better results without binning. But, even worse, I don't have the focal reducer so I image at 2800mm FL, which gives me around 0.5 arcsecs/pixel. Not so good for my UK skies.......hence the binning. I think that bloating is a characteristic of the CPC series, although I think that some bloating is inevitable at such long focal lengths. Chris

Very good. Was this using a wedge? Chris

Amazing image. And this is just Virgo.... Good for getting a sense of perspective on the near universe. I guess it would be exhaustive to list the ones with the "TEC implant"? e.g. M88? Chris

Not sure about that, but I won't argue. I often image smaller stuff at 2800mm, but even with binned subs there is no way that the seeing where I live is good enough to show really fine detail. I have also noted that some character from the south of France who regularly posts on this forum seems to get at least as much detail as me when using his TEC140, which is less than half the focal length. I suppose it's just possible he could have more expertise...... Chris

About as good as it gets. Is it cropped at all, or is this the normal image size for the TEC + Atik 460? Chris

For such a long focal length that is stunning. Chris

As I said, Bob, I like this. I think you have done very well to get nearly 12 hours total, considering the lousy weather. But I am surprised that you went for Ha rather than more time on the RGB - I presume you use a wedge with your CPC.... I gave up using a wedge with my CPC 11" because I was never happy with polar alignment and general stability, so eventually I "de-forked" it and now use it strapped to my EM200 mount (similar spec to EQ6). It seems to cope very well. Your image has inspired me to have a go at this one - thanks! Chris