tooth_dr

Could you post your Esprit 120 image, just to gauge? The 150 is outside my price bracket. The 100 doesn’t quote a corrected 44mm imaging circle, only up to 40mm. But I already have a ~500mm scope so was looking the longer FL.

Thanks Ken. Someone on here recently posted an image from a 6200 and an esprit. It might have been @gorann

I did read that, it’s seems uncertain what difference a sensor grade makes in CMOS as the tech is new. I am using two old grade 2 CCDs and the defects are noticeable but calibrate effectively. If the CMOS behaved the same then that would not be a problem.

The Esprit 120 and 150 claim to offer a 44mm flat imaging circle

I have been browsing the QHY website and their 294M model has a feature called called extended pixel mode: ”The original 294M chip, the SONY IMX492, is an 11.7-megapixel chip.When the extended pixel mode is enabled, the original single pixel can be split into four pixels to about 46.8 million pixels.The process is similar to a reverse bin” Have you enabled this?

This is good value? https://www.modernastronomy.com/shop/cameras/cooled-ccd/qhy-cooled-ccd-cameras/qhy600l-lite-mono-cmos-cooled-camera/ I was thinking about the price point of the 268M? If it’s much more than the 268C version then the 600L represents exceptional value. It’s still dear but a heck sensor area in mono in the latest CMOS technology?

Thank you Tom. Exactly my first thought too, was only when I looked at another image the next day I realised it was part of the nebula.

Yes sorry 31.5mm. Did you find any of the above information useful?

Very nice Ciaran, that is a good combo Have you considered a second ED80?

Very interesting as always Vlad. The crop looks to be just outside the FOV of the 178. A centre crop may provide a better comparison

~Wow that wider image is spectacular. Thanks for sharing! I 100% will be dedicating time to this region. I feel like I've been faffing around a bit recently, nice to settle down into a project. I wonder how the Nikon with the 180mm lens would fair out - would I be right in thinking a single frame would cover it - it calculates at 11.5 degrees by 7.5 degrees of area.

I found this on my HDD, a single sub, with a similar lens, 105mm F2.8, in a densely populated star region. This was shot wide open at F2.8, 120s, ISO800. Now the pixels at x2 the size of yours at 5.7um, but it's shows what a macro lens should be doing. There is some flaring visible too, worse on brighter stars. Perhaps your spacing is wrong, or there is tilt, or your lens is defective, but it should be better you would think.

For it being stopped down to F3.3, and using an Ha filter, and for the size of the sensor, I would say that it is just ok.

I’ve literally just dusted off my Sigma Macro 105mm F2.8! I used it quite some time ago with a canon 40d and it was nice over the whole field wide open. Planning now to use on a CCD. From my reading on macro lenses, they seem to generally have a very good flat field. The sigma I have also has very low CA, and the review I read scored the canon also low for CA. The sensor is small on the 178 compared to a DSLR so you really would expect sharp stars across the entire FOV. I printed a canon to T mount adapter the other day for my 120MM. It has 12.5mm backspacing, just like your 178MM. So you should have 44-12.5= 21.5mm between the lens flange and the 178.

Yes you are right. There are some OAG that are thin, including the QHY version at 10mm, you’ll just have to be careful with adapters which may add 2-6mm depending. You mustn’t be far too away with the KAF8309 though or else it wouldn’t have focused on infinity.

I’ve not spoken to all the ZWO suppliers but the one I did had no information on release. Info above is 2 weeks old too

Once I heard there was no idea on the timing of the ZWO camera, I kinda ruled a line under it for the time being. But I’ll keep my interest in it for sure. I suppose MA is anticipating X cameras coming in so they take a list of X people in the order of their registered interest. I can’t see there being issues selling them if any one pulls out

Well I decided to put my name down for a QHY268M. There is a small batch coming in (hopefully) in Jan. Always a risk being an early adopter, but all things considered it’s the ideal camera for my setup. There seems to be no information around a ZWO2600M version so despite its more favourable back spacing, I can make the other one work just fine. Anyone else on here expressed interest in it ?

As you say in your first post there is a lot of information about individual filters out there. I've answered your original questions, and let you do your own research now about individual filters.

You still wouldnt buy the non-CCD version. You quoted Astronomik UHC - this is what they say about the product

You need to maintain the correct backspacing of the lens, as if it was intended to have been used on a camera body. The Canon is backspacing 44mm, .... QHY268C has a back focus of 23.5mm, so in other words you have 20.5mm to play with between the flange of the 268 and the rear of the lens. Assuming the Canon adapter is about 10-12mm, you wont have much space for anything else. If you go outside the 44mm you will not be able to focus at infinity.

This one block UV-IR so no extra filter needed. The CLS version doesnt so you would need the separate UV-IR cut filter - so you wouldnt buy this version.

Only lets Ha through, therefore dont need IR cut Here is the graph, and based on that you would need an IR cut filter, however I have never used one so dont know how the two filters would react/reflect together. I think it's more of a visual rather than a photographic filter.

Thanks, means a lot Thanks Andrew. Diffraction spikes courtesy of the luminance from the Epsilon. Thank you! It’s a busy region, hard to get a balance.

Here is my latest image. It's an LHaRGB image taken with a dual rig of Tak Epsilon 180 and SW ED80. L = 175 minutes Ha = 250 minutes R = 70 minutes G = 65 minutes B = 70 minutes I need to work on how to control the stars during a stretch, rather than dealing with them afterwards, as the latter is easier but leaves artefacts. Reasonably happy with this one though, any comments welcome as always good, bad or indifferent. I have been changing the spacing on the Tak, and it's got better, but it still looks a little too much, so I'll remove a small 0.5mm spacer and see how that helps. Best wishes Adam.