steppenwolf

Well it looks in great condition and that explains the modification to the skirt on the dome section - I guess this is an additional drip rail?

Great news - you are in for a treat! A couple of pointers:- 1. Concentrate on getting the base of the dome and the top of the walls flat where each section butts up to the next as this will ensure smooth rotation. 2. Don't rely purely on the pre-drilled holes - file any out that impede 1. above - To be fair, my bolt holes were very well aligned straight from the factory 3. Spend plenty of time ensuring that the north-south diameter matches perfectly the east-west diameter on the walls before you bolt it down to the plinth.

Ooooohh, how very exciting!!

Thanks for your comments, Adam. Thanks, Mick.

Thank you Rudd, I'm pleased you like it 👍 Thank you Richard, colour is such a variable thing. I like subdued colours as they make deep sky images look more 'dusty' which I guess is why I settled for my first rendition but the more saturated version also brings out some added depth! It is not unusual for me to do several orisons and in fact, my original is in fact two versions combined ....... Thanks, Martyn much appreciated.

I have my dehumidifier running all the time that I am not actually imaging and it has kept my gear in perfect condition for years.

Annie, hopefully that's all it is!

I would suspect that this is a dust mote in the light path - did you take matching Flat calibration frames during the same session and apply them before the rest of the processing?

I tend to think of my observatory dome roof as being a 'sacrificial dew-catcher' so I don't ever use a dew heater from within the dome. I have yet to find dew on my primary lens in any conditions - however, outside the observatory is a very different situation!!

A great project! Having completed my own remotely operated observatory I know how much work is involved and I wish you great success for the future.

Thanks for your comments, Steve - to be able to image under full Moon conditions certainly helped me to get the subframe count up!

Having gone through two Tak FSQ 85's which didn't perform as promised and then found from other people's experiences that QC on several other smaller widefield instruments was just too variable, I decided not to pursue that line until the industry got itself sorted out! So, I jumped the other way and bought the Esprit 150. I do have a semi-widefield instrument in my William Optics FLT-98 (fabulous optics) combined with a William Optics FR IV to give a focal length of just 509mm and reasonably impressive flat field if I follow a very rigid assembly procedure to negate the risk of tilt and get the spacing between the focal reducer and camera tuned correctly (I have a vernier scale on the FR IV for this very purpose!). The Esprit 150 is a keeper as is the FLT-98 ........

This is an interesting comment as Starlight Xpress indicate that you can bin the images 'in camera' using my Starlight Xpress SXV-M25C colour CCD camera. Here is an extract from the manual:- Using the ‘Binned’ modes: Up to this point, I have assumed that the full resolution, imaging mode is being used. This is essential for colour imaging, but it will often provide more resolution than the optical system, or the seeing, allows. ‘Binned 2x2’ mode sums groups of 4 pixels into one output pixel, thus creating a 696 x 520 pixel image with 4 times the effective sensitivity. Using 2x2 binning, you can considerably improve the sensitivity of the SXV-M25C without losing a great deal of resolving power, so you may like to use this mode to capture many faint deep-sky objects in monochrome. Other binning modes (3x3 and 4x4) are available and will further increase the image brightness and reduce its resolution. However, generally, these are more useful for finding faint objects, than for imaging, as the colour information is lost in all these modes. However, it is entirely possible that SX have not described the process in sufficient detail? My own interpretation is that colour or not, the sensor itself is still just a mono sensor (and, therefore, can be binned) with a set of filters (The Bayer Matrix) sublimated on top of it which can later be used to produce a colour image during the de-Bayering process.

Thanks, Dave. Yes, I really wanted to separate those two stars but the 3nm Ha filter and deconvolution in PixInsight made that possible. Yes, I do love my Esprit 150 and to think that I nearly let it go early on as I really wanted a widefield instrument (but there wasn't anything that suited my requirement) and thought I had made a mistake! I certainly didn't make a mistake and wouldn't part with it now.

Thanks for your comments. I usually just stick with one object unless it is only visible for a short period during darkness in which case I have a secondary target set up ready to go when the first passes my chosen 'horizon'. I always aim to get the most out of any clear night as they seem pretty scarce these days!

OK guys, here is the full resolution image for what it is worth (cropped a little to allow for an orientation mismatch caused by having to remove the camera to review some equipment ........):-

That's correct, the Bayer Matrix will be destroyed so you will only get a mono image and lose some of the sensitivity gain because of the filter matrix but it can physically be done.

Binning (for example 2 x 2 binning) is a mode on a digital camera that treats groups of four adjacent pixels as a single 'super-pixel'. This super-pixel has greater sensitivity that a standard pixel but NOT 4 time greater sensitivity! This mode can be useful for imaging dim objects in shorter exposure lengths and for improving the signal to noise ratio in an image but, of course, there is a trade-off although the same full field of view will be in force, the resolution will reduce proportionally. Have a quick read of this article.

OK Alan this is what you should be entering in C du C under Display - Finder Rectangle (CCD):- Width 100.8 Height 67.0 Later, when you have your template centred on the object that you want to image, toggle the rotation mode on by typing 'Shift C' which will make the template go white. You can then rotate the template around the object using the 'arrow' keys on your keyboard until you get the orientation that you want. Finally read off the rotation angle shown on the template and apply this to the orientation of your camera on the telescope. Hope that makes sense! AstroFlat can be purchased from here. I never leave home without it but then I am a beta tester for it!!

Alan, if you can confirm your telescope focal length for me, I will tell you which figures to place in C du C and how to rotate the template on the fly to get this spot on. Please allow for the focal reducer if you have one! Here is a quick look at your data to give a more coherent background to the image. This was done in PhotoShop using the AstroFlat plug-in, levels and curcves:-

Here you go Rodd, just for you! 😁 I tend to slightly under-saturate this type of object to make it look more 'dusty'' but I like stronger colours too:- So true!!

Very nice indeed and just goes to prove that you don’t need tens of hours of data to get a great result - nice smooth processing as well,

Thanks, Grant, there was a spell of clear skies around the most recent full Moon (now there's a surprise!) so I captured all the Ha then, collected the OIII over 6 nights in August and the SII in one night (26th August) - in the UK, you have to take your chances when they appear! Thanks, Martin, yes, the OIII and SII seem very poor and despite the number of OIII subframes I was disappointed by the noise levels. This took a lot of processing and several notable failures!! Get back on it, it is a lovely object from close in and in a widefield view as MartinFransson has recently demonstrated. Thanks, Alan - I do have the advantage of an observatory so I don't have to worry about sleep deprivation! The Esprit 150 is an amazing telescope, what a shame you missed this opportunity. Thank you - hmmm 3 nights with your dual rig, I HATE YOU!! 🤣

I really should have updated this earlier but I am pleased to report that the problem with the new PC turned out to be a faulty RAM module which has been replaced and I now have a fully functional system that is as stable as a stable thing on solid ground!! 👍

IC 1396 (centred on The Elephant's Trunk Nebula region) Introduction The nebula is part of a rich area of emission nebulosity catalogued as IC 1396 in the constellation of Cepheus and lies about 2,450 light years away. In this image, only the ‘trunk’ region is shown but the object gets its name from the extended region to the north that forms the Elephant’s head, ears and the base of the trunk that then curves down and then up again in the typical poise of an elephant placing food in its mouth with its trunk! However, this fascinating and to me, slightly eerie feature reminds me less of an elephant's trunk and more of an alien apparition walking out of the mist! The bright edge to the trunk itself is the compressed ridge of a dense ionized cloud that is being illuminated by the magnitude +5.7 star (HD 206267A) to its east whose powerful stellar wind is driving the formation of new stars. This massive star is part of the Trumpler 37 (Tr 37) star cluster. These same stellar winds are sculpting the wonderful shapes and filaments that are visible throughout the globular head of the nebula. The darker clouds are silhouetted against the backdrop of glowing hydrogen gas from the surrounding nebula, IC 1396. Not visible in this image but worthy of note as it is just on the edge of IC 1396, is a bright red star named The Garnet Star by Sir William Herschel although it was originally discovered by Johann Bayer. Mag. +4.23 Mu Cephei to give it it’s Bayer identification, is a red supergiant believed to be the largest star visible to the naked eye, with a diameter of 3.86 billion miles across. That’s much further than here to the pub ...... The Elephant’s Trunk Nebula is wonderfully rich in Ha emissions and previously I have been content to produce a mono image using this filter but this time round I was determined to capture some OIII and SII data to produce a colour rendition. The OIII and SII proved to be very thin and the poor weather conditions resulted in a meagre amount of SII but I went for it anyway! I use Astrodon 3nm Ha and OIII filters but simply cannot afford the additional cost of an SII filter at this bandwidth so I used my 7nm Baader SII filter to complete this image. This bandwidth disparity introduces problems of its own with regard to star sizes so I had some fun and games removing halos caused by the SII data but finally came up with an image that I liked and present here. I also show the OIII and SII data for comparison so that you can see what I had to contend with when it came to processing. The Ha data was collected while the Moon was too prominent for any other filter and the other channels were captured whenever there was a break in the September clouds. Image Stats Mount: Mesu 200 Telescope: Sky-Watcher Esprit 150 Flattener: Sky-Watcher Esprit specific Camera: QSI 683 WSG-8 Filter: Astrodon 3nm Ha, 3nm OIII and Baader 7nm Subframes: 42 x 1800 sec Ha, 39 x 1800 sec OIII, 10x 1800 sec SII Integration: 45.5 hours Control: CCD Commander Capture: MaxIm DL Calibration, Stacking and Deconvolution: PixInsight Post-Processing: PhotoShop PS3 Location Constellation Cepheus RA 21° 35' 0.76" DEC +57° 29' 48.50" Distance 2450ly