Laurin Dave

Don't crop, you lose the yellow stars which for me add interest and variety ... I'd run scnr over it though to remove the slight green cast

Cracking set of images Lee, particularly for such short integration times.. well done Dave

Nice.. great camera, I have the SX version. Gives great star colour and those lovely little diffraction spikes

The Soul Nebula (well half of it) in Cassiopeia in Hubble Palette and HaR_OiiG_OiiiB. SHO data captured in October and RGB last Friday, equipment used Esprit150/SX46 for Ha and RGB and Esprit100/ASI1600 for Oiii. Processed in Pixinsight and Photoshop, Ha and Oiii added to Red and Green/Blue using Blend mode lighten in Photoshop on a 50:50 mix of Starless/Starry data which I find gives nicer transitions around the stars. SHO image created using starless Ha, Sii and Oiii images with starry Ha used as Luminance, RGB stars then added to the SHO image by using blend mode lighten to add a channel split and black clipped (so only the stars are included) RGB image to each of the SHO channels. The original SHO image was then used as Luminance to merge the stars transitions. I'll get the other half next year.. Thanks for looking... Dave

Nice one Harry.... I was interested to see out how you find out, a quick Google revealed that Deep Sky Stacker can... it says 12271 stars.. although having just run it on my own Ha IC1396 gives a figure for the same area near to 20,000... whatever it is its a LOT Dave

Fabulous image Olly.. very deep, had me a bit confused though as it’s reversed left to to right Dave

Interesting comparison Steve.. are you using an OAG to guide? If so and that’s the side with better star size maybe there’s a bit of flex causing the difference.. also did you use flats to calibrate, if so it’d be worth looking at the uncalibrated subs to see if the gradient is the same.. Dave

I'd just experiment with how frequently you dither. My main scope has the CCD so its either 10 or 20 min subs... once I've got 5 or 6 dithers in an integration they combined with cosmetic correction sorts out any remaining hot pixels... So I'd start by just spreading 5 or 6 dithers over however long you're imaging for... So over say 3 hours do them every 15 subs or so... If you ar ein attendance when it dithers or focuses you can always restart the NB sub (or at least you can in SGPro)... Unfortunately my camera needs a window clean... although it doesn't look like the grease issues some have had..

Very nice Adam, certainly impressive for an hour, I was similarly impressed by the camera's performance when I took 30 mins of M31 through my GT71... As to the Darks and Bias question... I just measured my Bias it was 500.6 with a MAD of 0.6 my 300 sec Dark was 501.2 with a MAD of 1.0 with the difference being the 'snowstorm' of hot pixels... I'd say matched Darks as they'll best remove the Hot Pixels... dithering though is better still

(Also posted in Widefield, Special Events and Comets) Having stayed up till 3:30 last Thursday night only for it to cloud over just as Comet Leonard cleared the rooftops I fortuitously woke a bit early this morning to find it clear, so popped out with the binos and spotted it over the roof tops, quickly opened the observatory and captured 36 mins or so of 30 second R, G and B subs on the Esprit100/ASI1600 and 1 min Lum on the Esprit150/SX46. Data processed in Pixinsight using Comet alignment process to generate an aligned image of the comet, Starnet to extract the stars from the Star aligned image, Photoshop to remove the cometary blur from the starless star aligned image Pi to put the stars back, then Photoshop to combine the starry background with the comet . I used the RGB to produce a colour image and the Lum to produce a short animation. The red star top of frame is Tau01 Serpentis. Thanks for looking Dave

Having stayed up till 3:30 last Thursday night only for it to cloud over just as Comet Leonard cleared the rooftops I fortuitously woke a bit early this morning to find it clear, so popped out with the binos and spotted it over the roof tops, quickly opened the observatory and captured 36 mins or so of 30 second R, G and B subs on the Esprit100/ASI1600 and 1 min Lum on the Esprit150/SX46. Data processed in Pixinsight using Comet alignment process to generate an aligned image of the comet, Starnet to extract the stars from the Star aligned image, Photoshop to remove the cometary blur from the starless star aligned image Pi to put the stars back, then Photoshop to combine the starry background with the comet . I used the RGB to produce a colour image and the Lum to produce a short animation. The red star top of frame is Tau01 Serpentis. Thanks for looking Dave

Yes, just seen that from the photo.. I'd get onto APM for a new one

Hi Adam I'd fix the problem at source and get a new M63 to M48 adapter made up the correct length to screw direct between the FW and the flattener with a bit of slack for back focus adjustment via spacers.. Dave

That makes sense given that the extender is 43mm and with the correct T Ring a DSLR is 55mm

This is how to get the correct backfocus for the Esprit150ED.. the m48 thread on the zwo supplied 16.5mm adapter screws onto the extender tube screwed to the back of the flattener.. you may need to put a spacer in at 1/3 the thickness of the filter to get the correct back focus and perfect corner stars .. with the Esprit150ED you can screw your 2” filter into a thread on the telescope side of the extender .. this may mitigate your reflections but obviously makes it more difficult to change

A set of T2 Delrin spacers is only £11 .. thinking a bit more about it though when you change filters your back focus will change by 0.5mm which may give you wonky corner stars with one of the arrangements with an APSC sized sensor at f4.65... worth checking before committing.. you could move the camera rather than the guide camera with the spacer to adjust for correct back focus but then you'd need to sort both camera angle and guide calibration (although these would reset when you change back so you could use a bit of masking tape to align the camera and use different PHD2 profiles for the different guide camera orientations.. A bit of a faff though so same thickness filters and a guide scope would be simplest me thinks as you'll maintain back focus, won't lose subs from the other scope when this one focusses and will have far more guide stars to choose from.

Hi Adam... I gave myself this issue a few years ago by mistake, mono camera though with an EFW so had to change all the filters.. But I think you can do this (although I may have it the wrong way around).... with 2.5mm thick filter in place I'd put a 0.5mm spacer (ie 1/3rd of the filter thickness difference) on the OAG stalk to move the Guide camera out and focus .. when you change filters remove the spacer and it should still be in focus with the main camera (although in absolute terms out of focus so re-focus is necessary)... You'll have to redo guiding calibration when you change over as the orientation of the camera will change but on the Mesu that takes no time at all.. Dave

I used these for my 10" Meade .. they worked a treat ADM Losmandy-type Dovetail for Optical Tubes | First Light Optics Dave

Steve, I’d endorse @daz’s suggestion of using the NSG script to normalise the gradient in each sub to the ‘best’ one, you have to choose it by examining them in blink and subframe selector.. it usually turns out to be the one taken highest on the clearest moon free night. The script also weights them post normalisation and writes them into the image integration process.. I’ve found gradient removal on the subsequent master easier to do as the remaining gradient is much reduced and generally straight ( ie increasing linearly from side to side, top to bottom or diagonally) and features are more visible. A point in each corner but away from any feature (check with an image from a dark site) with DBE or APP light pollution removal ( which I find a bit better) then removes it .

It may be that its just not designed to work with the Atik which has 13 mm bf .. SX cameras have 16.5 or thereabouts.. There is an 8mm adapter on the back of the Esprit100 flattener but I’m not sure that even with that removed there’s enough distance to get a custom adapter in whilst moving the camera back the 3.5 mm required to get the OAG focused.. I certainly couldn’t find a way to get my Sx46, SX usb fw and OAG on my Esprit100.. the newer SX filter wheel with integral OAG may work as it’s designed for 55mm bf with SX cameras ..

I signed up to Telescope Live for four months earlier in the year to their Silver Subscription which was £30/month or so. This gave me access to quite a number (20 or so) of their Pro Data Sets (ie multiple hours per channel) as well as what they call One Click observations (which are maybe an hour or so per channel), I could have five One Clicks operating at the same time on multiple telescopes in Spain Chile and Australia and by doing the same target multiple times build up quite a lot of data on each target...... 70 of which remain untouched on my hard drive for when I've nothing else to do. Data quality was generally very good although not as issue free as you might imagine and I had to do my own sorting for focus star trailing and cloud (most scopes run unguided if I remember correctly)... after a while though processing it and producing images that looked just like everyone else's lost my interest and I left. I think that despite my approach to data capture being to programme targets in SGPro, turn it all on, open the dome and press go then watch telly or go out whilst keeping an eye on my ASC it's being able to choose my targets and the thrill of the chase that's important to me . That said I have been looking at Roboscopes recently having been very impressed with the images coming out of there... Best of all though would the the Esprit150 down in Spain (or France ) with a full frame camera on it... Dave

This topic has recently been discussed on the SX forum as a number of folk on there have been building their own jigs.. Terry Platts advice was ..... Generally speaking, you need to look for the bright spots that often are not aligned with the regular grid pattern... These offset spots are from the glass windows – the front camera window and the glass cover slip on the CCD package. As the cover slip is usually very nearly parallel to the CCD chip, it will give a bright spot, which is very close to one of the diffraction spots, so locate this and then align the front plate so that the diffraction spot closest to the cover slip spot doesn’t move when you rotate the camera. I'll remember this next time I do it.. Dave

Nice one Olly.. I assume that only the RGB is from the RASA...... the question on everyone's lips is how does the RASA ASI2600mc stack up against the Tak106/Atik 11000mono? Dave

No idea Pramod, but if they work on your system I'd suggest you try the ASCOM driver for ZWO cameras which allows two cameras you can download it from ZWO website . Dave

I've had similar problems with PCC plate solving recently ... when this happens I use the Image Solver in Image Analysis scripts.. this usually works ... then pick up the co-ordinates for PCC from the image