SteveNickolls

Yes, well done; nice round stars. Lots of keepers and at 40 seconds! Whatever you did with the mount is helping your images. I was sure you should be able to squeeze more seconds out of it. Ad Astra. Cheers, Steve

I wonder if that is a record for the most light frames taken for one image? Your resulting image is good :-) Cheers, Steve

Thanks for your idea, I like the use of velcro. I will have a trial just using velcro on the bracket and velcro on the adapter. I find the illuminator stays on the adapter it's the adapter that falls off the bracket :-) Cheers, Steve P.S. It works! Placing a short length of sticky velcro on either side of the bracket slot and the same on the adaptor and using the opposite type of sticky velcro to secure the bracket and adaptor together. Even holding the bracket upside down the light stays firmly in place :-)

I recall Joseph Ashley making that observation about Alt-Az imaging and certainly with my Startravel 102 being back-heavy has not done any harm in imaging, I think it helps damp down vibrations. Good luck. Cheers, Steve

Thanks for posting, your image shows the nebulosity well and you have good round stars. You mention being able to see the Milky Way though that will have been higher than where M45 was but you must have reasonable dark sky to help with signal v noise. Is there anything you can do to improve the exposure time beyond 19 seconds? I'm thinking of making sure the tripod is as rigid as it can be, maybe trying a weight in the eyepiece tray. Haven't used the Star Discovery mount but the older Alt-Az Synscan can yield 60-70 seconds of tracking with coaxing and at 60 seconds 100% can be 'keepers' so I'd think some extension of imaging time could be wrought out of it. Perhaps your mount is showing signs of struggling with the weight of the telescope and camera (must be headed for the maximun payload of 5kg)? These light weight mounts have a lot of flexure potential in their design being really made for observing not imaging. As for dark frames my view has come full circle over using them. Unless you take say x50 to complement your short light exposures you could be making things worse as Ian says. The time involved with taking x50 19 second dark frames amounts to just under 16 minutes so quite do-able in the field. I'd also advise taking x50 Bias and Flat frames to for stacking and see what improvement they also bring to the mix. Have you also tried switching off 'Live View' when ready to take images, it is said to help prevent the build up of glow in the lower left corner of Canon DSLR's as the sensor detects the stray heat as infra-red signal? Additionally the optical viewfinder can be taped over so no stray light seeps in that way and any red led on the body of the camera also taped over. Do keep posting your images. Cheers, Steve

Hi, the 600D has a greater number of pixels on the LCD screen (1,040k v 460k of the 1200D) and the LCD screen is vari-angle. Both use a DIGIC 4 processor I believe and both have 18Mpx sensors. The Canon 700D still has 18Mpx sensor but DIGIC 5 processor, touchscreen capability and vari-angle LCD screen. The 750D has 24.2 Mpx sensor, DIGIC 6 processor, vari-angle touchscreen LCD and wi-fi capability. Price obviously comes into consideration across the range. Cheers, Steve

That's a great looking image you have there-well done indeed. I don't use the software you do in processing. In StarTools there is a module called LENS to help remove coma and also the module called REPAIR. Cheers, Steve

No, but at 135mm the Samyang f/2.0 ED UMC is a great lens at f/2 with a cropped frame DSLR-http://www.lenstip.com/442.11-Lens_review-Samyang_135_mm_f_2.0_ED_UMC_Summary.html. It would be an excellent lens to use with the new SW AZ-GTi wi-fi model provided the mount can allow 30-60 second exposures or better (as can my existing Synscan Alt-Az model) since when compared to imaging at f/5.6 with f/2 you are hoovering up x8 more photons and can be almost as effective as 4-8 minute sub exposures. The new mount would be a great low cost, portable introduction to imaging with go-to and wireless remote control. Cheers, Steve

But it would be very encouraging if some enterprising soul did have a stab at imaging DSO's with it. An Alt-Az mount, 30-60 seconds exposures coupled with a fast f/2 lens could pull off wonders... Cheers, Steve

Hmm, after a bit of digging I'm intrigued wondering how much this advances from the Star Discovery AZ Go-To apart from the wi-fi capability. Against the older Synscan AZ Go-To the available data on motor resolution is better along with Freedom-Find ability and the wi-fi. Will the older Synscan mount be heading for the technological rest home? Regards, Steve

Oh yes...

Hi, So you are looking to emulate Curly Watts' attic observatory on Coronation Street? You will have very restricted views and suffer badly the effects of heat and turbulence from the house and roof. As for choice of Velux-no idea sorry. Do let us know how you get on. Cheers, Steve

Hi, I haven't a PoleMaster for polar alignment but use the polar scope that came with the SA mount and I'd advise polar aligning with your camera already attached to the mount so you don't knock or move the mount out of alignment when fitting the camera in the dark. A good tripod to hold the mount and equipment is essential. I never got on with the supplied wedge and prefer instead to mount my SA on a spare Celestron heavy duty alt-az tripod as it is then so easy to use the tripod controls to position Polaris quickly and accurately. Incidentally I've never had a problem subsequently adjusting the ball head holding the camera to point in the direction I want to image. With a ball head arrangement you don't have to loosen or tighten the mount clutch. Good luck experimenting. Cheers, Steve

What a cracking little mount the Star Adventurer (SA) is. I bought mine from FLO back in April (the astronomy bundle) and despite the weather have managed a few nights out under the stars. I found the mount well made but haven’t got on with the wedge preferring instead to have the SA on top of an old Celestron heavy duty alt-az tripod (set at 53 degrees for Nottingham) which makes polar alignment very quick and accurate using the manual adjustment controls. I found the wedge RA and DEC knobs very stiff to operate out the box and they needed silicone to smooth their working. I also obtained a right angled accessory to put on the eye end of the polar scope to make the alignment process a lot easier on the knees. The illuminated polar accessory is a fiddly beast to operate in the dark but I’m getting there. Also found that the SA/wedge will fit nicely on top of an old CG-5 tripod. I began taking exposures with my Canon 600D DSLR/35mm lens combination controlling through BYEOS and have been able to get 5 minute exposures with no star trailing. When I have left the cursor over a star when taking successive 5 minute exposures hardly any movement is seen after 10 minutes. Really looking forward to using the SA with longer FL lenses and counterweight in the new imaging season and on holiday. Cheers, Steve

Thanks for the link to the discussion on the D80 Ds-Pro, it sounds very useful. Have you tried StarTools for your image processing? You can try it for free though you can't save images unless you later decide to purchase. Ivo is a very helpful person and you can read more here-http://forum.startools.org/viewforum.php?f=3 and there's a long video in The Astro Imaging Channel you could watch-http://forum.startools.org/viewforum.php?f=3 Cheers, Steve

Hi, and thanks for posting. You might want to get a copy of, 'Astro-photography on the Go-Using Short Exposures with Light Mounts' by Joseph Ashley, available from the SGL's sponsors. A very worthwhile read on the whole subject. As The Admiral pointed out you are witnessing the effects of field rotation and some mount movement, the book has a field rotation table identifying the maximum exposures of objects at different positions in the night sky, basically longer for objects in the East and West and at lower altitudes. I'm interested too at the performance of your telescope, do you find there's light aberration, particularly blue fringing (certainly not judging by your image)? The D80 Ds-Pro sounds excellent value at £349. Cheers, Steve

Hi Fabien, Thanks for your reply. No that's fine thanks, just me being idle I guess :-) I'm hoping to do more in the future with camera and lens and seeing the outcome of images at say 200mm FL is very helpful and inspirational. Cheers, Steve

Hi Fabien, Thanks for posting your latest image, well done there :-) Can I enquire as to the equipment used, settings etc. and any filters employed? I'd like to have an attempt at imaging that area of sky before it is totally out of my view but that's down to the weather which isn't co-operating at all this year. Good luck too with further imaging. Cheers, Steve

As regards which ISO to use if you experiment using different ISO settings when imaging you will come to some workable conclusion to best fit your own equipment and imaging location. The link Uranium235 gives is most interesting. I've also found www.sensorgen.info useful too. During my short stint astro-imaging so far under bad suburban skies I have gone from using ISO 1600 to 800 and to now 400 with my Canon 600D, the last drop albeit when using EQ tracking as I can get longer exposures than when using my Alt-Az mount and in combination with fast lenses (can be down to f/2) really hoover up those photons and when having more dynamic range left available is important. With my Canon 600D Sensorgen indicates that by coming down from ISO 1600 to 400 the pixel well saturation point increases from 2001e- to 7578e- while dynamic range increases from 9.4 to 10.7 Using a higher ISO setting you are really just making the image brighter, there's no more detail and will sacrifice the dynamic range when later processing the image. Good luck experimenting, it's very much part of the fun. Cheers, Steve

Yes well done. Interesting to know what objects will look like at various FL's. Cheers, Steve

Yes, and a lot of Alt-Az work can be done at 30 second exposures too. Good luck anyone though having a try. Cheers, Steve

Yes, the season is about ending for me, chalk it mostly down to experience with such poor weather of late. I'm hoping come the autumn we will get much more favorable weather conditions. Good luck anyone trying to image into May-June. Cheers, Steve

And don't forget you also captured M101! Cheers, Steve