mackiedlm

I'm not sure if I've seen him on here. Did you mail him deirectly or via the wenbsite - because i think he was having some problms with not receiving messages sent from the "contact me" page of the website. But whenever I used him he was very responsive.

This is first light for my new Sharpstar EDPH II after the disater of trying too close to the moon a couple of weeks ago At this time of year it had to be orion but I wanted something different to M42 and the Horsehead so poking about on Stellarium I found that this pairing fitted nicely. I could get Horsehead, Flame, M78 and enough of Barnards loop to see the curve so thats how I set it up. I knew from the start I'd only get a very short window before clouds came in ( otherwise I'd have been on the witches head) and it turned out that I got onl 1 hr 45 mins. So this was; Sharpstar 61 EDPH II, ASI 2600mc, L-Pro filter. 35 x 180s I have darkened it down a shade because for some reason my posts on SGL always look brighter than anywhere else. Struggled get rid of a gradient in PI without losing faint HA so i tried in APP - kept some HA but at the expense of dark dust. It may need another mm or so of backspace but I'm very happy with the scope.

Another stunner Richard. You did well getting 4.5 hrs. I was out that night and got 1hr 45.

I had Juan at https://cheapastrophotography.com modify an 1100D and also bought a modded 700D from him His support, help and service is absolutely first rate and I would highly recommend. My 1100d works perfectly well but is a little noisy. The 700D is great but it does (unusually for a DSLR) exhibit some amp glow. This is a known issue with the 700D and once you know about it it is easily dealt with in calibration. I have seen lots of great images with the 600D (I believe its the same sensor as the 700D) and have not seen any reference to the amp glow with it But contact Juan and get his advice - he is really helpful.

Thats a super image for just 1 1/4 hr data. Very nice!

Thanks Dave, when I do that having measured the donut in PI I get a distance of around 11mm - which actually makes sense if the dust is on the camera window - NOT the filter. The 17.5 is to the front of the tilt plate and the window is set back some mm from the tilt plate. No the drawer only goes in one way and there is only one thread on the filter so no way to muck it up - or else I surely would!!

Hi Olly and others, so I went home and checked the filter drawer and it was rock solid, I could not see anyway it had moved. I then made a stack but without calibration frames (no flats or darks) and the dark arcs are present (infact they are darker than the bunnies) in the light subs before calibration - so are not infact related to the flats or the calibration. (Sorry, I probably should have done this earlier.) This is the uncalibrated stack, heavily stretched and stars removed as it shows up the abberations so much better And this is the master flat which I have adjusted to try to bring out the dust and the vignetting I then checked in stellarium and when the lights were taken the bright full moon was to the right and just below centre of the light image. It was only about 45 degrees from the target. I think this probably accounts for the heavy dark shadow on the right - cast by the dew shield. Yes there is some vignetting in the flat but not nearly as bad and it does not match the shadow on the image which is lighter at top/heavier at bottom. My conclusions, but I'd really appreciate a sanity check from those of you who know better than me, are; These dark arcs are a result of the bright full moon, relatively close to the FOV This uneven bright illumination has resulted in the deep shadow (vignette) to right of image and by some type of reflection abberation, to the dark arcs which correlate with the edge of the dust bunnie furthest from the direction of illumination. The L-enhance flter is probably the physical location of the dust (ses this sound right according to the size of the bunnies??) The L-enhance filter with its highly reflective surface may be causing/adding to the effect The fact that no dark arcs are present in the flats is telling me that the issue is not intrinsic to the scope itself i.e the optics of the scope are not at fault. (This is really important because its a new scope and if there is a potential optics issue i should be informing the supplier right now rather than wait for later confirmation - it will likely be weeks before I get out again). Thanks for all your help. David

Thanks so much for doing that Olly. I can see exactly what you are getting at. As I said to Dave above, the drawer was taped in to avoid light leak but I did send the scope to park remotely (via my tablet from my bed!!) so there has to be the possibility that it moved during that skew. Although I did go down and run the flats immediately, I didnt think to check the filter drawer. If we take the image width as being equal to the sensor width (25mm), then I'd calculate that offset as being less than 1 mm movement of the filter drawer. The rig is still set up exactly as I left it this morning so I'll take a look when I get home. Its about the only thing thats making any sense at the moment. I'll report back. Thanks again. David.

Good idea. They are not so easy to see in the individual subs but they are there and are not moving around.

Thanks Dave and @carastro but no, the clouds did not lift till nearly nine so it was past meridian by that stage.

Thanks Dave, yes I see how that could happen. But the filter is in the drawer, screwed tight and, because I worry about light leak, the drawer is then taped shut with electricians tape so I cant really see that. I'll check everything is tight but all I did from last light to first flat was park the scope - so I'm struggling to see that either. And yes thats what I'm thinking of doing. I got rid of the worst gradients in APP, (PI failed miserably!) but its still not great.

Just for completeness this is a single light but stretched further than the images above just to see whats going on.

Thanks Olly, So below is a master flat, a single flat and the full integration (this is out of APP because I ran the data through that too see if it calibrated differently - it didnt!!) I've tried to screengrab them at the same size to allow for comparison of location and you can see that the marks on the integration correlate closely to the left circumference of a dust mote. They are not exact line ups, rather the marks in the final are offset to the left of the dustmote and the calibration has done a fairly good job on the rest of the dust mote. On the left hand side where the image is darker I dont see any of the marks but that may just be because the background is darker. single flat Masterflat Final

Thanks Wim, but if you look at the lights and the flats youll see that the curves are concentric to the dust motes. Also, they dont show up as separate moving lines in sequential lights. its only the dust bunnies that show. So what seems to be happening is that most of the dust mote is being calibrated out leaving only part of the circumference of the original mote. I appreciate your help.

I had first light with my new Sharpstar 61EDPH II last night and have a problem with the integration in that there are curved lines showing over the image. Marked for clarity These are screengrabs of the autostreched masterlight straight out of WPBB (fully integrated in Pixinsight with flats, dark flats and a master dark) When I inspect the flats and masterflat, it is clear that these curved marks are associated with dust bunnies but they do not seem to exactly line up with the bunnies in the lights and therefore have not been properly corrected. Capture details Sharpstar 61 EDPHII (275mm) ASI2600MC pro, 2" L-enhance placed in a ZWO Filter holder (taped up to ensure no light leak), Flats were taken using APT's CCD flat tool, with ADU targeted at 35000 - led flat panel in front of several layers of white fabric (used on many occasions with my 80 ED with no such issues). Flats were taken immediately after the imaging session without moving the scope or changing the optical train. My current thinking is that the moon was very bright, I was probably too close to the moon for the L-enhance, and that some type of reflection or shading has happened to make the dust bunnies larger in the lights than in the flats. There are also wicked gradients that I cant seem to tame. I have put the master light, master flat, master dark together with a couple of single subs, single flats and single dark flats into this folder if anyone would like to look at them to help me diagnose why this has happened and if there is a way to resolve it (new flats taken a different way?) https://1drv.ms/u/s!...X_qGmi?e=NDOaCH If taking new flats will not fix this is there any to fix this in processing. Thanks for any help.

Back focus is only an issue once you add the ff/fr. Its the reducer that has a set back focus. Until then you will be able to focus just by moving the focus knob.

That's a beauty! Great star colors and balanced nebulosity

If its tonight/tomorrow moon is pretty close to Orion so I'd for sure use the filter.. On this target you can still get a good colour result even with the l-enhance and if you have 3 hours of OSC RGB you can easily put the coloured stars in on top which will really help it look natural (wahatever that is in AP) This was mine done a year ago at 94% moon, L-enhance, no RGB stars unfortunately.

With Galaxy season fast approching I decided to get the old 8" LX200 and its wedge out and get it ready. Clouds and technical issues meant it ended up at just over 3 hrs. Bad seeing/guiding/balance resulted in some star elongation but i'm fairly happy with it overall. This is 65 X 180s, Canon 700d (ISO 800), 8" LX200 GPS, Skywatcher 0.85 FF/FR - (FL from platesolve 1970mm) NEQ6 (No filters) C&C Welcome

That is a truly fantastic image. So much of the backrounf HA showing through.

Thanks Steve @FLO But, everyone, can I kindly request that this thread does not become another tit for tat about the relevant merits or otherwise of the various brands. If you must do that can you start another thread please. Can we please keep this one on the topic of hands on experience with the Altair 26M. if there is none then thats fine too. Thank you.

If I wanted to hear comparisons of the three thats the question I would have asked. If I wanted to save money thats what I would have asked. What I want is to hear if anyone has hands on experience with the Altair 26M, that therefore is the question I asked. If no one has that and I therefore get no feedback on hands on experience with the Altair 26 M then that itself answers the question. I had already done the search on Astrobin and seen that image and a few others. I have done much research and digging and now what I want to know is how the Altair 26M performs in the hands of people who have one. Thats all.

Why would you do that? The reason I said that is that those discussions have already been had over and over in other threads and I dont want this one to go that way with 3 pages people arguing it is or is not the same. I just want to hear if anyone has hands on experience with the Altair 26M

Does anyone have hands on experience with the Altair 26M camera. (Please note I'm only interested to hear about the Altair version, not the ZWO, Rising Cam or others and only the Mono - not the colour version) Thanks for any feedback you can provide. David

These are great images Lee. The top one is really fantastic.