michael.h.f.wilkinson

Years ago, I built a little 4.5" f=500 mm mini-Dobson for the kids. It worked quite well, but was always a bit of a pain to collimate because the primary mirror had no centre spot. I got a Cat's Eye centre spot from FLO and fitted it to the mirror. It is now very easy to collimate, and a brief test on the moon in daylight gave quite a good image, even at 125x magnification. The 6x30mm RACI finder also makes life a lot easier. As the kids are no longer interested, I will probably donate it to the local Blaauw Observatory for outreach.

I spotted OJ-287 at mag 13.8 with my 8" SCT, so a 10" scope should work

Must get ready for this one. A planet in opposition in autumn is something haven't really had lately

I have spotted it a few years ago when it was about mag 13.8. Most distant object I have ever spotted at an estimated 3.5 billion light years away.

Very nice result

Welcome to SGL, Karen. Even with binoculars or a birding scope, you can see lots of interesting stuff.

This seems to be better, but I still feel the southern part is better than the northen

Just ran it through Astrometry.net, and it picked up just a couple of galaxies

I decided to go for the APM 80mm F/6 triplet with 0.8x focal reducer, rather than the Meade SN6. This makes tracking a lot easier, and grabs a wider field. I therefore went for the M86 end of Markarian's Chain, with M87 fitting into the lower left of the image. Conditions weren't great, with some high haze, and clouds limiting the run to 2 h of data. This is the result of 120 60 s subs, with 30 darks, 50 flats, 50 dark flats, and 50 bias frames. Still noisy, so I should add more data if I get a chance. I think the distance of reducer to chip isn't quite right either, so will have to work on that.

You are right, I wonder if the chip was truly square on the optical path. I have some other stacks of the same data. But first get the DSO imaging working.

I set up my APM 80mm F/6 triplet on the GP-DX mount for a session on deep sky, but decided to snap the moon with the ASI183MC and a Meade 2x TeleXtender in place. Stacked 250 out of 2000 frames with AS!3, sharpened using ImPPG, final tweaks in GIMP Well worth a click for full size.

Seeing is almost always worst in Ca-K, I find. Usually seeing is better in the morning, however. Note that I have a straight through Ca-K module, which is easier when imaging.

Lo and behold, a little AR is visible on the sun. Grabbed the APM 80 mm F/6, inserted Lunt wedge and started imaging in white light. First up, full disk images: WL, grey scale: WL, pseudo colour: Then a detail shot with a 2.5x PowerMate inserted: Not much to look at, but hey we have some activity. Next, Ca-K full disk images: Ca-K grey scale: Ca-K, pseudo colour: Ca-K part inverted: Ca-K, part inverted + pseudo colour: Some proms faintly visible, but not much to look at

I have two cats. In the background you can see th Trusty old Celestron C8 on Vixen Great Polaris mount. I usually have a 14x70 finder scope attached to it as well. It is my main visual and planetary imaging scope. I have had it for nearly 25 years, so it must be doing something right. In foreground you can see my Meade SN6 6"F/5 Schmidt-Newton on a Vixen GP-DX mount. It has become my main comet sweeper and DSO imaging scope. Got this OTA for just €165 second-hand in January 2020. Just some imaging results: Jupiter with the C8 DSOs with the SN6 Leo Triplet M101 M13 I think I will hang on to these scopes for a while.

I think it should be (503) Evelyn. Thanks!! Confirmed that here https://in-the-sky.org/findercharts.php?startday=1&startmonth=4&startyear=2020&duration=5&objtype=0&objtxt=&objs=26530 It is a mag 13.7 object

A single streak in one sub would have been removed by sigma clipping (several satellite trails were removed, I am sure). The subs were stacked in APP weighted by quality, and as NGC 2903 got lower in the sky, the quality got worse, hence the tapering, I guess. I didn't manage in Stellarium, I will give CdC a shot

I took this photo of NGC 2903 between 22:45 CEST on April 20, and 0:54 CEST on April 21, 2020. On the left, there is a clear trail of an asteroid, similar to the track of asteroid Vaticana in an image I took of the Pleiades some time back. The length is about twice that of Vaticana in the M45 image, shown for comparison below. Duration of capture was the same, but the NGC 2903 image was taken at twice the focal length, so I guess the trail is left by a main belt asteroid. I tried find it on this site, but no luck with any of the objects listed in Leo. Any ideas how to find which one this is?

Very nice indeed. I am thinking of going for this region with my 6" F/5 one of these days

I am bickering much more with the mount than with the Schmidt Newton's collimation, I find I really need to get a permanent set-up

I have captured M51 with my 80mm F/6 scope and ASI178MM camera, and got some pretty decent results at 480mm focal length This was just an hour or so of L data. The small pixels of the ASI178MM do help in this case. I do prefer the result I am getting on galaxies at the longer focal lenght of the Meade 6" F/5 Schmidt-Newton at 762mm focal length.

For a "grand" total of 1 h 38 m 30 s. Didn't add a huge amount of extra data, but improved the area around NGC 6207. Also managed to reduce some gradients to the lower right of the cluster in my previous image. This is getting somewhere.

Very nice, it surprising how even smaller scopes with shortish exposures can capture mag 15 supernovae. I managed this one in just 33 minutes with a 6" scope This is just a crop

I used a Meade 6" F/5 Schmidt-Newton with ASI183MC. It consists of no fewer than 361 subs of only 15 s, due to issues with tracking. APT and PHD2 won't connect to the GP-DX mount, because somehow the ASCOM platform does get permission to access the COM3 port.

Thanks, that might take a while, the forecast isn't great the coming nights

Got 1.5 hours of data on these targets, but quite pleased how they came out. The Meade SN6 and ASI183MC frame these nicely As ever, more data are needed. I also need to sort out guiding, as tracking errors remain visible