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Skywatcher 80 ED DS-Pro outfit including matched flattener and motor focus. Now only £350
This kit gives you a great introduction to astronomy and imaging, which is why it's so popular. You can see details over at FLO but there is:
80 ED Ds-Pro OTA (Objective Lens Diameter: 80mm, Telescope Focal Length: 600mm, f/7.5)
SW Eyepiece (2"): 28mm
2”/50.8mm Di-Electric Star Diagonal
Dual-Speed 11:1 2” Crayford Focuser (Backlash-Free)
Supplied with Tube Rings & Mounting Plate - please note there is a longer black vixen type dovetail fitted, not the fancy new green short one you will see on the FLO site
SW motor focus and fitting kit - I've never used this, hence it's not fitted (more details over on FLO)
Dedicated SW 0.85x reducer/flattener (see FLO for more details)
Aluminium Carrying / Shipping Case
The RRP is over £720, so grab a bargain while you can.
Collection from Nottingham, or DHL for £20 (within UK)
By Ships and Stars
Last night was the best night of astronomy I've had in my short time delving into this passion. It was simply incredible. Fortunately my dear friends the midgies have departed Scotland for another season. This means I can now stand at the scope without ingesting a lungful of tiny biting insects and concentrate on what I am observing. Always a plus!
Two nights ago I went to my local dark spot with my 200p SW reflector. It was wonderful. LP map shows Bortle 4, but I would actually say it was a 3 or possibly a 'bright 2' when the lights go down a bit in the wee hours.
Last night, I took the 20" dob and parked up. I am finding it easier and easier to move this beast around, but it's still a little bit of work to set up at the end of the day (literally). It can't all be so easy!
I'm fairly new to astronomy and my scopes haven't seen a huge amount of use. After several failed attempts to get the GOTO working, I finally sussed it last night. It was just a few simple things really - small errors on my part such as a misplaced washer which blocked the azimuth from using its full range of motion, combined with a limited view at home which prevented me from doing a successful align. A huge relief to get the GOTO up and running, but I now feel a bit like I'm cheating!
I don't feel guilty enough to not use the GOTO however😁 Frankly, it's brilliant and was putting objects bang in the centre of the EP.
I arrived about 6pm yesterday so plenty of time to set up. I left my counterweights at home and thus ended up strapping a small vinyl bag of tools and tyre jack to the underside of the mirror box with a tie-down. Worked really well actually! Can fine tune by removing a spanner or two.
A few drops of rain blew through just before dusk but then rapidly cleared off, so all systems go.
I tripped over the power cord after my first successful align. And then did it again a minute later after my second align! Will need to tidy that arrangement up or put some of my glow tape on the cable. Plenty of practice then doing an alignment, haha.
M57 Ring Nebula for starters, I've been playing with my Baader 36mm aspheric quite a lot lately, I like the wide views. The Ring was fairly small through the 36mm but bright and crisply defined with an apparent faint blue tint. I then swapped to the 21mm Ethos and OIII which stayed in the focuser most of the night.
Next stop was NGC6960, Western Veil Nebula or 'Witch's Broom Nebula' which was mind-blowing. It appeared as a silvery apparition which threaded right across the sky and extended well past the FOV from the 21mm Ethos. Scanning along its wispy tentacles was amazing. There's something unnerving about viewing it, it gives me goose-pimples, just otherworldly. The Eastern Veil and Pickering's Triangle in the central area were also clearly prominent, albeit slightly less luminous than 6960. The Veil was also clearly visible without the OIII, but with much more 'background noise', i.e. stars competing for attention.
Following this, I slewed over to the Cocoon Nebula, but only saw a very dark lane practically void of stars. That was interesting in itself as it was so apparent by virtue of its darkness.. I don't know if I bumped the scope alignment of if I was just too impatient to punch another object in to the handset, but didn't spend a huge amount of time chasing it. In hindsight, I think I slewed to the wrong end of the dark lane. I'll find it next go.
I then lined up on the Crescent Nebula which was easily visible, lots of fine filamentary details observable after some time studying it. A beauty.
Next was Dumbbell Nebula which practically looked 3D through the big dob, just jumped right out at me. Another simply amazing sight. I spent quite a long time staring at it and could easily see the entire shape and structure extending from the 'Apple Core'. I remarked last night it looked like it was hanging inches in front of the scope. That's sheer aperture working I suppose!
At the end, I spent some time just slewing around and having a mesmerising look across the sky, just taking in the depth and variable magnitude of stars that a big scope can display. I was already running on three hours' sleep from the previous night and by this time, I was starting to crash but was on a natural high. I crashed into the bed happily.
Can't wait for another clear night with the big dob. I was a bit worried a few weeks ago that I'd bought something I didn't have the time or skill to fully appreciate, but getting the GOTO up and running and being able to rapidly slew to various objects really put things into perspective. My 200p is a wonderful, portable scope, but in comparison, 20" of aperture is simply a completely different level. It is like the difference between a small grainy 640px video and high definition 4k with the brightness cranked right up.
Tonight I shall stay in, sleep well and dream about how much discarded glass is needed to cast a 36" mirror blank and how many years it would take me to figure it...
Clear skies all
It's an ED80 with the stock focuser. I think there is some astigmatism somewhere as my stars can be a little stretched and so I want to see if I can use a collimating laser to check if the focuser is in straight. (I'm also going to make a determined effort to get the spacing right between the FF//FR and the sensor, but that's another story). I can't see any threads that get into the detail of lining up the focuser with a laser.
If I put the laser in with the target bit facing up, then the red dot that bounces back off of the lens is slightly off centre on the target on the collimator. If I loosen the screws, turn through 90deg, retighten and look again, then the red dot is in a different place and so on all the way through 360 deg. I'm thinking that the red dot should be central (as when collimating a Dob that I used to have). Is that right?
It may be that the laser needs collimating, but I'm not sure how to do that.
Any advice on whether this approach is going to get me anywhere would be appreciated.
I scrapped all the Oiii and Sii data I previously took during a full moon (about 15 hours worth) and retook it all when the moon was a bit smaller at 76%. Ha was taken during 98% and 67% moon. All the lights were taken on the following nights: 12th, 19th and 20th September 2019.
Integration times, all in 600s subs unbinned:
Ha = 28.33 hours
Oiii= = 5.67 hours
Sii = 5.67 hours
The Ha data is really nice, and unsurprisingly the Oiii and Sii is not as strong (or nice).
I'm missing that (vital) step in my processing routine of getting the Sii and Oiii properly stretched to match the Ha, before combining. I dont really know how to deal with the weaker data properly. Any pointers would be appreciated.
What I do currently:
All the data is loaded into APP into separate channels/sessions.
The data is stacked and registered against the best Ha sub
This produces individual stacks of Ha, Sii and Oiii that are all registered
Each channel is processed with DPP in APP and then saved as a 16bit TIFF
Each is opened in PS
Stars removed with AA and any remnants removed and tidied up
I then open a blank RGB document in PS
I paste Ha into Green, Sii into Red and Oiii into Blue
Adjust the selective colour settings to get 'Hubble palette'
Adjust levels, curves, saturation until looks ok
All the Ha Sii Oiii data is then combined together in a single 'super' stack in APP using quality weighted algorithm to create a 'luminance'
That luminance layer is adjusted using levels, curves, and NC tools such as local contrast enhancement and deep space noise reduction (using masks to apply as required)
The luminance is pasted onto the above colour layer, and incrementally added using gaussian blur
Cropped and saved.
Here it is anyway I haven't intended on any more exposure time for this one, but will consider it, if the expert opinion dictates otherwise!
Hi to everyone, I used to do some astrophotography in the past with a Celestron AVX and DSLR but after few month had to give up for several reasons, including light pollution (I'm living in zone 3 east London), and also working shifts. Now I want to start again, and this time more serious. I've been searching around for a couple of months to choose all the gear and I'm quite happy with the list so far although it's a bit over the price I planned at first.
I will get an William optics Z73 with his 50mm guide scope, a flattener/reducer 0.8, light pollution filter IDAS D2 and as camera I will use a Canon 600D modded and I will buy a ZWO 183MC Pro, after so much research, I'm very happy with the scale and framing I will get with this combo, but I'm starting to get confused with the mount.
My first idea was to go for an HEQ5 Pro, as my previous experience with the AVX has been awful, then I realized that the FLO, sells that mount with belt modification and also some cleaning and tuning if required, I heard that it's a big improvement over the stock one and the price it's ok, but another important factor for me it's portability. Unfortunately, my garden doesn't allow me to do much so I will need to carry around on trolley, for a km walk, I'm a strong person and been doing plenty of time with the AVX, so my confusion came recently when the iOptron mounts entered my radar. I start comparing the heq5 pro with belt, with the iOptron cem25EC and the CEM40 without encoders, and I'm so unsure of which to buy, the cem25 seem to be the equivalent of heq5 at least speaking of payload, but in some threads I read people saying it's a bit fragile so kind of remove it from the equation although the weight it's interesting for my situation, then the cem40, seem to be quite similar on weight to the heq5 but with higher payload and that's interesting too as I will buy a C11 at some point.
Now it will all come down to the accuracy of tracking I guess, how the heq5 and cem40 would compare on tracking and guiding? If the cem40 it's better, I would probably go with that since it holds more and would last longer as I don't plan to get anything bigger than a C11, but if the skywatcher it's better, I could decide to go for that, and when I move to a place with better garden then get a second mount with higher payload.
Apologise for the long post and my english.