DaveS

Crikey that's a compact group. Just had a look on Stellarium, shows the position but no pictures. Gonna need a bigger 'scope.

Got mine this morning.

As Carole says, once you have the subs rolling in there's plenty of time for visual, it's what I do even under my only so-so dark skies.

Don't waste precious imaging time.

I'll add that turning the camera by 90 deg as was suggested above is a non-trivial operation involving rotating the entire focusing train in its seating on the back of the ODK then rebalancing around the RA and OTA. ASA mounts are *very* finicky about balance in all three axes. The focuser doesn't have a camera rotator (Despite being a FT), and I'm still looking for a 68 mm rotator.

Edit: I did find a pair of Baader quick release dovetail adaptors but they are £243 together, and eat 25mm of  already tight back focus.

Unfortunately £600 is more than I want to spend on a mobile mount that might only get used at star camps, so I'm out.

Take Two.

Shifted the centre so I now have NGC 3590 and possibly the very distant cluster that @wimvb mentioned.

BUT...

The sky background is so bright that I really had to hammer it down. My fault, as I was setting up in a hurry since the sky had cleared just as I was going to bed and just grabbed a likely exposure file, and decided to live with the 600 sec subs. If I had more time I would have set up one with 300 sec. Far too much moon for 600 sec.

Options: Use a camera with a bigger sensor, IMX 455 to get more FOV, Yeah right, like I have a spare £5k or so. Or use a camera with a smaller FOV ASI 533C and just go after the HCG with nothing else. Probably a no-brainer.

@ollypenrice makes a very good point about the software, and to that end I'm going to make a shout out for AstroArt, currently in V8. I think it's been unfairly overlooked in the mad rush for the latest flavour of the month. It's your one-stop-shop for capture with sequencing, plate-solving, guiding and autofocus, Then when you've got your data it has a blazingly fast stacking, that will also stack comets and spectra, plus the processing tools have had a huge upgrade, even from V7, and are now deceptively powerful.

I have also tried PixInsight, which did my head in, and Star Tools, which I couldn't get on with.

I'm not saying that it will necessarily be the choice that you get on with best, just don't forget about it, it's worth a look.

Although I'm a strictly mono imager (For the time being) I concur that OSC is the best option as a wheel plus a full set of filters could eat a significant part of your budget.

Regarding going off site for imaging, will it be a quick "there and back in a night" or will you be camping, perhaps for a few days? If it's a one night stand then you will need something that can be set up and aligned quickly so as not to eat into imaging time, whereas if you're planning mabe 2-3 days then it's not quite so rushed.

As for "Future Proofing" no mount short of a Mesu (Which would eat you whole budget, and more) can be considered future proof, but the EQ6-R should do you for quite a long time.

I would definitely go for a triplet apo with flattener / reducer or one of the quintuplet astrographs from Sharpster (Disclaimer: I have no experience of the latter, just throwing it out as a suggestion), as any kind of reflector probably won't take kindly to being bounced around in a van, and will need re-collimating once you get to your remote site.

Also I would not break down the imaging train between trips unless maintenance is needed, because unlike the visual guys we're not constantly chopping and changing. It's hard enough to get everything playing nicely together, so once it's working, Leave It Alone.

That's my bit for th emo, I may have ideas to add later.

AP is a money pit that can swallow £5k without even a burp. I would be thinking an apo 'frac, an APS C CMOS and possibly LRGB filters, at least for the time being. From what Olly has said (And he should know) the Tak FS60CB is a very poor choice for AP with a worrying amount of blue bloat.

I think, from your other thread, that you already have an HEQ5, which would go nearly £k towards your goal.

I know it's silly to make astro plans with our rubbish climate, but I *may* start looking at the Hickson Compact Groups. My G3 16200 is a bit wide, even on the ODK 12, but an ASI 533 Might be doable, even with the ludicrous 0.39"/ps plate scale. I could also use it with my Leitz lenses for the mobile widefield setup.

4 hours ago, tomato said:

Just out of interest, here is a sort of (unscientific) side by side comparison of CCD vs CMOS, M33 taken with the same scope from the same location:

Esprit 150/Moravian G2-8300 mono LRGB 160 mins

Esprit 150/IMX 571 CMOS OSC 210 mins:

I actually prefer the CCD image…

 

The proof of the pudding as they say. CCD wins.

30 minutes ago, bosun21 said:

The pound equivalent for $640 is £490. Well that’s according to my browser conversion 

The formal exchange rate has never featured in price conversion from US to UK. Easier (And more profitable) to use 1:1

Cynical? Me? Yep, damn right .

So about £650, applying the usual $:£ ratio of 1:1, plus. That's quite a lot more than either a standard SA or AZ-GTi, puts it in EQ3 / basic EQ5 territory. Don't think it will fly at those prices. I was hoping for something the right side of £500.

With our climate, probably not.

As an aside, I checked on Stellarium, and those two searchlights blazing away are mag 7.15 and 8.15 . Most of the galaxies are around mag 13 or so.

A lot of fine detail there, a few more hours data will clear up some of the noise.

13 hours ago, Stefek said:

Well , every task requires appropriate tools . I tried all 3 types. Have Altair fan cooled 178c, using it for planetary . Of course, fan can't cool it below ambient , but keeps the temperature at ambient or around.  It does not add anything much to the image quality so I removed it. 

Was also using Nikon, after a while usb connector became a bit loose, had to add additional 9V power supply (DC/DC converter) , clip in filters are more expensive... removing IR filter expensive again cost something,...

At the end, got myself proper cooled astro camera .... so again the tool for the task. 

 

 

"The right tool for the job" sums it up perfectly. Yes you can bodge out images with a modded DSLR or even a fan cooled camera, but it's a bit like asking Grinling Gibbons to carve an alter screen using a sharpened screwdriver  (I know they didn't have screwdrivers in the 17th century) instead of a finely honed chisel.

I use AstroArt 8. I think my processing of individual stacks is a habit that dates from earlier versions, before the DDP routine became more versatile. The latest DDP has much more control, so I think I will adopt the RGB combination *then* stack in future.

8 metres would be a stretch for unpowered USB, but ethernet will have no problems.

Another rework, this time the Coma Cluster in LRGB using new Luminance calibration, and a different stretching, Using from the RGB stack rather than stretching the individual stacks.

I think I've managed to hold on to bore of the blue in the spirals than I had before.

I guess this is one for @tomato 😄

Yes, peltier cooled every time. If you buy a camera that's only fan cooled you'll soon be thinking "what if...", and "If only..."

Having obtained new Luminance Flats and Dark Flats I had a rework of this, also using a different way of stretching the RGB, using a DDP on an already combined RGB image rather than stretching each stack separately.

Could always do with more data, plus some good H-alpha.

OK, as promised:

Stack without Flats. Given a slightly exaggerated stretch

And the Luminance Flats, calibrated with Dark Flats

The filter looks off-centre, don't know why . Not a cheap wheel.

Dur...That's HCG 44, which I had been working on. Still, it shows the problems.

I did a trial stack without Flats, and a stack of the Flats last night, but didn't get round to posting, will put them up this morning.

OK, I'll try that, thanks. I'm using T-Shirt flats with either a completely blue or light overcast sky.