powerlord

20 minutes ago, alacant said:

I believe some (most?) of his reviews are nonsense. 

HTH

ah. thanks - good to know.

still, concensus (well nearly) seems to be don't bother  - just use bias + flat. So that'll do for me frankly. I ain't a pixel peeper - as Lazy Geek on youtube would say.

I do find the ASIAIR routine a bit onerous. I'm hoping with a bit of experience to note a correlation between what it's trying to achieve and the liveview in the DSLR - then I can use the liveview (maybe if I check the polaris position first, then note where the clock face is on the screen, etc.. draw it on with a marker..) . The lack of real time feedback is the main issue with ASIAIR imho. You're setting maybe 5 second exposure, then it has to download it over USB2, then another couple of seconds to process the raw and display it. not quite sure if that includes your change or not, so you wait for it to refresh again, then repeat again and again and again. oh you've went by it.. so back we go again... arggggg. synscan was soooo much easier with liveview and 'centre it in the view' buisness. I may end up using syncscan do PA first, then start ASIAIR, but that would be admitting defeat!

stu

1 minute ago, Alien 13 said:

What makes you think the tray is anywhere near level 😋

Alan

as i say - turtles all the way down. 🤪

19 minutes ago, Stu said:

This ^^^^

Unless you want to do the project just for your own satisfaction (which is a perfectly valid reason, of course), then it is a waste of time. A standard spirit level will get you well within the accuracy needed, actually, so long as your PA is accurate, whether the tripod is level or not is completely irrelevant. All it does is ensure there is no or minimal interaction between the az and alt adjustments for PA.

I have to disagree with you there - as you say yourself in the final sentence. Once it's PAed it is, fair enough - but PAing is hard enough in ASIAIR without me having to worry about ALT offset changing when I change the AZ offset. The closer I can get it before I start, the quicker my PAing will be - especially as my old EQ5 is a bit rough with ALT in the first place. It's a heck of a lot  easier if the two can be corrected independently imho. Standing there for 20+ mins fannying around trying to get it PAed is not my idea of fun. Anything that can make that quicker I'd gladly do.

However, see above - the glaringly obvious sitting the phone on the tray will be my goto next time - embarresssed I never thought og that - I'll been trying to sit in on a square corner of the mount... sheesh.

stu

42 minutes ago, bottletopburly said:

Jut use a mobile phones built in  digital level ,lay it on the tray under mount  or buy a better larger bubble https://www.amazon.co.uk/Acrylic-Spirit-Bubble-Diameter-Degrees/dp/B00KP8YNJG/ref=pd_sbs_7?pd_rd_w=JymT2&pf_rd_p=448c740b-5b83-47fd-809b-6bedb049b25c&pf_rd_r=2MSMJZ39R0YTG0AAR367&pd_rd_r=39c08d12-2ae4-45fa-8c6f-58d2628fb9d7&pd_rd_wg=rijxg&pd_rd_i=B00KP8YNJG&psc=1 

you know I'm happy to admit when I've missed the obvious - I have never thought of just sticking it on the tray!

Hi chaps,

Before I set off on another project - I want to check if something exists for this first.

Problem : levelling the tripod. We all know how important it is, but we are expected to do this with great accuracy using a small bubble of air in a plastic blob of water. This seems kinda primitive to me.

The solution: a small oled screen device which can be permanently attached to the tripod (now I grant you we are getting into a turtles all the way down problem here.. what levels the level.. however lets ignore that for now), and shows you visually degrees out, plus dot digital bubble. it can use an extremely accurate accelerometer to do this.

total cost will be about 15 quid - esp32 dev board with battery and oled screen, accelerometer. and some noddy code to show it all graphically in an easy to see at night view.

I've looked around and can't see anything that does this. and trying to use a mobile phone is tricky because no flat surface on most mounts.

Now, of course a simple solution is a 'flat' deck fixed to the mount to put mobile phone on, and just use that.

But where's the fun in that ?

So - before I get hacking - has this been done before ?

In case useful to folk - I'm doing up the garden at the mo, and will be installing power sockets to end of garden where my 'observation deck' is.

I got one of these:

https://www.amazon.co.uk/gp/product/B08W5FS751/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

its a bit bright tbh, but I liked the look and it will be about 6 feet from the deck.

Anyway, I got some plastic 'lens repair tape' for broken car taillights, and opened it up, and packed as many layers as I had tape on top of it.

and it works really well as a red light. I'll have a handy switch up there and might add a remote so easy to flip on and off when I need it. Getting sick of red head torches and the like.

I did it! took it all to bit, flocked the lot, cleaned the mirrors, put it all back together and laser aligned it. I don't think the laser is exactly wonderful as if I rotate the thing in the 1.25 holder the laser goes from centre, to 1/2 outside edge.. but rolling it on a bit of glass and it seems steady... so who knows.

it's a heck of a lot better probably than it was though - at first the laser was hitting about 3" out from the centre of the primary! never mind the return path.

3 hours ago, david_taurus83 said:

I've made a couple of DSLR cooler boxes and created quite an extensive dark library for my 6D by 'matching' EXIF temps by controlling the ambient temperature around the camera. I can't see any real difference between using darks versus not using them. The 6D is very low noise already. It produces very clean stacks though I have only ever used mine from my light polluted back garden so when I remove the LP it does look noisy in areas of low signal. I would concur that not using darks and to dither is more beneficial. You must use a master bias though. The 6D bias is a whopping 2047 ADU out of a possible 16k ADU. It gives the impression that your lights are more washed out than they actually are so I try to expose until the histogram (in software, not on camera) is around the halfway mark.

thanks - good info there.

I assume you also use flats though ? if nothing else, to minimise dust/lens marks, etc?

huh. so you just shoot lights, and point DSS at your bias master as a dark ? and that works well for you I assume. Might give that a try then.

stu

So, searching the net this seems to be controvertial at the time. Has opinion solidified one way or the other ?

I'm referring to Clarkvisions in depth test and review of the original 6d (which I have) btw, not my own opinion - I'm just wondering if it's true not, as clearly it would save me a load of hassle and time...

https://clarkvision.com/reviews/evaluation-canon-6d/index.html

Specifically the summary paragraph:

" The constant dark level with long exposure time indicates the camera has on-sensor dark current suppression. This, however, does not suppress noise from dark current. But it results in a uniformly dark level that needs no post processing correction. No long exposure dark frames are needed when making long exposures if recording raw."

It does sort of tie in with what I was finding when I forgot and didn't have time to take darks - I even reprocessed an old shot or two without them to see if there was any difference, and then wondered what I was doing wrong when I couldn't see any.

Note: do read the article - he's not talking about not using darks if you turn on long exposure noise reduction and/or high ISO speed NR. He's saying with those off, there's no point in taking darks - since whatever thermal dark current noise is there at the temperature - is random so you ain't getting rid of it - and the camera does the rest.

Also, fascinating the difference in thermal noise with temperature. Really brings it out why folk use cooled CCDs! Look at those 1C pics !

no I mean, when you PA you are manually moving the mount. So then, afterwards it doesn't know where it's pointing. So you need to do the synscan align process again (reset first, then align with 2 or 3 star).

So minimum routine (assumes mount has moved since last session):

- level tripod, use summit like polar align pro app on mobile to get bearing and angle of WEDGE as spot on as you can.

- fit yer gear, and balance.

- turn stuff on, and start to use your camera ideally, and an RDF or whatever.

- reset alignment

-do align routine

- do PA routine

- reset alignment

- do align routine (which will now be much better since you've PAed, plus RA should be closer for tracking)

If you can be ar$ed - go around this once or twice more - you should get closer to just moving polaris left/right, up/down in the crosshairs of your camera with each PA attempt.

Once satisfied, goto and image as many targets as you like. You don't need to do this again unless you move the mount (but if you do plan to use it again without moving it after turning it off, be sure to use hibernate - but you'd have to PA again then anyway as different night, so not sure that adds much frankly)

Yeh, it seems to be fairly well accepted that the AZ GTIs are not exactly honed to perfection in the factory. I've seen folk saying their's was missing a thread for a balance bar for example. And some seen to have better tolerances and less backlash than others.

I've did the usual, and taken mine apart, re-greased it, adjusted the worm tensions, etc. Who know if it helped, but it feels as good as it's gonna get. But I do believe mine has terrible ALT accuracy for whatever reason. So taking that out the picture by running in EQ mode made a massive difference to me. Your results may vary.

But I've shot unguided 60 seconds with my 1300mm mak102 no problem (it came as part of a kit with the AZ GTI). Quite a lot of it comes down to how many times you go around the PA - since the nature of how the synapp process works means you really have to reset aligment and do your 2/3 star alignment again, then PA again, repeat.

Frankly I've only once had the patience to go around twice. But if shooting with long FLs I'd imagine that is key.

The other big EQ advantage (it is in the manual), is that you don't need to be connected to the app all the time on yer phone. just goto, and leave it tracking. I had bought a 2nd hand Samsung S7 and hardcase just so I can leave it out there with the mount and not have to have my mobile sitting close enough to the thing for hours while it imaged. Now, it's not required!

I don't have access to PHD2 - only what ASIAIR PRO exposes. But yes, life is short - I'd rather get the kit I really want than waste it away struggling. 🙂

3 hours ago, MKHACHFE said:

Beautiful pic. I was lucky enough to get 5 crystal clear, moonless nights near Portnaluchaig last autumn. Stunning beach location and B2...

 

It's a trip I will never forget. Also trekked for 7 hours up the fairly busy Ben Nevis summit trail. One of my best holiday. Seriously, that part of the UK is just jaw dropping. 

 

 

it's a video - one of my favourite flights. agreed - North West is one of the most amazing scenery on earth imho. I'm kinda glad it's not more popular - it's the isolation as much as the scenery that makes it for me. Then Ben and around there is another favourite of mine to fly - probably getting off topic now.

thanks Olly, so you're saying for my skymax 102 and 6d - I'm at the boundary already then. add a barlow and it's too much for the guiding ? that's a pity - not a lot of pixels to play with. 😕

54 minutes ago, tuckstar said:

I flocked my 250px. It does improve contrast. Mine was painted black inside but you can see the difference it makes below.

 

 

wow - that will be a yes then. 😀

1 hour ago, iapa said:

Here are some of steps I took collimating a reflector.

did you forget to post the steps ?

Surely it's the FL that decides if it's long or short ? I mean a 400mm FL with a 30mm Aperture would be an F13.3 (long) by this definition, but it's surely still 400mm - which isn't long surely ?

Or has long and short got a weird astro definition as well as every other camera term I've learned in the last 40 years ?

stu

Hi chaps - er new to this collimating lark. I bought a svbony laser collimator and it shows it's well off - reflected laser not even hitting target !

But my old Helios just seems to have fixed philips screws in base and base sides ? The spider has adjusatable knobs though. I'm assuming the primary locking screws are under the bottom and it's a base plate cover thing ?

Am I likely to be able to do a decent job with this laser ? I'm not looking for perfection, and I figured it'd be easier than a cheshire thing. But I don't want to spent hours faffing about and failing only to then ask on here and be told I was wasting my time.

https://www.amazon.co.uk/Telescope-Collimator-Bysameyee-Calibrator-Collimation/dp/B07J5WBG4K/ref=dp_prsubs_1?pd_rd_i=B07J5WBG4K&psc=1

Second thing is, as I'm going to flock about with it (yes.. it is the cheap pun you suspected), is it worth me just taking the spider off and flocking the inside ? It is painted black, so is there really much gain in flocking it ?

Lastly.. it's pretty old, and been sitting in someones loft for years - the main mirror is pretty dusty and one big (im hoping) hair rather than scratch visible - if I take it apart and carefully wash it (following you tube videos - distilled water, etc) am I likely to get it back together again, or am I best leaving that alone ?

cheers

stu

p.s. ignore mental 3 in one mount - that's coming off and putting a top dovetail on and will mount stuff to that.

yup - pro app takes you through it. I find it soo easy now. It knocks asiairs method into a cocked hat imho. takes a few mins only.

I had an adventurer on order, but with the performance and easy/vesatility of the gti in eq mode, I swapped the FLO order for another GTI - then yesterday decided one was enough and I'd use the cash towards an EQ6-R.. but point remains.

I just got an M12 threaded rod (7 quid), some bolts, propeller nuts. printed a standard dumbell weight to M12 spacer on my 4d printer, and used 2 spare 1.25 dumbell cast iron weights. And I use it with an ioptron wedge as they were the cheapest. weight easily screws off for transport or AZ mode.

It's a no brainer really honestly - you'll never look back. I really need to try it out with my EQStarPro and guiding - I'm keen to see what accuracy it gets - with easily getting 120 sec unguided, could I hit 5 mins+ ?

I've been mainly using it with my SLR lenses - and that 120 secs is with an APS-C 1200D, and a 1.4x extender with my 300mm L F4. i.e. 1.6x1.4x300 (672*). I've shot 90 secs with  the 2x extender (840*).

*FL pedants - leave me alone - my mind works in 35mm and it's not changing now 😛

you dont need a polarscope Lee, synsapp does the work. I get 2 mins reliably with 72ed unguided

On 17/04/2021 at 20:40, AstroNebulee said:

Thank you Stu that's very kind of you. It just goes to show as you say you can do deep sky on alt az mounts quite easily, I know I'm pushing my mount to the limits but so worth it, since processing these I've learnt a new way to process so will give them another go and repost. Here ia a re process of M51 The whirlpool galaxy from earlier in the week 

that really is excellent. And that is unguided ?

I didn't even try to attempt it with my az gti in eq mode - just didn't think it could do it - went for it last week with my 6d, SW 72ED and EQ5 mount, guided, but didn't get anthing like as good as you got. I was shooting 90 second lights, and forgot to shoot any calibration frames.  result below 😞 I shot it 2 nights later with my mak 102, which maybe approaches your result, but that was at 300 seconds. I think I DEFINATELY need to try my AZ GTI on it (though will be in EQ mode ! (boo hiss i hear - can't post to this thread).

so hope following images allowed even though with EQ - it's as a comparison to show why skill and talent and an AZ mount beats a monkey in charge of an EQ mount.

SW 72ED (heavily cropped):

MAK 102 (heavily cropped):

haha, fair enough. I've been using my tripod unextended, and I reckon that should fit just about. But yeh, extended - not way.

"what pier ? you mean the high tech designer bird perch I've put in the garden ?"

yeh it's got pegs, and it will be sitting on concrete base circle anyway (I'll peg it out with bungies to the grass. I ordered a green one, so could blend in reasonably.

Of course like all these pop-ups, there's the 'blackbelt kata' you need to learn to 'pop' it back down. 🤪

And if it's not that shower proof, a spray coat of waterproofing should do it. Obviously I'd being the scope, cameras  in, - but a bit of humidity isn't going to do a mount or asiair, etc any harm once in a while. I'm beginning to get a nervous twitch when I hear 'polar alignment'.. so anything that can make that need doing less (or adjusting less at least) has got to be a good thing.

The other thing I plan to do is carefully drill little indents into my circular patio where the tripod legs go (2" stainless steel EQ6 tripod). that will make it easier to position it exaclty the same place each time. just need to get em in the right place!

stu