Stub Mandrel

Not a spectacular image - this little camera has a webcam sized chip, the same as in the  ASI120MC, but the mono version.

This is the best of 125 16-second frames stacked in DSS without flats darks or bias. The little companion galaxy is visible but my skies hide the outer envelope.

39 minutes ago, Marvin Jenkins said:

One thirty second exposure after another until something whizzes by. Nothing happens, delete and start again. Perhaps the key is spare batteries and huge memory cards.

My dual battery hand grip is good for about 3-4 hours. A 16GB card is good for 3 or four sessions with the 450D.

12 minutes ago, John said:

Hmmm, I'm not convinced that the £120 investment in an ADC would deliver significatly improved views of Jupiter and Saturn in this case. I've had some very nice views of both planets lately from the UK and while their low altitude has created some challenges with seeing stability from time to time, I've not noticed the tell tale signs of atmospheric dispersion specifically affecting the views.

I suspect that the original poster might get better results by checking the collimation of the scope, ensuring that it's cooled and by observing these targets for a good period of time to allow the observing eye a chance to adjust to the contrasts and to gradually pick out more details.

At least those steps are cost free and can be put into practice on the next clear evening

 

I don't think an ADC is essential for observing as I think the eye accomodates to the dispersion after a bit.

That said, I set up my ADC for photography by using an eyepiece in place of the camera. The setting isn't super critical compared to focusing but I find the improvement easy to observe, and it's also possible to see when you have 'gone too far'.

(At the moment dispersion is very marked through a camera, but adjusting is difficult as the planet moves across the sensor when you change the setting so you end up having to make a small changes, re-centre the planet and repeat - an optical setting is just much quicker).

Here's my spreadsheet that I used to analyse last year's data from SpectrumLab. I just counted the hourly totals manually.

My view is that false detections will be of two kinds: Totally random, that just lift the baseline, and missed or double detections which will be random but proportional to the amount of meteors. Neither of these has a significant impact on the proportionality of the readings, so take the absolute numbers with a pinch of salt, although inspecting screen captures suggests there are few false detections.

As no detection setup will get more than a percentage of meteors and it's impossible to be sure exactly what your area of search is, I think the only scientifically valid result for  is comparing readings at different times with the same location and setup (and possibly weather). That said it's interesting to compare detections of really big meteors and to note things like ISS and plane passes.

Perseids 2018.xlsx

Don;'t make the exposures too long - faint meteors disappear into the skyglow.

25 minutes ago, A_N_other_beginner said:

Even though it'd mean a stack including a cheap and basic barlow?
I can see the value of an ADC, but in a combination including a good and a basic (and presumably optically inferior?) barlow I'm wondering how much the benefit of the ADC would be offset by that cheaper piece of glass in the middle. Am I barking up the wrong tree regarding the barlow?
If I already had the barlow I'm considering (Televue 2x) I'd not be thinking about the weak link quite so much, but I genuinely don't know what sort of difference there is between a £20 barlow and a £100 one.

Consider the Rvelation Astro ED Barlows for plenty of quality for rather less than £100.

On 08/08/2019 at 07:21, Saganite said:

Just to add to what has been said so far, I was able to see the main bands with  small amounts of detail and the Great Red Spot at just 74x in my 4" refractor, two nights ago.

On the night of the recent eclipse I could see two bands on Jupiter in my 2" Tasco scope 🙂

My C90 Mak easily revealed the Red Spot and Io's shadow recently as well at 40x.

7 minutes ago, iwols said:

your a star

Maybe a planet 🙂

Just now, iwols said:

is an adc the right way to go?

It's a big help at the moment. My mars images were useless until I got one.

Just now, iwols said:

do you capture as avi, and the file was a single png image now ive looked

Do you have more PNGs? If so you can throw them all in PIPP.

If you use 'quick capture' you can set it to grab 5,000 frames.

4 minutes ago, iwols said:

using sharpcap,but do i select raw 8 and avi?

May as well, more than 8 bits won't bring you any benefits.

What do you have at the moment?  You should be able to get something from your data if that's a single frame.

Download PIPP and install it, if you haven't already and then ltry an follow my instructions

2 minutes ago, iwols said:

ide be more than happy with that,not got my head round debayering yet

What is your workflow?

I suggest:

Put into PIPP using the settings for 'planetary' just accept the defaults for now, but make sure:  'debayer raw image frames' and  'debayer monochrome frames' are checked on the 'input options' tab and  'stretch histogram white point' and 'equalise R,G and B channels individually' are checked on the 'processing options' tab.

Put the resulting AVI into Autostakkert!3.

Run analyse, then tell it to put alignment points on, then stack a percentage of frames. AS!3 shoudl do an RGB align to minimise the dispersion.

Processing shoudl be a combination of sharpening and contrast enhancement, maybe with some colour balancing.

(PIPP and Autostakkert are both free).

Perhaps all is not as bad as you think.

I did an RGB align in registax on the colour balanced version. It still isn't brilliant but some colour detail on the disc is appearing.

So sharpen in Astra Image and there's even a hint of stuff in the rings. Is the original one frame from a video or a stacked image?

29 minutes ago, iwols said:

like this

I don't think that's the fault of the C8.

For a start, it isn't debayered - it's actually a colour image:

The blue at the top and red at the bottom shows the need for an atmospheric dispersion corrector at the moment - you will lose all fine detail otherwise.

The colour balance is way off as well, unsurprising as it hadn't been debayered:

I  think the focus is poor - try focusing on a relatively nearby star, Altair at a push.

I think this is a single frame? The hot pixel suggests it is, if so it's possibly a bit over-exposed as well.

Finally, I would aim for 5,000 frames with as short an exposure as you can get away with - use maximum gain and rely on stacking 500-2000 frames to get rid of the noise.

Don't give up of the C8, but if you want to swap it for my 150PL... this is what I've got this year, the C8 ought to be able to beat this.

What sort of results are you getting? Unless you have both a good night and an ADC you won't get particularly good results with any scope at the moment from the UK.

The C8 is, ironically, more susceptible to bad seeing than smaller scopes.

LOL! I did something similar with my 'Aldi Special;' severa;l years ago! Less contrast - major problem with it at high magnification.

10 minutes ago, MarsG76 said:

Still shouldn't be that much difference when the conditions play ball...

Yes... but I'm still kicking myself for going into a shop that was getting out of astro and buying a cheap C90 Mak instead of grabbing the new C9.25 on an tracking Alt-Az mount for about £700  😭

1 hour ago, mark skelton said:

Ok cheers, what's then best way of selecting said frame?

Do a 'register checked pictures' but without 'stack X% of pictures' ticked.

Right click on the frame with the highest score and  choose 'set as reference frame'.

4 hours ago, cabfl said:

I recommend waiting for the new CMOS sensors that QHY and ZWO have presented:

and remortgaging...

7 hours ago, MarsG76 said:

8"... I use a C8...

Damn!

47 minutes ago, wesdon1 said:

wow so you got images that good with 150mm aperture!

Thanks!

See the pics @MarsG76 has got with a 6" scope in Australia - that's what I'm hoping for in the future!

48 minutes ago, wesdon1 said:

i didn't go out celebrating, i spent the whole night alone with my new toy!

You probably saved half the cost of the scope - and missed the hangover! 🙂

Why image the moon in Ha?

Because my scope was set up and focused but it wasn't dark enough to start guiding reliably. However, it seems that this approach allowed me to cut through the seeing and atmospheric dispersion so I got a really sharp image.

Canon 450D, astro modded and cooled. I Used PIPP to isolate the red channel as a mono image from about 100 subs and stacked the best.

Canon 450D, astro-modified and cooled. 130P-DS with coma corrector. Baader 7nm Ha filter. HEQ5, guided. 21 5-minute subs. Stacked in DSS and processed in Photoshop and Astra Image.

Canon 450D, astro-modified and cooled. 130P-DS with coma corrector. HEQ5, guided. 18 5-minute subs. Stacked in DSS and processed in Photoshop and Astra Image. Uncropped.

Well done!