Ande

On 13/01/2021 at 02:43, AstroRuz said:

DHL lost the tripod? Bit of a big thing to misplace! 

They misplaced my house 😳 Been in all day today waiting for them to perform a collection. They elected not to bother. Nice of them to not bother letting me know either 🤨. 

Excellent purchase! I have an Artcise tripod.  Really sturdy and light.

Turned up earlier today.....  A Williams Optics guide scope https://www.firstlightoptics.com/finders/william-optics-32mm-slide-base-uniguide-scope.html and a Williams Optics diagonal https://www.firstlightoptics.com/diagonals/william-optics-125-dura-bright-dielectric-diagonal.html. Also a WO t-connector thing for the Canon, but not worth picturing.

All appear to be lovely quality items. I bought the guidescope to replace a ZWO guide scope that was really disappointing. The difference between the two is quite significant. I think I’m turning into a WO a fanboy. Loving their stuff

On 15/01/2021 at 13:22, Sidecontrol said:

Let us know how it is, once you've tried it!

It turned up a couple of hours ago. I haven’t had a chance to test it yet, but it does seem a nice step up in quality. It feels like it actually represents the price paid, whereas the ZWO felt like fifteen quid’s worth.

You not got one kicking about in a drawer somewhere? I seem to have dozens of the things 😀

20 minutes ago, johninderby said:

RACI and Telrad or Rigel is the way to go. Telrad / Rigel to get you roughly in the area then RACI to zero in.

Notice just how many go this route after trying other things. It simply works.

 

That was the route I took with the Skywatcher 250dob. Works beautifully. I bought the Skywatcher RACI and it offered stunning views in it’s own right 😀

Excellent 🙂🙂

15 minutes ago, Roy Foreman said:

There is a trade off with ISO settings. Low settings like 200 will give higher quality and can be pushed further during post processing to bring out details, but will require longer exposure times. Higher settings like 6400 will reduce your exposure times quite dramatically but will produce a lot more digital noise. Generally you can offset this but taking several identical shots and stacking them together (I usually take 5 or 7) in photoshop.

 

As a guide for the Pleiades, try 5 x 60 sec at ISO 6400 and see what you get.

Let us know how it turns out

Next time out I shall try a quick experiment at higher ISO. However, if I can increase my exposure lengths significantly, then I would rather work with ISO 200.

10 minutes ago, vlaiv said:

Depends.

Both are right, but differences might not be what you expect.

ISO is just multiplication factor - meaning that it does not change SNR - which is signal to noise ratio (multiply top and bottom of fraction with same number and fraction does not change). In that sense - after you enter region where there is no quantization effects - there is no difference between ISO 200 and ISO 800, except in full well capacity and one more thing.

What is this other thing? It is read noise. With CMOS sensors - some of the noise is injected before A/D conversion and some of it after A/D conversion.

This means that part of read noise is subject to "amplification" by ISO. This means that total read noise is actually smaller at higher ISO values. This is best seen if you look at read noise vs Gain settings for astro cameras (not sure if anyone made such graph for DSLRs):

So higher ISO offers somewhat lower read noise because of that.

Now, read noise is combated with exposure length (depending on your light pollution) - so it is not that important - unless you are forced to use short exposures.

Conclusion?

If you use short exposures - then take care of read noise and use high ISO, but if not - consider ISO to be of no importance and "fixed" for your purposes.

Wow! Thank you. That is quite a lot of information there. I shall need time to digest, and understand it. I am aiming for longer exposures. My first night out I really wanted to grab some quick exposures before the clouds rolled in, mainly so I could check out the mechanics of DSS. But my exposures were way too short, to the point that DSS rejected them. That’s when I got into the ISO mini debate. I shall be aiming for up to 3 minutes at a push. We’ll see how that transpires😂

9 minutes ago, fifeskies said:

ISO 200 is the best setting but will mean longer exposures which is fine if you have a tracking mount or are guiding.

 

My Canon has best setting at ISO 800  (600D) and at that I use 120 sec subs on the Pleiades (with my 4 inch ED scope).

at ISO 200 this equates to 480 sec (in my scope) , which I could do as I often image at 360 sec subs.

If you cant expose that long without trails then by all means crank up the ISO but I would limit it to 800 or 1600.

 

Remember you wont see a lot in the single frame and will need to stack then stretch to get a final image.

below is a single 120 sec frame (at ISO 800) compared to a stacked and stretched version (20 subs)

 

That is very helpful, thank you. I am using a Skyguider Pro, so should be okay with longer exposures. I’ve just bought a guide camera too, but not had a chance to become acquainted with it as yet. Next time out I am going to make it my mission to find out what max exposure time I can reach.  That is a stunning final image by the way

Hi all. Just trying to get my head around what the ISO setting for my Canon 80D should be. Now, I understand how ISO works during regular, terrestrial photography, and how the need for varying the ISO is a factor.  However, after reading this article: http://dslr-astrophotography.com/iso-values-canon-cameras/ it is suggested that, when it comes to astrophotography, there is no advantage to be had by increasing the value beyond the optimum setting, which,  for my particular camera, is an ISO value of 200, as the SNR rises considerably alongside the ISO.
 

When I last attempted imaging, I stuck with this setting of 200 and tried, unsuccessfully, to capture the Pleiades. As it turned out, my exposure time was way too short due to my inexperience. But, in the back and forth that followed, it was suggested by a few members that my ISO needed cranking right up, which in complete contrast to what the article above is telling me.  So, is there a general consensus? Do I stick with, what appears to be, hard fact, or do I take the article with a pinch of salt?

I had problems the other day. It wouldn’t let me look at any manuals, but I managed to download a driver, and some software. Think the website is a bit buggy.

Will do 🙂

Well, the poor quality has got the better of me and I’ve ordered a replacement scope. Went with this one from Williams optics: https://www.firstlightoptics.com/finders/william-optics-32mm-slide-base-uniguide-scope.html

A fair bit lighter than the ZWO Mini, and also like the measurement marking guide printed along the side. Handy for if it ever gets packed away.  Just hope it’s better quality. 

14 minutes ago, Waddensky said:

Space Engine is great. It supports different kinds of VR headsets and the new nebula rendering engine is breathtaking. You can also build and control spaceships, which is really great to understand orbital mechanics. I'm not really sure, but it's possible that an older stand-alone version is still available as a free download. 

Celestia is free, but no longer maintained as I recall correctly. 

Thank you. I’ve just been reading the reviews on Steam.  10/10 and people comparing it to a god-like experience. Unfortunately, I’m working away from home for a while. The second I get back I shall be all over this 🙂

I’ll have a peep. There was also one called Sandbox Universe, or something like that.  I did a bit of Googling, and, as ever, it seems they all have their strengths and weaknesses. I shall dig deeper 😀

If you ordered from FLO it may be worth checking their stocks. They look a lot healthier today than they did yesterday. I’ve been looking at telescopes, and certainly the Williams Optics stuff is suddenly plentiful apart from the Space Cat, which had probably been subject to back orders. Might be worth seeing if the bountiful harvest has spread across all brands.

Just wondered if any of you were using any packages that were able to show the beauty, and scale of the universe? I don’t mean Stellarium or Sky Safari etc. I do have both of those, and they are invaluable for showing what’s where etc. But they are, to me, merely practical, as opposed to being particularly entertaining.

I’ve just become aware of Space Engine, which looks incredible. And it’s very reasonably priced too, and available on Steam. But, before I splash out, are there any similar options for me to consider? My absolute dream would be to have something like this in VR, but accept that it is pretty unlikely.

20 minutes ago, Phillyo said:

You can't bin a DSLR due to it being a one shot colour camera. That being it'll have a bayer matrix over the sensor that is something like RGGB. Binning is used with mono cameras (someone correct me if I'm wrong).

Thanks for clarifying. That is one less idea for me to try to get my head around, which is no bad thing. Consider the notion binned

Like many others on here, my little brain is trying to piece together the purpose, and practicalities of all of these weird and wonderful concepts. Is there any merit in using binning with a DSLR?  Also, being a beginner, is it just something I should sidestep for the time being, until I’m more experienced? I’ve recently bought an ASIair Pro, which has yet to see first light, and binning seems to be one of the many functions on offer.

I hadn’t even thought of looking at Canon’s own software. Something else for me to look into. I hope the clouds don’t part for the next 3 months, as I shall be way too busy 😂

Much appreciated 🙂

Yes, that is definitely an option on the camera, and not a bad idea. I think I may already have Adobe Bridge on the laptop, as part of the CS2 package, although I could be wrong. I’ll check on that next time I fire it up. 
 

Much appreciated 🙂

That looks like it’s really been looked after.  Good find

1 hour ago, david_taurus83 said:

I had the Astro essentials mini guide scope which is very similar in design. The front barrel was also loose on that before you tightened. A good upgrade is to get the non rotating helical focuser which makes focusing a breeze after you get rough focus with the front barrel. I'd hazard a guess the SVBony helical focusers available on ebay for half the price of the ZWO are identical..

 

That looks like a nice upgrade.  And I agree that the SVBONY one is probably identical. The only thing that stops me grabbing one is that it is all extra weight. And, given that I’m perching everything on a Skyguider, I have to be a bit weight conscious. 

25 minutes ago, nephilim said:

I've read some negative comments about this guide scope, I went for the Skywatcher 50ED which seems really good quality.

 

Very wise. I think the ZWO’s main redeeming feature is that it is small, and lightweight. But the love affair ends there for me.