20 replies to this topic

[MakNewtMan]

I'm at a bit of a crossroads here trying to decide if I should upgrade my camera or upgrade my telescope.  The goal is to make an improvement in the quality of my imaging results.  I'm aware that seeing conditions, collimation, sky conditions, etc.. all affect the overall end result of an image but all things being equal should I upgrade my camera or telescope?  Here's my current gear setup.  

 

I currently image with a QHY165C camera (APS-C OSC camera 16 megapixel and 4.83 micron size pixels) 

 

and 

 

a 6" maksutov newtonian comet hunter (731mm focal length at F 4.8)

 

 

 

I like the focal length of the scope so am looking for something similar in focal length.  My question here is upgrading something like an Orion Optics UK CT8 newtonian with their excellent optics make for a noticeable improvement in my imaging?

 

or

 

Should I keep the mak newt and upgrade to a better camera like the QHY268C or ZWO ASI2600MC pro?  

 

Ideally I'd like to upgrade both but the budget will only allow for one..

 

 

Which one do you think would yield me the best results in an upgrade?  Also, I am open to suggestions on other scopes or cameras in the $2200 price range that would be as good or better options.  

 

Thank you!

[avarakin]

What are the issues with your current images? Maybe post a sample.

[ryanha]

Have you considered a monochrome camera and narrowband imaging?

 

That can really unlock another dimension in imaging.

 

--Ryan

[MakNewtMan]

Not so much an issue with the current images so much as wondering if the upgrade from one optical system(my current mak newt) to a "higher end" 1/10th wave RMS optical system (the OOUK Newtonian) would make a noticeable difference in my images using the same camera? Am I better off getting a higher res, higher QE astronomy camera like the 2600MC pro or would there be a better improvement in my images with the scope upgrade. I like my scope but it is an entry level scope and so the optics are likely not the greatest.  really just trying to get some sound advice from someone that may know better than me.  I'm really not sure what would be the better move. 

[whwang]

Could you show an example image from that scope?  Mak-Newt has coma, but I am not sure if it is noticeable in your current setup or a potential full-frame setup.  If the coma is noticeable, then of course upgrading to a standard Newtonian with a good coma corrector is a way to upgrade and will not cost that much.

[MakNewtMan]

The mak newt doesnt suffer from coma since that what the Maksutov corrector plate fixes, but the mirror may be pinched or something because no matter how well i collimate it the stars always look a little bit more triangle shaped than round.  Not horribly triangular but it's noticeable. 

 

Here is a picture of M45 I did with the 6" David levy Coment hunter Mak Newt scope and my QHY165C camera. 

 

https://ibb.co/cLQjH8p

[JamesTX]

If you are having an issue with pinched optics or something like that with the scope.. changing out the camera isn't going to help.  For ease of use, in that price range you can get a nice refractor.  Leave enough room for a autofocuser and you'd be set.  Then while you are shooting with the refractor.. see if you can get explorer scientific look at the comet hunter and fix whatever is wrong with it.

[avarakin]

I don't like the stars on your image - they are bloated and have busy diffraction artifacts.

I suggest to upgrade the scope. 

You can get a nice refractor, but keep in mind that cheaper ones tend to produce bloated stars too.

In case if you are not intimidated by collimating RC, get one. Keep in mind, they may be addictive - I started with 6", then bought 8" and finally 10".

Once collimated properly, it can deliver great image quality. 

You will need a decent mount for RC, given that they have longer FL than your current scope.

 

Alex

[MakNewtMan]

That probably wasn't the best example image.  There was some bad processing on my part too.  Here is another image with the same scope and camera. 

 

https://ibb.co/YLL68zm

 

This one does have a halo in the middle but that could be removed in processing.  What do you think of the rest of the stars? 

[avarakin]

Looks much better, although stars seem to have some elongation. Is it because of tracking issues? If so, maybe you should upgrade mount. 

What mount do you have?

[wizer]

Looks much better, although stars seem to have some elongation. Is it because of tracking issues? If so, maybe you should upgrade mount. 

What mount do you have?

Based on AstroBin and profile pic, EQ6-R Pro.

 

I think you need to provide details such as guiding setup also.

 

Personally, if I were in your shoes I would look at getting another option for focal length to allow me to target other objects. That is unless my current scope was simply not producing usable data. Although if you are planning to sell your mak-newt to get the new scope, then perhaps the same FL would make sense IMO.

[MakNewtMan]

That image had limited data and half the images had streaks due to cable snags / poor guiding in bad seeing conditions. And yes it is the EQ6-R pro. I’ve got plans to add a longer focal length scope for galaxies but my main priority right now is either going with a quality Newtonian / refractor of similar focal length or a higher resolution / more sensitive camera. That’s my main concern at the moment.

[whwang]

Mak-Newton should have coma.  My understanding is that the Mak corrector only corrects for spherical aberration.  You did not notice coma probably because it's not severe under your FoV.  If you switch to a larger camera, you will see coma, combined with some weak field curvature.  Given the stars you show, I would say upgrading the scope first.

[Jared]

I assume that your expectation is to upgrade one now and the other later? Followed by a better mount eventually? Then a roll-off-roof observatory? And heavier mount and scope one day?  Just joking, of course, but in order to know where to spend your budget it's important to know whether this is foundational or final state. If foundational, I'd actually put money into the mount first. If end state, I'd probably do the telescope first, though I'd lean towards a 5" refractor and flattener over the 8" Newtonian just because it is much easier to get it working at its full potential, while the Newt will need fairly constant maintenance and will probably generate more frustrating experiences than the refractor. Things like pinched optics, collimation, tube flexure depending on altitude of your target, etc. are generally more work to overcome (and don't stay 'fixed') than things like back spacing on a flattener.

 

The real answer, though, is to get whichever piece of equipment will bring you the most fun. It's impossible to say with any degree of confidence which one will give you the biggest benefit in data quality.

[MakNewtMan]

I assume that your expectation is to upgrade one now and the other later? Followed by a better mount eventually? Then a roll-off-roof observatory? And heavier mount and scope one day?  Just joking, of course, but in order to know where to spend your budget it's important to know whether this is foundational or final state. If foundational, I'd actually put money into the mount first. If end state, I'd probably do the telescope first, though I'd lean towards a 5" refractor and flattener over the 8" Newtonian just because it is much easier to get it working at its full potential, while the Newt will need fairly constant maintenance and will probably generate more frustrating experiences than the refractor. Things like pinched optics, collimation, tube flexure depending on altitude of your target, etc. are generally more work to overcome (and don't stay 'fixed') than things like back spacing on a flattener.

 

The real answer, though, is to get whichever piece of equipment will bring you the most fun. It's impossible to say with any degree of confidence which one will give you the biggest benefit in data quality.

Thanks for the advice. I really am trying to up my game overall and make this more of a foundational move.  I honestly hadn't thought of the mount as a possible first upgrade over the scope but now that you mention it, it's something I'll consider.  I have my eye on a couple 5" refractors that would fit the bill and like you said likely be less of a head ache to have it working at it's full potential.  Seems like at this point overall the recommendation would be to go for a solid refractor.  

[fetoma]

Looks like focus could be improved. That would help a ton.

[avarakin]

You can get a mono camera, that will allow to collect data faster and also open up narrowband imaging. 

[Rasfahan]

I would chime in and say go for focus. Your stars have small halos, and it might be the focus. If you don‘t have it yet, a motorized focuser will allow you to better mail focus and use an autofocus routine. The other possibility is that it is diffraction artifacts from the camera - ones with a backlit sensor will not have that. The spiky diffraction is probably from pinched optics, probably the mirror. I do not know enough about the Mak-Newt to tell you how to correct that, but you surely can find something about that. That said, with a refractor there is less hassle - if the halos are from microlenses, it will not help, though.

[pejorde]

Not so much an issue with the current images so much as wondering if the upgrade from one optical system(my current mak newt) to a "higher end" 1/10th wave RMS optical system (the OOUK Newtonian) would make a noticeable difference in my images using the same camera?

A Newtonian will add big, ugly diffraction spikes, loads of coma and probably will require frequent collimation. You will need a good, expensive coma corrector which in turn requires accurate back spacing. In short, you buy a new set of problems.
Or you can try working out the problems with your current imaging procedure and equipment. Your images are very nice but quite soft. I wonder how much is due to processing and how much to the data? Do you have a good dew-prevention system?

 

Per Erik

[MakNewtMan]

A Newtonian will add big, ugly diffraction spikes, loads of coma and probably will require frequent collimation. You will need a good, expensive coma corrector which in turn requires accurate back spacing. In short, you buy a new set of problems.
Or you can try working out the problems with your current imaging procedure and equipment. Your images are very nice but quite soft. I wonder how much is due to processing and how much to the data? Do you have a good dew-prevention system?

 

Per Erik

I kind of like the diffraction spikes and I'm accustomed to collimating my mak newt pretty much every other time before I image so not too worried about that. However, I've always wondered about the softness of some of my images.  I use a bhatinov mask to attain focus and check it every hour or so depending on how the temperature drops.  I've suspected that my scope does have pinched optics as I have tried correcting it before by loosening the mirror clips a bit and it still seems to be an issue.  Will likely have to reach out to Explore Scientific on that.  I do use dew heaters so no issue there.  Course on the otherhand a 5" refractor does sound tempting as it would be much less hassle. Thanks for chiming in. 

[Eric Seavey]

Honestly, I think the images are pretty decent.  I am wondering if you have your gain set too high.  What image capturing tool are you using?  What processing software are you using?  Are you using a light pollution filter? Are your stars not natural colors because you are using a light pollution filter?   I found the Astronomik CLS-CCD produces pretty natural looking star colors, which I strictly use for emission nebulae.  All other targets I strictly use a IRUV filter.  Also my Astronomik filters reduced the halos significantly! I have a similar setup as you with a Mak-Newt and a QHY APS-C camera.  Careful and correct collimation of a Mak-Newt unleashes its full potential.  I also use Sharpcap for my capture, and use focus-assist with a Bahtinov Mask.  Sharpcap also has tools to measure your camera, and give you the best settings for the  sky conditions where you want to image.