Would a 114mm SynScan Reflector be good for astrophotography?

[flord.lord]

Regarding doing AP with "unsuitable" mounts, here are two interesting theeads....

https://stargazerslounge.com/topic/2281 ... challenge/
https://stargazerslounge.com/topic/2790 ... challenge/

Wow those are amazing photos for an EQ3...I'm blown away!

If this is what you can get with an EQ3, why does everyone use HEQ5s etc., spending hundreds more? (just a question)

Surely I'll be able to salvage something half as good as this with an EQ2, RA motor and DSLR (Fuji X-T)
I'm thinking of getting
https://www.firstlightoptics.com/sky-wa ... scope.html

I know it's a tiny amount of money compared to a dedicated AP rig, but... ?

Just to be clear I'm trying to set my expectations low, so I'm not expecting this (from the EQ3 thread)


But rather something like

[ARock]

There are 2 potential problems with the setup you propose.

1. Newtonian reflectors and DSLRs don't work very well. Mainly because a newtonian design usually does not have enough backfocus for a DSLR to come into focus with it. There are special reflectors which allow this (the description should say if the reflector will work with a DSLR).

2. The reflector in your setup, is too heavy for the mount for the accurate tracking that is needed for AP. Heck it might be too heavy even for visual. The payload for good AP should be about half the payload the mount allows for visual.

The only way you get good performance out of that mount, is if you put a very light weight refractor, or just your DSLR with a zoom lens on it. But this will create wide field shots of the night sky.

The EQ 3 challenge features a mount better than the one in your link. Visual payload = 5Kg. AP payload = 2-3kg (approx)
https://www.firstlightoptics.com/skywat ... eluxe.html
However, the 50% load for AP rule is not cast in stone, and you will notice some people use it with a 150p reflector. But they might use a lighter camera.

You can mount a light weight refractor on the 3-2 like
https://www.firstlightoptics.com/startr ... 0-ota.html

Refractors work better with DSLRs. Add an accurate RA motor to the EQ3-2, and you will get 20-30-60s shots with it. Add guiding and you can do 2-3-5 min exposures. It is still a lot more difficult than a dedicated AP mount, mainly in 2 areas. Polar alignment, and finding a target (no Goto). But it can be done as the EQ3 challenge shows.

An AP mount is also much more precise in its engineering (which is why it costs more), and there are a lot of battles to fought doing AP with a mount meant for visual. But it can be a good learning experience at a lower cost with results that you may find acceptable.

[Greenman]

Mark, I’m sure you are a philosopher, as you are Plato like. But that could be a platonic thought.

[flord.lord]

There are 2 potential problems with the setup you propose.

1. Newtonian reflectors and DSLRs don't work very well. Mainly because a newtonian design usually does not have enough backfocus for a DSLR to come into focus with it. There are special reflectors which allow this (the description should say if the reflector will work with a DSLR).

2. The reflector in your setup, is too heavy for the mount for the accurate tracking that is needed for AP. Heck it might be too heavy even for visual. The payload for good AP should be about half the payload the mount allows for visual.

The only way you get good performance out of that mount, is if you put a very light weight refractor, or just your DSLR with a zoom lens on it. But this will create wide field shots of the night sky.

The EQ 3 challenge features a mount better than the one in your link. Visual payload = 5Kg. AP payload = 2-3kg (approx)
https://www.firstlightoptics.com/skywat ... eluxe.html
However, the 50% load for AP rule is not cast in stone, and you will notice some people use it with a 150p reflector. But they might use a lighter camera.

You can mount a light weight refractor on the 3-2 like
https://www.firstlightoptics.com/startr ... 0-ota.html

Refractors work better with DSLRs. Add an accurate RA motor to the EQ3-2, and you will get 20-30-60s shots with it. Add guiding and you can do 2-3-5 min exposures. It is still a lot more difficult than a dedicated AP mount, mainly in 2 areas. Polar alignment, and finding a target (no Goto). But it can be done as the EQ3 challenge shows.

An AP mount is also much more precise in its engineering (which is why it costs more), and there are a lot of battles to fought doing AP with a mount meant for visual. But it can be a good learning experience at a lower cost with results that you may find acceptable.

Thanks a lot for the info. In fact, today after I posted that I discovered that a DSLR in the scope does not reach focus unless a Barlow is used.

I guess apart from that, my last strand of hope is afocal AP. I know it is done with phones but I'm not quite sure what it entails. Wouldn't the DSLR lens be too big for the small eyepiece hole?

Then there's eyepiece projection, with no camera lens screwed on to the EP (?)

What quality images could I expect?

Thanks.

[ARock]

I don't know much about afocal, but some people have taken decent pics with their phones and a large reflector.

If you do want to try prime focus AP with an EQ2 mount, you can get a 60-80mm short tube refractor for it. Some of these are really cheap used. Or you could just use it with a 50-200mm lens on the DSLR for wider field shots. But such a setup with a short tube refractor is not very good for visual for DSOs.

If you want to go for visual with some afocal phone shots (planets/moon), a 6-8 inch Dobsonian is the best value.

[Harmonious]

Just about everyone who posted says is saying, 114+EQ1 or 2+DSLR = Disappointment. That the 114 is not a good choice for AP and that a base level GEM will not make you happy.

By now I expect that you have checked into afocal imaging and EP projection.. You will have followed up on the virtues of short focal length refractors etc. You have discovered by test one of the limits of using a Newtonian.

Let's cut right to the big chase. Use whatever you want and learn from the experience. Don't ask about a method when you can look up instructions and try it. Try it in the daytime or at night with a streetlight or lighted window. The target won't move, it will be just you, the optics and the camera. When you are ready for an astro target, you will be less overwhelmed.

Go take pictures, good bad or indifferent. The experience will do you more good than posting. And good luck, the first part of the curve is daunting but it gets to be fun.

[JayTee]

Use whatever you want and learn from the experience. Don't ask about a method when you can look up instructions and try it. Try it in the daytime or at night with a streetlight or lighted window. The target won't move, it will be just you, the optics and the camera. When you are ready for an astro target, you will be less overwhelmed.

Go take pictures, good bad or indifferent. The experience will do you more good than posting. And good luck, the first part of the curve is daunting but it gets to be fun.

Thank you, thank you, thank you!!!

This statement should be reiterated over and over again to beginners. There is no better teacher than experience! I would add one thing to one of your sentences, "Go take pictures, good, bad, or indifferent [they cost you nothing but your time].

Thanks again,
JT

[OhNo]

Tom is Wise! Unlucky but wise. How do I know this, I tried imaging with a poor mount. The frustration vs satisfaction was tilted significantly to the frustration side!!!

[flord.lord]

I don't know much about afocal, but some people have taken decent pics with their phones and a large reflector.

If you do want to try prime focus AP with an EQ2 mount, you can get a 60-80 mm short tube refractor for it. Some of these are really cheap used. Or you could just use it with a 50-200 mm lens on the DSLR for wider field shots. But such a setup with a short tube refractor is not very good for visual for DSOs.

If you want to go for visual with some afocal phone shots (planets/moon), a 6-8 inch Dobsonian is the best value.

Thanks, this is what I needed!
[mention]ARock[/mention]
I'll go for the 130/650 reflector and focus on visual but at least attempt afocal and see what happens.

If I decide to pursue DSO imaging, I will purchase a ST80 - the images I am seeing with one are stunning (to a beginner )

Again, thanks this for this - If it wasn't for this thread I would've probably ended up making a stupid purchase and been utterly disappointed!

[flord.lord]

Just about everyone who posted says is saying, 114+EQ1 or 2+DSLR = Disappointment. That the 114 is not a good choice for AP and that a base level GEM will not make you happy.

By now I expect that you have checked into afocal imaging and EP projection.. You will have followed up on the virtues of short focal length refractors etc. You have discovered by test one of the limits of using a Newtonian.

Let's cut right to the big chase. Use whatever you want and learn from the experience. Don't ask about a method when you can look up instructions and try it. Try it in the daytime or at night with a streetlight or lighted window. The target won't move, it will be just you, the optics and the camera. When you are ready for an astro target, you will be less overwhelmed.

Go take pictures, good bad or indifferent. The experience will do you more good than posting. And good luck, the first part of the curve is daunting but it gets to be fun.

Great. I will get the 130/650 and focus mainly on visual (I couldn't edit the title) - If I want more than what I see from afocal (likely), I will get an ST80 on the EQ2 (very lightweight I understand it), and do imaging.

Thanks for your help

[ARock]

Thanks, this is what I needed!
@ARock
I'll go for the 130/650 reflector and focus on visual but at least attempt afocal and see what happens.

If I decide to pursue DSO imaging, I will purchase a ST80 - the images I am seeing with one are stunning (to a beginner )

Again, thanks this for this - If it wasn't for this thread I would've probably ended up making a stupid purchase and been utterly disappointed!

The jump from your current 4" to 130mm means a light gathering increase of 1.6-1.7x. This might not change your views significantly.

Another option would be to spend the same amount on a better mount, the EQ3-2 and try to mount your 114mm reflector on it. Then you have a much better mount when you go for AP.

[flord.lord]

Thanks, this is what I needed!
@ARock
I'll go for the 130/650 reflector and focus on visual but at least attempt afocal and see what happens.

If I decide to pursue DSO imaging, I will purchase a ST80 - the images I am seeing with one are stunning (to a beginner )

Again, thanks this for this - If it wasn't for this thread I would've probably ended up making a stupid purchase and been utterly disappointed!

The jump from your current 4" to 130mm means a light gathering increase of 1.6-1.7x. This might not change your views significantly.

Another option would be to spend the same amount on a better mount, the EQ3-2 and try to mount your 114mm reflector on it. Then you have a much better mount when you go for AP.

[mention]ARock[/mention] A good idea, but I have a 100mm, not a 114mm (I was originally going to buy a 114mm at the beginning of this thread but have changed my mind).

Manufacturers say that 114 to 130 is a 30% light gathering jump, so 100 - 130 must be averagely significant?

[Lady Fraktor]

Manufacturers say that 114 to 130 is a 30% light gathering jump, so 100 - 130 must be averagely significant?

It is actually a bit of a meaningless statement, difference in aperture by size but tells you nothing really.
At a 15mm increase in aperture you will start to notice a difference in image scale, at 20mm a definite difference.
Your 100mm should work fine for getting started doing some afocal photography.
It will definitely work well for visual.

[ARock]

@ARock A good idea, but I have a 100mm, not a 114mm (I was originally going to buy a 114mm at the beginning of this thread but have changed my mind).

Manufacturers say that 114 to 130 is a 30% light gathering jump, so 100 - 130 must be averagely significant?

The 30% comes from the ratio of the area of aperture ie. the approx equation (130/114) squared = 1.3
Compared to the 100mm (130/100) squared = 1.69.
It will show you more but might not be enough, but that depends on you.

It is tricky to try to cater to both visual and AP at the same time.

For example: If you want visual alone the skywatcher heritage 150p tabletop is considered a great scope in that price range similar to the AWB Onesky in the US. It will have 2.25x more light gathering from your 100mm. Here is a thread about it.
https://www.cloudynights.com/topic/4631 ... t-borders/

If you want beginner AP in that price range with the addition of a 80mm refractor the EQ3-2 is a better mount, but no new OTA which means you have to use your current OTA.

If you want both visual and AP potential the 130p is decent, but realize that you are giving up a bit on both visual and AP that is possible in that price range. And it might well be the best tradeoff for you, I am just pointing out the different options that you have,

[ARock]

For example: If you want visual alone the skywatcher heritage 150p tabletop is considered a great scope in that price range similar to the AWB Onesky in the US. It will have 2.25x more light gathering from your 100mm. Here is a thread about it.

Correction: The AWB Onesky although a flextube is the same specs as your 130P.
The Skywatcher Heritage 150P is larger.
https://www.firstlightoptics.com/beginn ... scope.html

[flord.lord]

@ARock A good idea, but I have a 100mm, not a 114mm (I was originally going to buy a 114mm at the beginning of this thread but have changed my mind).

Manufacturers say that 114 to 130 is a 30% light gathering jump, so 100 - 130 must be averagely significant?

The 30% comes from the ratio of the area of aperture ie. the approx equation (130/114) squared = 1.3
Compared to the 100mm (130/100) squared = 1.69.
It will show you more but might not be enough, but that depends on you.

It is tricky to try to cater to both visual and AP at the same time.

For example: If you want visual alone the skywatcher heritage 150p tabletop is considered a great scope in that price range similar to the AWB Onesky in the US. It will have 2.25x more light gathering from your 100mm. Here is a thread about it.
https://www.cloudynights.com/topic/4631 ... t-borders/

If you want beginner AP in that price range with the addition of a 80mm refractor the EQ3-2 is a better mount, but no new OTA which means you have to use your current OTA.

If you want both visual and AP potential the 130p is decent, but realize that you are giving up a bit on both visual and AP that is possible in that price range. And it might well be the best tradeoff for you, I am just pointing out the different options that you have,

I have seriously looked at the 150p, but backtracked and thought, “no, this is £30 more expensive than the 130p and I'm trying to get off a TableTop mount”. Seriously, those TableTops are back-breakers at the Zenith!

[ARock]

True, table tops have their own set of problems, especially the need for a table and the zenith hole. Reflectors on EQ mounts have theirs with tube rotation, and instability when undermounted.
Good luck with whatever you end up getting.