Newbie DSLR questions

[ninjageezer]

Hi all new to the forum and the hobby,i have a sky-watcher 250p flex and a canon 60D ,i would like to take images of mainly planets and i realise im limited due to the dobsonian mount .

before i buy any of the wrong kit i thought i would ask the experts on here.i dont mind spending money on the correct bits if needed to get the best results. i understand there is sometimes a focus issue ,i would like to attach the camera with maybe a barlow or powermate to get higher magnification.i have read and watched so much on this subject i am confused.....i really would appreciate a step by step of what to buy and how to connect ,,,,the software image processing side of it i am quite confident in its just the hardware.

[ninjageezer]

ok so nobody uses a dobsonian with a DSLR on here 😒

any pointers please,

[wulfrun]

First question you'll likely get asked: is the scope the "Go-To" version or not? If it can't track the object it'll limit you to short exposures (i.e. only the brightest objects). You'll likely need a Barlow to achieve focus unless you can change out the focuser to a low-profile one. Not sure if that's feasible or not on your scope. I think a focal extender/powermate won't shift focus out far enough, again not sure.

Just to be clear, I'm not an imager, I have only tried casual use of a camera on dob-type mounts and these are my understanding of the problems you'll face. Then there's field-rotation of the images but I believe there are ways around that, I never looked further into it. I think using a Dob is one of those "yes, it's possible but it's hard work" things, although you seem to be well aware of that.

Over to the experts now...just thought I'd throw in a reply so you don't feel no-one's looking!

[ONIKKINEN]

For planets and the Moon you would want to use a barlow anyway so the focus issue is no problem. If yours is the non go-to version then you will have to deal with drifting obviously.

Planetary and Lunar is best done by shooting a video with very high framerates, which is something that DSLRs are not best suited for. I dont know if the 60D has an uninterpolated crop mode to shoot video with, but if it does you could use that. My 550D has a "movie crop mode" which takes a 480p area on the center of the sensor and records that to a video. This is usable because there is no pixel skipping involved. In other video modes like 1080p or even 4k or whatever you typically have pixel skipping where entire rows of pixels are just skipped for the recording. This makes the actual capture resolution very bad and pretty much unsuitable for planetary, and not that great for lunar.

But for the Moon you can just shoot individual frames without the video recording hassle and either use those as your image or try to stack the individual frames. For stacking you should take as many as your patience can endure. Shoot away until the Moon has drifted to the edge and re-center. Obviously with the tracking dob would be much easier but no real reason you cant do this without the tracking base. You can also shoot planets this way, but your framerate will be terrible and so its not that great, but will get you started and some results.

Although my image here was taken with a tracking mount, you could do the same with fast exposure times untracked, just takes fiddling around. This is the sort of image you could expect from a single shot Jupiter (i took this with the 550D and a VX8, cropped quite a bit):

Its not the best image, but you can recognize it as Jupiter and a shadow of one of the moons on it.

If you want to spend money on a proper planetary camera then there are many options to choose from, but all require the use of a computer or capture device of some sort to use them.

[ninjageezer]

18 hours ago, wulfrun said:

First question you'll likely get asked: is the scope the "Go-To" version or not? If it can't track the object it'll limit you to short exposures (i.e. only the brightest objects). You'll likely need a Barlow to achieve focus unless you can change out the focuser to a low-profile one. Not sure if that's feasible or not on your scope. I think a focal extender/powermate won't shift focus out far enough, again not sure.

Just to be clear, I'm not an imager, I have only tried casual use of a camera on dob-type mounts and these are my understanding of the problems you'll face. Then there's field-rotation of the images but I believe there are ways around that, I never looked further into it. I think using a Dob is one of those "yes, it's possible but it's hard work" things, although you seem to be well aware of that.

Over to the experts now...just thought I'd throw in a reply so you don't feel no-one's looking!

Hi thanks for the advice ,no its not a goto just a std dob mount.

[wongataa]

22 hours ago, wulfrun said:

You'll likely need a Barlow to achieve focus unless you can change out the focuser to a low-profile one.

You can get short T adaptors for Canon cameras which means you should be able to achieve focus with a stock focuser.

[wongataa]

On 03/02/2022 at 22:51, ninjageezer said:

Hi all new to the forum and the hobby,i have a sky-watcher 250p flex and a canon 60D ,i would like to take images of mainly planets and i realise im limited due to the dobsonian mount .

before i buy any of the wrong kit i thought i would ask the experts on here.i dont mind spending money on the correct bits if needed to get the best results. i understand there is sometimes a focus issue ,i would like to attach the camera with maybe a barlow or powermate to get higher magnification.i have read and watched so much on this subject i am confused.....i really would appreciate a step by step of what to buy and how to connect ,,,,the software image processing side of it i am quite confident in its just the hardware.

You can do it with your setup.  You will need a short t adaptor to attach your camera to the telescope.  You should be able to unscrew the eyepiece holder from the adaptor that attaches it to the focuser and screw on the t adaptor.

https://www.firstlightoptics.com/adapters/baader-ultra-short-canon-eos-t-ring.html

https://www.firstlightoptics.com/adapters/ts-ultra-short-t2-adapter-for-canon-eos-1mm-length.html

You will need to set your camera to record video.  Higher frame rates are better which means DSLRs can be at a disadvantage here but there is no harm in trying to see what you get.  You frame the planet in the view of the camera and start recording video.  When the planet moves out of the frame you move the telescope to get the planet back in frame.  When you have decided that you have taken enough video of the planet travelling across the field of view stop recording.

You will need the following pieces of software which are free: PIPP, AutoStakkert, and RegiStax.

This video - https://youtu.be/oHhbF0LvnxU - shows you how to use them to get a single clear image of the planet.

I have got pictures of Jupiter & Saturn with my Skywatcher 150p Dobsonian and Canon camera this way.

[alacant]

1 hour ago, wongataa said:

short T adaptors

Hi

We find it easier -and more economical- to simply clamp the tube a cm or so shorter. Any eos T2 ring will do.

Cheers

Edited February 6, 2022 by alacant

[ninjageezer]

2 hours ago, wongataa said:

You can do it with your setup.  You will need a short t adaptor to attach your camera to the telescope.  You should be able to unscrew the eyepiece holder from the adaptor that attaches it to the focuser and screw on the t adaptor.

https://www.firstlightoptics.com/adapters/baader-ultra-short-canon-eos-t-ring.html

https://www.firstlightoptics.com/adapters/ts-ultra-short-t2-adapter-for-canon-eos-1mm-length.html

You will need to set your camera to record video.  Higher frame rates are better which means DSLRs can be at a disadvantage here but there is no harm in trying to see what you get.  You frame the planet in the view of the camera and start recording video.  When the planet moves out of the frame you move the telescope to get the planet back in frame.  When you have decided that you have taken enough video of the planet travelling across the field of view stop recording.

You will need the following pieces of software which are free: PIPP, AutoStakkert, and RegiStax.

This video - https://youtu.be/oHhbF0LvnxU - shows you how to use them to get a single clear image of the planet.

I have got pictures of Jupiter & Saturn with my Skywatcher 150p Dobsonian and Canon camera this way.

brilliant just what I was after ,what about Barlow/powermate for magnification ?  oh and for some reason my scope focuser does not unscrew I'm thinking its not the original one ,I have seen videos of this and mine is a 1 piece moulded version that goes into the 2 inch focus chamber, so im guessing the adapters shown are of no use to me.....

[ninjageezer]

2 hours ago, alacant said:

Hi

We find it easier -and more economical- to simply clamp the tube a cm or so shorter. Any eos T2 ring will do.

Cheers

hi can you explain a bit more what you mean ,clamp what tube shorter ?

[alacant]

1 hour ago, ninjageezer said:

clamp what tube shorter

 

On 03/02/2022 at 23:51, ninjageezer said:

sky-watcher 250p flex

'... flex' 

So I believe you have the collapsible tube.

So...

Using a T2 adapter and nosepiece, see if your camera reaches focus. If it does, do nothing. 

If not, to enable focus to be reached, extend the telescope as normal. Now loosen the clamps holding the extension rods and push it back from whence it came a centimetre at a time until until camera comes to focus. Mark and clamp at that position when you want to do photography.

Cheers and HTH

 

[ninjageezer]

4 minutes ago, alacant said:

 

'... flex' 

So I believe you have the collapsible tube.

So...

Using a T2 adapter and nosepiece, see if your camera reaches focus. If it does, do nothing. 

If not, to enable focus to be reached, extend the telescope as normal. Now loosen the clamps holding the extension rods and push it back from whence it came a centimetre at a time until until camera comes to focus. Mark and clamp at that position when you want to do photography.

Cheers and HTH

 

Awesome thank you so much

[ninjageezer]

23 minutes ago, alacant said:

 

'... flex' 

So I believe you have the collapsible tube.

So...

Using a T2 adapter and nosepiece, see if your camera reaches focus. If it does, do nothing. 

If not, to enable focus to be reached, extend the telescope as normal. Now loosen the clamps holding the extension rods and push it back from whence it came a centimetre at a time until until camera comes to focus. Mark and clamp at that position when you want to do photography.

Cheers and HTH

 

what would you suggest to get more magnification i was looking at the tele vue powermates/barlows 

[alacant]

36 minutes ago, ninjageezer said:

more magnification

Our moon guy uses this, but sorry, I've no hands on with it. I'm certain there'll be more economical -and lighter- items suggested herein.

HTH

 

[happy-kat]

practice without increasing magnification as increasing magnification will make manual tracking harder

[ninjageezer]

yes good advice i will practice first thank you .but i will soon need more mag for the planets im guessing..i have my eye on a used tele vue  powermate 5x is this too much ?

ive seen some good photos taken with it .

Edited February 6, 2022 by ninjageezer

[happy-kat]

under Resources, Astronomy Tools (top of page) you can enter your telescope and DSLR and select image and the Moon to see what size it would be.

[wongataa]

9 hours ago, ninjageezer said:

what would you suggest to get more magnification i was looking at the tele vue powermates/barlows 

If you want more magnification a Barlow will work.  Get a decent one to minimise chromatic aberrations.  You will need a nosepiece to attach to the t adaptor which then fits into the Barlow like an eyepiece.  You may need a 2" Barlow to not have any vignetting with your camera - I'm not sure.  They are more expensive.

Edited February 7, 2022 by wongataa

[wongataa]

9 hours ago, alacant said:

 

'... flex' 

So I believe you have the collapsible tube.

So...

Using a T2 adapter and nosepiece, see if your camera reaches focus. If it does, do nothing. 

If not, to enable focus to be reached, extend the telescope as normal. Now loosen the clamps holding the extension rods and push it back from whence it came a centimetre at a time until until camera comes to focus. Mark and clamp at that position when you want to do photography.

Cheers and HTH

 

I forgot you can do that with a collapsible dob.  I have a solid one so it isn't possible for me.