Can't get focused photos with DSLR though telescope.

[MauriceN]

So I got myself a used 1000D with astromod for my 130/1000 newtonian and tried to take some test images the last night. I put on the tring, screwed on the adapter and secured it in the focuser. Sadly I didn't get to see anything but a little slightly orange dot after that (test object was saturn). I tried using my eyepieces (25mm, 15mm and 10mm) as well through eyepiece projection but the closest I got to an image was a very blurry picture of the aperture. I can't seem to focus "enough" to get clear images with the eyepieces, and without, planets are just a shining blob.

[Lolly Eater]

I read somewhere the distance from sensor to the eyepiece lens, needs to be 55mm but I'm in the same boat as you! Hoping all this wizardry will become science, and I will know what I am doing before I get disillusioned! Lets hope someone who knows what they are doing, will take pity on us Maurice.

[Davey-T]

Don't know about your scope but some Newtonian scopes don't have enough inwards travel on the focuser to reach focus with a DSLR, have you tried using a Barlow lens in front of the camera ?

Dave

[MauriceN]

37 minutes ago, Davey-T said:

Don't know about your scope but some Newtonian scopes don't have enough inwards travel on the focuser to reach focus with a DSLR, have you tried using a Barlow lens in front of the camera ?

Dave

Just tried it with a barlow lens but it doesn't seem to work either. (15mm plössl + 2x barlow)

 

I tried to get some information from other sources and it seems like the problem is the 55mm restriction on newtonians. There are 2 solutions: new focuser or moving the mirror further to the front... both not worth for the pricerange my telescope is in. So the only solution now is getting rid of my newtonian and buying a refractor?

[Alien 13]

Most of the 130mm reflecting scopes (unless specially designed like the 130mm PDS) and a high percentage of 150mm ones will not have enough inward focus travel. The fix suggested by Dave should work, a 2X barlow on its own in the image train.

Alan

[MauriceN]

1 minute ago, Alien 13 said:

Most of the 130mm reflecting scopes (unless specially designed like the 130mm PDS) and a high percentage of 150mm ones will not have enough inward focus travel. The fix suggested by Dave should work, a 2X barlow on its own in the image train.

Alan

My last try didn't work, but if you say so I'll give it another try with the barlow..

[MauriceN]

I seem to have missed the planet on my first try. If I use a 2x barlow with eye piece projection it seems work (if orange blurry blob with 15mm + 2x barlow as mars counts as working - I'll try saturn and jupiter tomorrow). Sadly the adapter chain is extremely long and heavy now and doesn't seem very stable. Is there any one-piece alternative?

[astrosathya]

2 hours ago, MauriceN said:

I seem to have missed the planet on my first try. If I use a 2x barlow with eye piece projection it seems work (if orange blurry blob with 15mm + 2x barlow as mars counts as working - I'll try saturn and jupiter tomorrow). Sadly the adapter chain is extremely long and heavy now and doesn't seem very stable. Is there any one-piece alternative?

You are using a 15mm eyepiece and 2x barlow. Thats not the way to do it. Don't use the 15mm eyepiece along with the Barlow. Use only the Barlow followed by the camera. The purpose of the Barlow is to bring the focus outward. 

[MauriceN]

On 19/07/2018 at 06:53, astrosathya said:

You are using a 15mm eyepiece and 2x barlow. Thats not the way to do it. Don't use the 15mm eyepiece along with the Barlow. Use only the Barlow followed by the camera. The purpose of the Barlow is to bring the focus outward. 

I don't see anything without an eyepiece in between, though. I'll try it again today..

[rickwayne]

I highly recommend that you attempt to find focus with your camera in daylight first. At the very least you should be able to see which way to turn the focus knob. Measuring the drawtube extension isn't a bad idea either, then you can quickly return to that neighborhood in the dark.

[MauriceN]

I tried it only with the barlow lense, but it doesn't work. The only thing I can see halfway clear is the moon, everything else is blurry/the aperture. Adding the eyepiece doesn't work either. I'm clueless.. Would a 3x barlow be the next step?

[Merlin66]

Hmmm, probably not the x3 barlow....

Using an eyepiece (eyepiece projection) will push the magnification up and cause other issues.....practise with the basics -with/ without a barlow before moving on.

If you can focus on the moon, then you should be able , at the same settings, to focus on all other astronomical objects.

The blurryness you see could be due to the atmosphere.......

 

[Buzzard75]

Using a DSLR and a barlow with a 1000mm focal length scope is going to produce a small, blurry, detailess image of the planets. You're seeing the atmosphere as well as any sort of vibration in the scope. The moon is so large, it's a completely different story and a much easier target. All the images you see of planets are from having taken video, stabilizing the frames, aligning the frames and then stacking the frames. They are not single frames. It's also best if you use the 5x view feature of something like BackyardEOS to achieve a 1:1 pixel scale when taking planetary video.

Below are two images. Both are taken using a 1500mm telescope, a 2x barlow and a DSLR camera. One is just a single frame from the video using a full view. The other image is about 1000 frames using the 5x view in BackyardEOS that have been stabilized, aligned and stacked. If you're getting something like the single frame, don't sweat it. If you're expecting something like the other, your expectations may be too high.

 

[astrosathya]

15 hours ago, MauriceN said:

I don't see anything without an eyepiece in between, though. I'll try it again today..

It is quite surprising. I have a Ritchey Chretien Astrograph (cassegrain) which also has trouble focusing on Moon and planets, but I simply use extension tubes plus barlow to achieve focus. Works for me. regardless of the type of scope, back focus issue can be typically resolved using a barlow. As someone said, try doing this during the daytime. point the scope at a distant church steeple/mobile phone/electricity tower (ideally more than a kilometer away) and try to focus. If nothing works, take the scope to your nearest astronomy club. I am sure that if someone takes a good look at your setup, they might be able to see something we haven't been able to see via messages.

[adyj1]

You do need to be able to achieve focus on a distant object in the daytime to prove that your imaging train can be brought to focus. Another suggestion for night viewing is to try to focus on one of the bright stars - Vega is in a convenient position at the moment. As you turn your focuser you should be able to see the star focus from a blurred ring to a tight pinprick and the start blurring again. If you can't focus "through" the pinprick state and back out again with a barlow you are going to have problems. Whether you are happy with how small a pinprick you achieve will depend on the accuracy of your focuser...