14 replies to this topic

[jmcooper]

I am very new to Astrophotography and do not yet have a computerized setup. I'm using a Canon EOS T8i with a Celestron 8se telescope. I  have the T-adapter and have my camera mounted directly to the back of the 8se. When I point the telescope at the full moon, I am too zoomed in to fit the entire moon in the frame. I'm wondering if there is a solution to this or if the two devices just don't work well together for imaging the full moon. This is the T-adapter I'm using and I'm wondering if there is a shorter T-adapter that would give me less zoom (not sure if that even makes sense, I'm a total novice with optics, too). Is there anything else I can do to get more zoomed out?

 

I was hoping to image the lunar eclipse tomorrow night, but I suspect I'm going to need some sort of different equipment and I'm probably too late to get what I need.

Edited by jmcooper, 14 May 2022 - 09:43 PM.

[ataanzali]

Hello,
The problem is not the T-adapter and its length. You need to either use a focal reducer or use a full-frame camera to fit the entire moon in. This is just the function of the magnification you get with your 8" celestron with its native focal length. In order to see a wider Field of View you either need to reduce your focal length or increase your sensor diameter.

Hope this helps!

Ata

[17.5Dob]

That's the huge problem using an SCT. There's simply way too much focal length for imaging anything but planets, globular clusters and small galaxies...... You need a 0.7x focal reducer to fit the moon in a single frame of your camera.

[jmcooper]

A focal reducer makes sense; thank you both.

[Normmalin]

ataanzali beat me to it.  I just had the same problem 2 nights ago -- the video coverage of my asi533 is only a portion of the full frame coverage so it takes about 10-12 frames to cover the moon and that was with a 0.7x reducer (so 1400mm focal length).  You should go to a wider field scope or lens.

[bobzeq25]

There is no magic solution for doing this with a long focal length SCT.  A camera lens is an option.  Getting one setup properly by tomorrow night is an issue.

Edited by bobzeq25, 14 May 2022 - 10:31 PM.

[vidrazor]

The Celestron .63 reducer would give you the field of view you see below, but you would have to have one by tomorrow, which is probably out of your reach.

 

However as long as you're tracking, you can shoot two images of the moon in quick succession, as you can also see below, and stitch them up in the freebie Microsoft ICE, which is an easy to use program. Just make sure you have sufficient overlap, which as you can see below should not be an issue. This will allow you to grab the moon with your existing setup, and have a pretty high res image to boot. Just make sure you shoot relatively quickly to remain in the same phase.

 

Hope this helps, good luck!

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Edited by vidrazor, 14 May 2022 - 10:40 PM.

[steveward53]

The Celestron .63 reducer would give you the field of view you see below, but you would have to have one by tomorrow, which is probably out of your reach.

 

However as long as you're tracking, you can shoot two images of the moon in quick succession, as you can also see below, and stitch them up in the freebie Microsoft ICE, which is an easy to use program. Just make sure you have sufficient overlap, which as you can see below should not be an issue. This will allow you to grab the moon with your existing setup, and have a pretty high res image to boot. Just make sure you shoot relatively quickly to remain in the same phase.

 

Hope this helps, good luck!

For 'normal' imaging this would be my solution , it's a method I use with my DSLR and Mak180Pro at times.

 

But good luck trying to capture a lunar eclipse in this manner .... !

[vidrazor]

For 'normal' imaging this would be my solution , it's a method I use with my DSLR and Mak180Pro at times.

But good luck trying to capture a lunar eclipse in this manner .... !

Well that's why I said to shoot two successive images quickly to remain in the same phase. It can work, and if he doesn't have any options, he certainly has nothing to lose by trying.

[Jay6879]

The Celestron .63 reducer would give you the field of view you see below, but you would have to have one by tomorrow, which is probably out of your reach.

 

However as long as you're tracking, you can shoot two images of the moon in quick succession, as you can also see below, and stitch them up in the freebie Microsoft ICE, which is an easy to use program. Just make sure you have sufficient overlap, which as you can see below should not be an issue. This will allow you to grab the moon with your existing setup, and have a pretty high res image to boot. Just make sure you shoot relatively quickly to remain in the same phase.

 

Hope this helps, good luck!

 

+1 for ICE, fantastic program. It's a bit more work to get the final image but you end up with a much higher resolution moon than if you just got in one shot with less focal length. This isn't a full moon shot (I messed up one of the panels ugh) but it's still a five or six panel mosaic done with an Orion Apex 102 and an asi224mc (which is very zoomed in!)...

 

 

[Normmalin]

Question - so you folks are taking single frames for the moon?  I was under the impression one needed to collect video due to turbulence and then use codes such as registax to stack the frames.  When I did that, I was limited to HD resolutions (1920x1080) so it took maybe 10 frames to cover the entire moon at 1440mm.  Is there no advantage to the video approach for the moon?  

 

Thanks!

[vidrazor]

Question - so you folks are taking single frames for the moon?  I was under the impression one needed to collect video due to turbulence and then use codes such as registax to stack the frames.  When I did that, I was limited to HD resolutions (1920x1080) so it took maybe 10 frames to cover the entire moon at 1440mm.  Is there no advantage to the video approach for the moon?  

Thanks!

You can go either way actually. Especially so if you're tracking the moon, you can shoot full res at a high shutter speed, and fire off a series of frames quickly and stack them in an image editor using a median process. You don't need a lot, maybe 10-20 frames or so. In this particular scenario with the eclipse, you would need to shoot and reposition quickly, and such a setup will probably work. Although I have not pieced two (or more) images like this together, I've shot the moon exactly like this, on a regular tripod no less (for the 8se, you would need to be tracking), and fired off a rapid series of frames using and infrared camera trigger.

 

Nikon 1 V3 w 300mm f/4.5 Ai Nikkor @ f/5.6, ISO 160, 1/125 sec, 16 frames stacked median in Photoshop, multi layer unsharp mask and smart sharpen.

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Edited by vidrazor, 15 May 2022 - 02:20 PM.

[Jay6879]

Question - so you folks are taking single frames for the moon?  I was under the impression one needed to collect video due to turbulence and then use codes such as registax to stack the frames.  When I did that, I was limited to HD resolutions (1920x1080) so it took maybe 10 frames to cover the entire moon at 1440mm.  Is there no advantage to the video approach for the moon?  

 

Thanks!

 

That image above your post was done with video. I took a 3 minute video, then moved it over (making sure there was decent ovelap), then another three minute video etc. 

 

You'll get much nicer image doing it the video route as opposed to a single image.

[Normmalin]

That image above your post was done with video. I took a 3 minute video, then moved it over (making sure there was decent ovelap), then another three minute video etc. 

 

You'll get much nicer image doing it the video route as opposed to a single image.

 

That's what I wondering - thanks!  In my case, I get 3008x3008 samples with my edgehd/asi533 combo so I could take a single frame (or sets of single frames) and get half the moon, then move and repeat.  Whereas with the video, I only get a portion of that and the mosaicking becomes more important.

 

Thanks for everyone's answers!

 

Norm

[steveward53]

Question - so you folks are taking single frames for the moon?  I was under the impression one needed to collect video due to turbulence and then use codes such as registax to stack the frames.  When I did that, I was limited to HD resolutions (1920x1080) so it took maybe 10 frames to cover the entire moon at 1440mm.  Is there no advantage to the video approach for the moon?  

 

Thanks!

When I tried using an 1100D in video mode the reults were terrible , the video output is a series of jpegs captured from the Liveview stream and you had to save everything to an SD card and couldn't save the stream straight into the laptop. Not sure about your 850D but I suspect it's the same.

 

I just shoot single frames with my 1000D for Solar or 450D for Lunar , the shot I took in preperation for the eclipse the other day was a stack of 120 frames from a quick 240 shot ,  the more you stack the better the result as far as a nice smooth result in all those 'blank' grey areas , provided you nail the focus ( I have the advantage of a cheap laptop controlled remote focus controller ) the results are fine .

 

Turbulence-wise you just have to make the best of the conditions you are landed with , it's such a large object with so many features that it's not unusual to see great clarity in one crater and a complete mess a little way away , just let the software make the best of it , it's a lttle easier for my solar stuff as I cherry pick by eye the best frames as there are much fewer areas of interest generally .

 

My prep shot turned out fine , the eclipse didn't happen thanks to the weather.